P1.218: A study on the accuracy assessment of lumbar puncture in children with suspected purulent meningitis

Background: This study aimed to retrospectively analyze clinical data from neonates who underwent lumbar puncture for cerebrospinal fluid (CSF) examination in our hospital. By categorizing patients based on CSF results, we sought to identify clinical characteristics of neonates with abnormal CSF and explore risk factors for purulent meningitis, aiming to reduce unnecessary lumbar punctures.

Methods: A retrospective case-control study was conducted, including neonates who underwent CSF examination from July 2015 to June 2021. Patients were divided into abnormal CSF and normal CSF groups. Within the abnormal CSF group, further classification was made into purulent meningitis and non-meningitis subgroups. Clinical data were compared, and logistic regression analysis was used to identify independent risk factors for purulent meningitis. A predictive model was established and evaluated using receiver operating characteristic (ROC) curve analysis.

Results: 1. Among 1,042 neonates who underwent lumbar puncture, 323 (31%) had abnormal CSF. The abnormal CSF group showed higher rates of small-for-gestational-age (SGA) infants (P < 0.05) and significant differences in clinical manifestations such as fever ≥39°C, pallor, feeding refusal, irritability, seizures, and abnormal muscle tone (P < 0.05). Laboratory findings, including leukocyte count < 5×10^9/L, CRP >28.5 mg/L, and positive blood cultures, were significantly associated with abnormal CSF (P < 0.05).
2. Among 323 neonates with abnormal CSF, 226 were diagnosed with purulent meningitis. Risk factors for purulent meningitis included reduced movement and parenteral nutrition, while serum albumin >35.5 g/L was a protective factor.
3. Five independent risk factors for abnormal CSF were identified: feeding refusal (OR=2.783), irritability (OR=6.185), bulging fontanelle (OR=4.335), lethargy (OR=2.561), and SGA (OR=5.215).

Conclusion: The abnormal CSF rate was 31%, with a purulent meningitis incidence of 21.69%; Independent risk factors for abnormal CSF included feeding refusal, irritability, bulging fontanelle, lethargy, SGA, leukocyte count < 5×10^9/L, and CRP >28.5 mg/L; In the abnormal CSF group, reduced movement and parenteral nutrition were risk factors for purulent meningitis. This study provides valuable insights for identifying high-risk neonates and optimizing lumbar puncture use in suspected purulent meningitis cases.