Diarrhea | |
---|---|
Other names | Diarrhoea (or diarrhœa) |
An electron micrograph of rotavirus, the cause of nearly 40% of hospitalizations from diarrhea in children under five [1] | |
Specialty | Infectious disease, gastroenterology |
Symptoms | Loose frequent bowel movements, dehydration [2] |
Causes | Usually infection (viral, bacterial, parasitic) [2] |
Risk factors | Contaminated food or water [2] |
Prevention | Handwashing, rotavirus vaccination, breastfeeding [2] |
Treatment | Oral rehydration solution, zinc supplementation [2] |
Frequency | ≈2.4 billion (2015) [3] |
Deaths | 1.53 million (2019) [4] |
Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. [2] It often lasts for a few days and can result in dehydration due to fluid loss. [2] Signs of dehydration often begin with loss of the normal stretchiness of the skin and irritable behaviour. [2] This can progress to decreased urination, loss of skin color, a fast heart rate, and a decrease in responsiveness as it becomes more severe. [2] Loose but non-watery stools in babies who are exclusively breastfed, however, are normal. [2]
The most common cause is an infection of the intestines due to a virus, bacterium, or parasite—a condition also known as gastroenteritis. [2] These infections are often acquired from food or water that has been contaminated by feces, or directly from another person who is infected. [2] The three types of diarrhea are: short duration watery diarrhea, short duration bloody diarrhea, and persistent diarrhea (lasting more than two weeks, which can be either watery or bloody). [2] The short duration watery diarrhea may be due to cholera, although this is rare in the developed world. [2] If blood is present, it is also known as dysentery. [2] A number of non-infectious causes can result in diarrhea. [5] These include lactose intolerance, irritable bowel syndrome, non-celiac gluten sensitivity, celiac disease, inflammatory bowel disease such as ulcerative colitis, hyperthyroidism, bile acid diarrhea, and a number of medications. [5] [6] [7] In most cases, stool cultures to confirm the exact cause are not required. [8]
Diarrhea can be prevented by improved sanitation, clean drinking water, and hand washing with soap. [2] Breastfeeding for at least six months and vaccination against rotavirus is also recommended. [2] Oral rehydration solution (ORS)—clean water with modest amounts of salts and sugar—is the treatment of choice. [2] Zinc tablets are also recommended. [2] These treatments have been estimated to have saved 50 million children in the past 25 years. [1] When people have diarrhea it is recommended that they continue to eat healthy food, and babies continue to be breastfed. [2] If commercial ORS is not available, homemade solutions may be used. [9] In those with severe dehydration, intravenous fluids may be required. [2] Most cases, however, can be managed well with fluids by mouth. [10] Antibiotics, while rarely used, may be recommended in a few cases such as those who have bloody diarrhea and a high fever, those with severe diarrhea following travelling, and those who grow specific bacteria or parasites in their stool. [8] Loperamide may help decrease the number of bowel movements but is not recommended in those with severe disease. [8]
About 1.7 to 5 billion cases of diarrhea occur per year. [2] [5] [11] It is most common in developing countries, where young children get diarrhea on average three times a year. [2] Total deaths from diarrhea are estimated at 1.53 million in 2019—down from 2.9 million in 1990. [4] In 2012, it was the second most common cause of deaths in children younger than five (0.76 million or 11%). [2] [12] Frequent episodes of diarrhea are also a common cause of malnutrition and the most common cause in those younger than five years of age. [2] Other long term problems that can result include stunted growth and poor intellectual development. [12]
The word diarrhea is from the Ancient Greek διάρροια from διάdia "through" and ῥέωrheo "flow".
Diarrhea is the spelling in American English, whereas diarrhoea is the spelling in British English.
Slang terms for the condition include "the runs", "the squirts" (or "squits" in Britain [13] ) and "the trots". [14] [15]
The word is often pronounced as /ˌdaɪəˈriːə/ DY-ə-REE-ə.
Diarrhea is defined by the World Health Organization as having three or more loose or liquid stools per day, or as having more stools than is normal for that person. [2]
Acute diarrhea is defined as an abnormally frequent discharge of semisolid or fluid fecal matter from the bowel, lasting less than 14 days, by World Gastroenterology Organization. [16] Acute diarrhea that is watery may be known as AWD (Acute Watery Diarrhoea.) [17]
Secretory diarrhea means that there is an increase in the active secretion, or there is an inhibition of absorption. There is little to no structural damage. The most common cause of this type of diarrhea is a cholera toxin that stimulates the secretion of anions, especially chloride ions (Cl–). Therefore, to maintain a charge balance in the gastrointestinal tract, sodium (Na+) is carried with it, along with water. In this type of diarrhea intestinal fluid secretion is isotonic with plasma even during fasting. [18] [19] It continues even when there is no oral food intake.
