دو ماهنامه میکروب شناسی پزشکی ایران
سال هشتم شماره 4 (زمستان 1393)

The variation of reported nosocomial infection is very high respectively. It seems review systematic and Meta analysis of related documents gives precise estimate of this subject for correct politisize. So tha aim of this study the review systematic and meta analysis of prevalence and causes of nosocomial infection in iran. For this study all articles published in Iranian journals and international journals، Final Report of Research Projects، related papers presented at congresses and thesis were reviewed with using standard and sensitive keywords. Then، all articles published between 1997-2010 years that had eligibility Inclusion criteria after quality control، using random model، intered to process of meta-analysis. The finding show that the best estimate of total prevalence of nosocomial infection in Iran is 30. 43% and the most common infections of nosocomial infection are respiratory infection 39. 4%%، urinary infection 23. 88%، bacteremia 21. 98% and the most common factors of nosocomial infection are Pseudomonas aeroginosa 26. 78%، klebsiella 31. 42%، Staphylococcus 23. 6% and E. coli 30. 93%. The research also found a substantial heterogeneity that using meta regression method the main cause of produce of this heterogeneity، participants people، sample size، average age of the samples، time of study and gender were introduced. The simple review of studied documents in this survey show that prevalence rate of different nosocomial infection in Iran is high relatively. Hence make appropriate and evidence-based educational and control programs to reduce nosocomial infections prevalence rate in Iran should be considered by policy makers.

Listeria monocytogenes cause listeriosis and fatal infections in humans. The aim of this study was typing and evaluation of the genetic relatedness of L. monocytogenes strains from food samples using MLVA technique. 317 food samples were collected from 2009 to 2013 in Tehran,Iran. After final diagnosis of L. monocytogenes DNA was extracted to perform of MLVA technique, and also PCR products were analyzed by Gene Tools software. The number of tandem repeats was determined by using special equation for each selected locus. Also typing of strains was done. 24 samples of 317 food samples were positive for L. monocytogenes using standard laboratory techniques. A total 13 different types were determined by MLVA technique that type 2 and type 3 were the most abundant types by 6 and 4 strains, respectively. The results of this study showed the presence of L. monocytogenes in dairy products and meat samples, therefore all people, especially pregnant women should observe health tips when using these products. The results of typing showed that L. monocytogenes strains from different sources can have the same origin. MLVA technique is easy with high accuracy and this method can be used in typing and evaluation of the genetic relatedness of L. monocytogenes for determination the source of contamination.

The epidemiologic pattern of Helicobacter pylori infection is differed between developed countries and developing countries, and also it is depend on the total standard of living in each region. At the present study, the seroprevalence of H.pylori infection and effectiveness of underlying factors in prevalence of this infection among residents of Pishva city of Varamin was evaluated. This descriptive study was conducted after completion the questionnaire. The peripheral blood of 314 people without any confirmed gastric problem were collected. Then, the titer of total IgG and IgG anti CagA of H. pylori was evaluated by ELISA method. Consequently, the correlation between serologic data and different factors were analyzed by SPSS statistical software. The existence of total IgG was detected in 164 (55.2%) of 314 patients and was negative in 130 people (41.4%).Also, the IgG anti CagA were positive in 46 (29.1%), it was negative in 105 people (66.5%) and the rested were in borderline. There was statistical meaningful correlation between positive result of serology test of IgG anti CagA to some risk factors such as age, the number of the member of family, the educational status and occupation, the consumption of can, heart diseases, the rate of cholesterol, the history of gastrointestinal symptoms, heartburn and reflux (P <0.05). With regard to high prevalence of H. pylori in this area (55.2%) and its presumptive effect in infected people, the necessary of hygiene education and precise control of infection is suggested.

