Role of cerebrospinal fluid lactate in diagnosing meningitis in critically ill patients

Table 3 Comparison of various cerebrospinal fluid parameters for diagnosing meningitis

CSF Parameters	Cut-off	Sensitivity, %	Specificity, %	NPV, %	PPV, %	Accuracy, %	AUC	CI	P value
TLC (Cell/mm3)	> 55	73.9	100	100	88.9	91.5	0.92	0.84-1	< 0.001a
Lactate levels (mmol/L)	> 2.7	82.6	72.9	59.4	89.7	76.1	0.81	0.7-0.9	< 0.001a
Protein (mg/dL)	> 104.4	56.5	87.5	68.4	80.8	77.5	0.73	0.6-0.9	0.002a
Sugar (mg/dL)	> 63	56.5	83.3	61.9	80.0	74.6	0.7	0.6-0.9	0.006a

^aP value statistically significant.

CSF: Cerebrospinal fluid; AUC: Area under the curve; CI: Confidence interval; NPV: Negative predictive value; PPV: Positive predictive value; TLC: Total leucocyte count.