Hearing loss in Malawian children after bacterial meningitis: incidence and risk factors

Abstract

We had an objective to describe the incidence and risk factors for hearing loss following acute bacterial meningitis in children admitted to the Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi. A double‐blind placebo‐controlled trial was designed from July 1997–March 2001 to determine whether early steroid therapy would reduce overall mortality and morbidity in childhood bacterial meningitis. The QECH, Blantyre, Malawi is a teaching and referral public hospital that serves the Blantyre area and receives referrals from throughout southern Malawi. Participants were children aged 2 months to 13 years, admitted with a diagnosis of bacterial meningitis, and the main outcome measures were mortality and morbidity following bacterial meningitis. Three hundred and ninety‐nine of 598 (66.7%) children survived; 33.6% were due to S. pneumoniae, 30% to Haemophilus influenzae type b, 15% to Neisseria meningitides, and 16% had no growth on CSF culture. Two hundred and sixty‐eight (67%) survivors had reliable hearing tests of whom 38% had impaired hearing, 77% of which was bilateral. Independent risk factors for hearing loss were the causative agent, presentation with a low coma score (52% vs. 34%, p = 0.006), a first CSF sample with a positive Gram stain for bacteria (65% vs. 44.3%, p = 0.003), a WBC < 100/cmm (p = 0.01), or a high protein level (50% if > 2000 mg/dl vs. 11% if <100 mg/dl). Associated neurological sequelae were highly associated with hearing impairment (p = 0.000012). We conclude that bacterial meningitis is the cause of many children's hearing impairment. Immunization against S. pneumoniae and H. influenzae would prevent many cases. Better first line antibiotics may reduce audiological damage. Deaf children in poorer parts of the world need more and vocal advocacy.

• meningitis
• children
• Malawi
• hearing loss
• risk factors