What's on this Page
What is Tropical sprue?
- Tropical sprue is a malabsorption syndrome occurring primarily in tropical regions, including Puerto Rico, India, and Southeast Asia.
- The clinical features of tropical sprue include anorexia, diarrhea, weight loss, abdominal pain, and steatorrhea; these symptoms can develop in expatriates even several months after returning to temperate regions.
Synonyms
Postinfectious tropical malabsorption
“Tropical enteropathy,” referring to a subclinical form of tropical sprue.
Epidemiology & Demographics
How common is Tropical sprue?
- Tropical sprue is endemic in tropical regions of Venezuela, Colombia, the Middle East, the Far East, the Caribbean (Puerto Rico, Haiti, Dominican Republic, Cuba), and India.
- The disease affects mainly adults, although it has been reported in all age groups.
What are the Physical Findings & Clinical Presentation
- The classic clinical features of tropical sprue are nonspecific and simply reflect the symptom of malabsorption. Onset is generally not insidious, and most patients can pinpoint when their disorder began.
- Diffuse, nonspecific abdominal tenderness and distention. Abdominal pain is crampy in nature.
- Low-grade fever.
- Glossitis, cheilosis, hyperkeratosis, hyperpigmentation.
- Diarrhea, often with mucus and foul-smelling stools from fat malabsorption.
- Nausea, which leads to decreased appetite and decreased oral intake.
- Lactose intolerance often develops early in the course of tropical sprue.
Differential Diagnosis
- Celiac disease
- Parasitic infestation
- Inflammatory bowel disease
- Other causes of malabsorption (e.g., Whipple disease)
- Lymphoma
- Pancreatic tumor
- Intestinal tuberculosis
- Microsporidia-associated HIV enteropathy
How is this condition diagnosed?
- Diagnostic workup includes a comprehensive history (especially travel history), physical examination, laboratory evidence of malabsorption (see the following), and jejunal biopsy; the biopsy results are nonspecific, with blunting, atrophy, and even disappearance of the villi and subepithelial lymphocytic infiltration.
- Partial villus atrophy distinguishes tropical sprue histologically from celiac sprue, which reveals flattened mucosa.
What are the Laboratory Tests?
- Megaloblastic anemia (>50% of cases)
- Vitamin B 12 deficiency, folate deficiency
- Abnormal D-xylose absorption (72-hr fecal fat determination or serum carotene concentration)
- Stool examination to exclude Giardia spp.
Imaging Studies
GI series with small-bowel follow-through may reveal coarsening of the jejunal folds.
How is Tropical sprue treated?
Nonpharmacologic Therapy
Monitoring of weight and calorie intake
Acute General Treatment
- Folic acid therapy (5 mg bid for 2 wk followed by a maintenance dose of 1 mg tid) will improve anemia and malabsorption in more than two thirds of patients
- Doxycycline 100 mg PO bid or tetracycline 250 mg qid for 4 to 6 wk in individuals who have returned to temperate zones, up to 6 mo in patients in endemic areas; ampicillin 500 mg bid for at least 4 wk in patients intolerant to doxycycline or tetracycline
- Correction of vitamin B 12 deficiency: Vitamin B 12 1000 mcg IM weekly for 4 wk, then monthly for 3 to 6 mo
- •Correction of other nutritional deficiencies (e.g., calcium, iron)
Disposition
Complete recovery with appropriate therapy
Referral
GI referral for jejunal biopsy
Pearls & Considerations
Comments
- Tropical sprue should be considered in any patient who presents with chronic diarrhea, weight loss, and malabsorption, especially if there is significant travel and exposure history.
- Important factors in the medical history in addition to travel history are use of medications that may predispose to a small-bowel overgrowth, HIV exposure (increased risk of chronic diarrhea), and any surgical procedure that may predispose to blind loop syndrome.
- Most of the functional changes in tropical sprue may be related to small-bowel mucosal damage; however, there is also dysfunctional hormonal regulation of the gut (increased enteroglucagon and motilin levels, decreased postprandial insulin and gastric inhibitory peptide), and decreased ability of the colon to absorb water.
- Even with prolonged therapy, relapses can occur; however, some may be attributable to reexposure to an infecting organism rather than relapsing disease.
