Definition and Epidemiology

Definition

DermatomyositisDermatomyositisA subacute or chronic inflammatory disease of muscle and skin, marked by proximal muscle weakness and a characteristic skin rash. The illness occurs with approximately equal frequency in children and adults. The skin lesions usually take the form of a purplish rash (or less often an exfoliative dermatitis) involving the nose, cheeks, forehead, upper trunk, and arms. The disease is associated with a complement mediated intramuscular microangiopathy, leading to loss of capillaries, muscle ischemia, muscle-fiber necrosis, and perifascicular atrophy. The childhood form of this disease tends to evolve into a systemic vasculitis. Dermatomyositis may occur in association with malignant neoplasms.Paraneoplastic Syndromes (DMDMDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus) is an idiopathic, immune-mediated, inflammatory myopathy that causes progressive, symmetric,proximal muscle weaknessProximal Muscle WeaknessLambert-Eaton Myasthenic Syndrome and characteristic cutaneous manifestations.

Antisynthetase syndrome is a subtype ofDMDMDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus characterized by the presence of antisynthetaseantibodiesAntibodiesImmunoglobulins (Igs), also known as antibodies, are glycoprotein molecules produced by plasma cells that act in immune responses by recognizing and binding particular antigens. The various Ig classes are IgG (the most abundant), IgM, IgE, IgD, and IgA, which differ in their biologic features, structure, target specificity, and distribution.Immunoglobulins: Types and Functions and accompanied by certain extramuscular manifestations.

Epidemiology

• Fewer than 5,000 people in the U.S. havedermatomyositisDermatomyositisA subacute or chronic inflammatory disease of muscle and skin, marked by proximal muscle weakness and a characteristic skin rash. The illness occurs with approximately equal frequency in children and adults. The skin lesions usually take the form of a purplish rash (or less often an exfoliative dermatitis) involving the nose, cheeks, forehead, upper trunk, and arms. The disease is associated with a complement mediated intramuscular microangiopathy, leading to loss of capillaries, muscle ischemia, muscle-fiber necrosis, and perifascicular atrophy. The childhood form of this disease tends to evolve into a systemic vasculitis. Dermatomyositis may occur in association with malignant neoplasms.Paraneoplastic Syndromes.
• The annualincidenceIncidenceThe number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from prevalence, which refers to all cases in the population at a given time.Measures of Disease Frequency rate is 1 per 100,000 people.
• Women are twice as likely to be affected.
• Bimodal age of presentation:
  • 5–15 years of age
  • 45–60 years of age
• Peak onset is at about 50 years of age.

Etiology and Pathophysiology

Etiology

• Exact etiology unknown
• Possible genetic factors:
  • HLA-DR3
  • HLA-DR5
  • HLA-DR7
• Environmental triggers:
  • Infectious:
    • Coxsackie BvirusVirusViruses are infectious, obligate intracellular parasites composed of a nucleic acid core surrounded by a protein capsid. Viruses can be either naked (non-enveloped) or enveloped. The classification of viruses is complex and based on many factors, including type and structure of the nucleoid and capsid, the presence of an envelope, the replication cycle, and the host range.Virology
    • EnterovirusEnterovirusA genus of the family picornaviridae whose members preferentially inhabit the intestinal tract of a variety of hosts. The genus contains many species. Newly described members of human enteroviruses are assigned continuous numbers with the species designated ‘human enterovirus’.Coxsackievirus
    • Parvovirus
    • Human T cell lymphotropicvirusVirusViruses are infectious, obligate intracellular parasites composed of a nucleic acid core surrounded by a protein capsid. Viruses can be either naked (non-enveloped) or enveloped. The classification of viruses is complex and based on many factors, including type and structure of the nucleoid and capsid, the presence of an envelope, the replication cycle, and the host range.Virology type-1 (HTLV-1)
    • ToxoplasmaToxoplasmaToxoplasmosis is an infectious disease caused by Toxoplasma gondii, an obligate intracellular protozoan parasite. Felines are the definitive host, but transmission to humans can occur through contact with cat feces or the consumption of contaminated foods. The clinical presentation and complications depend on the host’s immune status.Toxoplasma/Toxoplasmosis
    • BorreliaBorreliaBorrelia are gram-negative microaerophilic spirochetes. Owing to their small size, they are not easily seen on Gram stain but can be visualized using dark-field microscopy, Giemsa, or Wright stain. Spirochetes are motile and move in a characteristic spinning fashion due to axial filaments in the periplasmic space.Borrelia
  • Medications:
    • NSAIDsNSAIDSPrimary vs Secondary Headaches (diclofenacDiclofenacA non-steroidal anti-inflammatory agent (nsaid) with antipyretic and analgesic actions. It is primarily available as the sodium salt.Nonsteroidal Antiinflammatory Drugs (NSAIDs))
    • Antibacterials (penicillinPenicillinRheumatic Fever,sulfonamidesSulfonamidesA group of compounds that contain the structure so2nh2.Sulfonamides and Trimethoprim)
    • Antineoplastic agents (hydroxyureaHydroxyureaAn antineoplastic agent that inhibits DNA synthesis through the inhibition of ribonucleoside diphosphate reductase.Antimetabolite Chemotherapy,cyclophosphamideCyclophosphamidePrecursor of an alkylating nitrogen mustard antineoplastic and immunosuppressive agent that must be activated in the liver to form the active aldophosphamide. It has been used in the treatment of lymphoma and leukemia. Its side effect, alopecia, has been used for defleecing sheep. Cyclophosphamide may also cause sterility, birth defects, mutations, and cancer.Immunosuppressants)
    • InterferonsInterferonsInterferon (IFN) is a cytokine with antiviral properties (it interferes with viral infections) and various roles in immunoregulation. The different types are type I IFN (IFN-ɑ and IFN-β), type II IFN (IFN-ɣ), and type III IFN (IFN-ƛ).Interferons
    • Anti-tumornecrosisNecrosisThe death of cells in an organ or tissue due to disease, injury or failure of the blood supply.Ischemic Cell Damage factor drugs
    • StatinsStatinsStatins are competitive inhibitors of HMG-CoA reductase in the liver. HMG-CoA reductase is the rate-limiting step in cholesterol synthesis. Inhibition results in lowered intrahepatocytic cholesterol formation, resulting in up-regulation of LDL receptors and, ultimately, lowering levels of serum LDL and triglycerides.Statins
  • Ultraviolet (UV) light
• Predisposing health conditions:
  • SmokingSmokingWillful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand.Interstitial Lung Diseases
  • Vitamin D deficiencyVitamin D DeficiencyA nutritional condition produced by a deficiency of vitamin D in the diet, insufficient production of vitamin D in the skin, inadequate absorption of vitamin D from the diet, or abnormal conversion of vitamin D to its bioactive metabolites. It is manifested clinically as rickets in children and osteomalacia in adults.Fat-soluble Vitamins and their Deficiencies
  • MalignancyMalignancyHemothorax

