Mohraz M, Jonaidi N, Rasoulinejad M, Broum M A, Aligholi M , Shahsavan Sh,
Volume 61, Issue 3 (14 2003)
Abstract
Methicillin resistant staphylococcus aureus (MRSA) is a predominantly nosocomial pathogen which its prevalence has increased worldwide over the past three decades.
Materials and Methods: This is a descriptive cross-sectional study. The following study is designed for determination of prevalence of MRSA infection through measurement of MICs of S. aureus isolates in Imam Khomeini Hospital (a teaching hospital) from November 2001 to January 2003. A total number of 402 specimens were isolated and specified as S. aureus by Imam Khomeini microbiology lab. Demographic and clinical data and results of MIC were analysed by Epilnfo 6 software.
Results: During the study, staphylococcus aureus was isolated from 402 patients that 187 (46.5%) of isolates were MRSA and 215 (53.5%) were MSSA. Of 402 patients, 254 (63.2%) were male and 148 (36.8%) were female. The difference of the prevalence of MRSA between males and females was not statistically significant (p= 0.09). The difference in mean age in MRSA and MSSA groups was not statistically significant (p= 0.55). In the age group of < 1 month, the prevalence of MRSA infection was significantly higher than other groups (P= 0.01).
Conclusion: In this study, the prevalence of MRSA infection was increased, statistically significant in the presence of such factors as sepsis, longer duration of hospitalization, hospital- acquired infection, history of invasive procedure, history of antimicrobials used in the past 3 months and type of administered antimicrobial (s), history of hospitalization in the preceding year, certain underlying diseases, type of admission ward, type of infection, type of specimen and type of administered antimicrobials for treatment. Surprisingly, the prevalence of MRSA infection in IV drug user group was low that was statistically significant (p< 0.0001). In this study, there was no statistically significant difference in outcome between MRSA infected and MSSA infected patients. Based on results of this study, prevalence of infections due MRSA in this hospital are high, therefore addition to diagnosis of risk factors of MRSA infections, application of standard infection control practices should be done for limitation of these infections.
Hadadi A, Rasoulinejad M, Maleki Z, Mojtahedzadeh M, Younesian M, Ahmadi S.a, Bagherian H,
Volume 65, Issue 4 (3 2007)
Abstract
Background: The object of this study was to investigate the antimicrobial resistance pattern among common nosocomial Gram-negative bacilli isolated from patients with nosocomial infections.
Methods: From June 2004 to December 2005, 380 isolates of common Gram-negative bacilli (Klebsiella, Pseudomonas, Acinetobacter and E. coli) from 270 patients with nosocomial infections in Sina and Imam Hospitals, Tehran, Iran, were evaluated for susceptibility to Imipenem, Cefepime, Ciprofloxacine, Ceftriaxone and Ceftazidime by Disc diffusion and E-test methods.
Results: The most frequent pathogens isolated were Klebsiella spp. (40%), followed by Pseudomonas (28%), Acinetobacter spp. (20%) and E. coli (12%). The most active antibiotic was imipenem (84%). 26% of all isolates were sensitive to Cefepime, 26% to Ciprofloxacin, 20% to Ceftazidime and 10% to Ceftrixone. The susceptibility rates of Klebsiella to Imipenem, cefepime, ciprofloxacin, Ceftazidime and Ceftriaxone were 91, 25, 21, 13 and 7 percent, respectively and 91, 19, 17, 21 and 21 percent, respectively, for E. coli. Among Acineto- bacter spp., the susceptibility rate was 77% for Imipenem and 21% for Ciprofloxacin. Among Pseudomonas spp., 75% of isolates were susceptible to Imipenem and 39% to Ciprofloxacin. The comparison of the resistance status of microorganisms by both Disc diffusion and E-test methods showed a clinically noticeable agreement between these two tests.
Conclusions: Since antibiotic resistance among Gram-negative bacilli has increased, enforcement of policy regarding proper antibiotic use is urgently needed in order to delay the development of resistance. Although it is widely accepted that E-test is more accurate in determining the resistance of microorganisms, our study showed that the Disc diffusion test will give the same results in most occasions and is therefore still considered useful in clinical practice.
