Neuraminidase activity in bacterial meningitis
The Journal of Clinical Investigation
|May 1, 1971
Summary
Neuraminidase enzyme activity was studied in bacterial meningitis. Elevated free N-acetylneuraminic acid (NANA) in cerebrospinal fluid was linked to severe pneumococcal meningitis outcomes.
Area of Science:
- Microbiology
- Neurology
- Biochemistry
Background:
- Bacterial meningitis remains a significant cause of morbidity and mortality.
- The role of specific bacterial enzymes, such as neuraminidase, in disease pathogenesis is not fully understood.
- N-acetylneuraminic acid (NANA) is a key component of sialylated glycoconjugates and its metabolism can be altered during infection.
Purpose of the Study:
- To investigate the presence and activity of neuraminidase in different types of bacterial meningitis.
- To determine the correlation between neuraminidase activity and clinical outcomes, including morbidity and mortality.
- To assess the levels of free and total NANA in cerebrospinal fluid (CSF) of meningitis patients and their association with disease severity.
Main Methods:
- Neuraminidase and N-acetylneuraminic acid (NANA) aldolase activity were assayed in bacterial strains isolated from cerebrospinal fluid (CSF).
- CSF samples from patients with Haemophilus influenzae, meningococcal, and pneumococcal meningitis were analyzed for free and total NANA concentrations.
- Clinical data, including patient survival, presence of coma, and bacteremia, were correlated with CSF NANA levels.
Main Results:
- Neuraminidase was not detected in H. influenzae or meningococcal strains, but was elaborated by all tested pneumococcal strains.
- Elevated total NANA levels were observed in all types of bacterial meningitis.
- Abnormal concentrations of free CSF NANA were specifically found in pneumococcal meningitis patients, and were associated with coma, bacteremia, and poorer survival rates.
Conclusions:
- Neuraminidase is produced by Streptococcus pneumoniae but not by H. influenzae or Neisseria meningitidis.
- Elevated free CSF NANA concentrations are a potential biomarker for severe pneumococcal meningitis.
- Neuraminidase may play a role in the pathogenesis of pneumococcal meningitis, contributing to adverse clinical outcomes.
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