Bacteriology of mastoid subperiosteal abscess in children.

Objective: Subperiosteal abscess (SA) is the most frequent complication of acute mastoiditis (AM). Of pathogens cultured from the external auditory canal or middle ear during myringotomy, 15% may be different from microorganisms isolated from the SA. We suggest, therefore, that only cultures obtained from the abscess cavity can truly reflect the bacteriology of this complication of AM. The purpose of our study was to analyze the infectious agents which cause SA and mastoid cortex erosion in children.
Material and Methods: The medical records of 35 children who underwent mastoidectomy for SA between May 1984 and April 2002 were evaluated.
Results: Mastoid cortex erosion was found at surgery in 72.7% of abscesses Purulent discharge was obtained from the SA cavity in 28 cases. The commonest pathogens isolated in these cases, as well as in 18 cases of mastoid cortex erosion, were Staphylococcus aureus and Streptococcus pyogenes, followed by Streptococcus pneumoniae. Hemophilus influenzae, Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae. Sterile culture was found in 25% of cases.
Conclusions: Mastoid SA is a unilateral disease that can recur. Early administration of anti-Staphylococcus medications should be considered for patients with SA as a complication of AM.