Avicenna Journal of Clinical Microbiology and Infection
Year:2018 | Volume:5 | Issue:2|Papers Count:7

Background: Inflammation or infection of the ear that refers to as otitis is a common ear disorder. The otitis externa infection involves outer ear and ear canal. Streptococcus pyogenes, Staphylococcus aureus, and Pseudomonas aeruginosa can be pointed out as the common causative agents of this infection. Due to the detrimental effects of chemical drugs on humans, utilizing the new formulation of herbal essential oils, such as nano-encapsulation is considered owing to the more efficient and reduction of adverse effects resulting from the direct application of essential oils. In this in vitro study, the antimicrobial effects of 4 nano-essences were compared to pure essential oils against four major microorganisms involved in otitis externa (namely, S. pyogenes, S. aureus and P. aeruginosa).Methods: To evaluate the antibacterial effects of nano-essences, minimum inhibitory concentration (MIC) quantitative determination and minimum bactericidal concentration (MBC) were first carried out, and then qualitative disk diffusion tests were conducted.Results: The MIC quantitative test results demonstrated that among the evaluated essential oils, garlic nano-essence had the most antimicrobial effect at the lowest concentration. Besides, the results showed that nano-essences had lower effect compared to pure essential oils. Diffusion disc test results revealed that nano-essences could not be released from paper discs diffusion in solid media.Conclusions: Results suggested great antibacterial effects of nano-essences of garlic, thyme, peppermint, and chamomile on 3 strains of bacteria involved in otitis externa and it can be promised to produce new drugs, with lower side effects in eliminating these pathogens.

Background: Probiotics are non-pathogenic useful microorganisms having positive effects on the host health. The aim of the present study was to discriminate Lactobacillus species extracted from traditional dairy products.Methods: This study was conducted on 26 specimens collected from traditional dairy products in Bukan. Lactobacillus species were separated and purified employing biochemical tests. Then, the intra/inter-species diversity was investigated using RAPD-PCR (random amplified polymorphic DNA-polymerase chain reaction) technique.Results: Polymorphism information content (PIC) value varied between 15.9% and 34.4% with a maximum value of 34.4% associated with primer 1254. The mean of and Marker index (MI) for the 6 primers was 4.52, in which the maximum and minimum values belonged to the primers 1254 and OPA-02, respectively. The isolates were categorized into 4 main clusters according to Jaccard similarity coefficient using UPGMA (unweighted pair group method with arithmetic means) clustering method. Principle coordinates analysis (PCoA) demonstrated that the first and second components explained 30.59% and 22.48% of variances, i.e.53.07% of variances in total. The results of RAPD marker indicated that the intra-species diversity was greater than inter-species diversity. The intra-group variance explained 94% of the all variance, while inter-group variance explained only 6% of the all variance. Moreover, the results of analysis of molecular variance (AMOVA) indicated that the highest level of discrimination occurred at the 16 groups cut-off point with a similar coefficient of 0.56.Conclusions: From the results of the present study, it can be concluded that traditional dairy products are enriched sources of probiotic bacteria which can ensure the health of general population and enhance their immunoe systems. Moreover, RAPD-PCR is an appropriate method for detection and calssification of lactobassiluses.

Background: Cystic echinococcosis (CE) also known as hydatid disease, is a zoonotic helminthic disease caused by infection with the larval stage of a tapeworm Echinococcus granulosus. It is an important parasite regarding human health and is categorized into different genotypes. The present study aimed to identify different genotypes of E. granulosus metacestode isolated from Iranian camel.Methods: In this cross-sectional study, 54 hydatid cysts were isolated from slaughtered Iranian camels (Camelus dromedarius) in Isfahan (33 samples) and Yazd (21 samples) province s’ laughterhouses. The DNA was extracted from the isolated hydatid cysts and high resolution melting analysis (HRM) was performed. The curves were confirmed by sequencing and aligning with previously deposited sequences.Results: Based on the results of the present study, 94.4%, 3.7%, and 1.9% of the studied isolates were identified as E. granulosus (G1), E. granulosus (G2), and E. intermedius (G6) in the two studied regions, respectively. Moreover, 85.18% of the cysts were isolated from lung and 5.82% of them were also isolated from the liver of the camels.Conclusion: Based on the HRM analysis of cox1 and atp6 genes, E. granulosus (G1) accounts for the most cases of camelid cystic echinococcosis, and demonstrates camels as a source of human cystic echinococcosis.

