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Background and purpose: Nosocomial infections are a major health problem worldwide. Hospital environment is a reservoir for nosocomial pathogens. This study aimed at determining the prevalence of antimicrobial resistance pattern of bacteria isolated from the environment and medical equipment in Valiasr Hospital in Arak. Material and Methods: A total of 210 samples was collected from hospital and identified. Inducible clindamycin resistance in Staphylococcus was determined with D Zone and sensitivity to vancomycin was identified by using Mueller Hinton agar and E-test. The sensitivity of these strains to cefoxitin and oxacillin was determined by disk diffusion method. The resistance was confirmed by investigating the presence of mec A gene using PCR technique. To identify the ESBL producing gram-negative bacill standard method was used. Amp C beta lactamase resistance was assessed by Amp C disk test, and for carbapenemase resistant MHT was applied. E-test with imipenem and imipenem+EDTA were used to identify the resistance pattern of metalo beta lactamase. Results: There were 240 isolates of which 185 (77%) were Staphylococcus. Among these isolates 136 (73.5%) were resistant to oxacillin and cefoxitin. Inducible clindamycin resistance was found in 46 (25%) isolates. Two samples of the Staphylococcus epidermidis were vancomycin resistant. The presence of Sa442 genes in Staphylococcus aureus and the mecA gene of MRSA was confirmed in all isolates expect in two. The frequency of gram-negative bacteria was 55(23%). ox51 gene was identified in acinetobacter baumannii. Fifteen nonfermenting gram-negative bacill and 40(65%) strains of Enterobacteriaceae were ESBL producers. Among the Klebsiella pneumoniae six (33.33%) were AmpC producers. MHT positive was found in nine (60%) nonfermenting bacills. Conclusion: According to this study presence of microorganisms in Valiasr Hospital environment and high incidence of antibiotic resistance are considered as major health problems. By determining potential pathogens in hospital setting and the pattern of antibiotic resistance markers physicians can perform more successful treatments.

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Background and purpose: Appropriate and efficient disinfection is an important aspect of hospital infections control. The aim of this study was to investigate the effects of common disinfectants used for Escherichia coli bacteria separated from two teaching hospitals in Sari, 2014. Materials and methods: Escherichia coli were taken from different wards in Zare and BouAli hospitals. E.Coli was identified by standard plant methods, differential test and biochemical isolation. Deconex plus53, Creolin and Cidex were used as disinfectants in various concentrations. Their effects were determined by Standard disc diffusion method. Data was analyzed using regression in Minitab V.17. Results: A total of 120 samples were investigated of which 48 (40%) were found contaminated and 15 (13%) of these isolates were positive for E.coli. The most effective disinfectants against E.coli were Cidex 2%, deconex Plus53 2%, and Creolin 3.5%, respectively. Conclusion: Performing pretests is necessary for choosing the most appropriate disinfectant and increasing its efficacy. Also, it is important to consider common infectious bacteria in hospitals and effective factors on disinfectants such as concentration and time.

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Background and purpose: Nosocomial infections are among the main causes of death among hospitalized patients. Successful control of these infections requires awareness on their prevalence and taking preventive measures in hospitals. This study aimed at determining the prevalence of hospital-acquired infections in Mazandaran province. Materials and methods: A descriptive-longitudinal study was performed in 15 hospitals in Mazandaran province that record their infection rates in NISS software. Data was analyzed at the significance level of 0.05 using SPSS and STATA software. To investigate the relationships between different variables crosstabs and Poisson regression were applied. Results: The mean ages of infected male and female were 54.53±0.67 and 49.2±0.63 years, respectively (P<0.05). The amount of infections in the 15 hospitals in 2011 was 79% and in 2012, it was 1.21%. The highest incidence of infections was due to pneumonia, urinary infection, surgical incisions, and burn wounds. The majority of infections were caused by Escherichia coli (E. coli) (12.3%), Pseudomonas aeruginosa (6.3%), Acinetobacter (6.1%), and Klebsiella (5.9%). A significant relationship was observed between an underlying disease and various types of infections (P<0.05). The risk of hospital infections in women was 1.09 times more than men (P=0.918). Conclusion: The risk of infection was not significant among women and men. Having a background disease affects the kind of infection. The incidence of infection showed an increase in 2012 compared to 2011..

