Is Multidrug Resistance in Acute Otitis Media with Streptococcus pneumoniae Associated with a More Severe Disease?

OBJECTIVES

Streptococcus pneumoniae is the leading bacterial etiologic agent in acute otitis media (AOM), and it produces a more severe inflammatory response than other otopathogens. Additionally, the presence of multidrug-resistant (MDR) S. pneumoniae is an important issue in the management of AOM. The present pilot study aimed to ascertain whether MDR S. pneumoniae is associated with a higher inflammatory response and/or a more severe disease.

METHODS

This was a prospective, single-center study on nonpneumococcal conjugate vaccine-immunized pediatric patients with severe AOM. Demographic and clinical characteristics were recorded. Middle ear fluid was obtained and cultured for each patient; antibiotic-resistance profiling was tested for S. pneumoniae isolates. The C-reactive protein (CRP) level and complete blood count were determined. Patients with positive middle ear fluid culture for S. pneumoniae were divided into 2 groups according to antibiotic resistance profile: MDR and non-MDR.

RESULTS

MDR S. pneumoniae was identified in 15 (35.7%) of the 42 eligible patients. Children in this group had significantly higher CRP levels (72.23 ± 62.92 vs. 14.96 ± 15.57 mg/L, p < 0.001), higher absolute neutrophil count (8.46 ± 3.97 vs. 5.22 ± 4.5 × 103/mm3, p = 0.004), higher percentage of neutrophils (52.85 ± 13.49% vs. 38.34 ± 16.16%, p = 0.004), and were more prone to develop acute mastoiditis (p = 0.01). Receiver operating characteristic analysis identified CRP as the best biomarker to discriminate between the 2 groups of patients (AUC = 0.891).

CONCLUSION

MDR S. pneumoniae was associated with a more severe inflammatory response and a higher incidence of mastoiditis.