Osmotic diarrhea occurs when too much water is drawn into the bowels. If a person drinks solutions with excessive sugar or excessive salt, these can draw water from the body into the bowel and cause osmotic diarrhea. [20] [19] Osmotic diarrhea can also result from maldigestion (e.g., pancreatic disease or coeliac disease) in which the nutrients are left in the lumen to pull in water. Or it can be caused by osmotic laxatives (which work to alleviate constipation by drawing water into the bowels). In healthy individuals, too much magnesium, vitamin C or undigested lactose can produce osmotic diarrhea and distention of the bowel. A person who has lactose intolerance can have difficulty absorbing lactose after an extraordinarily high intake of dairy products. In persons who have fructose malabsorption, excess fructose intake can also cause diarrhea. High-fructose foods that also have a high glucose content are more absorbable and less likely to cause diarrhea. Sugar alcohols such as sorbitol (often found in sugar-free foods) are difficult for the body to absorb and, in large amounts, may lead to osmotic diarrhea. [18] In most of these cases, osmotic diarrhea stops when the offending agent (e.g., milk or sorbitol) is stopped.
Exudative diarrhea occurs with the presence of blood and pus in the stool. This occurs with inflammatory bowel diseases, such as Crohn's disease or ulcerative colitis, and other severe infections such as E. coli or other forms of food poisoning. [19] [18]
Inflammatory diarrhea occurs when there is damage to the mucosal lining or brush border, which leads to a passive loss of protein-rich fluids and a decreased ability to absorb these lost fluids. Features of all three of the other types of diarrhea can be found in this type of diarrhea. [21] It can be caused by bacterial infections, viral infections, parasitic infections, or autoimmune problems such as inflammatory bowel diseases. It can also be caused by tuberculosis, colon cancer, and enteritis. [19]
If there is blood visible in the stools, it is also known as dysentery. The blood is a trace of an invasion of bowel tissue. Dysentery is a symptom of, among others, Shigella , Entamoeba histolytica , and Salmonella . [19]
Diarrheal disease may have a negative impact on both physical fitness and mental development. "Early childhood malnutrition resulting from any cause reduces physical fitness and work productivity in adults", [22] and diarrhea is a primary cause of childhood malnutrition. [23] Further, evidence suggests that diarrheal disease has significant impacts on mental development and health; it has been shown that, even when controlling for helminth infection and early breastfeeding, children who had experienced severe diarrhea had significantly lower scores on a series of tests of intelligence. [22] [24]
Diarrhea can cause electrolyte imbalances, kidney impairment, dehydration, and defective immune system responses. When oral drugs are administered, the efficiency of the drug is to produce a therapeutic effect and the lack of this effect may be due to the medication travelling too quickly through the digestive system, limiting the time that it can be absorbed. Clinicians try to treat the diarrheas by reducing the dosage of medication, changing the dosing schedule, discontinuation of the drug, and rehydration. The interventions to control the diarrhea are not often effective. Diarrhea can have a profound effect on the quality of life because fecal incontinence is one of the leading factors for placing older adults in long term care facilities (nursing homes). [19]
In the latter stages of human digestion, ingested materials are inundated with water and digestive fluids such as gastric acid, bile, and digestive enzymes in order to break them down into their nutrient components, which are then absorbed into the bloodstream via the intestinal tract in the small intestine. Prior to defecation, the large intestine reabsorbs the water and other digestive solvents in the waste product in order to maintain proper hydration and overall equilibrium. [25] Diarrhea occurs when the large intestine is prevented, for any number of reasons, from sufficiently absorbing the water or other digestive fluids from fecal matter, resulting in a liquid, or "loose", bowel movement. [26]
Acute diarrhea is most commonly due to viral gastroenteritis with rotavirus, which accounts for 40% of cases in children under five. [1] In travelers, however, bacterial infections predominate. [27] Various toxins such as mushroom poisoning and drugs can also cause acute diarrhea.
