High frequency of methicillin-resistant Staphylococcus aureus (MRSA) with SCCmec type III and spa type t030 in Karaj's teaching hospitals, Iran.

Methicillin-resistant Staphylococcus aureus (MRSA) has been one of the most important antibiotic-resistant pathogen in many parts of the world over the past decades. This cross-sectional study was conducted to investigate MRSA isolated between July 2013 and July 2014 in Karaj, Iran. All tested isolates were collected in teaching hospitals from personnel, patients, and surfaces and each MRSA was analyzed by SCCmec and spa typing. Antibiotic susceptibility testing was accomplished by disk diffusion method. Out of 49 MRSA isolates from the Karaj's teaching hospitals, 82%, 10%, and 6% of the isolates were SCCmec types III, II, and I, respectively. The main spa type in this study was spa t030 with frequency as high as 75.5% from intensive care unit (ICU) of the hospitals and high rate of resistance to rifampicin (53%) was found in MRSA isolates. In conclusion, high frequency of spa t030 with SCCmec type III and MRSA phenotype illustrated circulating of one of the antibiotic-resistant strains in ICU of Karaj's teaching hospitals and emphasizes the need for ongoing molecular surveillance, antibiotic susceptibility monitoring, and infection control.

Epidemiological and Inducible Resistance in Coagulase Negative Staphylococci.

BACKGROUND & OBJECTIVES: Coagulase negative staphylococci (CNS) are potential pathogens with the increased use of implants in hospitals. Macrolide, lincosamide and streptogramin B (MLSB) are used in the treatment of staphylococcal infections. The aim of this study was to molecular detection of inducible clindamycin resistance and genetic pattern in CNS isolates and their transmission between hospitals. MATERIALS & METHODS: 110 CNS strains, isolated from hospitalized patients in the intensive care unit and infectious wards of Besat and Toohid hospitals, Sanandaj. Methicillin resistance was done by agar screen test and the resistance inducible Clindamycin by the D-Test. Multiplex PCR was performed, using primers specific for erm (A, B, C, and TR) genes. Diversity of strains was determined by ERIC-PCR technique based on the similarities between DNA fingerprints by using Jaccards coefficient in the SAHN program of the NTSYS-pc software. RESULTS: Of the 110 isolates, 64(58.2%) were methicillin -resistant CNS (MRCNS), 48(43.6%) were resistant to erythromycin (ERCNS). Out of 48 Erythromycin-resistant strains 5 (10.4%) were iMLS B phenotypes that 4 isolates showed genes erm by Multiplex PCR. The ERIC-PCR profiles allowed typing of the 110 isolates into 90 ERIC-types which were grouped into fourteen main clusters (C1-C14). CONCLUSION: The results of this study also showed that most of CNS isolated produced different genomic fingerprint patterns, therefore, source of infection is differen t.

Antimicrobial Resistance Patterns and Prevalence of blaPER-1 and blaVEB-1 Genes Among ESBL-producing Pseudomonas aeruginosa Isolates in West of Iran.

BACKGROUND: Pseudomonas aeruginosa is a leading cause of nosocomial infections worldwide. Resistance of P. aeruginosa strains to the broad-spectrum cephalosporins may be caused by extended-spectrum ß-lactamases (ESBLs). OBJECTIVES: The aim of this study was to determine the antimicrobial resistance patterns and prevalence of PER-1 and VEB-1 type genes among ESBL producing strains of P. aeruginosa. MATERIAL AND METHODS: A total of 106 P. aeruginosa isolates were collected from two university hospitals in Hamadan, Iran, during a7-month study (2009). The antimicrobial susceptibility of isolates was determined by disc diffusion method and interpreted according to the clinical and laboratory standards institute (CLSI) recommendations. Production of ESBL was determined by combined disk test and presence of PER-1 and VEB-1 type ESBL genes was identified by PCR. RESULTS: The resistance against broad-spectrum cephalosporins and monobactames were: cefepime (97%), cefotaxime (92.5%) ceftazidime (51%), and aztreonam (27%). Ciprofloxacin (91.5%), imipenem (84.9%) and meropenem (82.1%) were the most effective anti-pseudomonas agents in this study. The results revealed that 88.7% of the isolates were multidrug resistant, 58.25% of those were ESBL positive. Sixteen (26.6%), 9 (15%) and 3 (5%) strains among ESBL-producing strains contained blaPER-1, blaVEB and blaPER-1-blaVEB, respectively. CONCLUSIONS: This study highlighted the need to establish antimicrobial resistance surveillance networks for P. aeruginosa to determine the appropriate empirical treatment regimens. The high prevalence of multidrug resistance and production of ESBLs in P. aeruginosa isolates confirms the necessity of protocols considering these issues in the hospitals.

Prevalence of Salmonella spp. in Packed and Unpacked Red Meat and Chicken in South of Tehran.

