Background.
Tuberculous and cryptococcal meningitis (TBM and CM) are the most common causes of opportunistic meningitis in HIV-infected patients from resource-limited settings, and the differential diagnosis is challenging.
Objective.
To compare clinical and basic cerebrospinal fluid (CSF) characteristics between TBM and CM in HIV-infected patients.
Methods.
A retrospective analysis was conducted of clinical, radiological and laboratory records of 108 and 98 HIV-infected patients with culture-proven diagnosis of TBM and CM, respectively. The patients were admitted at a tertiary center in Sao Paulo, Brazil. Logistic regression model was used to distinguish TBM from CM and derive a diagnostic index based on the adjusted odds ratio (OR) to differentiate these two diseases.
Results:
In multivariate analysis, TBM was independently associated with: CSF with neutrophil predominance (OR=35.81, 95% CI 3.80–341.30, P=0.002), CSF pleocytosis (OR=9.43, 95% CI 1.30–68.70, P=0.027), CSF protein >1.0g/l (OR=5.13, 95% CI 1.38–19.04, P=0.032), and Glasgow Coma Scale <15 (OR=3.10, 95% CI 1.03–9.34, P=0.044). Nausea and vomiting (OR=0.27, 95% CI 0.08–0.90, P=0.033) were associated to CM. Algorithm-related area under receiver operating characteristics curve was 0.815 (95% CI: 0.758–0.873, P<0.0001), but an accurate cut-off was not derived.
Conclusion:
Although some clinical and basic CSF characteristics seem to be useful in the differential diagnosis of TBM and CM in HIV-infected patients, an accurate algorithm was not identified. Optimised access to rapid, sensitive and specific laboratory tests is essential.