Chronic diarrhea can be the part of the presentations of a number of chronic medical conditions affecting the intestine. Common causes include ulcerative colitis, Crohn's disease, microscopic colitis, celiac disease, irritable bowel syndrome, and bile acid malabsorption. [28]
There are many causes of infectious diarrhea, which include viruses, bacteria and parasites. [29] Infectious diarrhea is frequently referred to as gastroenteritis. [30] Norovirus is the most common cause of viral diarrhea in adults, [31] but rotavirus is the most common cause in children under five years old. [32] Adenovirus types 40 and 41, [33] and astroviruses cause a significant number of infections. [34] Shiga-toxin producing Escherichia coli, such as E coli o157:h7, are the most common cause of infectious bloody diarrhea in the United States. [35]
Campylobacter spp. are a common cause of bacterial diarrhea, but infections by Salmonella spp., Shigella spp. and some strains of Escherichia coli are also a frequent cause. [36]
In the elderly, particularly those who have been treated with antibiotics for unrelated infections, a toxin produced by Clostridioides difficile often causes severe diarrhea. [37]
Parasites, particularly protozoa e.g., Cryptosporidium spp., Giardia spp., Entamoeba histolytica , Blastocystis spp., Cyclospora cayetanensis , are frequently the cause of diarrhea that involves chronic infection. The broad-spectrum antiparasitic agent nitazoxanide has shown efficacy against many diarrhea-causing parasites. [38]
Other infectious agents, such as parasites or bacterial toxins, may exacerbate symptoms. [27] In sanitary living conditions where there is ample food and a supply of clean water, an otherwise healthy person usually recovers from viral infections in a few days. However, for ill or malnourished individuals, diarrhea can lead to severe dehydration and can become life-threatening. [39]
Open defecation is a leading cause of infectious diarrhea leading to death. [40]
Poverty is a good indicator of the rate of infectious diarrhea in a population. This association does not stem from poverty itself, but rather from the conditions under which impoverished people live. The absence of certain resources compromises the ability of the poor to defend themselves against infectious diarrhea. "Poverty is associated with poor housing, crowding, dirt floors, lack of access to clean water or to sanitary disposal of fecal waste (sanitation), cohabitation with domestic animals that may carry human pathogens, and a lack of refrigerated storage for food, all of which increase the frequency of diarrhea ... Poverty also restricts the ability to provide age-appropriate, nutritionally balanced diets or to modify diets when diarrhea develops so as to mitigate and repair nutrient losses. The impact is exacerbated by the lack of adequate, available, and affordable medical care." [41]
One of the most common causes of infectious diarrhea is a lack of clean water. Often, improper fecal disposal leads to contamination of groundwater. This can lead to widespread infection among a population, especially in the absence of water filtration or purification. Human feces contains a variety of potentially harmful human pathogens. [42]
Proper nutrition is important for health and functioning, including the prevention of infectious diarrhea. It is especially important to young children who do not have a fully developed immune system. Zinc deficiency, a condition often found in children in developing countries can, even in mild cases, have a significant impact on the development and proper functioning of the human immune system. [43] [44] Indeed, this relationship between zinc deficiency and reduced immune functioning corresponds with an increased severity of infectious diarrhea. Children who have lowered levels of zinc have a greater number of instances of diarrhea, severe diarrhea, and diarrhea associated with fever. [45] Similarly, vitamin A deficiency can cause an increase in the severity of diarrheal episodes. However, there is some discrepancy when it comes to the impact of vitamin A deficiency on the rate of disease. While some argue that a relationship does not exist between the rate of disease and vitamin A status, [46] others suggest an increase in the rate associated with deficiency. [47] Given that estimates suggest 127 million preschool children worldwide are vitamin A deficient, this population has the potential for increased risk of disease contraction. [48]
Malabsorption is the inability to absorb food fully, mostly from disorders in the small bowel, but also due to maldigestion from diseases of the pancreas.
