Prompt PCR diagnosis and treatment of tuberculous meningitis in a young child

Abstract

We report a case of tuberculous meningitis in a 3.5-year-old child who presented with subtle symptoms. The symptoms were somnolence, low-grade fever, and vomiting. The physical exam revealed neck stiffness and depressed sensorioum. Encephalopathy was suspected. Lumbar puncture showed modest pleocytosis. Cerebrospinal fluid smear for acid fast bacilli and later for Mycobacterium tuberculosis were negative. Polymerase chain reaction (PCR) for M. tuberculosis was positive twice, and the patient was diagnosed early in the course of the disease, treated accordingly, and recovered completely. Our laboratory performance consists of 36 tuberculous positive cases; 34 were PCR positive and 246 tuberculosis negative cases; nine were PCR positive, which is consistent with sensitivity of 94.4%, specificity of 96.3%, positive predictive value of 79%, negative predictive value of 99%, and likelihood ratio of 25.5. Tuberculous meningitis was diagnosed by a positive PCR whereas the smear and the Mycobacterium culture came back were negative. PCR has proven to be quite useful in the diagnosis of tuberculous meningitis and was life saving on our child in the case of this patient.