In children with chronic suppurative otitis media, should one prescribe topical or systemic antibiotics?

Abstract

C hronic suppurative otitis media (CSOM) is one of the most common chronic childhood infections worldwide. Considerable variation in prevalence is noted globally; the highest prevalence rates are reported in Aboriginal, and particularly, Inuit children populations, in which this disease is considered endemic. Literature on CSOM therapy primarily uses short-term clearance of ear drainage as the primary outcome. While the literature on CSOM has shortcomings in terms of length of follow-up, sample size, methodological quality and lack of paediatric studies, there is reasonable evidence for the efficacy of topical quinolones following aural toilet. Part a: EvidEncE-BasEd answEr and summaryThe WHO defines CSOM as "otorrhea through a perforated tympanic membrane present for at least two weeks" (1). CSOM can occur when acute otitis media (AOM) causes acute perforation of the tympanic membrane or when AOM occurs in conjunction with chronic perforation or tympanostomy tubes (2). The most common sequela of CSOM is conductive or sensorineural hearing loss (3). The Cochrane Database of Systematic Reviews and Google Scholar were searched in January 2012, identifying three rel- The WHO guidelines, covering the relative effectiveness of topical and systemic antibiotics, drew on a 1998 Cochrane review of all interventions for CSOM, which was comprised of only adult trials (7). The evidence on topical versus systemic antibiotics was taken from six studies and favoured topical antibiotics (OR 0.46 [95% CI 0.30 to 0.68]) for resolving otorrhea and eradicating middle ear bacteria; the effect estimate was strengthened when heterogeneity was decreased by excluding the two lowest quality trials from the analysis (OR 0.19 [95% CI 0.1 to 0.32]). The Cochrane review concluded that of the topical antibiotics studied, topical quinolones were more effective than topical nonquinolones (OR 0.36 [95% CI 0.22 to 0.59]), and that there was no additive benefit from combining systemic and topical antibiotics (7). The guideline authors also note that "there is general agreement that aural toilet must be part of the standard medical treatment for CSOM" (3), because it reduces the quantity of infected material, thereby facilitating penetration of topical treatments.The The benefits of exclusively analyzing paediatric data motivated Woodfield and Dugdale (6) to rerun the searches from the Cochrane reviews, selecting only the trials involving children. None of these directly compared topical with systemic antibiotics. Nonetheless, they concluded that topical quinolones alone were the most effective short-term treatment for CSOM in children.There are some theoretical reasons for the superiority of topical over systemic administration of antibiotics for CSOM. Due to poor vascularization of the middle ear mucosa, systemically delivered antibiotics do not penetrate well. For example, oral amoxicillin at 90 mg/kg results in a middle ear concentration of only 6 µg/mL to 10 µg/mL compared with 3000 µg/mL of antibiotic following application of a 0.3% antibioti...