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Background and purpose: Multiple drug resistance in Enterobacteriaceae has restricted the available options for treatment of infections caused by these bacteria. The aim of this study was to investigate the pattern of multidrug resistance and cross-resistance in Enterobacteriaceae causing nosocomial infections in intensive care units during 2014-2015 in eighteen governmental hospitals in Mazandaran province, Iran.

Materials and methods: A cross-sectional descriptive study was performed in which antibiotic susceptibility test to routinely antibiotics was determined by MIC method and "broth micro-dilution” was done according to CLSI.

Results: A total of 35 strains including Klebsiella pneumoniae (24), Escherichia coli (6), and Enterobacter spp (5) were extended-spectrum β-lactamases producer. The prevalence of multidrug resistance in Klebsiella pneumoniae, Escherichia coli and Enterobacter spp were 95.83%, 66.6%, and 80%, respectively. Among the isolates 28.57% exhebited cross-resistance to aminoglycoside antibiotics and 40% were found with cross-resistance to third- and fourth-generation cephalosporins.

Conclusion: Regarding the high prevalence of multidrug resistance and the emergence of cross-resistance to different categories of antibiotics among Enterobacteriaceae causing nosocomial infection, more effective measures should be taken including implementation of infection control programs, isolation of patients infected by multidrug resistance bacteria, and antibiotic stewardship in hospitals.

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 Over recent years, nosocomial infections, and the morbidity and mortality associated with pathogenic bacteria have dramatically increased due to antibiotic resistance and imposed significant burdens on the global health system. Critical shortage of effective therapeutics against multidrug-resistant bacteria highlights the need for development of novel antibiotics. Actinobacteria are well-known sources of natural bioactive compounds, especially antibiotics. Nearly two-thirds of the antibiotics on the market have actinobacterial origins. Endophytic actinobacteria residing within plants contribute to the plant growth and survival by producing plethora of secondary metabolites. Therefore, isolation, cultivation, and identification of new strains, as well as their potential to produce antimicrobial compounds, are of great importance. Lack of published research in this field highlights the importance of this review in Iran. The aim of this review was to present the latest methods for the isolation and identification of endophytic actinobacteria and introducing relevant databases. We also studied the most recent isolated strains, chemical structure of 51 newly identified secondary metabolites, and their potential medical-pharmaceutical applications. This study revealed that endophytic actinobacteria are prolific sources of bioactive secondary metabolites with high levels of structural diversity and potent pharmaceutical and medicinal applications.

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 Background and purpose: Hospital infections are one of the major challenges that health systems are faced with, leading to economic, social, and psychological damages. Clinical staff play an important role in controlling nosocomial infections, so, this study was conducted to design a standard questionnaire to assess the knowledge, attitude, and practice of clinical staff about nosocomial infections.
Materials and methods: A mixed method confirmatory study was performed to develop an instrument in Tehran, Iran 2019. The items of the questionnaire were extracted for clinical staff by searching electronic databases, including SID, Magiran, PubMed, Scopus, Science Direct, and Google Scholar. The initial questionnaire was designed and its validity was assessed by 10 experts in hospital infection control. To assess construct validity, the questionnaire was completed by 180 clinical staff working in hospitals in Tehran. Cronbach's alpha and retest were used to assess the reliability of the scale.
Results: The Content Validity Index and Content Validity Ratio for the questionnaires in three domains of awareness, attitude, and performance ranged 0.8-1. The face validity of the questions ranged 2.1-4.5. In Knowledge about nosocomial infection, Richardson's coefficient was 0.75 and Cronbach's alpha of attitude and practice were 0.71 and 0.82, respectively. Pearson correlation coefficient obtained in retest for knowledge, attitude, and performance were 0.91, 0.85, and 0.92, respectively. Three-factor confirmatory analysis showed that the questionnaire has a good fit.
Conclusion: The questionnaire designed for clinical staff has good validity and reliability which is suggested as a valid questionnaire in future researches.

