Terminology

What is dermatology?

Definition

Dermatology is the medical discipline that is concerned with the diagnosis and treatment of diseases of the skin,hair, andnails in both children and adults. Specialists in dermatology are calleddermatologists.

The New Zealand Dermatological Society’s definition is comprehensive:

“Dermatology involves but is not limited to study, research, and diagnosis of normal and disorders, diseases, cancers, cosmetic and ageing conditions of the skin, fat, hair, nails and oral andgenital membranes, and the management of these by different investigations and therapies, including but not limited to dermatohistopathology,topical andsystemic medications, dermatologic surgery and dermatologic cosmetic surgery, immunotherapy, phototherapy,laser therapy,radiotherapy andphotodynamic therapy.”

How many people get skin disease?

The skin is the largest and most visible organ of the body. It reflects the health of the body and acts as a barrier against injury andbacteria.

Skin disorders are the fourth most frequent cause of all human disease, affecting between 30–70% of people worldwide. Most peopledevelop some type of skin disease during their life, from infants to the elderly, and this is one of the leading reasons to seek medical advice in all societies.

What are the different fields of dermatology?

There are many fields and subspecialties within dermatology, including (but not limited to):

• Medical dermatology – includes dealing with medical conditions such asdermatitis,psoriasis,urticaria,connective tissue diseases,skin infections, disorders ofpigmentation, skin conditions associated with internal diseases, andacne androsacea in both adults and children (paediatric dermatology).
• Surgical dermatology – deals mostly with treating and removing skinlesions such asmelanoma, non-melanomaskin cancer (NMSC), and othernon-cancerous lesions by a variety of modalities includingcurettage and cautery,cryotherapy,excisional surgery andphotodynamic therapy. This field also includesMohs micrographic surgery.
• Cosmetic dermatology – focusing on the cosmetic treatment of skin, hair, andnail conditions. This includeslaser treatments, removal of scars,hair implants,injectable fillers, andbotulinum toxin (Botox).

What are the most common skin disorders?

Common skin diseases include:

• Skin cancer
• Warts
• Skin infections:fungal,viral (eg,herpes simplex), andbacterial
• Dermatitis — one in six children developatopic dermatitis (eczema)
• Psoriasis
• Acne — a common condition affecting adolescents worldwide
• Hand dermatitis — resulting from external contact with detergents and household chemicals, affects most homemakers with young families
• Alopecia (hair loss) –autoimmune disease that affects 2% of people worldwide.

Dermatological examinations and procedures

SeeDermatological investigations and tests for more detail.

Dermoscopy

Adermatoscope is a handheld medical device that employs a magnification illuminated lens system that assists in the identification and diagnosis of skin lesions.

Microbiology samples

A swab can be taken from skin lesions withexudate or fluid to be examined forviral andbacterial cultures.

Skin scraping

A sample ofscaly skin can be taken by scraping a disposable scalpel blade 90 degrees to the skin to collect surface dead skin cells forfungal examination.

Skin biopsy

This includes removal of a skin sample from thelesion of interest to be sent forhistopathological examination. It is performed underlocal anaesthesia. There are different methods for taking askin biopsy – including a shavebiopsy,punch biopsy, orexcision biopsy. It is useful in diagnosing many skin diseases includingskin cancers andblistering skin conditions.

Intralesional steroid injection

Theinjection of steroids into the skin is used in the management of different conditions such ashypertrophic or keloid scars,acne cysts,vitiligo, andalopecia.

Phototherapy

This includes using narrow band ultraviolet (UV) radiation in treating various skin conditions such aseczema (atopic dermatitis),psoriasis,vitiligo, andpruritus.

Research in dermatology

Research is an important component of dermatology, leading to many advances in the field and improved patient outcomes. Manydermatologists are involved in research, at both basic science and clinical levels.

Bibliography

• Flohr C, Hay R. Putting the burden of skin diseases on the global map. Br J Dermatol. 2021;184 Supp 2:189-90. doi: 10.1111/bjd.19704.Journal
• New Zealand Dermatological Society Inc. What is a Dermatologist? What is Dermatology? 2021. Accessed 2023.Available here
• Richard MA, Paul C, Nijsten T, et al. Prevalence of most common skin diseases in Europe: a population‐based study. J Eur Acad Dermatol Venereol. 2022;36(7):1088-96. doi: 10.1111/jdv.18050.Journal

On DermNet

• What is a dermatologist?
• Terminology in dermatology
• Dermatological investigations and tests
• The role of surgery in dermatology
• Dermatopathology
• Ethnic dermatology
• Forensic dermatology
• Teledermatology
• Useful dermatology resources for health professionals
• Worldwide dermatology links for doctors
• Medical journals for the dermatologist
• Worldwide dermatology societies
• Dermatology conferences
• Worldwide dermatology links for patients

Other websites

• Dermatology basics: the fundamentals of diagnosis and history taking — DermNet e-lecture [YouTube]
• New Zealand Dermatological Society Inc.
• The Australasian College of Dermatologists
• American Academy of Dermatology Association
• The British Association of Dermatologists

Books

• Gawkrodger D, Ardern-Jones MR. Dermatology: An Illustrated Colour Text. 6th ed. Elsevier; 2017.

Books about skin diseases

• Books about the skin
• Dermatology Made Easy - second edition