Pneumococcal meningitis: a 12 year experience in a children's hospital prior to the universal immunization with a conjugate vaccine.

Introduction: Pneumococcal meningitis is causedby Streptococcuspneumoniae and hashigh morbidity and mortality rates. The objective of this study was to identify the epidemiological and clinical characteristics, antibiotic sensitivity and evolution of pneumococcal meningitis in children prior to the introduction of the vaccine in Argentina.

Methods: Patients younger than 18 years old hospitalizedat Hospital J. P. Garrahanbetween1999 and 2010 were included. Children's microbiology lab records and case records were reviewed.

Results: One hundred and eleven children with S. pneumoniae meningitis were identified. Forty cases were found in the 1999-2002 period, 35 in the 2003-2006 period, and 36 in the 20072010 period. The mean age was 7 months old (range: 1-191). One hundred and four patients were immunocompetent (94%). Only 20 patients (18%) had an underlying disease. The most commonly observed clinical presentation was neurological involvement in 80 patients (75%), and sepsis in59 (53%). Forty-nine patients (44%) had to be admitted to the ICU. A second clinical source of infection was identified in 24 patients (22%); half of these cases corresponded to pneumonia. Positive findings were observed in the cerebrospinal fluid culture of 103 patients (93%) and in the blood culture of 88 (79%). Resistance to penicillin was identified in 15% of cases, while 5% showed resistance to cefotaxime. Antibiotic resistance was reduced over the years. Complications occurred in 56 patients (50%), and 11 (10%) died because of the infection.

Conclusion: Antimicrobial resistance by S. pneumoniae was reduced over time. It is important to maintain epidemiological surveillance to assess the impact of immunization in Argentina.