An autopsy case of tuberculous meningitis undiagnosed by nested-PCR of CSF samples and brain biopsy

Abstract Nested polymerase chain reaction (PCR) testing of cerebrospinal fluid (CSF) has higher diagnostic sensitivity with regard to tuberculous meningitis (TBM) than conventional methods. Herein we describe the autopsy case of a 70-year-old woman with TBM that could not be diagnosed via nested PCR in CSF, even though it was performed three times. The clinical course, magnetic resonance imaging results, and elevated adenosine deaminase levels in CSF were consistent with TBM. We also performed a brain biopsy from the thickened leptomeninges of the patient, which showed granulomatous leptomeningitis consistent with TBM. However, we were not able to identify tuberculous bacilli by the acid-fast bacterial staining, single PCR test, and culture of the biopsy preparations. We finally diagnosed TBM in this case by the positive results of both the fourth PCR test and culture of her CSF, which were taken 7 days before her death. This case suggests that even the combination of repetitive nested PCR in CSF and brain biopsy lacks adequate sensitivity to exclude TBM in some patients.