Diagnostic accuracy of intracellular mycobacterium tuberculosis detection for tuberculous meningitis.

RATIONALE: Early diagnosis and treatment of tuberculous meningitis saves lives, but current laboratory diagnostic tests lack sensitivity. OBJECTIVES: We investigated whether the detection of intracellular bacteria by a modified Ziehl-Neelsen stain and early secretory antigen target (ESAT)-6 in cerebrospinal fluid leukocytes improves tuberculous meningitis diagnosis. METHODS: Cerebrospinal fluid specimens from patients with suspected tuberculous meningitis were stained by conventional Ziehl-Neelsen stain, a modified Ziehl-Neelsen stain involving cytospin slides with Triton processing, and an ESAT-6 immunocytochemical stain. Acid-fast bacteria and ESAT-6-expressing leukocytes were detected by microscopy. All tests were performed prospectively in a central laboratory by experienced technicians masked to the patients' final diagnosis. MEASUREMENTS AND MAIN RESULTS: Two hundred and eighty patients with suspected tuberculous meningitis were enrolled. Thirty-seven had Mycobacterium tuberculosis cultured from cerebrospinal fluid; 40 had a microbiologically confirmed alternative diagnosis; the rest had probable or possible tuberculous meningitis according to published criteria. Against a clinical diagnostic gold standard the sensitivity of conventional Ziehl-Neelsen stain was 3.3% (95% confidence interval, 1.6-6.7%), compared with 82.9% (95% confidence interval, 77.4-87.3%) for modified Ziehl-Neelsen stain and 75.1% (95% confidence interval, 68.8-80.6%) for ESAT-6 immunostain. Intracellular bacteria were seen in 87.8% of the slides positive by the modified Ziehl-Neelsen stain. The specificity of modified Ziehl-Neelsen and ESAT-6 stain was 85.0% (95% confidence interval, 69.4-93.8%) and 90.0% (95% confidence interval, 75.4-96.7%), respectively. CONCLUSIONS: Enhanced bacterial detection by simple modification of the Ziehl-Neelsen stain and an ESAT-6 intracellular stain improve the laboratory diagnosis of tuberculous meningitis.

[Association between metabolic syndrome and prognosis in acute ischemic non-embolic stroke].

OBJECTIVE: To investigate the association between metabolic syndrome (MS) and stroke severity in at-admission patients with acute ischemic non-embolic stroke and to study the impact of MS upon prognosis; and to assess the relative influence of each of five components of MS upon the risk of stroke severity. METHODS: The consecutive cases of ischemic stroke were prospectively registered in neurology wards from March 2006 to March 2008. Only those patients with an onset of stroke within 24 hours were included. The outcomes were followed up at the end of 3 months after stroke onset. MS was defined according to the Chinese Diabetes Society criteria. Logistic regression was used to estimate the correlation of MS and prognosis. RESULTS: A total of 342 patients with acute ischemic non-embolic stroke within 24 hours from onset were included. Eighty six patients (50 males, 36 females) had MS. The prevalence of individual components of MS was significantly higher in patients with MS as compared with those without. The delay from onset of symptoms to hospital admission and MS were associated with severe stroke in multiple logistic regression model (RR = 2.45, 95%CI, 1.14-5.27; RR = 1.85, 95%CI, 1.06-6.25 respectively). Analysis of the association between the development risk of sever stroke showed that hyperglycemia and low triglyceride level had associations with severe stroke (RR = 3.02, 95%CI, 1.75-8.59; RR = 0.85, 95%CI, 0.24-0.96 respectively). MS was not an independent predictor for case fatality and poor outcome 3 months after stroke onset (all P > 0.05). CONCLUSION: Not an independent predictor for mortality and poor outcome at 3 months after stroke onset, MS is an independent predictor for the severity of stroke and there is a higher development risk of severe stroke. Among MS components, hyperglycemia and low triglyceride level are correlated with the development risk of severe stroke. This finding has important clinical implication and confirms the importance of glycemic control during acute phase of ischemic stroke.