The cause of dysentery is usually the bacteria from genusShigella, in which case it is known asshigellosis, or the amoebaEntamoeba histolytica; then it is calledamoebiasis.[1] Other causes may include certain chemicals, other bacteria, other protozoa, orparasitic worms.[2] It may spread between people.[4] Risk factors include contamination of food and water withfeces due to poorsanitation.[5] The underlying mechanism involvesinflammation of theintestine, especially of thecolon.[2]
Efforts to prevent dysentery includehand washing andfood safety measures while traveling in countries of high risk.[4] While the condition generally resolves on its own within a week, drinking sufficient fluids such asoral rehydration solution is important.[4] Antibiotics such asazithromycin may be used to treat cases associated with travelling in thedeveloping world.[11] While medications used to decrease diarrhea such asloperamide are not recommended on their own, they may be used together with antibiotics.[11][4]
Shigella results in about 165 million cases of diarrhea and 1.1 million deaths a year with nearly all cases in the developing world.[6] In areas with poor sanitation nearly half of cases of diarrhea are due toEntamoeba histolytica.[5]Entamoeba histolytica affects millions of people and results in more than 55,000 deaths a year.[12] It commonly occurs in less developed areas of Central and South America, Africa, and Asia.[12] Dysentery has been described at least since the time ofHippocrates.[13]
The most common form of dysentery is bacillary dysentery, which is typically a mild sickness, causing symptoms normally consisting of mild abdominal pains and frequent passage of loose stools or diarrhea. Symptoms normally present themselves after 1–3 days, and are usually no longer present after a week. The frequency of urges to defecate, the large volume of liquid feces ejected, and the presence of blood, mucus, or pus depends on thepathogen causing the disease. Temporarylactose intolerance can occur, as well. In some occasions, severe abdominal cramps,fever,shock, anddelirium can all be symptoms.[2][14][15][16]
In extreme cases, people may pass more than one liter of fluid per hour. More often, individuals will complain ofdiarrhea withblood, accompanied by extreme abdominal pain,rectal pain and a low-gradefever. Rapid weight loss andmuscle aches sometimes also accompany dysentery, whilenausea andvomiting are rare.
Cross-section of diseased intestines. Colored lithographc. 1843
Dysentery results frombacterial orparasitic infections. Viruses do not generally cause the disease.[10] These pathogens typically reach thelarge intestine after entering orally, through ingestion of contaminated food or water, oral contact with contaminated objects or hands, and so on. Each specific pathogen has its own mechanism or pathogenesis, but in general, the result is damage to the intestinal linings, leading to theinflammatory immune responses. This can causeelevated physical temperature, painful spasms of the intestinal muscles (cramping), swelling due to fluid leaking from capillaries of the intestine (edema) and further tissue damage by the body's immune cells and the chemicals, calledcytokines, which are released to fight the infection. The result can be impaired nutrient absorption, excessive water and mineral loss through the stools due to breakdown of the control mechanisms in the intestinal tissue that normally remove water from the stools, and in severe cases, the entry of pathogenic organisms into the bloodstream.Anemia may also arise due to the blood loss through diarrhea.[citation needed]
Bacterial infections that cause bloody diarrhea are typically classified as being either invasive or toxogenic. Invasive species cause damage directly by invading into the mucosa. The toxogenic species do not invade, but cause cellular damage by secreting toxins, resulting in bloody diarrhea. This is also in contrast to toxins that cause watery diarrhea, which usually do not cause cellular damage, but rather they take over cellular machinery for a portion of life of the cell.[18]
Definitions of dysentery can vary by region and by medical specialty. The U. S. Centers for Disease Control and Prevention (CDC) limits its definition to "diarrhea with visible blood".[19] Others define the term more broadly.[20] These differences in definition must be taken into account when defining mechanisms. For example, using the CDC definition requires that intestinal tissue be so severely damaged that blood vessels have ruptured, allowing visible quantities of blood to be lost with defecation. Other definitions require less specific damage.[citation needed]
When amoebae inside the bowel of an infected person are ready to leave the body, they group together and form a shell that surrounds and protects them. This group of amoebae is known as a cyst, which is then passed out of the person's body in the feces and can survive outside the body. If hygiene standards are poor – for example, if the person does not dispose of the feces hygienically – then it can contaminate the surroundings, such as nearby food and water.If another person then eats or drinks food or water that has been contaminated with feces containing the cyst, that person will also become infected with the amoebae. Amoebic dysentery is particularly common in parts of the world where human feces are used as fertilizer.After entering the person's body through the mouth, the cyst travels down into the stomach. The amoebae inside the cyst are protected from the stomach's digestive acid. From the stomach, the cyst travels to the intestines, where it breaks open and releases the amoebae, causing the infection. The amoebae can burrow into the walls of the intestines and cause small abscesses and ulcers to form. The cycle then begins again.[citation needed]
Dysentery may also be caused byshigellosis, an infection bybacteria of the genusShigella, and is then known as bacillary dysentery (or Marlow syndrome). The termbacillary dysentery etymologically might seem to refer to any dysentery caused by anybacilliform bacteria, but its meaning is restricted by convention toShigella dysentery.[citation needed]
A diagnosis may be made by taking a history and doing a brief examination. Dysentery should not be confused withhematochezia, which is the passage of fresh blood through the anus, usually in or with stools.[24]
Cultures ofstool samples are examined to identify the organism causing dysentery. Usually, several samples must be obtained due to the number of amoebae, which changes daily.[17]Blood tests can be used to measure abnormalities in the levels of essentialminerals and salts.[17]
Although there is currently no vaccine that protects againstShigella infection, several are in development.[25][26] Vaccination may eventually become a part of the strategy to reduce the incidence and severity of diarrhea, particularly among children in low-resource settings. For example,Shigella is a longstanding World Health Organization (WHO) target for vaccine development, and sharp declines in age-specific diarrhea/dysentery attack rates for this pathogen indicate that natural immunity does develop following exposure; thus, vaccination to prevent this disease should be feasible. The development of vaccines against these types of infection has been hampered by technical constraints, insufficient support for coordination, and a lack of market forces for research and development. Most vaccine development efforts are taking place in the public sector or as research programs within biotechnology companies.[citation needed]
Dysentery is managed by maintaining fluids usingoral rehydration therapy.[4] If this treatment cannot be adequately maintained due to vomiting or the profuseness of diarrhea, hospital admission may be required forintravenous fluid replacement. In ideal situations, no antimicrobial therapy should be administered until microbiological microscopy and culture studies have established the specific infection involved. When laboratory services are not available, it may be necessary to administer a combination of drugs, including anamoebicidal drug to kill theparasite, and anantibiotic to treat any associated bacterial infection.[citation needed]Laudanum (Deodorized Tincture of Opium) may be used for severe pain and to combat severe diarrhea.[citation needed]
If shigellosis is suspected and it is not too severe, letting it run its course may be reasonable – usually less than a week. If the case is severe, antibiotics such asciprofloxacin orTMP-SMX may be useful. However, many strains ofShigella are becoming resistant to common antibiotics, and effective medications are often in short supply in developing countries. If necessary, a doctor may have to reserve antibiotics for those at highest risk for death, including young children, people over 50, and anyone suffering from dehydration or malnutrition.[citation needed]
With correct treatment, most cases of amoebic and bacterial dysentery subside within 10 days, and most individuals achieve a full recovery within two to four weeks after beginning proper treatment. If the disease is left untreated, the prognosis varies with the immune status of the individual patient and the severity of disease. Extreme dehydration can delay recovery and significantly raises the risk for serious complications including death.[28]
Insufficient data exists, butShigella is estimated to have caused the death of 34,000 children under the age of five in 2013, and 40,000 deaths in people over five years of age.[25] Amoebiasis infects over 50 million people each year, of whom 50,000 die (one per thousand).[29]
Shigella evolved with the human expansion out of Africa 50,000 to 200,000 years ago.[30]
The seed, leaves, and bark of thekapok tree have been used in traditional medicines by indigenous peoples of the rainforest regions in the Americas, west-central Africa, and Southeast Asia in the treatment of this disease.[31][32][33]
In 1915, AustralianbacteriologistFannie Eleanor Williams was serving as a medic in Greece with theAustralian Imperial Force, receiving casualties directly fromGallipoli. In Gallipoli, dysentery was severely affecting soldiers and causing significant loss of manpower. Williams carried outserological investigations into dysentery, co-authoring several groundbreaking papers with SirCharles Martin, director of theLister Institute.[34] The result of their work into dysentery was increased demand for specificdiagnostics and curative sera.[35]
Bacillus subtilis was marketed throughout America and Europe from 1946 as an immunostimulatory aid in the treatment of gut and urinary tract diseases such as rotavirus andShigella,[36] but declined in popularity after the introduction of consumer antibiotics.
ARed Army soldier dies of dysentery after eating unwashed vegetables. This is a common way of contracting dysentery. From a health advisory pamphlet given to soldiers.
580: Childesinda, son ofChilperic I, Frankish king, died of dysentery as a child
580:Austregilde, Frankish queen, died of dysentery. According toGregory of Tours she blamed her doctors for her death and asked her husband, KingGuntram, to have the doctors executed after she died, which he did.[37]
1270:Louis IX of France died of dysentery inTunis while commanding his troops for theEighth Crusade on 25 August 1270.
1307:Edward I of England caught dysentery on his way to the Scottish border and died in his servants' arms on 7 July 1307.
1322:Philip V of France died of dysentery at theAbbey of Longchamp (site of the present hippodrome in theBois de Boulogne) in Paris while visiting his daughter, Blanche, who had taken her vows as a nun there in 1322. He died on 3 January 1322.
1376:Edward the Black Prince, son of Edward III of England and heir to the English throne. Died of apparent dysentery in June, after a months-long period of illness during which he predicted his own imminent death, in his 46th year.
1605:Akbar, ruler of the Mughal Empire of South Asia, died of dysentery. On 3 October 1605, he fell ill with an attack of dysentery, from which he never recovered. He is believed to have died on or about 27 October 1605, after which his body was buried ina mausoleum inAgra, present-dayIndia.[42]
1675:Jacques Marquette died of dysentery on his way north from what is today Chicago, traveling to the mission where he intended to spend the rest of his life.[43]
1676:Nathaniel Bacon died of dysentery after taking control of Virginia followingBacon's Rebellion. He is believed to have died in October 1676, allowing Virginia's ruling elite to regain control.[44]
1680:Shivaji, founder and ruler of theMaratha Empire of South Asia, died of dysentery on 3 April 1680. In 1680, Shivaji fell ill with fever and dysentery, dying around 3–5 April 1680 at the age of 52 on the eve ofHanuman Jayanti. He was cremated atRaigad Fort, where hisSamadhi is built inMahad, Raigad district of Maharashtra, India.[45][46]
1910:Luo Yixiu, first wife ofMao Zedong, died of dysentery on 11 February 1910. She was 20 years old.[50]
1912: HistorianArnold J. Toynbee contracted dysentery on April 26, 1912, from contaminated water in the Peloponnese; the malady led to his being excused from military service inWorld War I.[51]
1930: The French explorer and writerMichel Vieuchange died of dysentery inAgadir on 30 November 1930, on his return from the "forbidden city" ofSmara. He was nursed by his brother, DoctorJean Vieuchange, who was unable to save him. The notebooks and photographs, edited by Jean Vieuchange, went on to become bestsellers.[52][53]
1942: TheSelarang Barracks incident in the summer of 1942 duringWorld War II involved the forced crowding of 17,000Anglo-Australianprisoners-of-war (POWs) by theirJapanese captors in the areas around the barracks square for nearly five days with little water and no sanitation after the Selarang Barracks POWs refused to sign a pledge not to escape. The incident ended with the surrender of the Australian commanders due to the spreading of dysentery among their men.[54]
^DuPont HL (September 1978). "Interventions in diarrheas of infants and young children".Journal of the American Veterinary Medical Association.173 (5 Pt 2):649–53.PMID359524.
^Ryan J (2016).Boards and Beyond: Infectious Disease: A Companion Book to the Boards and Beyond Website (Version 9-26-2016 ed.). CreateSpace Independent Publishing Platform.ISBN978-1-5237-0935-9.
^Morris DR (1998).The washing of the spears: a history of the rise of the Zulu nation under Shaka and its fall in the Zulu War of 1879 (1st ed.). New York: Da Capo Press.ISBN978-0-306-80866-1.
^Thompson P (2005).The Battle For Singapore—The True Story of the Greatest Catastrophe of World War II. United Kingdom: Portraits Books. pp. 389–390.ISBN978-0-7499-5085-9.{{cite book}}: CS1 maint: publisher location (link)
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