[Pneumococcal meningitis in a tertiary care hospital: clinical characteristics, serotype distribution, and vaccination status].

Abstract

Introduction: Pneumococcal meningitis is a severe form of invasive pneumococcal disease (IPD). Despite the changes introduced by conjugate vaccines, pneumococcal meningitis remains a major clinical and public health challenge. Analyzing its current patterns allows the identification of serotypes that retain a higher invasive potential, the assessment of their relationship with clinical outcomes, and the guidance of future preventive strategies.

Methods: Retrospective descriptive study of patients with pneumococcal meningitis admitted between 2018 and 2024. Clinical, demographic, and microbiological variables were analyzed, including identified serotypes, markers of severity (ICU, intubation, death), vaccination status, and antimicrobial sensitivity.

Results: Thirty-six cases of pneumococcal meningitis were identified (8 pediatric, 28 adults), with a case fatality rate of 19.4% and an ICU admission rate of 69.4%. The serotype was identified in 88.9% of cases, with 17 different serotypes detected. The most aggressive serotypes were 8, 3, 16, 33, and 23B, and the most lethal were 8, 3, 23A, 25A, and 9N. Seventy-five percent of adults had an indication for vaccination, but only half had received any doses. Resistance to cefotaxime was documented in three strains (9N, 19A, 23F), one of which was associated with a fatal outcome.

Conclusion: Pneumococcal meningitis remains a serious condition. Serotypes such as 8 and 3 are associated with high mortality rates. Low vaccination coverage in at-risk groups represents a critical gap in prevention. Knowing the serotypes involved and their resistance profiles is key to adapting vaccination strategies and reducing the burden of this disease.