Deadly carousel or difficult interpretation of new diagnostic tools for Whipple's disease: case report and review of the literature.

Whipple's disease is a rare systemic disorder classically presenting with weight loss, arthralgias, and diarrhea, which was first described in 1907. The causative bacterium Tropheryma whipplei, is a fastidious organism not growing on conventional media. Before the introduction of polymerase chain reaction (PCR)-based methods, the diagnostic gold standard was histological detection of diastase-resistant periodic acid Schiff (PAS)-positive macrophages or electron microscopy. As in the present case, contradictory results between the former and new diagnostic methods may obscure the correct diagnosis. We critically summarize the performance of the different diagnostic methods and discuss their impact on the clinical management of patients with suspected Whipple's disease.