BACKGROUND: Despite of the advances in infectious diseases prevention and food technology, food-borne diseases are considered major problems in developed and developing countries. Meat plays a key role in transferring zoonotic diseases to human. OBJECTIVES: This study was conducted in south of Tehran, Iran, to investigate the prevalence rate of Salmonella spp. in packed and unpacked red meat and chicken. MATERIALS AND METHODS: A total of 379 packed and unpacked samples including 189 red meat and 190 chicken samples were collected randomly. From each sample, 25 g was separated and treated with 225 mL of buffered peptone water, homogenized and incubated at 37°C for 24 hours. Samples were enriched using Rappaport-Vassiliadis broth and then streaked onto Hektoen enteric agar. RESULTS: Totally, 86 out of 190 chicken and 38 out of 189 red meat samples were contaminated with Salmonella spp. The most isolated serotypes were Salmonella thompson (67.7%), S. heaardt (6.5%), S. enteritidis (4.8%), and S. veyle (4%), respectively. In general, the rate of chicken contamination was higher than meat, as 43.3% of packed and 46% of unpacked chicken samples were contaminated. CONCLUSIONS: These results confirmed the pervious findings, stating that proper packaging of meat products can effectively decreases the rate of microbial contaminations.

Effect of Helicobacter pylori infection on stromal-derived factor-1/CXCR4 axis in bone marrow-derived mesenchymal stem cells.

BACKGROUND: Recent studies have demonstrated that during chronic Helicobacter pylori (H. pylori) infection bone marrow-derived-mesenchymal stem cells (BMD-MSCs) migrate to the gastric tissue and could be also the origin of gastric adenocarcinoma. The chemokine CXCR4 through binding to its ligand stromal-derived factor (SDF-1) plays a crucial role in migration of inflammatory and stem cells. However, the possible effect of H. pylori infection on the SDF-1/CXCR4 axis has not yet been elucidated. MATERIALS AND METHODS: Gastric epithelial cell line, AGS, and BMD-MSCs were cocultured with H. pylori for 24 h. The expression of CXCR4 was examined in BMD-MSCs by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and flow cytometry, and SDF-1 expression in AGS cells was detected by qRT-PCR and enzyme-linked immunosorbent assay. Further, migration of BMD-MSCs toward SDF-1 was evaluated by chemotaxis assay. RESULTS: We found that coculture of H. pylori with BMD-MSCs or AGS: (i) enhanced CXCR4 expression on the cell surface of BMD-MSCs and (ii) increased SDF-1 secretion by AGS cells. Consistently, we observed that H. pylori-treated BMD-MSCs showed a higher capability to migrate toward SDF-1 gradient compared with untreated cells. CONCLUSION: We found that H. pylori upregulates CXCR4 expression in BMD-MSCs and enhance their migration toward SDF-1. This study provides the first evidence that H. pylori infection may enhance BMD-MSC migration through acting on the SDF-1/CXCR4 axis.

Pseudomonas aeruginosa, an emerging pathogen among burn patients in Kurdistan Province, Iran.

This study was conducted to determine the incidence of Pseudomonas aeruginosa infections among burn patients at Tohid Hospital, Iran. A total of 176 clinical specimens were obtained from 145 burn patients admitted to the burn unit of Tohid Hospital to detect the presence of P. aeruginosa. Antimicrobial susceptibility testing was conducted to detect extended spectrum beta-lactamase (ESBL) producing P. aeruginiosa using Clinical and Laboratory Standards Institute guidelines with the double disc synergy test (DDST). A polymerase chain reaction was used to detect PER-1 and OXA-10 among the isolates. The mean age, total body surface area and length of hospital stay among patients were 29 years, 37.7%, and 10 days, respectively. Kerosene was the commonest cause of burn (60%), followed by gas (30%). During the study, P. aeruginosa was detected in 100 isolates. The antibiotics they were most commonly resistant to were cefotaxime, ceftriaxone and ciprofloxacin. Of the 100 P. aeroginusa isolates, 28% were positive for ESBL production with the DDST, 48% and 52% were PER-1 and OXA-10 producers, respectively. The high frequency of PER-1 and OXA-10 producers at this hospital is of concern considering their potential spread among burn patients.

Bacterial infections in burn patients at a burn hospital in Iran.

BACKGROUND & OBJECTIVE: The major challenge for a burn team is nosocomial infection in burn patients, which is known to cause over 50% of burn deaths. Most studies on infection in burn patients focus on burn wound infection, whereas other nosocomial infections in these patients are not well described. We undertook this study to determine three types of nosocomial infections viz., burn wound infection, urinary tract infection, and blood stream infection in burn patients in a burn hospital in Iran. METHODS: During the one year period (May 2003 to April 2004), 182 patients were included in this study. Blood, urine and wound biopsy samples were taken 7 and 14 days after admission to Taleghani Burn hospital. Isolation and identification of microorganisms was done using the standard procedure. Disk diffusion test were performed for all the isolates for antimicrobial susceptibility. RESULTS: Of the 182 patients, 140 (76.9%) acquired at least one type of infection of the 140, 116 patients (82.8%) were culture positive on day 7 while 24 (17.2%) on 14 days after admission. Primary wound infection was most common (72.5%), followed by blood stream (18.6%) and urinary tract infections (8.9 %). The microorganisms causing infections were Pseudomonas aeruginosa (37.5%), Staphylococcus aureus (20.2%), and Acinetobacter baumanni (10.4%). Among these isolates P. aeruginosa was found to be 100 per cent resistant to amikacin, gentamicin , carbenicillin, ciprofloxacin, tobramycin and ceftazidime; 58 per cent of S. aureus and 60 per cent of coagulase negative Staphylococcus were methicillin resistant. INTERPRETATION & CONCLUSION: High prevalence of nosocomial infections and the presence of multidrug resistant bacteria, and methicillin resistant S. aureus in patients at Taleghani Burn Hospital suggest continuous surveillance of burn infections and develop strategies for antimicrobial resistance control and treatment of infectious complications.