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Background and purpose: The term nosocomial infection refers to any type of infection that does not exist at the time of hospital admission and occurs within 48-72 hours after admission or up to 3 days to 6 weeks after discharge, or 30 days after surgery. Nosocomial infections can cause side effects, mortality and reduce quality of life in patients. So, so we decided to study the clinical, laboratory, and microbiological characteristics of patients with heart disease and nosocomial infections in Sari Fatemeh Zahra Hospital.
Materials and methods: In this descriptive study, 22811 people were studied. Information were recorded, signs of infection in patients were reviewed and in case of symptoms, patients were further examined. Data analysis was performed in SPSS ver.18.
Results: In this study, 1.4% of patients developed nosocomial infections. The mean age of patients was 64.5±12.5 years and the majority of patients were males (53.3%). The most common underlying diseases were hypertension, diabetes, and hyperlipidemia. The most common type of nosocomial infection was respiratory infection (47.8%) and the most common bacteria found in culture medium was Escherichia coli. Acinetobacter was resistant to all antibiotics tested except colistin which was susceptible in 80% of cases and resistant in 20%.
Conclusion: Control and prevention of nosocomial infections is of particular importance, especially in patients admitted to intensive care units after heart surgery.

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Background and purpose: Nosocomial infections, especially in the intensive care unit (ICU), are critical medical problems worldwide, increasing the length of hospital stay, treatment costs, and mortality. The present study aimed to assess the prevalence of mortality caused by hospital infections in patients admitted to the ICU of Imam Khomeini Hospital, Sari.
Materials and methods: The cross-sectional descriptive study was conducted on 289
patients admitted to the ICU of Imam Khomeini Hospital, Sari, from 2019-2020. Culture reports (positive/negative), detected microorganisms, antibiotic sensitivity, and cases of mortality were recorded and evaluated in the checklist.
Results: Among 289 patients, 112 cases were female, and 177 subjects were male. The mean age of the deceased was 63.10±14.11 years. According to the data, 86% of patients recovered and 14% died. The most common cause of nosocomial infection was Enterobacter (17.3%), and the most common nosocomial infection was pneumonia (45.3%). The majority of patients who died had taken ceftriaxone.
Conclusion: Identification of factors related to increased mortality in patients with nosocomial infections can have a significant function in the management and control of hospital infections. In the present study, multiple drug resistance in pathogens was high. The highest mortality rate was related to Stenotrophomonas maltophilia infection.

 

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Background and purpose: Hospital infections remain a significant health concern despite advancements in treatment methods. The emergence and spread of pathogens with multiple resistance remain a global health issue. The purpose of this study was to investigate the prevalence of nosocomial infections and determine the antibiotic resistance pattern in Razi Ghaemshahr Hospital, Mazandaran.
Materials and methods: This descriptive cross-sectional study was carried out at Razi Ghaemshahr Hospital in Mazandaran province during 2016-2017. Positive cultures from hospitalized patients were used as samples and subjected to antibiotic resistance pattern analysis using the disk diffusion method.
Results: Out of the 672 hospitalized patients in different wards, the infectious ward had the highest frequency distribution of patients (40%). The most commonly isolated pathogens were Escherichia coli (26.2%), Acinetobacter baumannii (14.7%), Enterobacter (14.1%), Pseudomonas aeroginosa (13.5%), and Citrobacter (12.8%). The pathogens were highly resistant to cephalosporins, fluoroquinolones, beta-lactamase inhibitors, and carbapenems.
Conclusion: It was found that the most frequently isolated pathogen was Escherichia coli. The emergence of Citrobacter with high antibiotic resistance can possibly be attributed to a shift in the prevalence pattern of microorganisms within this hospital