High Prevalence of Iron Acquisition Genes Among Acinetobacter baumannii Strains Isolated From Patients With Urinary Tract Infections in Southeast of Iran

Background: Acinetobacter baumannii is the most clinically prominent species of the Acinetobacter genus and is commonly found in hospital environments. In mammals, the iron element is virtually unavailable to invading bacteria, being mainly incorporated into iron transport and storage proteins. Therefore, iron acquisition systems are important factors for the pathogenicity of A. baumannii strains. Objectives: The aim of this study was to determine the frequency of iron acquisition genes among A. baumannii isolates, collected from patients with urinary tract infections, for the first time in Iran. Patients and Methods: A total of ۱۰۰ A. baumannii isolates were collected from patients with urinary tract infections in Zabol, southeast of Iran. All isolates were evaluated to determine the prevalence of iron acquisition genes, including tonB (TonB-dependent receptor), barA (acinetobactin ABC transporter), feoB (ferrous iron transport protein B), entA (acinetobactin siderophore precursor), A۱S_۲۵۶۳ (siderophoreinteracting protein), and hemO (heme oxygenase) using the multiplex polymerase chain reaction (PCR) method. Results: A high prevalence of genes encoding iron acquisition systems were observed in A. baumannii isolates. The frequency of tonB, barA, feoB, entA, A۱S_۲۵۶۳, and hemO genes were ۸۵, ۹۷, ۹۹, ۹۸, ۹۹, and ۹۵%, respectively. Based on the distribution of the various iron acquisition genes, all the studied isolates exhibited seven gene profile patterns. Conclusions: This is the first report on the prevalence of iron acquisition genes among A. baumannii isolates collected from patients with urinary tract infections. The high prevalence of iron acquisition genes in A. baumannii isolates suggests that these virulence factors play an important role in the development of urinary tract infections.