Value of cerebrospinal fluid analysis in the differential diagnosis of meningitis: A study in 710 patients with suspected central nervous system infection

Abstract

A prospective study to determine the value of cerebrospinal fluid analysis in the differential diagnosis of meningitis was performed in 710 consecutively observed patients, both children and adults, who underwent lumbar puncture due to suspected central nervous system infection. Diagnoses included acute or presumed bacterial meningitis (n = 79), acute or presumed viral meningoencephalitis (n = 218), acute unclassified meningitis (n = 6), other infections of the central nervous system (n = 37), non-infectious neurological diseases (n = 76) and control patients (n = 294). The sensitivity, specificity and predictive values were determined for cerebrospinal fluid white blood cell count, total protein, lactate, glucose and C-reactive protein levels as well as the blood/cerebrospinal fluid glucose ratio. Determination of cerebrospinal fluid levels of lactate (greater than or equal to 3.5 mmol/l) was found to be superior to the other tests. The C-reactive protein level gave no additional diagnostic information when the lactate level was determined. The white blood cell count, and total protein and glucose levels were often unreliable tools for differential diagnosis, largely due to low sensitivity at realistic discriminatory limits. The study confirms that no cerebrospinal fluid test is fully reliable in distinguishing bacterial meningitis from other forms of meningitis.

Quantitation of cerebrospinal fluid lactic acid in infectious and non-infectious neurological diseases

“…However, high specificity is desired to exclude expensive treatment of false positive cases (8). Previous studies have shown CSF lactate to have the highest sensitivity (89%-100%) and specificity (96%-100%) for discriminating acute untreated bacterial meningitis from viral meningitis, when the threshold limit was set at 3.5 mmol/L (36,37). This limit proved to also be relevant for tuberculosis (38), Listeria monocytogenes (39) and fungal meningitis (40).…”

“…CSF glucose is considered by clinicians to be a good marker to discriminate acute bacterial meningitis from viral meningitis. However, some authors reported low-sensitivity (around 50%) and high specificity with CSF glucose (36,37,41). Because CSF glucose concentrations are dependent on blood glucose concentrations, blood must be collected at the same time as CSF.…”

“…In contrast, CSF lactate concentrations are independent of blood concentrations (1). Thus, hyperglycemia and hypoglycemia may impair the CSF/blood glucose ratio, which exhibited 70%-91% sensitivity and 84%-99% specificity at a limit of -0.4 (36,37).…”

How appropriate are cerebrospinal fluid polymerase chain reaction requests for suspected central nervous system infections?

“…6 To optimise effective use of CSF PCR assays, previous studies have suggested algorithms based on CSF leucocyte count and total protein levels to determine when CSF PCR assays are indicated, 7,9 both of which are predictive of CNS infections. 3,8,9 In order to evaluate the appropriateness of CSF PCR requests at the James Cook University Hospital on the basis of criteria recommended in one of these studies, 7 a retrospective audit of all CSF PCR tests requested over a two-year period was conducted.…”

Cerebrospinal Fluid Glucose and Protein in Disposition and Treatment Decisions

“…[1][2][3][4][5][6][7] However, neither finding is diagnostic, and retrospective data suggest that CSF glucose and protein levels add little to initial treatment or disposition determinations. [8][9][10][11][12][13][14][15] Previous studies primarily included adults and were retrospective. We concurrently evaluated whether pediatric emergency physicians (EPs) consider either CSF glucose or protein values in making decisions to initiate antibiotic treatment and/or admit to the hospital patients undergoing lumbar puncture.…”