Allergic complications of meningococcal disease. II. Immunological investigations.

Immunological investigation of four patients with meningococcal meningitis who developed arthritis or cutaneous lesions showed circulating meningococcal antigen at the time of presentation in each patient. It was cleared from the circulation over the next few days. Circulating antibody was detectable in three of the four patients about a week after the onset of the illness. A marked fall in the serum C(3) level occurred in two patients at about that time. Deposits of meningococcal antigen, immunoglobulin, and C(3) were detected in the synovial fluid white cells of the two patients studied and in one of three skin biopsies examined. These findings suggest that the arthritis and cutaneous lesions of meningococcal meningitis may be due to immune complex formation.