1089 OEREBROSPINAL FLUID LACTIC ACID DEHYDROGENASE LEVELS IN MENINGITIS

Abstract

Cerebrospinal fluid (CSF) lactic acid dehydrogenase (LDH) has been utilized to help distinguish bacterial from non-bacterial meningitis. We reviewed the initial lumbar puncture (LP) results in 45 pediatric patients with documented bacterial meningitis seen between 1977-80. Patients ranged in age from 1 month to 16 years. No CSF specimens contained significant numbers of RBC's. Nine of the 45 patients had received oral antibiotics prior to admission. A CSF LDH value of more than 20 IU/L (40 units/ml) was considered presumptive evidence of bacterial meningitis, although antibiotics were begun in all patients immediately following the initial LP. A total of 9 patients (20%) had CSF LDH values < 20 IU/L: 1 of 4 patients with meningitis due to S. pneumoniae, 3 of 23 with H. influenzae, type b, meningitis, and 5 of 18 patients with N. meningitidis meningitis. There were no clinically distinguishing features of these 9 patients, and they were not among the patients who received oral antibiotics. During the same period of time, 29 patients found to have non-bacterial meningitis had CSF LDH determinations performed on their initial LP's. Of those 29, 13 (45%) had CSF LDH values >20 IU/L. For this group of 74 patients with meningitis encountered during a 3 year period, initial CSF LDH did not prove helpful in distinguishing bacterial from non-bacterial disease.