Pattern of cerebrospinal fluid lactic dehydrogenase during treatment of bacterial meningitis.

Bacterial and aseptic meningitis are characterized by distinctive lactic dehydrogenase isoenzyme patterns. No studies have quantified the dynamics of lactic dehydrogenase isoenzyme distribution during treated bacterial meningitis. We used a retrospective case-series design, and reviewed files of all neonates with bacterial meningitis who attended our pediatric tertiary medical center for 8 years period. We identified neonates in whom a repeated lumbar puncture was indicated. Findings of cerebrospinal fluid analysis, including levels of lactic dehydrogenase isoenzymes, were compared with an age-matched reference group. In two patients with meningitis, lumbar puncture with cerebrospinal fluid analysis was repeated because of inadequate response to treatment or initially obscure etiologic pathogens. Both patients had initially low levels of lactic dehydrogenase-1 and lactic dehydrogenase-2 and high levels of lactic dehydrogenase-4 and lactic dehydrogenase-5, similar to other patients with bacterial meningitis. The distribution pattern of lactic dehydrogenase isoenzyme normalized after adequate antibiotic treatment. In light of the encouraging results in these two patients, further studies are warranted regarding the value of lactic dehydrogenase isoenzyme measurements for follow-up purposes and for evaluations of response to treatment.

Cerebrospinal fluid lactate dehydrogenase isoenzymes in children with bacterial and aseptic meningitis.

Differentiation of bacterial from aseptic meningitis may be difficult. Our aim was to determine the pattern of distribution of lactate dehydrogenase (LDH) isoenzymes in the cerebrospinal fluid (CSF) of patients with bacterial and aseptic meningitis. One hundred and fifty-seven patients with suspected meningitis were enrolled in the study. They were divided into 3 groups according to the culture- or bacterial antigen assay-proven diagnosis and CSF findings: bacterial meningitis (n = 31), aseptic meningitis (n = 65), and non-meningitis (n = 61). Total LDH level and percentages of LDH isoenzymes in the CSF were measured in each patient. Each group showed a distinct LDH isoenzyme distribution pattern, with a statistically significant difference among the groups in the percentages of the various isoenzymes. Compared with the non-meningitis group, total LDH activity in the CSF was high in the aseptic meningitis group (49.82+/-35.59 U/L, P < 0.001) and exaggerated in the bacterial meningitis group (944.53+/-112.3 U/L, P < 0.001). Low LDH-2 levels were unique to bacterial meningitis (P < 0.01), whereas high LDH-3 levels were characteristic of aseptic meningitis (P < 0.05). Both groups had low levels of LDH-1 and high levels of LDH-4 and LDH-5. In conclusion, the LDH isoenzyme pattern may be of clinical diagnostic value in meningitis, particularly when culture results are pending.

Lactic dehydrogenase isoenzyme in cerebrospinal fluid of children with infantile spasms.

Increased levels of lactic dehydrogenase (LDH) in cerebrospinal fluid (CSF) have been reported in association with several intracranial pathologies. We studied LDH isoenzymes in the CSF of children with infantile spasms. CSF samples collected from 12 patients (aged 4-9 months) with infantile spasms were analyzed for total LDH isoenzymes activity, and were compared to samples from 15 normal children. Mean total LDH activity in the CSF was 34.62 +/- 6.52 U/l. Patients with infantile spasms had a lower LDH-1 percentage and higher LDH-3 percentage; the differences from the control group were statistically significant (p < 0.01). LDH-4 and LDH-5 had similar values in both groups. Infantile spasm is apparently associated with a distinct LDH isoenzyme pattern in the CSF. More studies are needed to confirm the rise in LDH-2, LDH-3 and to determine the optimum time of analysis.

Reference values for lactic dehydrogenase activity and isoenzyme distribution in cerebrospinal fluid in neonates with fever but no evidence of cerebral disease.

Levels of lactic dehydrogenase (LDH) in the cerebrospinal fluid (CSF) have been used to evaluate a variety of neurologic disorders. However, few studies have been performed on neonates. CSF samples were collected from 39 neonates, 19 aged 1-4 weeks and 20 aged 5-8 weeks with neonatal fever. Findings were compared to those in 15 infants mean age 10 +/- 6.4 months with suspected nervous system disease and normal CSF findings. Mean total LDH activity in the CSF was significantly higher in the first month of life than in the second month of life and compared with the control group (p <0.001). The LDH isoenzyme pattern was also different, with lower values of LDH-1 than LDH-2 and -3 in the study groups. Differences were significant among all three groups for LDH-1 (p <0.001) and between the whole study group and the controls for LDH-2 and -3 (p <0.001). We propose reference values for total LDH activity and LDH isoenzyme distribution in the CSF of normal neonates.