title: Molecular characterization and antibiotic susceptibility of Haemophilus influenzae clinical isolates.
abstract: Haemophilus influenzae can cause invasive and severe infections in both adults and children such as otitis media, sinusitis, pneumonia, meningitis and bacteremia. The emerging antibiotic resistance in recent years against ampicillin and several other antibiotics among strains of H. influenzae gives cause for serious concern. Here, we investigate ß-lactamase (BL) activity in clinical isolates of H. influenzae, profile their resistance to antibiotics, and characterize the clonal relationship of the isolates. Antibiotic susceptibilities of 92 clinical isolates of H. influenzae (March 2011-May 2012) were determined using the disk diffusion method according to the Clinical & Laboratory Standards Institute (CLSI), and BL activity was detected using the nitrocefin disk method. The Rep-PCR method was used to characterize clonality of the isolates. All strains were found to be susceptible to levofloxacin and cefotaxime. Four isolates out of 92 (4.3%) were found resistant to ampicillin, one isolate (1.1%) was resistant to amoxicillin/clavulanic acid, 21 isolates (22.8%) were resistant to trimethoprim-sulfamethoxazole (SXT), and three isolates (3.3%) showed BL activity. One strain was BL-negative but resistant to ampicillin. The three isolates with BL activity and four isolates with resistance to ampicillin did not have a clonal relationship. Three distinct clones [clone A (with subclones A1 and A2), clone B, and clone C] were identified among the SXT-resistant strains. Most of the H. influenzae isolates in this study were susceptible to the antibiotics while SXT resistance was relatively more prevalent, which suggests that significant obstacles in the therapeutic use of antibiotics against H. influenzae strains are not expected in our region.
authors.affiliation: Department of Medical Microbiology, Erciyes University Medical Faculty, Kayseri, Turkey.
authors.forename: Hüseyin
authors.initials: H
authors.lastname: K L Ç
authors.affiliation: Department of Medical Microbiology, Istanbul University Cerrahpa?a Medical Faculty, Istanbul, Turkey.
authors.forename: Selcan
authors.initials: S
authors.lastname: Akyol
authors.affiliation: Department of Medical Microbiology, Erciyes University Medical Faculty, Kayseri, Turkey.
authors.forename: Õmür Mustafa
authors.initials: ÕM
authors.lastname: Parkan
authors.affiliation: Department of Medical Microbiology, Erciyes University Medical Faculty, Kayseri, Turkey.
authors.forename: Gõkçen
authors.initials: G
authors.lastname: Dinç
authors.affiliation: Department of Medical Microbiology, Kayseri Training and Research Hospital, Kayseri, Turkey.
authors.forename: Hafize
authors.initials: H
authors.lastname: Sav
authors.affiliation: Department of Medical Microbiology, Erciyes University Medical Faculty, Kayseri, Turkey.
authors.forename: Gonca
authors.initials: G
authors.lastname: Aydemir
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001769:Blood / Q000382:microbiology; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology; D002555:Cerebrospinal Fluid / Q000382:microbiology; D002648:Child; D052978:Disk Diffusion Antimicrobial Tests / Q000379:methods; D004352:Drug Resistance, Microbial / Q000187:drug effects / Q000235:genetics; D004423:Ear / Q000382:microbiology; D005838:Genotype; D060005:Genotyping Techniques / Q000379:methods; D006193:Haemophilus influenzae / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007223:Infant; D008826:Microbial Sensitivity Tests / Q000379:methods; D013183:Sputum / Q000382:microbiology; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases