High frequency of Streptococcus pneumoniae serotype 10A identified by PCR in cerebrospinal fluid culture-negative paediatric clinical samples.

INTRODUCTION

The aim of this study was to determine the distribution of Streptococcus pneumoniae (SP) serotypes in cerebrospinal fluid (CSF) samples, according to the microbiological detection strategy.

METHODS

Pneumococcal strains identification and serotyping were performed by conventional CSF culture and Quellung serotyping (CI-CS). In CSF culture-negative samples, identification and serotyping were conducted using direct PCR serotyping (PCR-DS).

RESULTS

Between 2018 and 2024, 144 strains/CSF samples (31 children and 113 adult cases) were studied. Serotypes 3, 8, 10A, 23B, 12B/12F and 6C accounted for the 54.9%. Serotype 10A represented 36.4% of those detected by PCR-DS in culture-negative CSF samples (4/11 cases [4/8 paediatric]) versus 6.0% detected by CI-CS (8/133 cases [3/23 paediatric]; p<0.01).

CONCLUSIONS

Direct PCR detection and serotyping in CSF clinical samples can complement the culture-Quellung serotyping and enhance the diagnosis of paediatric pneumococcal meningitis caused by serotype 10A.