Pathophysiology

• In muscles:
  • Complement activationComplement ActivationThe sequential activation of serum complement proteins to create the complement membrane attack complex. Factors initiating complement activation include antigen-antibody complexes, microbial antigens, or cell surface polysaccharides.Systemic Lupus Erythematosus and antibody production → immune-complex deposition onto endomysialcapillariesCapillariesCapillaries are the primary structures in the circulatory system that allow the exchange of gas, nutrients, and other materials between the blood and the extracellular fluid (ECF). Capillaries are the smallest of the blood vessels. Because a capillary diameter is so small, only 1 RBC may pass through at a time.Capillaries: Histology andarteriolesArteriolesThe smallest divisions of the arteries located between the muscular arteries and the capillaries.Arteries: Histology
  • Associated with infiltration ofB lymphocytesB lymphocytesLymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.B cells: Types and Functions,dendritic cellsDendritic cellsSpecialized cells of the hematopoietic system that have branch-like extensions. They are found throughout the lymphatic system, and in non-lymphoid tissues such as skin and the epithelia of the intestinal, respiratory, and reproductive tracts. They trap and process antigens, and present them to T-cells, thereby stimulating cell-mediated immunity. They are different from the non-hematopoietic follicular dendritic cells, which have a similar morphology and immune system function, but with respect to humoral immunity (antibody production).Skin: Structure and Functions,macrophagesMacrophagesThe relatively long-lived phagocytic cell of mammalian tissues that are derived from blood monocytes. Main types are peritoneal macrophages; alveolar macrophages; histiocytes; kupffer cells of the liver; and osteoclasts. They may further differentiate within chronic inflammatory lesions to epithelioid cells or may fuse to form foreign body giant cells or langhans giant cells.Innate Immunity: Phagocytes and Antigen Presentation, andCD4 T cellsCD4+ T cellsA critical subpopulation of T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes.T cells: Types and Functions within the perivascular and perimysial space
  • InflammationInflammationInflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function.Inflammation → destruction ofcapillariesCapillariesCapillaries are the primary structures in the circulatory system that allow the exchange of gas, nutrients, and other materials between the blood and the extracellular fluid (ECF). Capillaries are the smallest of the blood vessels. Because a capillary diameter is so small, only 1 RBC may pass through at a time.Capillaries: Histology → microinfarction of muscle → muscleatrophyAtrophyDecrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes.Cellular Adaptation and degeneration
    • PerifascicularatrophyAtrophyDecrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes.Cellular Adaptation is seen initially.
    • Necrotic and degenerative fibers are late findings.
• In theskinSkinThe skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue.Skin: Structure and Functions:
  • Pathogenesis ofDMDMDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus is poorly understood.
  • Likely similar to muscle involvement
  • Results in:
    • HyperkeratosisHyperkeratosisIchthyosis Vulgaris and dyskeratosis (abnormal keratinization of cells within thestratum spinosumStratum spinosumSkin: Structure and Functions)
    • Vacuolar changes in the basal layer
    • ↑ Lymphocytic infiltrate
    • Mucin deposition

Clinical Presentation

Musculoskeletal manifestations

• Muscle weakness
  • Involves proximal muscles:
    • Deltoids
    • Hip flexors
    • NeckNeckThe part of a human or animal body connecting the head to the rest of the body.Peritonsillar Abscess flexors
  • Symmetric
  • Develops over weeks to months
  • Mainly noted when:
    • Climbing stairs
    • Brushing hair
    • Standing up from a seated position
• Muscles are rarely tender.
• MuscleatrophyAtrophyDecrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes.Cellular Adaptation may be noted.
• Non-erosivearthralgiaArthralgiaPain in the joint.Rheumatic Fever orarthritisArthritisAcute or chronic inflammation of joints.Osteoarthritis: seen in antisynthetase syndrome

