# Whipple Disease and Tropical Sprue > Whipple disease and tropical sprue for NEET-PG Medicine: Tropheryma whipplei, PAS-positive macrophages, antibiotic regimens and malabsorption differences. - Canonical URL: https://prepelephant.com/topics/neet-pg/medicine/whipple-disease-and-tropical-sprue - Exam / course: NEET-PG · Subject: Medicine - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-08 - Last updated: 2026-10-08 - Reference basis: Harrison's Principles of Internal Medicine; Sleisenger and Fordtran's Gastrointestinal and Liver Disease; Robbins and Cotran Pathologic Basis of Disease - How to cite: "Whipple Disease and Tropical Sprue", PrepElephant, https://prepelephant.com/topics/neet-pg/medicine/whipple-disease-and-tropical-sprue ## Direct answer Whipple disease is a systemic infection caused by the bacterium Tropheryma whipplei, producing malabsorption, arthralgia and fever, and it is diagnosed by PAS-positive macrophages in a small bowel biopsy. Tropical sprue is a malabsorption disorder of unclear cause that affects people living in endemic regions, and it responds to tetracycline and folic acid. The two must be separated because their treatments differ completely. ## What you must remember - **Tropheryma whipplei:** A Gram-positive actinomycete-like bacterium causing Whipple disease, classically in middle-aged men with arthralgia, weight loss and diarrhoea. - **PAS-positive macrophages:** Diastase-resistant, PAS-positive macrophages in the duodenal lamina propria are the classic biopsy finding; PCR confirms the organism. - **Neurological Whipple:** Oculomasticatory myorhythmia and cognitive decline; it needs longer and CNS-directed therapy. - **Whipple treatment:** Intravenous ceftriaxone for about two weeks, then oral co-trimoxazole for at least a year. - **Tropical sprue:** Diarrhoea, steatorrhoea and macrocytic anaemia from folate deficiency after prolonged residence in the tropics. - **Tropical sprue treatment:** Tetracycline with folic acid for several months; a gluten-free diet is not required. ## A pathway for a middle-aged man with arthritis and diarrhoea A 52-year-old man has migratory arthralgia, weight loss, steatorrhoea and occasional fever over a year, and he has been treated for rheumatoid arthritis without benefit. 1. **Recognise the combination:** Arthritis with bowel symptoms broadens the differential beyond rheumatological disease. 2. **Biopsy the duodenum:** Periodic acid-Schiff staining shows PAS-positive, diastase-resistant macrophages in the lamina propria. 3. **Confirm the organism:** Immunohistochemistry or PCR for Tropheryma whipplei confirms the diagnosis. 4. **Check for organ involvement:** Whipple disease can affect the brain and heart, so a lumbar puncture or echocardiography is considered if symptoms suggest it. 5. **Start treatment:** Intravenous ceftriaxone is given for about two weeks, followed by oral co-trimoxazole for at least a year. Stopping early is the classic reason for relapse, so the course is completed with clinical and laboratory follow-up. 6. **Reconsider if the biopsy differs:** Villous atrophy without PAS-positive macrophages would point to coeliac disease or tropical sprue, and the work-up would change accordingly. ## Where the exam tries to catch you Whipple disease and tropical sprue share malabsorption, but the stain and the antibiotic response separate them. - **Trap:** Confusing Whipple disease with tropical sprue because both cause malabsorption. — **Correct:** Both can show villous changes, so the decisive tests are the PAS stain and the antibiotic response. - **Trap:** Treating Whipple disease with a short antibiotic course. — **Correct:** The regimen is long, and co-trimoxazole maintenance is mandatory to prevent relapse. - **Trap:** Diagnosing tropical sprue without excluding coeliac disease. — **Correct:** Coeliac disease is excluded with anti-tissue transglutaminase antibodies and a gluten history, since tropical sprue is gluten-independent. Giardiasis and bacterial overgrowth are separated by stool testing and breath tests. - **Trap:** Overlooking the folate link in tropical sprue. — **Correct:** Folate deficiency causes the macrocytic anaemia of tropical sprue, a common detail examiners ask about. ## Frequently asked questions ### What is the characteristic duodenal biopsy finding in Whipple disease? Duodenal biopsy in Whipple disease shows PAS-positive, diastase-resistant macrophages in the lamina propria, which contain the bacterium. PCR for Tropheryma whipplei can confirm the diagnosis from biopsy, cerebrospinal fluid or other samples. ### What antibiotic regimen treats classic Whipple disease? Classic Whipple disease is treated with intravenous ceftriaxone for about two weeks, followed by oral co-trimoxazole for at least a year. Neurological Whipple disease requires longer treatment with CNS-directed therapy. ### How does tropical sprue differ from coeliac disease in management? Tropical sprue responds to tetracycline and folic acid and does not require a gluten-free diet, while coeliac disease needs lifelong gluten avoidance. Anti-tissue transglutaminase antibodies are positive in coeliac disease but not in tropical sprue. ### What causes macrocytic anaemia in tropical sprue? Macrocytic anaemia in tropical sprue is usually due to folate deficiency from malabsorption in the proximal small intestine. Folic acid supplementation corrects the anaemia and forms part of standard therapy. ### Which neurological finding is characteristic of Whipple disease? Oculomasticatory myorhythmia, a rhythmic movement of the eyes, face and jaw, is a characteristic neurological finding in Whipple disease. Cognitive decline and supranuclear gaze palsy may also occur.