antimicrobial resistance patterns of aerobic organisms in patients with chronic rhinosinusitis in hamadan, iran

background although effective strategies have been presented for preventing the spread of antibiotic resistance in iran, recent reports have revealed increasing antibiotic resistance among children and adults. objectives in the present study, we tried to provide a clear view of the antibiotic resistance status of aerobic organism as the most prevalent organism in patients with rhinosinusitis in hamadan, iran. patients and methods a cross-sectional study was conducted on 216 consecutive patients referred to otolaryngology clinics of imam khomeini and besat university hospitals in hamadan with clinical and radiological manifestations of chronic rhinosinusitis. two specimens were taken from each patient; one from the affected maxillary sinus by aspiration and another from the middle meatus and nasopharynx by swabbing. antibiotic susceptibility was tested by kirby bauer’s method; distributions of the isolates from middle meatus, nasopharynx and sinus were determined and the results of susceptibility test were analyzed. results among the aerobic organism from meatus and oropharynx, the most frequent isolated strains were alpha-hemolytic streptococcus (15.4%), followed by coagulase-negative staphylococcus (14.6%), and branhamella catarrhalis (13.2%), and the most prevalent isolated strains from sinus were s. aureus (19.1%), klebsiella pneumonia (16.4%), and b. catarrhalis (15.6%), respectively. the highest antibiotic susceptibility was detected to ciprofloxacin and ceftriaxone in most of the strains; susceptibility to ciprofloxacin ranged from 76.7% (for pseudomonas aeruginosa) to 100% (for escherichia coli and haemophilus influenza); susceptibility to ceftriaxone ranged from 71.4% (for acinetobacter baumannii) to 100% (for s. pneumonia, corynebacterium diphtheria, and h. influenza). besides, regardless of strain, the highest resistance was mostly detected to penicillin (ranging from 33.3% to 91.7%), and to ampicillin (ranging from 38.4% to 83.7%). conclusions our study showed that resistance to some antimicrobial agents including penicillin subgroups was considerably high for managing sinusitis. therefore, public health policies should be more focused on minimizing the misuse of these subgroups as well as limiting the inappropriate use of other agents with high susceptibility.