Whipple's disease: misdiagnosed as sarcoidosis with further tricuspid valve endocarditis and pulmonary embolism - a case report

Abstract

GH Whipple described a 36-year-old physician in 1907 with gradual loss of weight and strength, stools consisting chiefly of neutral fat and fatty acids, indefinite abdominal signs and a peculiar multiple arthritis. The patient died of this progressive illness. Whipple called it intestinal lipodystrophy since he observed accumulation of large masses of neutral fats and fatty acids in the lymph spaces. It was renamed Whipple's disease in 1949. An infectious aetiology was suspected as early as Whipple's initial report. However, successful treatment with antibiotics was not reported until 1952, which resulted in dramatic clinical responses. The cause is now known to be Tropheryma whipplei. Light and electron microscopy of infected tissue identified a gram-positive, non-acid-fast, periodic acid-Schiff (PAS) positive bacillus with a characteristic trilamellar plasma membrane resembling that of gram-negative bacteria. Whipple's disease is extremely rare. It is a systemic infectious disorder affecting mostly middle-aged white men. The clinical presentation is often non-specific, which may make its diagnosis difficult. The four cardinal clinical manifestations are arthralgias, weight loss, diarrhoea and abdominal pain. The frequently vague articular symptoms can precede the diagnosis of Whipple's disease by an average of 6-8 years. Lymph nodes and other tissues may present diagnostic problems, since the changes in routinely stained sections may mimic those of sarcoidosis. The detection of PAS-positive histiocytes in the small intestine remains the mainstay of the diagnosis, although Whipple's disease without gastrointestinal involvement is described. We illustrate a case in which, retrospectively, the clinical presentation would have been typical for Whipple's disease. However, the clinical presentation and the histological examinations of lymph nodes, liver biopsies and ascites initially were misinterpreted as sarcoidosis with consecutive immunosuppressive therapy and progressive worsening of the patient's health presenting at least as sepsis with endocarditis.

Figure 1

Four chamber view with large vegetation on the tricuspid valve during diastole. LV, left ventricle; RA, right atrium; RV, right ventricle.

Figure 2

Four chamber view with large vegetation on the tricuspid valve during systole. LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle.

Figure 3

Skin biopsy – subcutis with PAS-positive histiocytes (magnification: ×600).

Figure 4

PAS staining of a duodenal-biopsy specimen with numerous macrophages containing PAS-positive granules (magnification: ×600)