Detection of Neisseria meningitidis in cerebrospinal fluid samples from suspicious cases of meningococcal meningitis using polymerase chain reaction and counterimmunoelectrophoresis.

Rapid diagnosis of meningococcal disease followed by an early treatment is essential. However, blood or cerebrospinal fluid cultures may not be successful because antibiotic treatment is often started before proper specimens are collected and because bacteria may die during transportation to the laboratory. Improvements in antibiotic therapy for specific microorganisms will require the use of more than one method for immunodiagnosis. In this study a collection of cerebrospinal fluid samples from Brazilian patients was analyzed. Gram stains, culture, counterimmunoelectrophoresis and clinical evaluations for meningococcal diseases were available. The sensitivity of nested PCR (nPCR) was 73% for cerebrospinal fluid of clinically suspected cases, whereas both sensitivity and specificity were 100% when subtypes of Brazilian epidemic strains (P1.7, P1.9 and P1.15) isolated from the samples were used.