Isolation, identification, and antibacterial susceptibility testing of Moraxella catarrhalis isolated from the respiratory system of patients in northern Iran

Abstract

Background and Objectives: Moraxella catarrhalis is considered as an emerging pathogen and a new nosocomial infection agent. This study was conducted to isolate and identify M. catarrhalis from clinical samples (respiratory tracts) and assess them for antimicrobial susceptibility patterns. Methods: In total, 280 samples were collected from patients with respiratory tract infection, and 120 samples were obtained from healthy individuals in the control group. The isolates were identified by phenotyping and genotyping methods, and their antibiotic susceptibility was evaluated using disk diffusion methods. The presence of β-lactamase and efflux pump activity were specified via phenotypic methods. Finally, Bro and acrA genes in the isolates were detected by PCR technique. Results: The frequency of this bacterium was 9.64% (27 out of 280) in patients with respiratory tract infection and 4.16% (5 out of 120) in the control group. Although the isolates were resistant to penicillin, they had various responses against other antibiotics. The results obtained from molecular method showed that 90.6% and 84.3% of the isolates possessed Bro and acrA genes, respectively. There was a significant relationship (P<0.05) between the presence of Bro and acrA genes and antibacterial resistance to ampicillin, amoxicillin, cefazolin, cefuroxime, and chloramphenicol. Conclusion: Our findings confirmed the existence of M. catarrhalis in patients with respiratory diseases and the high prevalence of antibiotic resistant genes in M. catarrhalis isolates. Therefore, timely diagnosis and successful treatment can play important roles in preventing their spread.

Antimicrobial Resistance Pattern of Moraxella catarrhalis and Haemophilus influenza in Iran; a Systematic review

“…A study assessed resistance trends for M. catarrhalis in Twain, showed that all isolates were susceptible to amoxicillin/clavulanate, chloramphenicol, ce xime, cipro oxacin, erythromycin, levo oxacin [19]. Based on our studies all or majority of isolated M. catarrhalis had susceptibility to amoxicillin/clavulanate and erythromycin [10,11,17], and in two of our study study the susebility to cipro oxacin was high [10,17] while in another study 70% of isolated M. catarrhalis had resistancy to cipro oxacin [11]. In another study were conducted in Pakistan, about 45% of the cultures showed resistance to macrolides and 59% showed resistance to quinolones [20], nerveless, in our study majority of isolated M.cattarhalis had susceptibility to macrolides and quinolones.…”

“…Penicillin resistance was 100% and 70% in two of our studies [10,11], and even though one of our studies did not refer to the percentage of penicillin resistance, it did show that the majority of microorganisms were penicillin-resistant. [12].…”

“…Since all the isolates had β-lactamase enzymes, the results showed that they were all penicillin-resistant. In addition, resistance to other antibiotics was different [10]. In accordance with these ndings, 95 percent of M. catarrhalis isolates produced beta-lactamase [12], and another study found that penicillin resistance in M. cattarhalis was 100% [13].…”

“…There was a relationship between the Bro gene and antibiotic resistance to ampicillin, amoxicillin, cefazolin, and cefuroxime [10]. The Bro gene was found in 90.6 percent of M. catarrhalis.…”

“…The Bro gene was found in 90.6 percent of M. catarrhalis. There was also a link between the acrA gene and resistance to ampicillin, amoxicillin, cefazolin, cefuroxime, and chloramphenicol [10]. According to previous researches, the M. catarrhalis Bro gene was present in 87%, 73.3%, and 99.4% of the strains and was fully resistant to penicillin, ampicillin, and cefalotin [14][15][16].…”