Causes include:[ citation needed ]
The two overlapping types here are of unknown origin:
Another possible cause of diarrhea is irritable bowel syndrome (IBS), which usually presents with abdominal discomfort relieved by defecation and unusual stool (diarrhea or constipation) for at least three days a week over the previous three months. [49] Symptoms of diarrhea-predominant IBS can be managed through a combination of dietary changes, soluble fiber supplements and medications such as loperamide or codeine. About 30% of patients with diarrhea-predominant IBS have bile acid malabsorption diagnosed with an abnormal SeHCAT test. [50]
Diarrhea can be caused by other diseases and conditions, namely:
Over 700 medications, such as penicillin, are known to cause diarrhea. [53] [54] The classes of medications that are known to cause diarrhea are laxatives, antacids, heartburn medications, antibiotics, anti-neoplastic drugs, anti-inflammatories as well as many dietary supplements. [19]
Function | Transporter |
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Absorption | NHE, SGLT1, ENaC, DRA |
Secretion | CaCC, NKCC1, CFTR |
Absorption and secretion | Sodium potassium ATPase |
According to two researchers, Nesse and Williams, diarrhea may function as an evolved expulsion defense mechanism. As a result, if it is stopped, there might be a delay in recovery. [56] They cite in support of this argument research published in 1973 that found that treating Shigella with the anti-diarrhea drug (Co-phenotrope, Lomotil) caused people to stay feverish twice as long as those not so treated. The researchers indeed themselves observed that: "Lomotil may be contraindicated in shigellosis. Diarrhea may represent a defense mechanism". [57]
The following types of diarrhea may indicate further investigation is needed:
A severity score is used to aid diagnosis in children. [58]
When diarrhea lasts for more than four weeks a number of further tests may be recommended including: [59]
A 2019 guideline recommended that testing for ova and parasites was only needed in people who are at high risk though they recommend routine testing for giardia. [60] Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were not recommended. [60]
Worldwide in 2004, approximately 2.5 billion cases of diarrhea occurred, which resulted in 1.5 million deaths among children under the age of five. [1] Greater than half of these were in Africa and South Asia. [1] This is down from a death rate of 4.5 million in 1980 for gastroenteritis. [62] Diarrhea remains the second leading cause of infant mortality (16%) after pneumonia (17%) in this age group. [1]
The majority of such cases occur in the developing world, with over half of the recorded cases of childhood diarrhea occurring in Africa and Asia, with 696 million and 1.2 billion cases, respectively, compared to only 480 million in the rest of the world. [63]
Infectious diarrhea resulted in about 0.7 million deaths in children under five years old in 2011 and 250 million lost school days. [64] [65] In the Americas, diarrheal disease accounts for a total of 10% of deaths among children aged 1–59 months while in South East Asia, it accounts for 31.3% of deaths. [66] It is estimated that around 21% of child mortalities in developing countries are due to diarrheal disease. [67]
The World Health Organization has reported that "deaths due to diarrhoeal diseases have dropped by 45%, from sixth leading cause of death in 2000 to thirteenth in 2021." [68]
Even though diarrhea is best known in humans, it affects many other species, notably among primates. [69] The cecal appendix, when present, appears to afford some protection against diarrhea to young primates. [70]
Numerous studies have shown that improvements in drinking water and sanitation (WASH) lead to decreased risks of diarrhoea. [71] Such improvements might include for example use of water filters, provision of high-quality piped water and sewer connections. [71]
In institutions, communities, and households, interventions that promote hand washing with soap lead to significant reductions in the incidence of diarrhea. [72] The same applies to preventing open defecation at a community-wide level and providing access to improved sanitation. [64] [73] This includes use of toilets and implementation of the entire sanitation chain connected to the toilets (collection, transport, disposal or reuse of human excreta).
There is limited evidence that safe disposal of child or adult feces can prevent diarrheal disease. [74] [75]
Basic sanitation techniques can have a profound effect on the transmission of diarrheal disease. The implementation of hand washing using soap and water, for example, has been experimentally shown to reduce the incidence of disease by approximately 30–48%. [76] [77] [72] Hand washing in developing countries, however, is compromised by poverty as acknowledged by the CDC: "Handwashing is integral to disease prevention in all parts of the world; however, access to soap and water is limited in a number of less developed countries. This lack of access is one of many challenges to proper hygiene in less developed countries." Solutions to this barrier require the implementation of educational programs that encourage sanitary behaviours. [78]
