Antibiotic Treatment of Otitis Media May Not Prevent Mastoiditis

Antibiotic treatment of otitis media may not be indicated to prevent mastoiditis, according to the results of a retrospective cohort study reported in the February issue of Pediatrics.

"Information is needed on whether mastoiditis has increased in association with the decline in antibiotics prescribed to children by primary care physicians in the United Kingdom," write Paula Louise Thompson, BSc, MSc Epid, from the University of London, United Kingdom, and colleagues. "Ecological studies of routine health care databases have suggested that the reduction in antibiotic prescribing to children may be associated with an increase in rare complications of bacterial infection, particularly mastoiditis after otitis media. Individual patient level analyses are now required."

The goals of this study were to examine time trends in mastoiditis incidence, the frequency of preceding otitis media, and the effect of antibiotics for otitis media on the subsequent risk for mastoiditis in children.

The study cohort consisted of 2,622,348 children within the UK General Practice Research Database (GPRD) who were aged 3 months to 15 years between 1990 and 2006. The investigators assessed the risk for mastoiditis within 3 months after otitis media diagnosis and the protective effect of antibiotics.

Most children with mastoiditis had not seen their general practitioner for otitis media; among 854 children with mastoiditis, only 35.7% had antecedent otitis media.

Between 1990 and 2006, the incidence of mastoiditis remained stable at approximately 1.2 per 10,000 child-years. After otitis media, the risk for mastoiditis increased with age and was halved by antibiotics. The risk for mastoiditis after otitis media treated with antibiotics was 1.8 per 10,000 episodes (139/792,623) vs 3.8 per 10,000 episodes (149/389,649) without antibiotics.

To prevent 1 child from the development of mastoiditis, general practitioners would have to treat 4831 otitis media episodes with antibiotics. If otitis media were no longer treated with antibiotics in the United Kingdom, there would be an extra 255 cases of childhood mastoiditis but 738,775 fewer antibiotic prescriptions per year.

"Antibiotics halve the risk of mastoiditis, but the high number of episodes needing treatment to prevent 1 case precludes the treatment of otitis media as a strategy for preventing mastoiditis," the study authors write. "Although mastoiditis is a serious disease, most children make an uncomplicated recovery after mastoidectomy or intravenous antibiotics. Treating these additional otitis media episodes could pose a larger public health problem in terms of antibiotic resistance."

Limitations of this study include possible misclassification of the occurrence and timing of exposures, underestimation of the incidence of mastoiditis, possible miscoding of mastoiditis, possible underestimation of treatment efficacy if general practitioners were more likely to record otitis media if they prescribed antibiotics, prescriptions not directly linked to indication, and lack of compliance data or severity data.

"GPs [general practitioners] and pediatricians working in primary care need to be able to recognize the signs of mastoiditis (postauricular swelling and protrusion of the auricle), particularly in older children, and to refer promptly to ENT [ear, nose, and throat] services," the study authors conclude. "Trends in antibiotic prescribing need to be formally monitored in association with the longitudinal follow-up of individual patient disease outcomes data, to ensure that any changes in antibiotic use are not causing harm."

from: www.medscape.com