40 Current Status and Management of Community Acquired Meningitis

Abstract: Community acquired meningitis is associated with high mortality and morbidity. Bacterial meningitis is often a medical emergency, whereas viral meningitis often mild and remains unrecognized. In the past, the three most frequent bacterial pathogens of community acquired meningitis were H.influenzae, N.meningitides and S.pneumoniae. With the use of H.influenzae type b conjugate vaccine- incidence of H.influenzae meningitis in infants and children have dramatically reduced. S.pneumoniae is the most common cause of meningitis in adults. Listeria monocytogenes causes bacterial meningitis more in immunocompromised, pregnancy and older persons. During childhood and adolescence commonest organisms N.meningitidis followed by S.pneumoniae. Principle viruses identified causing meningitis are enteroviruses, herpesviruses, varicella zoster virus, flaviviruses, adenoviruses, etc..Patients commonly present with fever,confusion, lethargy, headache, vomiting and irritability. Neck stiffness present only in 50 % cases. Meningococcal disease often associated with petechial or purpuric skin rashes. Viral meningitis are often mildly symptomatic. Common neurological complications are cranial nerve dysfunction, seizure, focal cerebral signs and sensory neural deafness. Lumbar puncture is the most crucial investigation. Gram staining often revealed organisms and help in therapy. CT scan not mandatory,but needed if there is focal signs or features of raised intracranial tension. PCR more useful in diagnosing organisms in viral meningitis. Vancomycin and third generation cephalosporin is drug of choice if S.pneumoniae is suspected organism. For N.meningitidis and H.influenzae meningitis third generation cephalosporin is drug of choice. L.monocytogenes is susceptible to ampicillin. No specific antiviral therapy in case of viral meningitis except herpes simplex. Chemoprophylaxis is indicated for N.meningitidis and H.influenzae but not against S.pneumonia