Clinical features of mild systemic meningococcal disease with characterization of bacterial isolates.

Neisseria meningitidis is an important cause of fulminant septicemia and meningitis in children. Only limited reports of mild disease associated with this organism exist. In this study, we describe eight children, ages 2.5-19 months, with mild meningococcal disease and characterize the meningococcal isolates from some of these patients. Children with mild meningococcal disease presented with a mean fever of 40.1 degrees C, but without purpura or petechiae. Five were diagnosed as having otitis media and were not thought to be seriously ill when initially observed. Six of the eight children had complete resolution of their clinical symptoms as outpatients. One had apparent meningococcal meningitis that sterilized without antibiotic therapy, and one had persistent low grade bacteremia that cleared within 48 hours after institution of parenteral antibiotics. Characterization of the meningococcal isolates from three of the patients revealed that the organisms were encapsulated, piliated, and contained similar outer membrane proteins. This report confirms that blood stream invasion by N. meningitidis organisms may result in clinically mild disease.