Frequency of Bacteria Isolated from Respiratory, Blood, and Wound Samples of Patients Hospitalized in Ayatollah Rouhani Hospital of Babol and Their Antibiotic Resistance Pattern

Due to the significant increase antibiotic-resistant bacteria, this study aimed to determine the frequency of bacteria causing respiratory, blood, and wound infections in patients admitted to the Rouhani Medical Center in Babol and to determine their antibiotic resistance pattern.

This study was carried out on 267 isolates collected from 158 blood samples, 60 respiratory samples, and 49 wound samples prepared from patients referred to Rouhani Hospital in 2022. The bacteria detected by the hospital laboratory were transferred to Mazandaran University of Medical Sciences and confirmed in the microbiology laboratory of the Faculty of Medicine. Then, the antibiotic susceptibility pattern of the isolates was analyzed by the disk agar diffusion method and interpreted according to the guidelines of the Institute of Clinical and Laboratory Standards. The results were analyzed using SPSS-19 statistical software.

The highest prevalence of bacteria isolated in this study (20.59%) was related to Escherichia coli and the lowest prevalence (1.12%) was related to Proteus mirabilis. Among 158 strains isolated from blood samples, E. coli (26.58%) was the most common bacteria. Among the 60 isolates collected from respiratory samples, Acinetobacter baumannii (23.33%) was the most prevalent and among the 49 strains isolated from wound samples, Staphylococcus aureus (30.61%) was the most common bacteria identified in this study. The antibiotic resistance pattern of the gram-positive bacteria identified in this study showed that the highest resistance (78.43%) of S. aureus strains was against tetracycline, while 3.92% of the isolates were resistant to linezolid. The resistance of coagulase-negative staphylococci and Enterococcus faecalis to the tested antibiotics varied between 12.5% and 83.33%. The amount of antibiotic resistance of Gram-negative isolates identified in this study also varied between 12.5% and 75.47%. The antibiotic resistance of S. aureus isolated from blood, respiratory, and wound samples to the tested antibiotics was 3.57% to 85.71%, 25% to 62.5%, and 25% to 62.5%, respectively, while tetracycline and linezolid were the least and most effective drugs against this bacterium. Among the gram-negative bacteria isolated from blood, respiratory, and wound samples, 34.51% to 61.94%, 41.66% to 64.58%, and 41.66% to 64.58% of the isolates were resistant to tested antibiotics, respectively, while piperacillin and imipenem were the least and most effective drugs.

The emergence of resistant strains in hospitals is related to continuous contact with all kinds of antibiotics, and the implementation of exact care strategies can lead to the prevention of drug resistance and spread. The most important factors to achieve these goals are the exact control of hospital care, prevention of hospital infections, and compliance with the principles of antibiotic use. Therefore, the essential role of infection control methods in hospitals, avoiding the unnecessary prescription of antibiotics, especially in surgical prophylaxis, proper isolation of patients, and appropriate use of laboratory facilities for the rapid diagnosis of microorganisms in each hospital is emphasized. The diagnosis and report of the antibiotic resistance pattern of common organisms in the region can be considered in empirical treatments to prevent the emergence of antibiotic resistance and high treatment costs for patients and medical centers.