Antibiotic Resistance Pattern in Intensive Care Units in a Large Referral Hospital in Iran.

Background & Objective: Antibiotic resistance, especially in the form of multidrug-resistant (MDR), is a big problem, especially in intensive care units (ICUs). This study aimed to evaluate antibiotic resistance and MDR patterns among patients hospitalized in the ICUs in one of the large referral centers in Iran. Methods: The present study was conducted at Imam Khomeini Hospital in Tehran (a great referral hospital), which admits critically ill patients requiring ICU services. To determine the rate of positive cultures for resistant strains, the patient's blood specimens were sent to the laboratory of the hospital for inoculation on proper culture media within 2 hours of extraction. Antimicrobial susceptibility tests were done using the Bauer-Kirby disk diffusion method. Results: A total of 1,755 samples were collected from the patients to assess microbial strains and antibiotic resistance. The most common microbial strains detected in the cultures extracted from peripheral blood samples were Klebsiella pneumonia (22.1%), Staphylococcus epidermidis (7.9%) and another coagulase-negative Staphylococcus (15.0%). The antibiogram test showed antibiotic resistance in 1,509 cases, leading to a resistance prevalence rate of 85.9%. The most common antimicrobial resistance observed was against cotrimoxazole (61.7%), ciprofloxacin (51.3%), imipenem (50.0%), and ampicillin (49.6%). The rate of MDR was found to be 96.3%. Conclusion: In Iran's ICUs, a significantly high level of antibiotic resistance may be seen especially the MDR pattern, which indicates the need to change the pattern of prescribing and managing these drugs in ICU centers.

Evaluation of Acinetobacter baumannii, Klebsiella pneumoniae, and Staphylococcus aureus respiratory tract superinfections among patients with COVID-19 at a tertiary-care hospital in Tehran, Iran.

BACKGROUND: The emergence of healthcare-associated infections (HAIs) or superinfections in COVID-19 patients has resulted in poor prognosis and increased mortality. METHODS: In a cross-sectional study, 101 respiratory samples were collected from ICU-admitted COVID-19 patients. The HAI rate, demographics, and antibiotic resistance were assessed. RESULTS: The HAI rate was 83.16% (76.62% bacterial and 6.54% fungal). The prevalence of 3 major HAI-causing organisms included Klebsiella pneumoniae (41.5%), Acinetobacter baumannii (20.8%), and Staphylococcus aureus (4.9%). Mortality and intubation ventilation proportions of 90% (p = 0.027) and 92.2% (p = 0.02) were significant among patients with superinfection, respectively. Multiple logistic regression analysis showed SpO2 pressure (odds ratio 0.842; 95% CI 0.750-0.945; p = 0.004) as a predictive factor in the association between antibiotic usage and mortality. More than 50% of patients received carbapenems. The resistance rates to at least one antibiotic of third-generation cephalosporins, aminoglycosides, quinolones/fluoroquinolones, tetracyclines, and ß-lactam inhibitors were 95.2%, 95.2%, 90%, 57.1%, and 100% among A. baumannii isolates and 71.4%, 55%, 69%, 61.9%, and 59.5% among K. pneumoniae isolates, respectively. A proportion of 60% was recorded for methicillin-resistant S. aureus isolates. CONCLUSION: As a result, antibiotic treatment should be administered following the microbial resistance profile. Contact isolation and infection control measures should be implemented as needed.

Co-infection of ST2IP carbapenem-resistant Acinetobacter baumannii with SARS-CoV-2 in the patients admitted to a Tehran tertiary referral hospital.

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAB) is among the most concerning cause of healthcare-associated infections (HAI) due to its high level of antibiotic resistance and high mortality. In the era of the COVID-19 pandemic, the key priority of infection control committees is to contain the dissemination of antibiotic resistant Gram-negative bacteria. Here, we aimed to timely recognize the emergence of CRAB in COVID-19 cases admitted to the wards of a tertiary referral hospital and to identify the genetic relatedness of the isolates. METHODS: From 30 March to 30 May 2020, a total of 242 clinical samples from COVID-19 cases were screened for CRAB isolates using standard microbiologic and antibiotic susceptibility tests. The PCRs targeting oxa23, oxa24, oxa58, blaTEM and blaNDM-1 genes were performed. Two multiplex PCRs for identifying the global clones (GC) of A. baumannii were also performed. The sequence type of CRABs was determined using Institut Pasteur (IP) multilocus sequence typing (MLST) scheme. RESULTS: Eighteen CRAB isolates were recovered from COVID-19 patients with the mean age of 63.94 ± 13.8 years. All but 4 COVID-19 patients co-infected with CRAB were suffering from an underlying disease. Death was recorded as the outcome in ICUs for 9 (50%) COVID-19 patients co-infected with CRAB. The CRAB isolates belong to GC2 and ST2IP and carried the oxa23 carbapenem resistance gene. CONCLUSION: This study demonstrated the co-infection of CRAB isolates and SARS-CoV-2 in the patients admitted to different ICUs at a referral hospital in Tehran. The CRAB isolates were found to belong to ST2IP, share the oxa23 gene and to have caused several outbreaks in the wards admitting COVID-19 patients.