Cutaneous manifestations

• HeliotroperashRashRocky Mountain Spotted Fever:
  • Pathognomonic feature
  • ErythematousrashRashRocky Mountain Spotted Fever around the uppereyelidsEyelidsEach of the upper and lower folds of skin which cover the eye when closed.Blepharitis
  • PeriorbitalPeriorbitalOrbital and Preseptal CellulitisedemaEdemaEdema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity).Edema
• Gottron’s papules:
  • Pathognomonic feature
  • Symmetric
  • Erythematous papules
  • Located on the dorsal metacarpophalangeal andinterphalangeal jointsInterphalangeal jointsHand: Anatomy
• FacialerythemaErythemaRedness of the skin produced by congestion of the capillaries. This condition may result from a variety of disease processes.Chalazion:
  • “Butterfly” pattern that mimics themalar rashMalar RashSystemic Lupus Erythematosus of lupus
  • Involves the nasolabial folds
• Gottron’s sign:
  • Erythematous macules orpatchesPatchesVitiligo
  • Often on extensor surfaces (e.g., hands, elbows, knees, and ankles)
• Photodistributed poikiloderma:
  • Hypo- andhyperpigmentationHyperpigmentationExcessive pigmentation of the skin, usually as a result of increased epidermal or dermal melanin pigmentation, hypermelanosis. Hyperpigmentation can be localized or generalized. The condition may arise from exposure to light, chemicals or other substances, or from a primary metabolic imbalance.Malassezia Fungi
  • Mildepidermal atrophyEpidermal AtrophySecondary Skin Lesions
  • TelangiectasiasTelangiectasiasAtaxia-telangiectasia
  • Involves light-exposed sites (including the scalp):
    • Shawl sign: involves the upper back, posteriorneckNeckThe part of a human or animal body connecting the head to the rest of the body.Peritonsillar Abscess, and shoulders
    • V-sign: involves the upper chest, anteriorneckNeckThe part of a human or animal body connecting the head to the rest of the body.Peritonsillar Abscess, and shoulders
    • Holster sign: involves the lateral aspects of the thighs
• Nail changes:
  • Dilated capillary loops at the proximal nailfold
  • PeriungalerythemaErythemaRedness of the skin produced by congestion of the capillaries. This condition may result from a variety of disease processes.Chalazion
  • CuticlehypertrophyHypertrophyGeneral increase in bulk of a part or organ due to cell enlargement and accumulation of fluids and secretions, not due to tumor formation, nor to an increase in the number of cells (hyperplasia).Cellular Adaptation
• Calcinosis cutisCalcinosis CutisScleroderma (common in children): deposition ofcalciumCalciumA basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Electrolytes within theskinSkinThe skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue.Skin: Structure and Functions
• “Mechanic’s hands”:
  • Hyperkeratotic eruptions over the finger pads and lateral aspects of fingers
  • Associated with antisynthetase syndrome

Systemic manifestations

• General:
  • FatigueFatigueThe state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli.Fibromyalgia
  • FeverFeverFever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin.Fever
  • Weight lossWeight lossDecrease in existing body weight.Bariatric Surgery
  • Raynaud’s phenomenon
• Respiratory:
  • Interstitial lung disease:
    • Dry coughDry CoughStrongyloidiasis
    • DyspneaDyspneaDyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary).Dyspnea
    • Bilateral crackles
    • Seen in antisynthetase syndrome
  • DiaphragmDiaphragmThe diaphragm is a large, dome-shaped muscle that separates the thoracic cavity from the abdominal cavity. The diaphragm consists of muscle fibers and a large central tendon, which is divided into right and left parts. As the primary muscle of inspiration, the diaphragm contributes 75% of the total inspiratory muscle force.Diaphragm: Anatomy and chest-wall muscle weakness:
    • Respiratory insufficiency
• GI:
  • Pharyngeal and esophageal muscle involvement:
    • DysphagiaDysphagiaDysphagia is the subjective sensation of difficulty swallowing. Symptoms can range from a complete inability to swallow, to the sensation of solids or liquids becoming “stuck.” Dysphagia is classified as either oropharyngeal or esophageal, with esophageal dysphagia having 2 sub-types: functional and mechanical.Dysphagia
    • DysphoniaDysphoniaDifficulty and/or pain in phonation or speaking.Epiglottitis
    • Gastroesophageal reflux
  • GastritisGastritisGastritis refers to inflammation of the gastric mucosa. Gastritis may occur suddenly (acute gastritis) or slowly over time (chronic gastritis). Gastritis may be asymptomatic or with symptoms, including burning abdominal pain (which either worsens or improves with eating), dyspepsia, nausea, and vomiting.Gastritis and gastric ulcers (more common in children)
• Cardiovascular:
  • Atrioventricular conduction abnormalities
  • MyocarditisMyocarditisMyocarditis is an inflammatory disease of the myocardium, which may occur alone or in association with a systemic process. There are numerous etiologies of myocarditis, but all lead to inflammation and myocyte injury, most often leading to signs and symptoms of heart failure.Myocarditis
  • Dilated cardiomyopathyDilated CardiomyopathyDilated cardiomyopathy (DCM) is the most common type of non-ischemic cardiomyopathy and a common cause of heart failure (HF). The cause may be idiopathic, familial, or secondary to a variety of underlying conditions. The disease is characterized by the enlargement of 1 or both ventricles and reduced systolic function.Dilated Cardiomyopathy