Given that water contamination is a major means of transmitting diarrheal disease, efforts to provide clean water supply and improved sanitation have the potential to dramatically cut the rate of disease incidence. In fact, it has been proposed that we might expect an 88% reduction in child mortality resulting from diarrheal disease as a result of improved water sanitation and hygiene. [42] [79] Similarly, a meta-analysis of numerous studies on improving water supply and sanitation shows a 22–27% reduction in disease incidence, and a 21–30% reduction in mortality rate associated with diarrheal disease. [80]
Chlorine treatment of water, for example, has been shown to reduce both the risk of diarrheal disease, and of contamination of stored water with diarrheal pathogens. [81]
Immunization against the pathogens that cause diarrheal disease is a viable prevention strategy, however it does require targeting certain pathogens for vaccination. In the case of Rotavirus, which was responsible for around 6% of diarrheal episodes and 20% of diarrheal disease deaths in the children of developing countries, use of a Rotavirus vaccine in trials in 1985 yielded a slight (2–3%) decrease in total diarrheal disease incidence, while reducing overall mortality by 6–10%. Similarly, a Cholera vaccine showed a strong reduction in morbidity and mortality, though the overall impact of vaccination was minimal as Cholera is not one of the major causative pathogens of diarrheal disease. [82] Since this time, more effective vaccines have been developed that have the potential to save many thousands of lives in developing nations, while reducing the overall cost of treatment, and the costs to society. [83] [84]
Rotavirus vaccine decreases the rates of diarrhea in a population. [1] [85] New vaccines against rotavirus, Shigella, Enterotoxigenic Escherichia coli (ETEC), and cholera are under development, as well as other causes of infectious diarrhea.[ medical citation needed ]
Dietary deficiencies in developing countries can be combated by promoting better eating practices. Zinc supplementation proved successful showing a significant decrease in the incidence of diarrheal disease compared to a control group. [86] [87] The majority of the literature suggests that vitamin A supplementation is advantageous in reducing disease incidence. [88] Development of a supplementation strategy should take into consideration the fact that vitamin A supplementation was less effective in reducing diarrhea incidence when compared to vitamin A and zinc supplementation, and that the latter strategy was estimated to be significantly more cost effective. [89]
Breastfeeding practices have been shown to have a dramatic effect on the incidence of diarrheal disease in poor populations. Studies across a number of developing nations have shown that those who receive exclusive breastfeeding during their first 6 months of life are better protected against infection with diarrheal diseases. [90] One study in Brazil found that non-breastfed infants were 14 times more likely to die from diarrhea than exclusively breastfed infants. [91] Exclusive breastfeeding is currently recommended for the first six months of an infant's life by the WHO, [92] [93] with continued breastfeeding until at least two years of age. [93]
Probiotics decrease the risk of diarrhea in those taking antibiotics. [94] Insecticide spraying may reduce fly numbers and the risk of diarrhea in children in a setting where there is seasonal variations in fly numbers throughout the year. [95]
In many cases of diarrhea, replacing lost fluid and salts is the only treatment needed. This is usually by mouth – oral rehydration therapy – or, in severe cases, intravenously. [1] Diet restrictions such as the BRAT diet are no longer recommended. [96] Research does not support the limiting of milk to children as doing so has no effect on duration of diarrhea. [97] To the contrary, WHO recommends that children with diarrhea continue to eat as sufficient nutrients are usually still absorbed to support continued growth and weight gain, and that continuing to eat also speeds up recovery of normal intestinal functioning. [20] CDC recommends that children and adults with cholera also continue to eat. [98] There is no evidence that early refeeding in children can cause an increase in inappropriate use of intravenous fluid, episodes of vomiting, and risk of having persistent diarrhea. [99]
Medications such as loperamide (Imodium) and bismuth subsalicylate may be beneficial; however they may be contraindicated in certain situations. [100]
Oral rehydration solution (ORS) (a slightly sweetened and salty water) can be used to prevent dehydration. Standard home solutions such as salted rice water, salted yogurt drinks, vegetable and chicken soups with salt can be given. Home solutions such as water in which cereal has been cooked, unsalted soup, green coconut water, weak tea (unsweetened), and unsweetened fresh fruit juices can have from half a teaspoon to full teaspoon of salt (from one-and-a-half to three grams) added per liter. Clean plain water can also be one of several fluids given. [20] There are commercial solutions such as Pedialyte, and relief agencies such as UNICEF widely distribute packets of salts and sugar. A WHO publication for physicians recommends a homemade ORS consisting of one liter water with one teaspoon salt (3 grams) and two tablespoons sugar (18 grams) added [20] (approximately the "taste of tears" [101] ). Rehydration Project recommends adding the same amount of sugar but only one-half a teaspoon of salt, stating that this more dilute approach is less risky with very little loss of effectiveness. [102] Both agree that drinks with too much sugar or salt can make dehydration worse. [20] [102]
