CSF lactate for accurate diagnosis of community-acquired bacterial meningitis

Abstract

CSF lactate measurement is recommended when nosocomial meningitis is suspected, but its value in community-acquired bacterial meningitis is controversial. We evaluated the diagnostic performance of lactate and other CSF parameters in a prospective cohort of adult patients with acute meningitis. Diagnostic accuracy of lactate and other CSF parameters in patients with microbiologically documented episodes was assessed by receiver operating characteristic (ROC) curves. The cut-offs with the best diagnostic performance were determined. Forty-five of 61 patients (74%) had a documented bacterial (n = 18; S. pneumoniae, 11; N. meningitidis, 5; other, 2) or viral (n = 27 enterovirus, 21; VZV, 3; other, 3) etiology. CSF parameters were significantly different in bacterial vs. viral meningitis, respectively (p < 0.001 for all comparisons): white cell count (median 1333 vs. 143/mm(3)), proteins (median 4115 vs. 829 mg/l), CSF/blood glucose ratio (median 0.1 vs. 0.52), lactate (median 13 vs. 2.3 mmol/l). ROC curve analysis showed that CSF lactate had the highest accuracy for discriminating bacterial from viral meningitis, with a cutoff set at 3.5 mmol/l providing 100% sensitivity, specificity, PPV, NPV, and efficiency. CSF lactate had the best accuracy for discriminating bacterial from viral meningitis and should be included in the initial diagnostic workup of this condition.

Cerebrospinal fluid abnormalities in meningeosis neoplastica: a retrospective 12-year analysis

“…In the present study, CSF lactate was correlated with the CSF cell count. In a recent receiver operating characteristic (ROC) curve analysis, CSF lactate had the highest accuracy for discriminating bacterial from viral meningitis with a cutoff set at 3.5 mmol/l [18]. Using a cutoff of 3.5 mmol/l, CSF lactate was also very useful to discriminate between cryptococcal or tuberculous meningitis and HIV chronic meningitis [19].…”

Clinical use of plasma lactate concentration. Part 2: Prognostic and diagnostic utility and the clinical management of hyperlactatemia

“…Similarly, in a meta‐analysis that included 25 studies and 1,692 people but excluded those with CNS disease that could increase CSF [LAC] (eg, stroke, seizures, cerebral hypoxia, brain trauma), CSF [LAC] had a pooled sensitivity of 96% (95% CI, 0.95–0.98), specificity of 94% (95% CI, 0.93–0.96), and AUROC of 0.984 in differentiating septic meningitis from aseptic meningitis . Consequently, empirical antimicrobial therapy is recommended in postoperative neurosurgical patients if CSF [LAC] is ≥4.0 mmol/L . CSF lactate cannot be used to rule out bacterial meningitis in patients previously treated with antimicrobials …”

“…Bacterial production of lactate is believed to account for only 10% of CSF [LAC] in cases of bacterial meningitis, with the majority originating from neurons, glial cells, and leukocytes. [119][120][121] In people, brain hypoxia and vascular compromise (ie, intracranial hemorrhage, mass lesions, trauma, stroke, seizures, hypoglycemic coma) also increase CSF [LAC]. 122,123 When confounding conditions have been excluded, CSF [LAC] can differentiate septic from aseptic meningitis.…”

“…123 Consequently, empirical antimicrobial therapy is recommended in postoperative neurosurgical patients if CSF [LAC] is ࣙ4.0 mmol/L. 121,127 CSF lactate cannot be used to rule out bacterial meningitis in patients previously treated with antimicrobials. 126 The reference interval for CSF [LAC] in horses has been stated as 1.92 ± 0.12 mmol/L (atlanto-occipital space) and 2.3 ± 0.21 mmol/L (lumbosacral space).…”

CSF in acute and chronic infectious diseases

“…The normal level of lactate in the CSF is 2 mmol/L and not different from that in the blood. Increase in lactate above 4 mmol/L is a more specific indicator for bacterial meningitis than other CSF markers in immediate evaluation (CSF cell count, CSF glucose, and protein concentration) (Donald and Malan, 1986;Giulieri et al, 2015; Julián-Jim enez and Morales-Casado, 2016; Slack et al, 2016;Xiao et al, 2016). (Pfaller et al, 2006).…”