Invasive meningococcal disease

Vanessa L. Strelow, Jose E. Vidal

Invasive meningococcal disease (IMD) is a major public health and continues to cause substantial mortality and morbidity. Serotype C is the most frequent in Brazil. The clinical spectrum of IMD is broad (meningitis, meningococcemia or both) and the clinical evolution may be unpredictable. Main features associated with mortality are: age higher than 50 years old, seizures, shock, and meningococcemia without meningitis. Blood cultures should be obtained immediately. Lumbar puncture can be performed without previous computed tomography scan (CT) in most cases. Clinical features can be useful to predic patients where an abnormal CT scan is likely. Cerebrospinal fluid (CSF) culture and Gram stain should always be required. Latex agglutination sensitivity is highly variable. Polymerase chain reaction is specially useful when other methods are negative or delayed. Usually ceftriaxone should not be delayed while awaiting CSF study or CT. Dexamethasone can be used in meningococcal meningitis. Early suspicion of IMD and antibiotic in primary care before hospitalization, rapid transportation to a hospital, and stabilization in an intensive-care unit has substantially reduced the case-fatality rate. Vaccines against serotypes A, C, W-135, and Y are available while vaccines against serotype B are expected.