Diagnosis

Diagnostic workup

• Initial laboratory tests:
  • CBC:
    • LeukocytosisLeukocytosisA transient increase in the number of leukocytes in a body fluid.West Nile Virus
    • Thrombocytosis
  • Inflammatory markers
    • ↑Erythrocyte sedimentation rateErythrocyte Sedimentation RateSoft Tissue Abscess (ESRESRSoft Tissue Abscess)
    • ↑ CRP
  • MuscleenzymesEnzymesEnzymes are complex protein biocatalysts that accelerate chemical reactions without being consumed by them. Due to the body’s constant metabolic needs, the absence of enzymes would make life unsustainable, as reactions would occur too slowly without these molecules.Basics of Enzymes (used to monitor response to therapy)
    • ↑ CK
    • ↑AldolaseAldolaseBecker Muscular Dystrophy
    • ↑ASTASTEnzymes of the transferase class that catalyze the conversion of l-aspartate and 2-ketoglutarate to oxaloacetate and l-glutamate.Liver Function Tests andALTALTAn enzyme that catalyzes the conversion of l-alanine and 2-oxoglutarate to pyruvate and l-glutamate.Liver Function Tests
    • ↑LDHLDHOsteosarcoma
  • ANA positivity
    • Non-specific and not diagnostic
• Followed-up withmyositis-specific antibody testingMyositis-Specific Antibody TestingPolymyositis:
  • Anti-Jo-1 antibodiesAnti-Jo-1 AntibodiesPolymyositis
    • Anti-histidyl tRNA synthetase antibodyAnti-Histidyl Trna Synthetase AntibodyPolymyositis
    • Seen in antisynthetase syndrome
    • Occurs in 20%‒30% ofpatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship
  • Anti-Mi-2antibodiesAntibodiesImmunoglobulins (Igs), also known as antibodies, are glycoprotein molecules produced by plasma cells that act in immune responses by recognizing and binding particular antigens. The various Ig classes are IgG (the most abundant), IgM, IgE, IgD, and IgA, which differ in their biologic features, structure, target specificity, and distribution.Immunoglobulins: Types and Functions
    • Seen in 10% ofpatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship
    • Highly specific, but low sensitivity
  • Anti-signal recognition protein (anti-SRP)antibodiesAntibodiesImmunoglobulins (Igs), also known as antibodies, are glycoprotein molecules produced by plasma cells that act in immune responses by recognizing and binding particular antigens. The various Ig classes are IgG (the most abundant), IgM, IgE, IgD, and IgA, which differ in their biologic features, structure, target specificity, and distribution.Immunoglobulins: Types and Functions
    • Specific for inflammatory myopathies
    • Associated with severe myositis
• Additional studies if the diagnosis is unclear due to non-specific or atypical findings:
  • ElectromyographyElectromyographyRecording of the changes in electric potential of muscle by means of surface or needle electrodes.Becker Muscular Dystrophy (EMG)
    • Comprises nerve-conduction studies that includerepetitive nerve stimulationRepetitive Nerve StimulationLambert-Eaton Myasthenic Syndrome and needle examination of muscles
    • Altered in 90% of cases ofDMDMDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus
    • Can support the diagnosis, but is not diagnostic
  • Muscle biopsyMuscle BiopsyTrichinella/Trichinellosis and histopathology
    • Most accurate test to confirm the diagnosis
    • Findings: capillary injury, perifascicularatrophyAtrophyDecrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes.Cellular Adaptation andfibrosisFibrosisAny pathological condition where fibrous connective tissue invades any organ, usually as a consequence of inflammation or other injury.Bronchiolitis Obliterans, and inflammatory cell infiltrate

Evaluation of systemic manifestations

• Interstitial lung disease:
  • Chest radiography
  • Pulmonary function tests
• DysphagiaDysphagiaDysphagia is the subjective sensation of difficulty swallowing. Symptoms can range from a complete inability to swallow, to the sensation of solids or liquids becoming “stuck.” Dysphagia is classified as either oropharyngeal or esophageal, with esophageal dysphagia having 2 sub-types: functional and mechanical.Dysphagia:
  • Barium-swallow study
  • EsophagealmanometryManometryMeasurement of the pressure or tension of liquids or gases with a manometer.Achalasia
• Conduction abnormalities:ECGECGAn electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures.Electrocardiogram (ECG)
• MyocarditisMyocarditisMyocarditis is an inflammatory disease of the myocardium, which may occur alone or in association with a systemic process. There are numerous etiologies of myocarditis, but all lead to inflammation and myocyte injury, most often leading to signs and symptoms of heart failure.Myocarditis orcardiomyopathyCardiomyopathyCardiomyopathy refers to a group of myocardial diseases associated with structural changes of the heart muscles (myocardium) and impaired systolic and/or diastolic function in the absence of other heart disorders (coronary artery disease, hypertension, valvular disease, and congenital heart disease).Cardiomyopathy: Overview and Types:echocardiographyEchocardiographyUltrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic.Tricuspid Valve Atresia (TVA)

ScreeningScreeningPreoperative Care formalignancyMalignancyHemothorax

• PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship diagnosed withDMDMDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus should be evaluated for a possible underlyingmalignancyMalignancyHemothorax.
• Workup is directed based on the patient’s age andgenderGenderGender Dysphoria.
• Initial workup:
  • MammographyMammographyRadiographic examination of the breast.Breast Cancer Screening
  • Pap smearPap smearCytological preparation of cells collected from a mucosal surface and stained with Papanicolaou stain.Cervical Cancer Screening
  • ColonoscopyColonoscopyEndoscopic examination, therapy or surgery of the luminal surface of the colon.Colorectal Cancer Screening
  • CT of thorax, abdomen, andpelvisPelvisThe pelvis consists of the bony pelvic girdle, the muscular and ligamentous pelvic floor, and the pelvic cavity, which contains viscera, vessels, and multiple nerves and muscles. The pelvic girdle, composed of 2 “hip” bones and the sacrum, is a ring-like bony structure of the axial skeleton that links the vertebral column with the lower extremities.Pelvis: Anatomy
• Additional studies are ordered based on risk factors, symptoms, or an abnormal initial workup:
  • Cancer antigen 125Cancer antigen 125A carbohydrate antigen that occurs in tumors of the ovary as well as in breast, kidney, and gastrointestinal tract tumors and normal tissue. While it is tumor-associated, it is not tumor-specific and may have a protective function against particles and infectious agents at mucosal surfaces.Serum Tumor Markers (CACACondylomata acuminata are a clinical manifestation of genital HPV infection. Condylomata acuminata are described as raised, pearly, flesh-colored, papular, cauliflower-like lesions seen in the anogenital region that may cause itching, pain, or bleeding.Condylomata Acuminata (Genital Warts) 125)
  • Transvaginal ultrasoundTransvaginal UltrasoundObstetric Imaging (forpatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship at high risk ofovarian cancerOvarian cancerOvarian cancer is a malignant tumor arising from the ovarian tissue and is classified according to the type of tissue from which it originates. The 3 major types of ovarian cancer are epithelial ovarian carcinomas (EOCs), ovarian germ cell tumors (OGCTs), and sex cord-stromal tumors (SCSTs).Ovarian Cancer)
  • UpperendoscopyEndoscopyProcedures of applying endoscopes for disease diagnosis and treatment. Endoscopy involves passing an optical instrument through a small incision in the skin i.e., percutaneous; or through a natural orifice and along natural body pathways such as the digestive tract; and/or through an incision in the wall of a tubular structure or organ, i.e. Transluminal, to examine or perform surgery on the interior parts of the body.Gastroesophageal Reflux Disease (GERD) (foresophageal cancerEsophageal cancerEsophageal cancer is 1 of the most common causes of cancer-related deaths worldwide. Nearly all esophageal cancers are either adenocarcinoma (commonly affecting the distal esophagus) or squamous cell carcinoma (affecting the proximal two-thirds of the esophagus).Esophageal Cancer)
  • MRI
  • PETPETAn imaging technique that combines a positron-emission tomography (PET) scanner and a ct X ray scanner. This establishes a precise anatomic localization in the same session.Nuclear Imaging

