Clinical study of meningitis in children and role of adenosine deaminase in differentiating tubercular from non-tubercular meningitis

Abstract

Background: In diseases where cell mediated immunity plays an important role like in tuberculosis, CSF (Cerebrospinal fluid) adenosine deaminase (ADA) activity is increased. Hence, this testing is done especially among children with suspected tubercular meningitis. The objective of this was to study role of Adenosine Deaminase in differentiating tubercular from non-tubercular meningitis.Methods: This was a hospital based cross sectional study was carried out among 50 children of proven meningitis for a period of two years. CSF ADA levels were done for all cases. They were divided into tubercular meningitis and non-tubercular meningitis group and compared.Results: Incidence of tuberculous meningitis (TBM) was found high in the age group 5-8 years. Male:female ratio was 2.3:1. Fever was present in all cases followed by vomiting and neck rigidity. CSF AFB was positive in 3 cases (6%). Neuroimaging was done in all cases in which 3 patients had basal exudate in which 2 patients had TBM and 1 patient was Non-TBM. 3 patients had hydrocephalus in MRI in which 2 had TBM diagnosed and 1 had non-TBM. As per ADA levels, 10 were diagnosed as TBM out of which 8 patients had ADA level ≥10 IU/L and 2 had ADA level <10 IU/L which was missed by ADA and later confirmed by other modalities.Conclusions: It was concluded that if ADA level in CSF is ≥10IU/l the diagnosis of TBM should be considered.