Tropical sprue
Last reviewed: 23.04.2024
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Tropical sprue is an acquired disease of the gastrointestinal tract, probably infectious etiology, characterized by malabsorption and megaloblastic anemia. The diagnosis is established clinically and a biopsy of the small intestine. Treatment of tropical sprue involves the use of tetracycline and folic acid for six months.
What causes tropical sprue?
Tropical sprue is found mainly in the Caribbean, southern India and South-East Asia, affecting both indigenous people and tourists. The disease occurs rarely in tourists who are in an endemic area less than 1 month. Although the cause of the disease is not fully understood, it is assumed that it is the result of a chronic infection of the small intestine caused by toxogenous strains of intestinal bacteria. Malabsorption of folate and a deficiency of vitamin B lead to megaloblastic anemia. The incidence of tropical sprue is decreasing, possibly due to the increasing use of antibiotics for the treatment and prevention of acute traveler's diarrhea.
Symptoms of tropical sprue
Patients usually develop acute diarrhea with fever and malaise. Then comes the chronic phase of mild diarrhea, nausea, anorexia, spastic abdominal pain and rapid fatigue. Usual steatorrhea. Dysfunction and especially deficiency of folate and vitamin B 12 develop during the period from several months to several years. The patient may experience weight loss, glossitis, stomatitis and peripheral edema.
Diagnosis of the tropical sprue
Tropical sprue is suspected in people permanently residing in the endemic zone, or tourists who visited these areas, with symptoms of megaloblastic anemia and malabsorption. The final diagnosis is established with endoscopy of the upper gastrointestinal tract with a biopsy of the small intestine. Typical histological changes usually capture the entire small intestine and consist in smoothing villi with chronic infiltration of inflammatory cells of the epithelium and its own plate. Celiac disease and parasitic infection should be avoided.
Additional laboratory tests (eg, a general blood test, albumin, calcium, prothrombin time, levels of iron, folic acid and B 12 ) help evaluate the state of digestive processes. Passage of barium in the small intestine can visualize barium segmentation, dilatation of the lumen of the gut and thickening of the folds of the mucosa. Absorption of D-xylose is disrupted in more than 90% of cases. However, these tests are not specific or meaningful in the diagnosis.
[Treatment of tropical sprue
Treatment of tropical sprue includes the use of tetracycline orally 250 mg 4 times a day for 1 to 2 months, then 2 times a day for up to 6 months, depending on the severity of the disease and the effectiveness of treatment. Folic acid is prescribed at 5-10 mg, orally once a day during the first month concomitantly with vitamin B 12 intramuscularly at 1 mg weekly for several weeks. The course of megaloblastic anemia is rapidly improving, and the clinical effect comes quickly. The rest of the dietary supplement is carried out if necessary. Recurrence of tropical sprue can occur in 20% of cases. Ineffective treatment for 4 weeks suggests a different pathology.