Tropical sprue | |
---|---|
Other names | Postinfectious tropical malabsorption [1] |
Specialty | Gastroenterology |
Symptoms | Diarrhoea, abdominal pain, weight loss |
Complications | Malabsorption, anaemia |
Diagnostic method | Intestinal histology |
Differential diagnosis | Coeliac disease, environmental enteropathy |
Treatment | Antibiotics, folate replacement |
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. [1] [2] It differs significantly from coeliac sprue. It appears to be a more severe form of environmental enteropathy. [3] [4]
The illness usually starts with an attack of acute diarrhoea, fever and malaise following which, after a variable period, the patient settles into the chronic phase of diarrhoea, steatorrhoea, weight loss, anorexia, malaise, and nutritional deficiencies. [1] [2] [3] The symptoms of tropical sprue are:
Left untreated, nutrient and vitamin deficiencies may develop in patients with tropical sprue. [1] [2] These deficiencies may have these symptoms:
The cause of tropical sprue is not known. [2] It may be caused by persistent bacterial, viral, amoebal, or parasitic infections. [5] Folic acid deficiency, effects of malabsorbed fat on intestinal motility, and persistent small intestinal bacterial overgrowth may combine to cause the disorder. [6] A link between small intestinal bacterial overgrowth and tropical sprue has been proposed to be involved in the aetiology of post-infectious irritable bowel syndrome (IBS). [7] Intestinal immunologic dysfunction, including deficiencies in secretory immunoglobulin A (IgA), may predispose people to malabsorption and bacterial colonization, so tropical sprue may be triggered in susceptible individuals following an acute enteric infection. [1]
Diagnosis of tropical sprue can be complicated because many diseases have similar symptoms. The following investigation results are suggestive: [1]
Tropical sprue is largely limited to within about 30 degrees north and south of the equator. Recent travel to this region is a key factor in diagnosing this disease in residents of countries outside of that geographical region. [2]
Other conditions which can resemble tropical sprue need to be differentiated. [4] Coeliac disease (also known as coeliac sprue or gluten sensitive enteropathy), has similar symptoms to tropical sprue, with the flattening of the villi and small intestine inflammation and is caused by an autoimmune disorder in genetically susceptible individuals triggered by ingested gluten. Malabsorption can also be caused by protozoan infections, tuberculosis, HIV/AIDS, immunodeficiency, chronic pancreatitis and inflammatory bowel disease. [2] Environmental enteropathy is a less severe, subclinical condition similar to tropical sprue. [2]
Preventive measures for visitors to tropical areas where the condition exists include steps to reduce the likelihood of gastroenteritis. These may comprise using only bottled water for drinking, brushing teeth, and washing food, and avoiding fruits washed with tap water (or consuming only peeled fruits, such as bananas and oranges). Basic sanitation is necessary to reduce fecal-oral contamination and the impact of environmental enteropathy in the developing world. [2]
Once diagnosed, tropical sprue can be treated by a course of the antibiotic tetracycline or sulphamethoxazole/trimethoprim (co-trimoxazole) for 3 to 6 months. [2] [8] Supplementation of vitamins B12 and folic acid improves appetite and leads to a gain in weight. [4] [9]
The prognosis for tropical sprue may be excellent after treatment. It usually does not recur in people who get it during travel to affected regions. The recurrence rate for natives is about 20%, [2] but another study showed changes can persist for several years. [10]
Tropical sprue is common in the Caribbean, Central and South America, and India and southeast Asia. In the Caribbean, it appeared to be more common in Puerto Rico and Haiti. Epidemics in southern India have occurred. [2]
The disease was first described by William Hillary [11] in 1759 in Barbados. [12] Tropical sprue was responsible for one-sixth of all casualties sustained by the Allied forces in India and Southeast Asia during World War II. [2] The use of folic acid and vitamin B12 in the treatment of tropical sprue was promoted in the late 1940s by Dr. Tom Spies of the University of Alabama, while conducting his research in Cuba and Puerto Rico. [13] [14] [15]
Coeliac disease or celiac disease is a long-term autoimmune disorder, primarily affecting the small intestine, where individuals develop intolerance to gluten, present in foods such as wheat, rye and barley. Classic symptoms include gastrointestinal problems such as chronic diarrhoea, abdominal distention, malabsorption, loss of appetite, and among children failure to grow normally. This often begins between six months and two years of age. Non-classic symptoms are more common, especially in people older than two years. There may be mild or absent gastrointestinal symptoms, a wide number of symptoms involving any part of the body, or no obvious symptoms. Coeliac disease was first described in childhood; however, it may develop at any age. It is associated with other autoimmune diseases, such as Type 1 diabetes mellitus and Hashimoto's thyroiditis, among others.
