In vitro and in vivo antimicrobial activity of topical ofloxacin and other ototopical agents

Background Ototopical agents are extensively used for otitis esterna (OE), acute otitis media identified by otorrhea in patients who have tympanostomy tubes (AOM-TT) and chronic suppurative otitis media (CSOM). The quinolones have particular value as ototopical agents because of the broad spectrum of antibacterial activity of importance in otic diseases and the high concentrations of antibacterial activity at the site of infection Methods. A survey of literature on in vitro activity and microbiologic efficacy in clinical trials of quinolone otic products for OE, AOM-TT and CSOM Results, OE: Floxin otic and Cortisporin TC otic suspension were equally effective in eradicating the three major pathogens Pseudomonas aeruginosa, Proteus mirabilis and Staphylococcus aureus, CSOM: Ofloxacin otic was effective in an open label trial in uniform eradication of S, aureus, P, aeruginosa, Proteus mirabilis and Enterobacter spp, AOM-TT: Ofloxacin otic and amoxicillin/clavulanate (by mouth) were equivalent clinically; rates of eradication of initial. pathogens were similar for Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis, but ofloxacin otic was superior in eradication of S, aureus and P, aeruginosa. Conclusions. In each of the studies of OE, CSOM and AOM-TT, ofloxacin otic solution was effective in eradicating the bacterial pathogen from the site of infection: equivalent to Cortisporin for children with OE; superior to amoxicillin/clavulanate for patients with AOM-TT who had acute drainage; and effective in eradicating bacterial pathogens from the external canal of patients with CSOM.