Spectrum of chronic small bowel diarrhea with malabsorption in Indian subcontinent: is the trend really changing?

Background/aims: This study aimed to document the recent etiological spectrum of chronic diarrhea with malabsorption and also to compare features that differentiate tropical sprue from parasitic infections, the two most common etiologies of malabsorption in the tropics.

Methods: We analyzed 203 consecutive patients with malabsorption. The etiological spectrum and factors that differentiated tropical sprue from parasitic infections were analyzed.

Results: The most common etiology was tropical sprue (n=98, 48.3%) followed by parasitic infections (n=25, 12.3%) and tuberculosis (n=22, 10.8%). Other causes were immunodeficiency (n=15, 7.3%; 12 with human immunodeficiency virus and 3 with hypogammaglobulinemia), celiac disease (n=11, 5.4%), Crohn's disease (n=11, 5.4%), small intestinal bacterial overgrowth (n=11, 5.4%), hyperthyroidism (n=4, 1.9%), diabetic diarrhea (n=4, 1.9%), systemic lupus erythematosus (n=3, 1.4%), metastatic carcinoid (n=1, 0.5%) and Burkitt's lymphoma (n=1, 0.5%). On multivariate analysis, features that best differentiated tropical sprue from parasitic infections were larger stool volume (P=0.009), severe weight loss (P=0.02), knuckle hyperpigmentation (P=0.008), low serum B12 levels (P=0.05), high mean corpuscular volume (P=0.003), reduced height or scalloping of the duodenal folds on endoscopy (P=0.003) and villous atrophy on histology (P=0.04). Presence of upper gastrointestinal (GI) symptoms like bloating, nausea and vomiting predicted parasitic infections (P=0.01).

Conclusions: Tropical sprue and parasitic infections still dominate the spectrum of malabsorption in India. Severe symptoms and florid malabsorption indicate tropical sprue while the presence of upper GI symptoms indicates parasitic infections.