Value of clinical and laboratory features in diagnosis of adult tuberculous meningitis

Abstract

Objective To create a simple differential diagnostic rule for tuberculous meningitis and cryptococcal meningitis in adults on the basis of basic clinical and laboratory features. Methods We compared the clinical and laboratory features of 219 adults admitted to our hospital during the period of 2000-2008; these patients satisfied the diagnostic criteria for tuberculous meningitis (n=100) and cryptococcal meningitis (n=119). Multivariate logistic regression analysis was employed to find the risk factors those could independently predict the tuberculous meningitis,so that the diagnostic rule could be created. Results Six risk factors those could independently predict the tuberculous meningitis were found, including gender, mind disorder, vision and/or hearing damage, amount of cerebrospinal fluid protein, total cerebrospinal fluid white-cell count and combination with periphery tuberculosis. A diagnostic rule developed from these features enjoyed a 78.0% sensitivity, a 95.2% specificity, a 92.9% positive predictive value and a 84.4% negative predictive value. Conclusion Simple clinical and laboratory features can help in the differential diagnosis between adult tuberculous meningitis and cryptococcal meningitis, which can be applied in primary hospital with limited microbiological resources. Key words: Meningitis; Tubercle bacillus; Diagnosis