Management

Management ofDMDMDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus is directed toward the restoration ofmuscle strengthMuscle strengthThe amount of force generated by muscle contraction. Muscle strength can be measured during isometric, isotonic, or isokinetic contraction, either manually or using a device such as a muscle strength dynamometer.Neurological Examination and minimization ofinflammationInflammationInflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function.Inflammation.

• Rheumatology consultation
• Medical therapy:
  • Systemic glucocorticoidsSystemic GlucocorticoidsGlucocorticoids (1st-line therapy):
    • Usually needed for 9–12 months
    • Slowly tapered off
    • MuscleenzymesEnzymesEnzymes are complex protein biocatalysts that accelerate chemical reactions without being consumed by them. Due to the body’s constant metabolic needs, the absence of enzymes would make life unsustainable, as reactions would occur too slowly without these molecules.Basics of Enzymes are used to monitor response to therapy.
  • ImmunosuppressantsImmunosuppressantsImmunosuppressants are a class of drugs widely used in the management of autoimmune conditions and organ transplant rejection. The general effect is dampening of the immune response.Immunosuppressants:
    • MethotrexateMethotrexateAn antineoplastic antimetabolite with immunosuppressant properties. It is an inhibitor of tetrahydrofolate dehydrogenase and prevents the formation of tetrahydrofolate, necessary for synthesis of thymidylate, an essential component of DNA.Antimetabolite Chemotherapy,azathioprineAzathioprineAn immunosuppressive agent used in combination with cyclophosphamide and hydroxychloroquine in the treatment of rheumatoid arthritis. According to the fourth annual report on carcinogens, this substance has been listed as a known carcinogen.Immunosuppressants
    • Used to reduce steroid requirements and the risk of steroid-induced complications
  • IV immunoglobulin (IVIG):
    • ForpatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship with life-threatening weaknesses (e.g., severedysphagiaDysphagiaDysphagia is the subjective sensation of difficulty swallowing. Symptoms can range from a complete inability to swallow, to the sensation of solids or liquids becoming “stuck.” Dysphagia is classified as either oropharyngeal or esophageal, with esophageal dysphagia having 2 sub-types: functional and mechanical.Dysphagia, respiratory insufficiency)
    • Provides more rapid onset of action thansteroidsSteroidsA group of polycyclic compounds closely related biochemically to terpenes. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (sterols), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus.Benign Liver Tumors
  • For recurrent or refractory disease:
    • RituximabRituximabA murine-derived monoclonal antibody and antineoplastic agent that binds specifically to the cd20 antigen and is used in the treatment of leukemia; lymphoma and rheumatoid arthritis.Immunosuppressants
    • MycophenolateMycophenolateImmunosuppressants mofetil
    • TacrolimusTacrolimusA macrolide isolated from the culture broth of a strain of streptomyces tsukubaensis that has strong immunosuppressive activity in vivo and prevents the activation of T-lymphocytes in response to antigenic or mitogenic stimulation in vitro.Immunosuppressants
• PhysiotherapyPhysiotherapySpinal Stenosis to maintain and improve muscular function
• Management of cutaneous manifestations:
  • Protective clothing and SPF protection using sunblock
  • Avoiding sunlight and UVradiationRadiationEmission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles).Osteosarcoma (tanning beds)
• Management ofdysphagiaDysphagiaDysphagia is the subjective sensation of difficulty swallowing. Symptoms can range from a complete inability to swallow, to the sensation of solids or liquids becoming “stuck.” Dysphagia is classified as either oropharyngeal or esophageal, with esophageal dysphagia having 2 sub-types: functional and mechanical.Dysphagia:
  • Speech therapySpeech TherapyTreatment for individuals with speech defects and disorders that involves counseling and use of various exercises and AIDS to help the development of new speech habits.Myotonic Dystrophies
  • Elevate the head of the bed
  • Diet modifications
  • Enteral feeding forpatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship with severedysphagiaDysphagiaDysphagia is the subjective sensation of difficulty swallowing. Symptoms can range from a complete inability to swallow, to the sensation of solids or liquids becoming “stuck.” Dysphagia is classified as either oropharyngeal or esophageal, with esophageal dysphagia having 2 sub-types: functional and mechanical.Dysphagia
• ProphylaxisProphylaxisCephalosporins (while on long-termcorticosteroidsCorticosteroidsChorioretinitis):
  • OsteoporosisOsteoporosisOsteoporosis refers to a decrease in bone mass and density leading to an increased number of fractures. There are 2 forms of osteoporosis: primary, which is commonly postmenopausal or senile; and secondary, which is a manifestation of immobilization, underlying medical disorders, or long-term use of certain medications.Osteoporosis:
    • CalciumCalciumA basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Electrolytes andvitamin DVitamin DA vitamin that includes both cholecalciferols and ergocalciferols, which have the common effect of preventing or curing rickets in animals. It can also be viewed as a hormone since it can be formed in skin by action of ultraviolet rays upon the precursors, 7-dehydrocholesterol and ergosterol, and acts on vitamin D receptors to regulate calcium in opposition to parathyroid hormone.Fat-soluble Vitamins and their Deficiencies supplementation
    • BisphosphonatesBisphosphonatesBisphosphonates are pyrophosphate analogs most well-known for treating osteoporosis by preventing bone loss. Bisphosphonates end in the suffix “-dronate” or “-dronic acid” (e.g., alendronate, risedronate, pamidronate) and bind to hydroxyapatite crystals in bone, inhibiting osteoclast-induced bone resorption.Bisphosphonates in high-riskpatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship or individuals withosteoporosisOsteoporosisOsteoporosis refers to a decrease in bone mass and density leading to an increased number of fractures. There are 2 forms of osteoporosis: primary, which is commonly postmenopausal or senile; and secondary, which is a manifestation of immobilization, underlying medical disorders, or long-term use of certain medications.Osteoporosis
  • Pneumocystis jirovecii: trimethoprim-sulfamethoxazole
  • Appropriate immunization