Appropriate amounts of supplemental zinc and potassium should be added if available. But the availability of these should not delay rehydration. As WHO points out, the most important thing is to begin preventing dehydration as early as possible. [20] In another example of prompt ORS hopefully preventing dehydration, CDC recommends for the treatment of cholera continuing to give Oral Rehydration Solution during travel to medical treatment. [98]
Vomiting often occurs during the first hour or two of treatment with ORS, especially if a child drinks the solution too quickly, but this seldom prevents successful rehydration since most of the fluid is still absorbed. WHO recommends that if a child vomits, to wait five or ten minutes and then start to give the solution again more slowly. [20]
Drinks especially high in simple sugars, such as soft drinks and fruit juices, are not recommended in children under five as they may increase dehydration. A too rich solution in the gut draws water from the rest of the body, just as if the person were to drink sea water. [20] [103] Plain water may be used if more specific and effective ORT preparations are unavailable or are not palatable. [103] Additionally, a mix of both plain water and drinks perhaps too rich in sugar and salt can alternatively be given to the same person, with the goal of providing a medium amount of sodium overall. [20] A nasogastric tube can be used in young children to administer fluids if warranted. [104]
The WHO recommends a child with diarrhea continue to be fed. Continued feeding speeds the recovery of normal intestinal function. In contrast, children whose food is restricted have diarrhea of longer duration and recover intestinal function more slowly. The WHO states "Food should never be withheld and the child's usual foods should not be diluted. Breastfeeding should always be continued." [20] In the specific example of cholera, the CDC makes the same recommendation. [98] Breast-fed infants with diarrhea often choose to breastfeed more, and should be encouraged to do so. [20] In young children who are not breast-fed and live in the developed world, a lactose-free diet may be useful to speed recovery. [105] Eating food containing soluble fibre may help, but insoluble fibre might make it worse. [106]
Antidiarrheal agents can be classified into four different groups: antimotility, antisecretory, adsorbent, and anti-infectious. [107] While antibiotics are beneficial in certain types of acute diarrhea, they are usually not used except in specific situations. [108] [109] There are concerns that antibiotics may increase the risk of hemolytic uremic syndrome in people infected with Escherichia coli O157:H7. [110] In resource-poor countries, treatment with antibiotics may be beneficial. [109] However, some bacteria are developing antibiotic resistance, particularly Shigella. [111] Antibiotics can also cause diarrhea, and antibiotic-associated diarrhea is the most common adverse effect of treatment with general antibiotics.
While bismuth compounds (Pepto-Bismol) decreased the number of bowel movements in those with travelers' diarrhea, they do not decrease the length of illness. [112] Anti-motility agents like loperamide are also effective at reducing the number of stools but not the duration of disease. [8] These agents should be used only if bloody diarrhea is not present. [113]
Diosmectite, a natural aluminomagnesium silicate clay, is effective in alleviating symptoms of acute diarrhea in children, [114] and also has some effects in chronic functional diarrhea, radiation-induced diarrhea, and chemotherapy-induced diarrhea. [52] Another absorbent agent used for the treatment of mild diarrhea is kaopectate.
Racecadotril an antisecretory medication may be used to treat diarrhea in children and adults. [107] It has better tolerability than loperamide, as it causes less constipation and flatulence. [115] However, it has little benefit in improving acute diarrhea in children. [116]
Bile acid sequestrants such as cholestyramine can be effective in chronic diarrhea due to bile acid malabsorption. Therapeutic trials of these drugs are indicated in chronic diarrhea if bile acid malabsorption cannot be diagnosed with a specific test, such as SeHCAT retention. [117]
Zinc supplementation may benefit children over six months old with diarrhea in areas with high rates of malnourishment or zinc deficiency. [118] This supports the World Health Organization guidelines for zinc, but not in the very young.
A Cochrane Review from 2020 concludes that probiotics make little or no difference to people who have diarrhea lasting 2 days or longer and that there is no proof that they reduce its duration. [119] The probiotic lactobacillus can help prevent antibiotic-associated diarrhea in adults but possibly not children. [120] For those with lactose intolerance, taking digestive enzymes containing lactase when consuming dairy products often improves symptoms.
Cholera is an infection of the small intestine by some strains of the bacterium Vibrio cholerae. Symptoms may range from none, to mild, to severe. The classic symptom is large amounts of watery diarrhea lasting a few days. Vomiting and muscle cramps may also occur. Diarrhea can be so severe that it leads within hours to severe dehydration and electrolyte imbalance. This may result in sunken eyes, cold skin, decreased skin elasticity, and wrinkling of the hands and feet. Dehydration can cause the skin to turn bluish. Symptoms start two hours to five days after exposure.
