[Infective endocarditis as the only manifestation of Whipple's disease: an atypical presentation]

Diagnosis of Whipple's disease is difficult, and thus its frequency is probably underestimated, particularly in culture-negative infective endocarditis. However, it must be systematically searched for in such a situation, first because it is associated with a poor natural outcome, and second because Tropheryma whipplei is not covered by the conventional empirical therapy recommended for culture-negative infective endocarditis. Whipple's disease endocarditis is usually associated with weight loss, intestinal and joint involvement. Nevertheless, it is sometimes the only manifestation of the disease, which makes the diagnosis much more difficult. We report the case of a 66-year-old patient with Barlow's disease, who underwent mitral valve replacement for severe mitral regurgitation. Vegetations were observed on the resected valve, both macroscopically and histologically. No microorganism was found at first. The diagnosis of Whipple's disease endocarditis was finally obtained by Polymerase Chain Reaction on valve tissue, and later confirmed by Periodic Acid Schiff staining. The outcome was favorable after a prolonged antibiotic therapy including doxycycline and hydroxychloroquine.