Identification of the organism and treatment will prevent progression to meningitis, endocarditis or other complications. The pericarditis may be purulent, occur in the first few days of meningococcal disease, and may demonstrate the organism. Alternatively, the pericarditis may be late, one to two weeks after infection, may be serosanguinous, and may contain no organisms. This later form responds to antiinflammatory drugs, including corticosteroids. Rare cases of purulent pericarditis due to N. meningitidis without other evidence of meningococcal disease are reported.
Arthritis occurs commonly during active meningococcal infection.
Often there is minimal effusion. The arthritis resolves as the infection is controlled with penicillin. There may be a late onset arthritis, after resolution of meningococcal infection. This, like the late-onset pericarditis, responds to antiinflammatory therapy. Septic purulent arthritis may occur spontaneously in the absence of meningococcal disease elsewhere, but this presentation is unusual.