[Wxanthema and acute polyarthritis in a young patient].

A young woman developed acute polysynovitis and vasculitis-like changes to the skin. Her blood cultures were positive for Neisseria meningitidis, enabling us to diagnose chronic meningococcemia. This finding was a surprise; in retrospect this diagnosis would not have been expected in light of the fact that there was no meningism, the patient's general condition was only slightly diminished and the temperatures were subfebrile. Besides an episode of vasculitis, the primary differential diagnosis of acute polysynovitis in young women should include a bacterial infection, for example with Neisseria. Usually, Neisseria gonorrhoeae (gonococci) are involved and, as in the case described, only very rarely Neisseria meningitidis (meningococci). The present case report is given to illustrate new clinical aspects of known, but rare disease, to remind clinicians to consider the differential diagnosis of acute polyarthritis and to generate discussion about the clinical signs and pathogenesis of reactive arthritides, in particular, Neisseria.