Byline: Mohan. Sannathimmappa, Vinod. Nambiar, Rajeev. Aravindakshan
Background: Multidrug-resistant (MDR) Acinetobacter baumannii is of serious health concern and associated with high mortality. Data regarding the antibiotic resistance pattern of A. baumannii strains in Oman is limited. Objectives: To determine the antibiotic resistance pattern of A. baumannii from various clinical samples in a tertiary care hospital in the North-Batinah region of Oman. Methods: A. baumannii isolates recovered from various clinical samples in the Microbiology laboratory of Sohar Hospital, Oman, during 2015-2019 were retrospectively analyzed. Organism identification and their antibiotic resistance patterns were performed as recommended by the Clinical and Laboratory Standards Institute. Results: A total of 1890 A. baumannii nonduplicate isolates were found from clinical samples of 1326 patients. The isolates were more frequently isolated from elderly patients (40%) and in-patient department patients (67%). Infection/colonization was more common among patients treated in the medicine, intensive-care unit, and surgery departments. A. baumannii strains were highly resistant (50-83%) to most of the tested antibiotics, with the highest against ceftriaxone (83%) and ceftazidime (75%), and lowest against colistin (1%) and tigecycline (8%). Among the isolates, 67% (1265) were MDR strains. Of these, 22%, 32% and 16% were resistant to all six, five and four classes of the tested antibiotics. Conclusion: The study found that the frequency of isolation of MDR A. baumannii isolates in the northern region of Oman is high.
The emergence and continued spread of antimicrobial-resistant bacterial pathogens is a serious concern worldwide., Acinetobacter baumannii is a dangerous opportunistic nosocomial pathogen that has emerged in recent years as an important cause of a wide range of infections such as ventilator-associated pneumonia, surgical wound infection, meningitis, and urinary tract infection, especially in immunocompromised patients., Its ability to exist and survive in dry and humid surfaces, particularly in the hospital surfaces and equipment, makes controlling the nosocomial transmission extremely difficult., In addition, recent emergence of multidrug-resistant (MDR), extensively drug resistant (XDR), and pandrug-resistant clones of A. baumannii in hospital settings and the rapid dissemination of these strains among hospitalized patients has become a serious problem worldwide, as they are difficult to treat and are associated with high mortality.,,,,
In Oman, a recent surveillance report from the Royal Hospital, Muscat, showed an increasing trend in MDR A. baumannii infection. Another study conducted at Sultan Qaboos University, Muscat, showed a rise in infections associated with nonfermenters such as Pseudomonas and Acinetobacter . A molecular characterization analysis of MDR A. baumannii strains from all six GCC nations revealed that 69% of MDR strains carrying genes encode for OXA-23 and OXA-40 enzymes, which can confer it's resistance against the majority of antibiotics including carbapenems used for treating A. baumannii infections.
The prevalence and antibiotic susceptibility pattern of A. baumannii shows inter- and intra-national variations. Knowledge regarding local prevalence, predisposing factors, and the antibiotic susceptibility pattern of A. baumannii and other MDR pathogens is important for better management of infections. From Oman, there is a limited knowledge regarding the prevalence and antibiotic susceptibility pattern of A. baumannii ....