Antimicrobial susceptibility patterns among bacteria isolated from intensive care units of the largest teaching hospital at the northwest of Iran

Abstract

This study was conducted to determine the antimicrobial susceptibility patterns among common pathogens in the intensive care units (ICUs) of a university hospital in northwestern Iran. A retrospective study was done on laboratory records of patients with nosocomial infection who were admitted to five ICUs of Imam Reza Hospital during a 21-month period from March 2010 to January, 2012. A total number of 556 isolates from 328 patients were evaluated. The most common sites of infections included respiratory (51.7%), urinary (24.8%), and blood (10.4%). The most frequently isolated microorganisms were Enterobacter aerogenes (50.6%) followed by Escherichia coli (16.7%) and Pseudomonas aeruginosa (7.5%). Staphylococcus aureus was the most frequent pathogen among gram-positives (39.7%). The rate of methicillin-resistant Staphylococcus aureus (MRSA) was 87.5%. Multidrug-resistant (MDR) gram-negative bacteria were documented in 25.8% of Acinetobacter, 20% of Klebsiella, and 16.6% of Pseudomonas. The most active antimicrobials were vancomycin (93.5%) followed by amikacin (71.5%) and gentamicin (46%). The overall antibiotic susceptibility was as follows: 36% ciprofloxacin, 19% imipenem, 20% trimethoprim-sulfamethoxazole, 20.5% ceftazidime, and 12% ceftriaxone. Due to the high rate of antimicrobial resistance in the ICU setting, more surveillance and control of the use of antimicrobials is needed to combat infections. Uniterms:Intensive care units/anti-infective agents/cross infection. Hospital University/Iran. INTRODUCTION Patients a d m i t t e d t o intensive care units (ICUs)are more vulnerable to various nosocomial infections because of their underlying illnesses and exposure to various invasive medical devices (Jatin, Mary, 2012;Archibald et al., 1997;Fridkin, 2001;Kollef, Fraser, 2001;Rhomberg et al., 2006).Hospital infections affect approximately two million patients annually and lead to 90,000 deaths and a cost of $4.5 to $5.7 billion according to reports from the United States (Weinstein, 1998;Jarvis, 2001). They involve 5-10% of ICU patients (CDC, 1992;Stone, Larson, Kawar, 2002).Antibiotics are the mainstay tools in the management of infections. Disappointingly, a number of studies have reported inappropriate uses of antimicrobials as well as the emergence of antibiotic resistance in most parts of the world (Tunger et al., 2009; Bergman et al., 2006). Today, the emergence of multidrug-resistant (MDR) gramnegative and methicillin-resistant Staphylococcus aureus (MRSA) pathogens has become a major public health concern. Moreover, they negatively influence patients' outcomes and increase the length of hospital stays and healthcare costs (Giske et al., 2008;De Kraker et al., 2011;Resch, Wilke, Fink, 2009;Mulvey, Simor, 2009).Many studies have also showed that controlled use of antibiotics leads to improved microorganism sensitivity H. Hamishehkar, P. Shadmehr, A. Mahmoodpoor, S. O. Mashayekhi, T. Entezari-Maleki 404 to antimicrobial agents (Lee et al., 2010;Takesue et al., 2010). The emergence of resistant pathogens ...

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“…Consistent with our study, other investigators have reported also as the most common site of infection respiratory tract, urine and blood [3,7,12].…”

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The Characterization of Antibiotic Resistance of Bacterial Isolates from Intensive Care Unit Patient Samples in a University Affiliated Hospital in Romania

“…Consistent with our study, other investigators have reported also as the most common site of infection respiratory tract, urine and blood [3,19,[25][26][27].…”

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