Bacterial meningitis: diagnosis by latex agglutination test and clinical features

To know the usefulness of Latex Agglutination Test (LAT) for the diagnosis of bacterial meningitis (BM), it was performed in all the 114 consecutive samples of CSF with polymorphs from 114 prospectively recruited children aged 2 months to 11 years. Definite diagnosis of BM based on culture and/or LAT was evident in 55. Among the 46 LAT positive, culture was positive in 3 only. Major organisms identified by LAT were H. influenzae B (HiB) in 28 and S. pneumoniae (SP) in 15. Ninety per cent of HiB and 67% of SP bacterial meningitis were under one year of age. Fever > 7 days prior to admission was not uncommon (38%) and 26% had received prior antibiotics. Meningeal signs were present in 64%. CSF cells were < 500/mm3 in 24% and sugar was > 50% of blood level in 23%. There was no significant difference in the immediate outcome between HiB and SP meningitis. The case fatality was 22% and was significantly high in cases who had altered level of consciousness on admission (p = 0.02). It is concluded that LAT is very useful for rapid diagnosis of BM.