The small intestine or small bowel is an organ in the gastrointestinal tract where most of the absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through the pancreatic duct to aid in digestion. The small intestine is about 5.5 metres long and folds many times to fit in the abdomen. Although it is longer than the large intestine, it is called the small intestine because it is narrower in diameter.
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 Crohn's disease and celiac disease. Symptoms include abdominal pain, cramping, diarrhea, dehydration, and fever. Related diseases of the gastrointestinal system include inflammation of the stomach and large intestine.
Malabsorption is a state arising from abnormality in absorption of food nutrients across the gastrointestinal (GI) tract. Impairment can be of single or multiple nutrients depending on the abnormality. This may lead to malnutrition and a variety of anaemias.
Achlorhydria and hypochlorhydria refer to states where the production of hydrochloric acid in gastric secretions of the stomach and other digestive organs is absent or low, respectively. It is associated with various other medical problems.
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, which is caused by a number of mechanisms.
The Schilling test was a medical investigation used for patients with vitamin B12 (cobalamin) deficiency. The purpose of the test was to determine how well a patient is able to absorb B12 from their intestinal tract. The test is now considered obsolete and is rarely performed, and is no longer available at many medical centers. It is named for Robert F. Schilling.
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.
Blind loop syndrome, also known as stagnant loop syndrome, is a state that occurs when the normal bacterial flora of the small intestine proliferates to numbers that cause significant derangement to the normal physiological processes of digestion and absorption. In some cases of blind loop syndrome, overgrowth of pathogenic non-commensal bacteria has also been noted. It has long been understood that from birth, and throughout life, large amounts of bacteria reside symbiotically within animal gastrointestinal tracts such as the human gastrointestinal tract. The understanding of this gut flora has even led to novel treatments for bowel irregularity that utilize so called "probiotics" or good bacteria that aid in normal digestion. The problem of blind loop syndrome arises when the bacterial colonies residing in the upper gastrointestinal tract begin to grow out of control or are altered in their makeup thereby creating a burden on the normal physiological processes occurring in the small intestine. This results in problems, among others, of: vitamin B12 deficiency, fat malabsorption and steatorrhea, fat-soluble vitamin deficiencies and intestinal wall injury.
A hydrogen breath test is used as a diagnostic tool for small intestine bacterial overgrowth and carbohydrate malabsorption, such as lactose, fructose, and sorbitol malabsorption.
Lymphangiectasia, also known as "lymphangiectasis", is a pathologic dilation of lymph vessels. When it occurs in the intestines of dogs, and more rarely humans, it causes a disease known as "intestinal lymphangiectasia". This disease is characterized by lymphatic vessel dilation, chronic diarrhea and loss of proteins such as serum albumin and globulin. It is considered to be a chronic form of protein-losing enteropathy.
Radiation enteropathy is a syndrome that may develop following abdominal or pelvic radiation therapy for cancer. Many affected people are cancer survivors who had treatment for cervical cancer or prostate cancer; it has also been termed pelvic radiation disease with radiation proctitis being one of the principal features.
Gluten-sensitive enteropathy–associated conditions are comorbidities or complications of gluten-related gastrointestinal distress. GSE has key symptoms typically restricted to the bowel and associated tissues; however, there are a wide variety of associated conditions. These include bowel disorders, eosinophilic gastroenteritis and increase with coeliac disease (CD) severity. With some early onset and a large percentage of late onset disease, other disorders appear prior to the coeliac diagnosis or allergic-like responses markedly increased in GSE. Many of these disorders persist on a strict gluten-free diet, and are thus independent of coeliac disease after triggering. For example, autoimmune thyroiditis is a common finding with GSE.
Jejunoileal bypass (JIB) was a surgical weight-loss procedure performed for the relief of morbid obesity from the 1950s through the 1970s in which all but 30 cm (12 in) to 45 cm (18 in) of the small bowel were detached and set to the side.
SeHCAT is a drug used in a clinical test to diagnose bile acid malabsorption.
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.
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.
Environmental enteropathy is an acquired small intestinal disorder characterized by gut inflammation, reduced absorptive surface area in small intestine, and disruption of intestinal barrier function. EE is most common amongst children living in low-resource settings. Acute symptoms are typically minimal or absent. EE can lead to malnutrition, anemia, Stunted growth, impaired brain development, and impaired response to oral vaccinations.
Duodenal lymphocytosis, sometimes called lymphocytic duodenitis, lymphocytic duodenosis, or duodenal intraepithelial lymphocytosis, is a condition where an increased number of intra-epithelial lymphocytes is seen in biopsies of the duodenal mucosa when these are examined microscopically. This form of lymphocytosis is often a feature of coeliac disease but may be found in other disorders.