Nosocomial Gram-Negative Microorganisms: What Changed Over a 10-Year Period?

• Main Authors: Murat DİZBAY, Derya TOZLU KETEN, Dilek ARMAN
• Format: Article
• Language: English
• Published: Bilimsel Tip Yayinevi 2010-09-01
• Series: Flora Infeksiyon Hastalıkları ve Klinik Mikrobiyoloji Dergisi
• Subjects: Drug resistance; Bacterial
• Online Access: http://www.floradergisi.org/getFileContent.aspx?op=REDPDF&file_name=2010-15-3-105-111.pdf

Introduction: In this study, the changes in the epidemiology and resistance profiles among nosocomial gram-negative microorganisms over a 10-year period were compared. Materials and Methods: The surveillance data accumulated in Gazi University Hospital during the periods January-July 1998 and January-December 2008 were compared. Nosocomial gram-negative microorganisms were obtained from the clinical specimens of the patients. The clinical and laboratory data of the patients were obtained from patient files, fever and drug charts and clinicians. Only the isolates related to nosocomial infections were included in the study. Antimicrobial susceptibility tests were performed by agar dilution method in 1998 and by disk diffusion test in 2008. Results: 251 gram-negative microorganisms isolated in 1998 and 888 isolated in 2008 were included in the study. The most frequently isolated microorganisms were Escherichia coli, Pseudomonas spp., Acinetobacter baumannii and Klebsiella spp. in 1998 and A. baumannii, E. coli, Pseudomonas spp. and Klebsiella spp. in 2008. An increase in the frequency of Acinetobacter isolates and a decrease in Pseudomonas and E. coli isolates were found to be statistically significant between 1998 and 2008. The percentages of gramnegative microorganisms isolated from intensive care units were 42% and 70% in 1998 and 2008, respectively. The most frequently seen nosocomial infection type was urinary tract infection in 1998 and pneumonia in 2008. Antimicrobial susceptibility test results revealed a statistically significant increase in resistance rates among the gram-negative microorganisms, especially in the Acinetobacter species, between 1998 and 2008. Conclusion: The frequency of Acinetobacter infections significantly increased over the study period. An increasing number of intensive care unit beds in our hospital resulted in changes in the frequency of nosocomial pathogens and nosocomial infection types, as well as a remarkable increase in resistance rates to antibiotics. The rapid development of antibiotic resistance among the gram-negative microorganisms, including to new antibiotics, necessitates the application of proper infection control measures and rational antibiotic use.