Avicenna Journal of Clinical Microbiology and Infection
Year:2018 | Volume:5 | Issue:3|Papers Count:6

Background: Staphylococcus aureus is one of the most important pathogens in the development of hospital infections. The production of coagulase is directly related to the pathogenicity of S. aureus. The present study was conducted in order to investigate the polymorphism of the coagulase gene (coa) as a coagulase-encoding gene. Methods: 120 clinical samples were collected from patients admitted to Imam Khomeini and Amiralmomenin hospitals in Zabol, southeastern Iran, during 2014 and screened for the presence of S. aureus. Genetic diversity was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR– RFLP) of coa gene and digested by AluI enzyme. Results: Out of 120 clinical samples, 56 isolates were diagnosed as S. aureus and all of these isolates were positive for the 3′ end of the coa gene by PCR. All isolates produced a single band on coa PCR, with molecular sizes ranging from 600 to 850 bp, with the highest frequency of 700 bp (39%). RFLP analysis of coa gene using AluI revealed P1-P4 band patterns with the highest frequency of P1. Conclusions: The results of this study showed that P1 pattern was the most frequent pattern and lowest frequency was observed in P4 pattern. The results of this study suggest that the RFLP of coa gene can be used as a fairly suitable method for determining the genetic differences between S. aureus isolates.

Background: Drug interactions (DIs) are one of the problems caused by irrational drug use and includes the effects of drug, food, or anything that changes the pharmacokinetics or pharmacodynamics of a given drug. In this regard, DI is one of the causes of morbidity and mortality in patients. However, this problem is usually predictable and hence is required to be properly managed. The aim of the present study was to assess DIs in the patients hospitalized in the intensive care units and infectious ward of Sina hospital, Hamadan, Iran. Methods: This cross-sectional study was conducted on the medical records of 500 patients hospitalized in ICUs and infectious ward of Sina hospital in Hamadan from March 2014 to February 2015. The inclusion criterion was the presence of at least one DI in the patients hospitalized in the intensive care units (ICUs) and infectious ward of the hospital for at least 24 hours. The potential DIs were classified based on the type and severity. Medical and demographic characteristics of the patients, including age, sex, duration of hospitalization, inpatient ward, and treatment results (death or advances in treatment) were collected using a checklist. Data were analyzed using SPSS software version 16. 0. Results: A total of 514 DIs were identified from which 5. 05% were major and 41. 82% were moderate interactions. The mean of DI per patient was 2. 81 in the range of 1 and 23. The frequency of antibiotic/ antibiotic and antibiotic/other drugs interactions were 7. 97% and 28. 98%, respectively. The average length of stay in hospital was 12. 07 days, and 26. 22% and 25. 13% of the studied patients were hospitalized in general and infectious ICUs, respectively. The mean of DIs per patient was significantly higher in infectious ICU rather than other studied wards. Conclusions: To sum up, although the percentage of major DIs were low, the prevalence of total DIs was high in the studied patients. Based on the results of this study, it seems that physicians must be aware of the presence of potential and harmful DIs. Moreover, working under the careful supervision of a clinical pharmacist in hospitals and continuous training around DIs and training the pharmacological care to physicians can be effective in the prevention of DIs.

Background: Linguatula serrata is a worm-like parasite which is usually well-known as the tongue worm and aberrant cosmopolitan zoonotic arthropod placed in the order Pentastomida. The carnivorous mammals, especially cats and dogs, are known as the final hosts of this parasite, and the adult step happens in the nasal sinuses and nasopharynx, while nymphal steps in ruminants as the main intermediate hosts can progress in several organs, mainly mesenteric and mediastinal lymph nodes. The aim of this study was to evaluate the prevalence of L. serrata nymphs in goats slaughtered in Mashhad slaughterhouse, Iran. Methods: The prevalence of L. serrata nymphs in mediastinal and mesenteric lymph nodes (MLNs) of 400 slaughtered goats from different sexes and age groups were examined. To this end, the MLNs were longitudinally cut and microscopically evaluated for L. serrata nymphs. The goats were slaughtered in Mashhad slaughterhouse, Iran. The data were analyzed using SPSS software (version 16. 0) and chi-square test was used for determining the significance of the differences. The P values less than 0. 05 were considered statistically significant. Results: As revealed by the results, the prevalence rate was 19%. The age had a noteworthy effect on the frequency rate of the mentioned parasite in the goats as was seen in 3-year old goats. A significant difference was observed in the infection frequency in two genera of male and female (P < 0. 05). Conclusions: Based on the results and zoonotic nature of studied parasite, preventive procedures should be considered to reduce the risk of transmission.

