Methicillin-Resistant Staphylococcus epidermidis in Iran: A Systematic Review and Meta-Analysis

Objective: Methicillin-resistant Staphylococcus epidermidis (MRSE) remains one of the most prevalent drug-resistant bacteria causing health care infections. Limited data are available about how the frequency of MRSE changed in Iran over the past years. The current study aimed at determining the frequency of MRSE in different cities of Iran. Methods: Databases including Web of Sciences, Scopus, Embase, Medline, and Iranian databases were searched to find studies addressing the frequency of MRSE in Iran published from Mar 2006 to Jan 2016. The data were analyzed using comprehensive meta-analysis version 2.2 (Biostat). Of the 139 records identified in the databases, 15 studies met the inclusion criteria. Results: The analyses showed that the frequency of MRSE infections was 73.9% [95% confidence interval (95% CI) 61.4 - 83.4] among culture-positive cases of S. epidermidis in different parts of Iran. The frequency of MRSE was higher in the studies conducted from 2011 to 2015, based on further stratified analyses. Conclusions: The regular surveillance on antimicrobial susceptibility pattern and formulation of definite antibiotic policy may control high rate of MRSE associated infections in Iran. Moreover, rapid and reliable diagnosis of MRSE isolates and regular screening of the personnel and surfaces of hospitals in terms of MRSE are indispensable

Detection of tetracycline resistance genes, aminoglycoside modifying enzymes, and coagulase gene typing of clinical isolates of Staphylococcus aureus in the Southwest of Iran

Objective(s): The aim of the present study was to determine the aminoglycoside modifying enzymes (AMEs) encoded genes, tetracycline resistance genes, and the coa based typing of Staphylococcus aureus isolates in the Southwest of Iran. Materials and Methods: Antimicrobial susceptibility of isolates was carried out by agar disk diffusion methods. Two sets of multiplex PCR mixture were used for detection of AME genes and tet genes.  All of the isolates were typed with the coagulase gene typing method. Of the 121 isolates, 29.75% and 47.93% were resistant to at least one aminoglycosides and tetracyclines, respectively. Results: The aac(6')-Ie-aph(2'') was the most frequent gene (97.22%), and aph (3')-IIIa and ant (4')-Ia genes were detected in 61.11% and 11.11% of aminoglycoside resistant isolates, respectively. The tetK and tetM genes were detected in 82.75% and 56.9% of tetracycline resistant isolates, respectively. Overall 31.4% of isolates were MRSA. Totally 17 distinct coa gene RFLP patterns, numbered C1 to C17, were observed.  The C5 was the most frequent coa type with 31 isolates. Conclusion: The aac(6')-Ie-aph(2'') and aph (3')-IIIa genes were the most important genes contributing to aminoglycosides resistance, while resistance to tetracyclines was mediated by tetK and tetM genes. Interestingly all S. aureus with C5 as the most prevalent coa-type were resistant to at least one of the aminoglycoside antibiotics and tetracycline simultaneously. Moreover, 30 out of 31 isolates with this coa type were MRSA, indicating the importance of the C5 coa-type in MRSA strains and also in isolates that were resistant to aminoglycosides and tetracycline

The frequency of Klebsiella pneumonia encoding genes for CTX-M, TEM-1 and SHV-1 extended-spectrum beta lactamases enzymes isolated from urinary tract infection

Abstract Background The extended- spectrum β-lactamase producing bacteria are widely spread worldwide. The productions of these enzymes cause bacterial resistance to a wide range of antibiotics. The aim of this study was to investigated the frequency of K. pneumonia encoding genes for CTX-M, TEM-1 and SHV-1 extended-spectrum beta lactamases enzymes isolated from urinary tract infection. Methods This study is cross-sectional study. All K. pneumonia isolates from urine samples, which had grown on media culture more than 105 were delivered to the medical microbiology laboratory. K. pneumonia susceptibility of 198 samples were confirmed by disk diffusion. The gene frequency of genes was determined using PCR, and analyzed using SPSS version 21 software. Finding Most of the K. pneumonia isolated from urine producing β-lactamase were resistant to cotrimoxazole (53.2%) followed by cefotaxime (50%), ceftazidime, ceftriaxone (40.3%), nalidixic acid (17.8%), amikacin and imipenem (1.6%) and meropenem (0%) respectively. Out of the 198 confirmed isolates of K. pneumonia, 62 cases (31.3%) have the gene phenotype of broad spectrum β-lactamase enzymes and highest frequency of gene phenotype was related to the SHV-1 gene (85.5%). Then in the terms of abundance from highest to lowest CTXM-3 (56.5%), CTXM-1 (27.4%), TEM-1 (16.1%) and CTXM-2 (8.1%), were respectively. Conclusion This study showed that K. pneumonia isolated from urine producing β-lactamase were resistance to a wide range of antibiotics. Due to the increasing resistance of most antibiotics, control and supervision in the use of antibiotics and identification of broad spectrum β-lactamase enzymes by phenotypic methods appears to be essential