Bone marrow involvement in Whipple's disease: rarely reported, but really rare?

Infection with Tropheryma whippelii, the causative agent of Whipple's disease, involves nearly every organ. Involvement of bone marrow may be an overlooked area of Whipple's disease. We report a case of lymphoma-like Whipple's disease with bone marrow involvement together with a brief review of the literature on this topic. Despite minimal documentation, bone marrow may be commonly involved in Whipple's disease and, although not specific, diastase-resistant periodic acid-Schiff (PAS)-positive macrophages in bone marrow may offer an important clue to diagnosis using PAS histology of upper endoscopic biopsies, polymerase chain reaction or electron microscopy.