Antibiotic resistance and genotyping of gram-negative bacteria causing hospital-acquired infection in patients referred to Children’s Medical Center

Abstract

Setareh Mamishi,1,2 Shima Mahmoudi,2 Naimeh Naserzadeh,1 Reihaneh Hosseinpour Sadeghi,2 Mohammad Taghi Haghi Ashtiani,3 Abbas Bahador,4 Mohammad Reza Abdosalehi,1 Maryam Rahmani,5 Babak Pourakbari2 1Department of Infectious Diseases, Pediatrics Center of Excellence, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran; 2Pediatric Infectious Disease Research Center, Tehran University of Medical Science, Tehran, Iran; 3Department of Pathology, Pediatrics Center of Excellence, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran; 4Department of Microbiology, Tehran University of Medical Sciences, Tehran, Iran; 5Pediatrics Center of Excellence, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, IranCorrespondence: Babak PourakbariPediatric Infectious Disease Research Center, Children Medical Center Hospital, Tehran University of Medical Sciences, 62 Gharib Street, Keshavarz Blvd, Tehran, IranTel [phone]Fax [phone]Email [email protected] and aim: Hospital-acquired infection (HAI) is a major problem worldwide. Understanding patterns of bacterial etiology and antibiotic susceptibility is vital to combating HAI. Besides, typing of isolates is important to establish the intra-hospital surveillance of resistant clones. In this study, we aimed to evaluate antibiotic resistance and genotyping of a number of gram-negative bacteria (GNB) causing HAI in patients who were referred to Children’s Medical Center.Methods: During the 6-month period, antimicrobial susceptibility profiles of GNB isolates recovered from patients in Children’s Medical Center were determined. Typing of common GNB was performed by random amplified polymorphic DNA (RAPD) analysis and the results were analyzed by Gelcompar II software.Results: In total, 142 (1.1%) gram-negative bacterial strains were isolated, among which 59.2% were from males. The most organisms were isolated from blood (63%) followed by wounds (13.7%). The greatest proportion of strains came from intensive care units (51%). Low sensitivity of Acinetobacter baumannii to common antibiotics and high resistance of Enterobacter spp. To cefotaxime (100%) were reported. The most efficient antibiotics for Escherichia coli strains were amikacin (84%) and gentamycin (81%). However, just 12.5% of Serratia marcescens strains were resistant to trimethoprim-sulfamethoxazole. The analysis of RAPD-typing revealed the presence of one clone in A. baumannii and E. coli and two clones in Klebsiella pneumoniae, whereas the trend varied completely in Pseudomonas aeruginosa strains and Enterobacter spp.Conclusion: The results of this study showed a possibility of an outbreak in the Children’s Medical Center. Since there is a possibility of transmission of an infection from one patient to another, high attention should be paid to the basic methods of preventing infection.Keywords: hospital-acquired infection, gram-negative bacteria, antibiotic resistance

Keywords

• hospital-acquired infection
• gram-negative bacteria
• antibiotic resistance