[Influence of age on the clinical manifestations of invasive pneumococcal disease and antibiotic resistance rates]

Abstract

Background and objective: Invasive pneumococcal disease (IPD) shows different epidemiological characteristics depending on age and pneumococcus serotype. The aims of the work were to analyze the clinical manifestations and mortality associated with IPD, the serotype isolated and the antibiotic resistance rates in different age groups.

Patients and method: Retrospectively, 141 patients with IPD diagnosed between 2002 and 2008 were studied. Patients were classified in 4 age groups: ≤ 2 year-old, 3-14 year-old, 15-64 year-old and ≥ 65 year-old.

Results: Pneumonia was the most common manifestation in all age groups (71%). Pneumococcal meningitis was more prevalent in patients ≤ 2 year-old (28 vs. 9%, P=.054) and empyema was more frequent in those between 3-14 year-old (31 vs. 5%, P<.001). Mortality was associated with age ≥ 65 year-old (odds ratio [OR] 7, 95% confidence interval [95% CI] 1.9-28.9), primary bacteremia (OR 7, 95% CI 1.9-28.9) and orotracheal intubation (OR 9, 95% CI 1.9-41.1). The more prevalent serotypes among patients ≤ 2 year-old were 14, 19A and 19F. The serotype 1 was most common in patients between 3-14 year-old and serotype 3 in those ≥ 65 year-old. A higher rate of non-susceptible penicillin strains was observed in pediatric population (42 vs. 19%, P=.007).

Conclusions: Age was related to the clinical manifestations, mortality and antibiotic resistance rates. Primary bacteremia was one of the risk factors of mortality.

Keywords: Age; Antimicrobial resistance; Clinical manifestations; Edad; Enfermedad invasiva por Streptococcus pneumoniae; Invasive pneumococcal disease; Manifestaciones clínicas; Mortalidad; Mortality; Resistencia a antimicrobianos.