Recrudescence and relapse in bacterial meningitis of childhood.

Antibiotic therapy of bacterial meningitis in children may be complicated by reappearance of bacteria in cerebrospinal fluid during therapy (recrudescence) or within three weeks after therapy is stopped (relapse). Clinical and laboratory features of six children with recrudescence and of 21 children with relapse were reviewed. These complications occurred mainly in infants less than 2 years of age and comprised less than 1% of all cases of bacterial meningitis. Neither the initial nor the follow-up CSF findings were predictive of recrudescence or relapse. Prolonged or secondary fever was unrelated to these complications. Recrudescence was usually caused by inappropriate therapy whereas relapse after adequate therapy of bacterial meningitis was usually ascribed to persistence of infection in meningeal or parameningeal foci. Relapse did not become manifest until three or more days after discontinuation of therapy. It is concluded that routine examination of CSF at the end of adequate anti-microbial therapy is not necessary or useful when the patient has exhibited a satisfactory clinical response. Furthermore, the commonly recommended observation period of 48 hours in the hospital after discontinuation of therapy is not justified for a patient who has had an uneventful course.