According to numerous reports of infections caused by spectrum beta lactamases (ESBLs) producing Acinetobacter baumannii in our country in recent years, this study was performed to define the antibiotic susceptibility patterns and detect the prevalence PER and VEB beta-lactamase genes among A.baumannii isolated from patients in Tehran by PCR. 100 A.baumannii clinical isolates collected from various hospitals in Tehran during a year, using special culture media and biochemical tests were identified. The antibiograms of the isolates against 11 antibiotics by disk diffusion method (Disk diffusion) according to Clinical and Laboratory Standards Institute (CLSI) guidelines was performed. Then minimum inhibitory concentrations (MIC) was determined for cefepime and ceftazidime and for the identification of ESBL-producing strains was used in combination disk method, and finally to assess the prevalence of PER and VEB beta-lactamase genes using specific primers PCR was performed. Antibiograms results showed that the greatest resistance to the antibiotics amikacin, cefepime, and less resistance to polymyxin B were obtained. Rates of multi-drug resistant strains of about 70% was achieved. Of the isolates studied, the MIC of ceftazidime in 84% and for cefepime in 91% were ≥ 128 μg/ml. The results of the combined-disk test demonstrated that 20% of samples were ESBL positive. The PCR results showed that 47% and 32% of our isolates had PER and VEB genes respectively. Regarding to existence of PER and VEB genes in this bacterium and possibility of transformation of these genes to the other bacteria, reconsideration in antibiotics consumption patterns and more attention to nosocomial infections control criteria are inevitable.

Pseudomonas aeruginosa is a unique bacteria that in order to survive in different environments by complex adaptation process can make changes in his virulence genes expression and drug resistance. The aim of this research is the investigation of existence of a logical association between toxA gene and antibiotic resistance in strains possess the gene. Antibiogram test by disk diffusion method (Kirby Bauer) was performed according to CLSI protocols. In this study, the existence of toxA gene with the help of polymerase chain reaction (PCR) in 102 clinical isolates from blood samples, wound, urine and trachea was examined. Chi-square test was used to investigate the relationship between exotoxin A and antibiotic resistance. The 81 strains (79.4%) had toxA gene. Frequency of toxA genes in isolated strains from different infections were wound (91.4%), blood (85.7%), trachea (72.7%), and urine (42.1%). Multiple resistance index in strains possess the toxA gene was calculated 75%. Chi 2 test to determine the relationship between drug resistance and gene toxA was significant (P<0.05). The significant chi-square test and an increase in multi-resistant strains possessing the toxA gene, can represent a considerable genetic switch between exotoxin A activity and resistance to antibiotics in the blood, urine, tracheal, wound infections Respectively, which lead to turn genes on of drug resistance regulating in bacteria. The results of this study will be verified by southern blot, analysis of the expression of toxA gene and determine the mechanism of resistance in resistant strains Methods.

The main principle of ensuring the health and pharmaceutical medicine.In accordance with its combination of drugs can be the perfect environment for growth of microorganisms.The aim this research was to identify microorganisms in raw materials, water and environment, and other antimicrobial disinfectant effect of in eliminating them. In this descriptive study, 5 step 52 series production of gastric juice manufacturing factory sampling was performed before and after sterilization.Plate count method was used to measure microorganisms. If there is contamination of the culture media and biochemical tests for the detection of specific microorganisms such as Staphylococcus aureus, E.coli, Pseudomonas aeruginosa, Aspergillus niger and Salmonella spp. were used. The result showed that Micrococcus in 3 cases, 2 cases of Serratia spp., Bacillus subtilis, in two instances, in one instance, Salmonella spp., S. aureus and A.niger in one sample were present in one sample. The experiments showed that the infected samples 19.2% are. 13.5%, which includes microorganisms, non-pathogenic, with over 100 CFU/ml are 5/7% of the sample remained, including microorganisms, virulence such as S. aureus, 1.1%, Salmonella 1.1% the A.niger and 1.1% respectively.