Background: A growing number of resistant Pseudomonas aeruginosa isolates have been reported. To make better choice of antibiotic, reporting and analyzing the recent antibiotic resistance patterns of the bacterium are of crucial importance. The purpose of the present study was to survey antibiotic resistance status in clinical isolates of P. aeruginosa and to make more options for antibiotic prescription by revisiting antibiogram results. Methods: A total of 138 molecularly identified P. aeruginosa strains isolated from clinical specimens were tested for sensitivity to 10 antibiotics using Kirby-Bauer disk diffusion method. In addition, phenotypic combined disk diffusion test (CDDT) was applied to screen metallo-beta-lactamase (MBL) producing P. aeruginosa isolates among imipenem-resistant isolates. To find the most suitable antibiotic against P. aeruginosa infections, a new analytical way was employed using SPSS and chi-square test. Results: Ceftizoxime showed the highest rate of resistance (78. 9%) and amikacin showed the lowest (33. 3%). 51. 4% of the isolates showed resistance to Imipenem, 78. 8% of which were positive for MBL production. Multidrug-resistant strain (MDR) isolates were observed in 67. 3% of all isolates, 74. 6% of Imipenem resistant isolates showed multidrug resistance and 83. 9% of MBL positive isolates showed MDR. There was positive correlation between specimen source and resistance or susceptibly of P. aeruginosa isolates to some antibiotics in some specimens, and non-significant similarities in resistance or sensitivity to antibiotics in P. aeruginosa isolates (P < 0. 05). Conclusions: Resistance rate of imipenem, meropenem, gentamicin, tobramycin, ceftazidim, cefotaxime and ticarcillin was more than reported rates in previous studies. A higher proportion of MDR isolates and MDR-MBL producing strains suggest drastic dissemination of resistant isolates in the healthcare centers. Site specificity and non-significant similarity of the responses to antibiotics in P. aeruginosa isolates can provide a new sight for antibiotic prescription and better control of antimicrobial drug resistance.

Background: Acinetobacter baumannii is one of the most common causes of nosocomial infections. The knowledge about resistance and susceptibility of this bacterium to antibiotics is mandatory in every region. This study evaluated the susceptibility of A. baumannii strains to ampicillin-sulbactam and colistin in a total of 100 samples of A. baumannii obtained from intensive care unit (ICU) patients with nosocomial infections. Methods: After identification of A. baumannii, susceptibility to ampicillin-sulbactam and colistin was assessed using Epsilometer test (E-test). Results: Regarding the resistance to ampicillin-sulbactam, sensitivity, resistance, and intermediate resistance of A. baumannii strains were 62%, 16%, and 22%, respectively. The distribution of resistance among A. baumannii strains was not significantly different regarding the gender, age, duration of ICU stay, background diseases, and type of interventional procedure. The obtained strains of A. baumannii from the patients who had taken β-lactam, aminoglycoside, anti-methicillin resistant Staphylococcus aureus (anti-MRSA), and colistin were significantly resistant to ampicillin-sulbactam (P value <0. 05). Overall, 16% of Conclusion: Acinetobacter baumannii strains showed resistance to ampicillin-sulbactam and only one strain was detected with colistin resistance. It is suggested that a local antibiotic resistance regarding A. baumannii infection be defined in order to improve final outcome of antimicrobial treatment and prevent further resistance.

Background: Staphylococcus aureus is a gram positive pathogen which causes a wide range of infections. The present study aimed to investigate genotypic and phenotypic screening about biofilm formation in S. aureus isolated from wound infections in a diabetes clinic in Hazrat Fatemeh Zahra (SA) hospital. Methods: A total of 267 clinical samples were collected from various types of wound infections in the diabetes clinic of Hazrat Fatemeh Zahra (SA) hospital, Isfahan, Iran. The methicillin-resistant S. aureus (MRSA) isolates were selected and biofilm formation and its related genes were analyzed by polymerase chain reaction (PCR). Results: The results showed that 95 out of 132 samples were MRSA. The high resistance was seen to methicillin, erythromycin, ciprofloxacin, and penicillin. Phenotypic results showed that 48. 3% of the isolates were high biofilm producers, 29. 1% were average biofilm producers, and 10. 6% were low biofilm producers. Conclusions: According to the results of this study, the expression levels of biofilm-associated genes significantly increased, and high prevalence of antibiotic resistance was one of the important reasons for the development of drug resistance in patients.