Rotaviruses are the most common cause of diarrhoeal disease among infants and young children. Nearly every child in the world is infected with a rotavirus at least once by the age of five. Immunity develops with each infection, so subsequent infections are less severe. Adults are rarely affected. Rotavirus is a genus of double-stranded RNA viruses in the family Reoviridae. There are nine species of the genus, referred to as A, B, C, D, F, G, H, I and J. Rotavirus A is the most common species, and these rotaviruses cause more than 90% of rotavirus infections in humans.
Giardiasis is a parasitic disease caused by Giardia duodenalis. Infected individuals who experience symptoms may have diarrhea, abdominal pain, and weight loss. Less common symptoms include vomiting and blood in the stool. Symptoms usually begin one to three weeks after exposure and, without treatment, may last two to six weeks or longer.
Enteritis is inflammation of the small intestine. It is most commonly caused by food or drink contaminated with pathogenic microbes, such as Serratia, but may have other causes such as NSAIDs, radiation therapy as well as autoimmune conditions like coeliac disease. Symptoms include abdominal pain, cramping, diarrhoea, dehydration, and fever. Related diseases of the gastrointestinal system involve inflammation of the stomach and large intestine.
Gastroenteritis, also known as infectious diarrhea, is an inflammation of the gastrointestinal tract including the stomach and intestine. Symptoms may include diarrhea, vomiting, and abdominal pain. Fever, lack of energy, and dehydration may also occur. This typically lasts less than two weeks. Although it is not related to influenza, in the U.S. and U.K., it is sometimes called the "stomach flu".
Travelers' diarrhea (TD) is a stomach and intestinal infection. TD is defined as the passage of unformed stool while traveling. It may be accompanied by abdominal cramps, nausea, fever, headache and bloating. Occasionally dysentery may occur. Most travelers recover within three to four days with little or no treatment. About 12% of people may have symptoms for a week.
Gastrointestinal diseases refer to diseases involving the gastrointestinal tract, namely the esophagus, stomach, small intestine, large intestine and rectum; and the accessory organs of digestion, the liver, gallbladder, and pancreas.
Small intestinal bacterial overgrowth (SIBO), also termed bacterial overgrowth, or small bowel bacterial overgrowth syndrome (SBBOS), is a disorder of excessive bacterial growth in the small intestine. Unlike the colon, which is rich with bacteria, the small bowel usually has fewer than 100,000 organisms per millilitre. Patients with bacterial overgrowth typically develop symptoms which may include nausea, bloating, vomiting, diarrhea, malnutrition, weight loss, and malabsorption by various mechanisms.
Tropical sprue is a malabsorption disease commonly found in tropical regions, marked with abnormal flattening of the villi and inflammation of the lining of the small intestine. It differs significantly from coeliac sprue. It appears to be a more severe form of environmental enteropathy.
Short bowel syndrome is a rare malabsorption disorder caused by a lack of functional small intestine. The primary symptom is diarrhea, which can result in dehydration, malnutrition, and weight loss. Other symptoms may include bloating, heartburn, feeling tired, lactose intolerance, and foul-smelling stool. Complications can include anemia and kidney stones.
Oral rehydration therapy (ORT) is a type of fluid replacement used to prevent and treat dehydration, especially due to diarrhea. It involves drinking water with modest amounts of sugar and salts, specifically sodium and potassium. Oral rehydration therapy can also be given by a nasogastric tube. Therapy can include the use of zinc supplements to reduce the duration of diarrhea in infants and children under the age of 5. Use of oral rehydration therapy has been estimated to decrease the risk of death from diarrhea by up to 93%.
Colestyramine (INN) or cholestyramine (USAN) is a bile acid sequestrant, which binds bile in the gastrointestinal tract to prevent its reabsorption. It is a strong ion exchange resin, which means it can exchange its chloride anions with anionic bile acids in the gastrointestinal tract and bind them strongly in the resin matrix. The functional group of the anion exchange resin is a quaternary ammonium group attached to an inert styrene-divinylbenzene copolymer.
Enterotoxigenic Escherichia coli (ETEC) is a type of Escherichia coli and one of the leading bacterial causes of diarrhea in the developing world, as well as the most common cause of travelers' diarrhea. Insufficient data exists, but conservative estimates suggest that each year, about 157,000 deaths occur, mostly in children, from ETEC. A number of pathogenic isolates are termed ETEC, but the main hallmarks of this type of bacterium are expression of one or more enterotoxins and presence of fimbriae used for attachment to host intestinal cells. The bacterium was identified by the Bradley Sack lab in Kolkata in 1968.