Alkaline proteases are used in pharmaceutical, film and photography, silk production and food, leather and detergent industries. Actinomycetes are gram positive bacteria that produce different enzymes such as proteases. The aims of this research were isolation of native alkaline protease-producing Actinomycete spp. from different soil samples as well as optimizing the conditions for enzyme production. The different soil samples were collected from different locations of the provinces of Khouzestan, Chahar Mahalo Bakhtiari and Isfahan, Iran. After determining of the best alkaline protease producing species using Lowry method, the optimization of alkaline protease was performed. The alkaline protease producing Actinomycete spp. was isolated from soil. The most enzyme activity was measured in S.diastaticus. The best concentration of sucrose as the carbon source for the highest production of alkaline protease was 10 g/l. The optimum pH and temperature for the alkaline protease production by S. diastaticus were 10 and 30°C respectively. The maximum activity of alkaline protease was measured at 200 rpm as the best aeration speed. This is the first report of alkaline protease production by Streptomyces diastaticus in Iran. The accomplished examinations in this research confirmed the previous theories of alkaline protease production by Actinomycetes relatively. Regarding the immense applications of alkaline proteases in several industries and isolation of a native alkaline protease producing Actinomycete, The production potential of this enzyme in our country could be accessible in the near future.

This project focuses on the level of heterotrophic baceria in bottled mineral water which could be a health concern for the elderly, infants, pregnant women and immuno-compromised patients. Different brands of bottled water samples were selected randomly and evaluated for their bacteriological quality, using different specific culture media and biochemical tests. Water samples were analyzed within 24 hours of their purchase/collection. Samples were filtered with 0.45 micron and filters were plated in different media. Then media were incubated at 37˚C for 24-48 hours. Morphological study and biochemical tests revealed a number of bacteria in different brands of bottled water. Heterotrophic bacteria(Gram positive cocci, Spore forming gram positive bacilli, non spore forming gram positive bacilli, gram negative bacilli, and gram negative coccobacilli; Pseudomonas and Stenotrophomonas) counted in 70% of bottled water samples. There were no cases of fecal contamination or the presence of E.coli. Bottled water is not sterile and contains trace amounts of bacteria naturally present or introduced during processing. Testing drinking water for all possible pathogens is complex, time-consuming, and expensive. If only total coliform bacteria are detected in drinking water, the source is probably environmental. Since the significance of non-pathogenic heterotrophic bacteria in relation to health and diseases is not understood, there is an urgent need to establish a maximum limit for the heterotrophic count in the bottled mineral water. Growth conditions play a critical role in the recovery of heterotrophic bacteria in bottled drinking water.

Nosocomial infections are defined as infections occurring during a patient's stay at hospital (48-72h after admission).Nosocomial infections are one of the important problems of health. This study aimed was determine the prevalence of nosocomial infections, and related factors in hospitals with more than 100 beds in south Khorasan Province. In this crass-sectional study, an investigator-administered questionnaire was completed for each patient with nosocomial infections diagnosis in hospitals with more than 100 beds in South Khorasan. This questionnaire conation demographic characteristic of patients, department, duration of admission, kind of pathogen and risk factors that was designed according to standard questionnaire of Iranian Nasocomial infections surveillance system (INIS) of Center for communicable Disease Control, Ministry of Health. Data were analyzed with SPSS 16 software. Number of patients with nosocomial infection was 358. The incidence of nosocomial infection was 0.9%. ICU had the highest incidence rate (17.3%). The most common nosocomial infection was pneumonia (43%), and urinary tract infection (UTI) (15.1%). In 33.5% culture result were negative. In other cases, culture results showed klebsiella spp. (12.8%) and Pseudomonas aeruginosa (9.8%) were the most prevalent bacteria. Most factors associated with nosocomial infection in patients were urinary catheters (70.4%), suction (66.8%) and tracheal tube (54.2%). 24% of patients expired. The results showed lower ratio of nosocomial infection, that the main reason is failure to detection and reporting of actual cases of nosocomial infection. Promoting detection and reporting system for Prevention and control of nosocomial infection was recommended