Contributed by Michael Torbenson, MD, James Hanchett, MD, and Sheldon Bastacky, MD
Published on line in March 1998
The patient is a 32 year old normotensive, non-diabetic male with no significant past medical history. He developed recurrent fevers of unknown origin which appeared to wax and wane independent of antibiotic treatment. Over a period of several months, an extensive work up was performed which was essentially negative, including an echocardiogram to rule out endocarditis, a bone scan to rule out occult infection, a chest radiograph, computed tomography (CT) scans of the head, sinuses, abdomen, and pelvis, and multiple blood cultures. The following tests were also negative: HIV, PPD, RPR, ANA, rheumatoid factor, Monospot, and lyme titers. Serological tests showed only IgG positivity for CMV and EBV. A pyelogram showed only a filling defect due to an enlarged prostate.
The patient had enlarged, non-tender, bilateral lymphadenopathy in the groin. A lymph node from the right groin was biopsied and showed small non-caseating granulomas. Foamy macrophages were also seen, some of which contained pigment. Overall, the changes were most suggestive of dermatopathic lymphadenopathy (a benign, reactive lymph node hyperplasia often associated with various forms of dermatitis). A bone marrow biopsy was unremarkable. Eventually, the patient underwent exploratory laparotomy with biopsies of several enlarged mesenteric lymph nodes. These lymph nodes (see Images 01, 02, and 03) showed reactive hyperplasia with sinuses filled by numerous large, foamy macrophages. Special stains were negative for acid fast bacilli and fungi. The material within the foamy macrophages was positive for mucin using Periodic acid-Schiff with diastase (PASD) and the patient was diagnosed with Whipple's disease (a disease characterized by the accumulation of foamy macrophages in multiple sites throughout the body, especially the gastrointestinal tract; the foamy macrophages contain bacilli, Tropheryma whippelli, and characteristically stain with PASD).
Four years later, the patient was seen for continued proteinuria and a diagnostic renal biopsy was performed.
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