Complications and Prognosis

Complications

• Cardiac involvement (50% of cases):
  • Conduction abnormalities → arrhythmia
  • MyocarditisMyocarditisMyocarditis is an inflammatory disease of the myocardium, which may occur alone or in association with a systemic process. There are numerous etiologies of myocarditis, but all lead to inflammation and myocyte injury, most often leading to signs and symptoms of heart failure.Myocarditis ordilated cardiomyopathyDilated CardiomyopathyDilated cardiomyopathy (DCM) is the most common type of non-ischemic cardiomyopathy and a common cause of heart failure (HF). The cause may be idiopathic, familial, or secondary to a variety of underlying conditions. The disease is characterized by the enlargement of 1 or both ventricles and reduced systolic function.Dilated Cardiomyopathy →heart failureHeart FailureA heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction.Total Anomalous Pulmonary Venous Return (TAPVR)
  • ↑ Risk ofmyocardial infarctionMyocardial infarctionMI is ischemia and death of an area of myocardial tissue due to insufficient blood flow and oxygenation, usually from thrombus formation on a ruptured atherosclerotic plaque in the epicardial arteries. Clinical presentation is most commonly with chest pain, but women and patients with diabetes may have atypical symptoms.Myocardial Infarction
• Respiratory complications:
  • Interstitial lung disease (30% of cases) →pulmonary hypertensionPulmonary HypertensionPulmonary hypertension (PH) or pulmonary arterial hypertension (PAH) is characterized by elevated pulmonary arterial pressure, which can lead to chronic progressive right heart failure. Pulmonary hypertension is grouped into 5 categories based on etiology, which include primary PAH, and PH due to cardiac disease, lung or hypoxic disease, chronic thromboembolic disease, and multifactorial or unclear etiologies.Pulmonary Hypertension andcor pulmonaleCor PulmonaleCor pulmonale is right ventricular (RV) dysfunction caused by lung disease that results in pulmonary artery hypertension. The most common cause of cor pulmonale is chronic obstructive pulmonary disease. Dyspnea is the usual presenting symptom.Cor Pulmonale
  • Aspiration pneumoniaAspiration pneumoniaA type of lung inflammation resulting from the aspiration of food, liquid, or gastric contents into the upper respiratory tract.Pneumonia due todysphagiaDysphagiaDysphagia is the subjective sensation of difficulty swallowing. Symptoms can range from a complete inability to swallow, to the sensation of solids or liquids becoming “stuck.” Dysphagia is classified as either oropharyngeal or esophageal, with esophageal dysphagia having 2 sub-types: functional and mechanical.Dysphagia
• MalignancyMalignancyHemothorax (25% of cases):
  • PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship withDMDMDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus have a significantly ↑ risk (5–7 fold)
  • Often within the 1st year after the diagnosis ofDMDMDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus
  • Most common: lung, breast, ovarian,stomachStomachThe stomach is a muscular sac in the upper left portion of the abdomen that plays a critical role in digestion. The stomach develops from the foregut and connects the esophagus with the duodenum. Structurally, the stomach is C-shaped and forms a greater and lesser curvature and is divided grossly into regions: the cardia, fundus, body, and pylorus.Stomach: Anatomy, pancreatic,prostateProstateThe prostate is a gland in the male reproductive system. The gland surrounds the bladder neck and a portion of the urethra. The prostate is an exocrine gland that produces a weakly acidic secretion, which accounts for roughly 20% of the seminal fluid.,bladderBladderA musculomembranous sac along the urinary tract. Urine flows from the kidneys into the bladder via the ureters, and is held there until urination.Pyelonephritis and Perinephric Abscess, andcolorectal cancerColorectal cancerColorectal cancer (CRC) is the 2nd leading cause of cancer-related deaths in the United States. Colorectal cancer is a heterogeneous disease that arises from genetic and epigenetic abnormalities, with influence from environmental factors.Colorectal Cancer, and non-Hodgkin’slymphomaLymphomaA general term for various neoplastic diseases of the lymphoid tissue.Imaging of the Mediastinum
• Adverse effects of medical therapy:
  • Corticosteroid therapy:
    • OsteoporosisOsteoporosisOsteoporosis refers to a decrease in bone mass and density leading to an increased number of fractures. There are 2 forms of osteoporosis: primary, which is commonly postmenopausal or senile; and secondary, which is a manifestation of immobilization, underlying medical disorders, or long-term use of certain medications.Osteoporosis andcompressionCompressionBlunt Chest Trauma fractures
    • Insulin resistanceInsulin resistanceDiminished effectiveness of insulin in lowering blood sugar levels: requiring the use of 200 units or more of insulin per day to prevent hyperglycemia or ketosis.Diabetes Mellitus →diabetesDiabetesDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus mellitus
    • HypertensionHypertensionHypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter.Hypertension
    • Dyslipidemia
    • Weight gain
    • Growth delay in children
    • Steroid-induced myopathy
  • Immunosuppressive therapy:
    • OpportunisticinfectionsInfectionsInvasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases.Chronic Granulomatous Disease
    • Upper respiratory tractinfectionsInfectionsInvasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases.Chronic Granulomatous Disease andpneumoniaPneumoniaPneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy.Pneumonia
    • SkinSkinThe skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue.Skin: Structure and FunctionsinfectionsInfectionsInvasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases.Chronic Granulomatous Disease
    • BacteremiaBacteremiaThe presence of viable bacteria circulating in the blood. Fever, chills, tachycardia, and tachypnea are common acute manifestations of bacteremia. The majority of cases are seen in already hospitalized patients, most of whom have underlying diseases or procedures which render their bloodstreams susceptible to invasion.Glycopeptides andsepsisSepsisSystemic inflammatory response syndrome with a proven or suspected infectious etiology. When sepsis is associated with organ dysfunction distant from the site of infection, it is called severe sepsis. When sepsis is accompanied by hypotension despite adequate fluid infusion, it is called septic shock.Sepsis and Septic Shock

