Pediatric Acute Mastoiditis in the Post-Pneumococcal Conjugate Vaccine Era

Objectives/Hypothesis: To determine whether the characteristics of acute mastoiditis in children have changed in the post-heptavalent pneumococcal conjugate vaccine (PCV7) era. Study Design: Case series. Methods: Clinical data for all patients admitted for acute mastoiditis at an urban tertiary children's hospital from July 1, 1996, to June 30, 2009, were reviewed. Patients with a known immune deficiency or cholesteatoma were excluded. Patients were divided into pre-PCV7 (July 1996 to December 2002; n = 38) and post-PCV7 (January 2003 to June 2009; n = 58) groups. Statistical analyses were used to compare the two groups. Results: Ninety-six children met the inclusion criteria. There was a 53% increase in admission for acute mastoiditis in the post-PCV7 era. The pre- and post-PCV7 groups had similar demographic features, presenting history, signs and symptoms, laboratory study results, and medical management. Computed tomography scan abnormalities seen in the two groups were similar except for subperiosteal abscess, which was seen more frequently in the post-PCV7 group. Streptococcus pneumoniae was the most common pathogen isolated in both groups. The patients in the post-PCV7 group had shorter hospital stays, despite undergoing more extensive surgery to address their disease. Conclusions: The number of acute mastoiditis admissions did not decrease with the widespread use of PCV7. Computed tomography findings and surgical procedures required to address acute mastoiditis indicate that the post-PCV7 group had more advanced disease. S pneumoniae remains the main pathogen in acute mastoiditis, and its nonsusceptibility to penicillin and ceftriaxone may be increasing.