Background: As human immunodeficiency virus (HIV) infection primarily impairs cellular immunity, the immune responses of HIV-infected individuals to tuberculous bacilli may be inadequate. The features of pulmonary and abdominal tuberculosis evident in HIV-positive (HIV-P) patients with severe immunosuppression are markedly different from those seen in HIV-negative (HIV-N) patients. However, such differences have not been reported in tuberculous meningitis (TBM). Here, we therefore compared the clinical, radiological and pathological features of TBM in patients with and without HIV infection.
Methods and results: Twenty-two HIV-P patients with TBM, seen over 5 years, were studied and compared with 31 HIV-N patients with TBM. Although clinical features were similar, cognitive dysfunction was more common amongst the HIV-P group. Pathological features were markedly different in the HIV-P group reflecting severely reduced and atypical inflammatory response, and extensive vasculopathy. This manifested as absence or minimal meningeal enhancement and absence of communicating hydrocephalus on CT scan in HIV-P patients. Mortality was higher within the HIV-P group and depressed levels of consciousness and hemiplegia were associated with poor prognosis.
Conclusion: The clinical, radiological and pathological features of TBM in HIV-P patients are distinctly different from those without HIV infection; a finding previously unreported.