PrognosisPrognosisA prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations.Non-Hodgkin Lymphomas

• RelapseRelapseRelapsing Fever:
  • Occurs in the majority ofpatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship
  • May occur at any time
• Approximately 25% ofpatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship have persistent muscle weakness ordisabilityDisabilityDetermination of the degree of a physical, mental, or emotional handicap. The diagnosis is applied to legal qualification for benefits and income under disability insurance and to eligibility for social security and workman’s compensation benefits.ABCDE Assessment.
• MortalityMortalityAll deaths reported in a given population.Measures of Health Status:
  • 5-year survival rate is 75%
  • HighermortalityMortalityAll deaths reported in a given population.Measures of Health Status inpatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship > 65 years of age
  • Often secondary to:
    • Heart failureHeart FailureA heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (ventricular dysfunction), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as myocardial infarction.Total Anomalous Pulmonary Venous Return (TAPVR)
    • Interstitial lung disease
    • InfectionsInfectionsInvasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases.Chronic Granulomatous Disease (opportunistic or non-opportunistic)
    • MalignancyMalignancyHemothorax

Differential Diagnosis

• PolymyositisPolymyositisPolymyositis (PM) is an autoimmune inflammatory myopathy caused by T cell-mediated muscle injury. The etiology of PM is unclear, but there are several genetic and environmental associations. Polymyositis is most common in middle-aged women and rarely affects children.Polymyositis: an autoimmune, inflammatory myopathy due to T cell-mediated muscle injury.PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship present with symptoms similar toDMDMDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus, but lack the characteristic cutaneous manifestations. Diagnosis is based on the clinical presentation and antibody evaluation, and may be confirmed withbiopsyBiopsyRemoval and pathologic examination of specimens from the living body.Ewing Sarcoma. Management is withsystemic glucocorticoidsSystemic GlucocorticoidsGlucocorticoids, immunosuppressive medications, andscreeningScreeningPreoperative Care formalignancyMalignancyHemothorax.
• Inclusion body myositis: an inflammatory myopathy characterized by slowly progressing muscle weakness. However, the weakness is asymmetrical and involves distal muscles, especially those of the hands. On physical examination, there is significant muscleatrophyAtrophyDecrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes.Cellular Adaptation and a lack of cutaneous lesions. The diagnosis is confirmed with abiopsyBiopsyRemoval and pathologic examination of specimens from the living body.Ewing Sarcoma, which shows inclusion bodies within the muscle tissue. Inclusion body myositis is refractory tosteroidsSteroidsA group of polycyclic compounds closely related biochemically to terpenes. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (sterols), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus.Benign Liver Tumors and must be excluded in refractory cases ofDMDMDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus.
• HypothyroidismHypothyroidismHypothyroidism is a condition characterized by a deficiency of thyroid hormones. Iodine deficiency is the most common cause worldwide, but Hashimoto’s disease (autoimmune thyroiditis) is the leading cause in non-iodine-deficient regions.Hypothyroidism: a thyroid-hormone deficiency that can result from disorders of thethyroidThyroidThe thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck.Thyroid Gland: Anatomy,hypothalamusHypothalamusThe hypothalamus is a collection of various nuclei within the diencephalon in the center of the brain. The hypothalamus plays a vital role in endocrine regulation as the primary regulator of the pituitary gland, and it is the major point of integration between the central nervous and endocrine systems.Hypothalamus, orpituitaryPituitaryA small, unpaired gland situated in the sella turcica. It is connected to the hypothalamus by a short stalk which is called the infundibulum.Hormones: Overview and Types gland.Proximal muscle weaknessProximal Muscle WeaknessLambert-Eaton Myasthenic Syndrome is a common presenting complaint.PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship usually have multiple other systemic manifestations, such as cold intolerance, neuropsychiatric changes, dryskinSkinThe skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue.Skin: Structure and Functions,constipationConstipationConstipation is common and may be due to a variety of causes. Constipation is generally defined as bowel movement frequency< 3 times per week. Patients who are constipated often strain to pass hard stools. The condition is classified as primary (also known as idiopathic or functional constipation) or secondary, and as acute or chronic.Constipation, andbradycardiaBradycardiaBradyarrhythmia is a rhythm in which the heart rate is less than 60/min. Bradyarrhythmia can be physiologic, without symptoms or hemodynamic change. Pathologic bradyarrhythmia results in reduced cardiac output and hemodynamic instability causing syncope, dizziness, or dyspnea.Bradyarrhythmias.Thyroid function testsThyroid Function TestsBlood tests used to evaluate the functioning of the thyroid gland.Ion Channel Myopathy can provide the diagnosis, and management involvesthyroidThyroidThe thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck.Thyroid Gland: Anatomy hormone replacement.
