Giardiasis with protein-losing enteropathy: diagnosis by fecal alpha 1-antitrypsin determination.

Giardia lamblia infection was documented by jejunal biopsy in a previously healthy 2-year-old boy with acute onset of hypoproteinemia due to protein-losing enteropathy. All symptoms and abnormal laboratory findings resolved with anti-Giardia therapy. This is only the second case report of giardiasis with documented protein-losing enteropathy. Further application of the fecal alpha 1-antitrypsin assay may help to clarify the relationship between Giardia infection and protein-losing enteropathy and its role in development of malnutrition.