Rifaximin, is a non-absorbable, broad spectrum antibiotic mainly used to treat travelers' diarrhea. It is based on the rifamycin antibiotics family. Since its approval in Italy in 1987, it has been licensed in over more than 30 countries for the treatment of a variety of gastrointestinal diseases like irritable bowel syndrome, and hepatic encephalopathy. It acts by inhibiting RNA synthesis in susceptible bacteria by binding to the RNA polymerase enzyme. This binding blocks translocation, which stops transcription. It is marketed under the brand name Xifaxan by Salix Pharmaceuticals.
Antibiotic-associated diarrhea (AAD) results from an imbalance in the colonic microbiota caused by antibiotics. Microbiotal alteration changes carbohydrate metabolism with decreased short-chain fatty acid absorption and an osmotic diarrhea as a result. Another consequence of antibiotic therapy leading to diarrhea is an overgrowth of potentially pathogenic organisms such as Clostridioides difficile. It is defined as frequent loose and watery stools with no other complications.
Chronic diarrheaof infancy, also called toddler's diarrhea, is a common condition typically affecting up to 1.7 billion children between ages 6–30 months worldwide every year, usually resolving by age 4. According to the World Health Organization (WHO), diarrheal disease is the second greatest cause of death in children 5 years and younger. Diarrheal disease takes the lives of 525,000 or more children per year. Diarrhea is characterized as the condition of passing of three or more loose or watery bowel movements within a day sometimes with undigested food visible. Diarrhea is separated into three clinical categories; acute diarrhea may last multiple hours or days, acute bloody diarrhea, also known as dysentery, and finally, chronic or persistent diarrhea which lasts 2–4 weeks or more. There is normal growth with no evidence of malnutrition in the child experiencing persistent diarrhea. In chronic diarrhea there is no evidence of blood in the stool and there is no sign of infection. The condition may be related to irritable bowel syndrome. There are various tests that can be performed to rule out other causes of diarrhea that don't fall under the chronic criteria, including blood test, colonoscopy, and even genetic testing. Most acute or severe cases of diarrhea have treatment guidelines revolving around prescription or non prescription medications based on the cause, but the treatment protocols for chronic diarrhea focus on replenishing the body with lost fluids and electrolytes, because there typically isn't a treatable cause.
Probiotics are live microorganisms promoted with claims that they provide health benefits when consumed, generally by improving or restoring the gut flora. Probiotics are considered generally safe to consume, but may cause bacteria-host interactions and unwanted side effects in rare cases. There is little evidence that probiotics bring the health benefits claimed for them.
Bile acid malabsorption (BAM), known also as bile acid diarrhea, is a cause of several gut-related problems, the main one being chronic diarrhea. It has also been called bile acid-induced diarrhea, cholerheic or choleretic enteropathy, bile salt diarrhea or bile salt malabsorption. It can result from malabsorption secondary to gastrointestinal disease, or be a primary disorder, associated with excessive bile acid production. Treatment with bile acid sequestrants is often effective. Depending on the severity of symptoms, it may be recognised as a disability in the United Kingdom under the Equality Act 2010.
Dehydration can occur as a result of diarrhea, vomiting, water scarcity, physical activity, and alcohol consumption. Management of dehydration seeks to reverse dehydration by replenishing the lost water and electrolytes. Water and electrolytes can be given through a number of routes, including oral, intravenous, and rectal.
Clostridioides difficile is a bacterium known for causing serious diarrheal infections, and may also cause colon cancer. It is known also as C. difficile, or C. diff, and is a Gram-positive species of spore-forming bacteria. Clostridioides spp. are anaerobic, motile bacteria, ubiquitous in nature and especially prevalent in soil. Its vegetative cells are rod-shaped, pleomorphic, and occur in pairs or short chains. Under the microscope, they appear as long, irregular cells with a bulge at their terminal ends. Under Gram staining, C. difficile cells are Gram-positive and show optimum growth on blood agar at human body temperatures in the absence of oxygen. C. difficile is catalase- and superoxide dismutase-negative, and produces up to three types of toxins: enterotoxin A, cytotoxin B and Clostridioides difficile transferase. Under stress conditions, the bacteria produce spores that are able to tolerate extreme conditions that the active bacteria cannot tolerate.