• Myasthenia gravisMyasthenia GravisMyasthenia gravis (MG) is an autoimmune neuromuscular disorder characterized by weakness and fatigability of skeletal muscles caused by dysfunction/destruction of acetylcholine receptors at the neuromuscular junction. MG presents with fatigue, ptosis, diplopia, dysphagia, respiratory difficulties, and progressive weakness in the limbs, leading to difficulty in movement.Myasthenia Gravis: a condition accompanied by episodic muscle weakness and fatigability, resulting fromautoantibodiesAutoantibodiesAntibodies that react with self-antigens (autoantigens) of the organism that produced them.Blotting Techniques toacetylcholineAcetylcholineA neurotransmitter found at neuromuscular junctions, autonomic ganglia, parasympathetic effector junctions, a subset of sympathetic effector junctions, and at many sites in the central nervous system.Receptors and Neurotransmitters of the CNSreceptorsReceptorsReceptors are proteins located either on the surface of or within a cell that can bind to signaling molecules known as ligands (e.g., hormones) and cause some type of response within the cell.Receptors (AChR).Myasthenia gravisMyasthenia GravisMyasthenia gravis (MG) is an autoimmune neuromuscular disorder characterized by weakness and fatigability of skeletal muscles caused by dysfunction/destruction of acetylcholine receptors at the neuromuscular junction. MG presents with fatigue, ptosis, diplopia, dysphagia, respiratory difficulties, and progressive weakness in the limbs, leading to difficulty in movement.Myasthenia Gravis usually involves the bulbar and ocular muscles and is brought on by activity. There are no cutaneous manifestations. Diagnosis is based on the measurement of AChRantibodiesAntibodiesImmunoglobulins (Igs), also known as antibodies, are glycoprotein molecules produced by plasma cells that act in immune responses by recognizing and binding particular antigens. The various Ig classes are IgG (the most abundant), IgM, IgE, IgD, and IgA, which differ in their biologic features, structure, target specificity, and distribution.Immunoglobulins: Types and Functions, EMG, andedrophoniumEdrophoniumA rapid-onset, short-acting cholinesterase inhibitor used in cardiac arrhythmias and in the diagnosis of myasthenia gravis. It has also been used as an antidote to curare principles.Myasthenia Gravis challenge. Management is with anticholinesterases,immunosuppressantsImmunosuppressantsImmunosuppressants are a class of drugs widely used in the management of autoimmune conditions and organ transplant rejection. The general effect is dampening of the immune response.Immunosuppressants,steroidsSteroidsA group of polycyclic compounds closely related biochemically to terpenes. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (sterols), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus.Benign Liver Tumors, and IVIG.
• Cushing’s syndrome: an endocrine disorder characterized by chronic exposure to exogenous or endogenouscorticosteroidsCorticosteroidsChorioretinitis.PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship with Cushing’s syndrome may displayproximal muscle weaknessProximal Muscle WeaknessLambert-Eaton Myasthenic Syndrome due toatrophyAtrophyDecrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes.Cellular Adaptation of the gluteal and upperlegLegThe lower leg, or just “leg” in anatomical terms, is the part of the lower limb between the knee and the ankle joint. The bony structure is composed of the tibia and fibula bones, and the muscles of the leg are grouped into the anterior, lateral, and posterior compartments by extensions of fascia.Leg: Anatomy muscles. The characteristic truncalobesityObesityObesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors.Obesity, moon facing, andeasy bruisingEasy bruisingChédiak-Higashi Syndrome may also be present. Diagnosis is based on clinical history andcortisolCortisolGlucocorticoids studies. Management depends on the underlying cause.
• Systemic lupus erythematosusSystemic lupus erythematosusSystemic lupus erythematosus (SLE) is a chronic autoimmune, inflammatory condition that causes immune-complex deposition in organs, resulting in systemic manifestations. Women, particularly those of African American descent, are more commonly affected.Systemic Lupus Erythematosus: a multisystemautoimmune disorderAutoimmune DisorderSeptic Arthritis that occurs predominantly in young women. The classicmalar rashMalar RashSystemic Lupus Erythematosus is similar to that inDMDMDiabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance.Diabetes Mellitus, except for sparing of the nasolabial folds. Associated conditions includearthritisArthritisAcute or chronic inflammation of joints.Osteoarthritis, Raynaud’s phenomenon,pleuritisPleuritisPleuritis, also known as pleurisy, is an inflammation of the visceral and parietal layers of the pleural membranes of the lungs. The condition can be primary or secondary and results in sudden, sharp, and intense chest pain on inhalation and exhalation.Pleuritis, renal disease, and neuropsychiatric symptoms. Diagnosis requires meeting the clinical and serological criteria. Management is withcorticosteroidsCorticosteroidsChorioretinitis andimmunosuppressantsImmunosuppressantsImmunosuppressants are a class of drugs widely used in the management of autoimmune conditions and organ transplant rejection. The general effect is dampening of the immune response.Immunosuppressants.
• Polymyalgia rheumaticaPolymyalgia rheumaticaA syndrome in the elderly characterized by proximal joint and muscle pain, high erythrocyte sedimentation rate, and a self-limiting course. Pain is usually accompanied by evidence of an inflammatory reaction. Women are affected twice as commonly as men and caucasians more frequently than other groups. The condition is frequently associated with giant cell arteritis and some theories pose the possibility that the two diseases arise from a single etiology or even that they are the same entity.Giant Cell Arteritis: an inflammatory condition that affects adults > 55 years of age.PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship present withpainPainAn unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons.Pain: Types and Pathways and stiffness of the proximal muscles. There is no muscle weakness oratrophyAtrophyDecrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes.Cellular Adaptation. Diagnosis is clinical, and based on the determination of elevated inflammatory markers. Management is withcorticosteroidsCorticosteroidsChorioretinitis.PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship should be evaluated fortemporal arteritisTemporal arteritisGiant cell arteritis (GCA), also known as temporal arteritis, is a type of large-vessel vasculitis that predominantly affects the aorta and its major branches, with a predilection for the branches of the carotid (including the temporal artery). Giant cell arteritis is defined by inflammatory leukocytes in the vessel walls leading to reactive damage, ischemia, and necrosis.Giant Cell Arteritis.

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