Background: The bacterial strains which cause symptomatic urinary tract infections possess diverse distinctive properties that enable them to overcome local host defences. The present study was undertaken to screen for the virulence factors of uropathogenic Escherichia coli (UPFC) by molecular methods and to detect the genotypic pathogenicity related sequences pap, sfa, and afa genes in E. coli strains by polymerase chain reaction (PCR).Methods: A total of 350 E.coli isolates were obtained from symptomatic cases of urinary tract infections (UTI) and 60 E. coli faecal isolates were collected from apparently healthy individuals (during February 2014-2016) from outpatient department of a tertiary care hospital in Kerala, India. Isolates were tested for adhesive genes pap, sfa, and afa.Results: Among the UPEC samples, 255 (72.85%) of the isolates were from females and 95 (27.14%) of them were obtained from males. The prevalence of pap gene was seen in 72 of the total isolates which were the highest. The sfa genes were shown by 56 isolates. The afa genes were also in 7 of the isolates. Diversity of the UPEC associated virulence genes were established in this study.Conclusions: The E.coli causing UTI had greater percentage of virulence associated adhesin genes compared to E.coli from control stool samples.

Background: Urinary tract infections (UTIs) are very common worldwide. Such an infection is usually treated with empirical antimicrobial therapy. However, there are trends of increasing rates of antibiotic resistance. The aims of this study were to determine the most common bacterial causative agents and their antibiotic sensitivity pattern in women suffering from UTI in Duhok, Kurdistan, northern Iraq.Methods: Urine samples were collected from 371 subjects afflicted with UTI and inoculated directly on blood and MacConkey agar and then incubated at 37°C for 24 hours. Bacterial colonies were determined by standard culture and biochemical characteristics. All isolates were tested for their antibiotic susceptibility.Results: The vast majority of the isolates were Gram-negative and only 2 (0.5%) of them were Gram-positive. The highest infection by Gram-negative bacteria belonged to Escherichia coli 276.371 (74.4%) and about 74.2% of which were resistant to amoxicillin/clavulanic acid. Additionally, around 65% of the isolated E. coli were resistant to ceftriaxone, ceftazidime, and cefepime. It was found that the Pseudomonas strains were resistant to ceftazidime (42%), ertapenem (75%), and ciprofloxacin (50%).Conclusions: There were increasing rates of antibiotic resistance especially in E. coli. Urgent measures are needed to contain such a resistance pattern and a plan for continuous surveillance is required to monitor antibiotic sensitivity pattern.

Background: The nosocomial infections are the ones that arise between 48 to 72 hours after patient’s reference to hospital, shortly after hospital discharge, or 30 days after an operation. This study aimed to evaluate the prevalence of nosocomial infection in different wards of Be’sat hospital of Hamedan.Methods: This prospective cross-sectional study was conducted (during April-July 2016) on admitted patients that suffered from nosocomial infections based on CDC (Centers for Disease Control and Prevention) criteria. During the time of the study, patients who referred to different wards of the hospital (except for the pediatric ward), showed clinical signs of nosocomial infection 48 hours after the admission. Their tracheal, urine, blood, and surgical wound samples were transferred to laboratory for culture and identification of infectious agent. Patients’ demographic information were encoded as confidential records, then, the data were analyzed using SPSS software. All ethical principles of the Helsinki Declaration were observed.Results: Out of a total of 10332 hospitalized patients, 266 (2.6%) of them acquired nosocomial infection of which 183 (69%) of them were males and 83 (31%) were females. The patients’ mean age was 58.14. There was no significant relationship between the age and the type of nosocomial infections (P=0.052). The mean period of hospitalization was 28.2 days. The most common nosocomial infection was ventilator associated pneumonia (VAP) with 110 cases (41.3%) and the rarest of them was catheter associated-urine tract infection (CA-UTI) with 23 (8.64%) cases. Fifty-nine cases (53.6%) out of 110 VAP patient cases survived and 51 (46.4%) of them died. The overall mortality rate was 30%. Among 242 bacterial strains isolated, Escherichia coli was the most common strain with a prevalence of 61 (22.9%). Most of the death cases (57.9%) were caused by Proteus nosocomial infections.Conclusion: The high values of nosocomial infections and mortality in Be’sat hospital represent a need to reinforce the preventive and control program on nosocomial infections. In future studies, in order for better presentation of nosocomial infection in terms of latest events, infection and organism type, and antibiotic resistance pattern, novel indexes like device utilization ratio (DUR) and incidence density of device-associated infections (IDDI) are suggested.

Background: Pseudomonas aeruginosa is a common opportunistic pathogen that causes nosocomial infection in immunocompromised patients. Among different virulence factors, the type III secretion system (TTSS) is an important agent in virulence and development of antimicrobial resistance in P. aeruginosa. Previous studies have shown that production of TTSS proteins was correlated with increasing virulence and resistance to several antibiotics. In this study, the exotoxins genes (exoU and exoS) and pattern of antimicrobial susceptibility in clinical P. aeruginosa isolates were determined.Methods: A total of 175 P. aeruginosa isolates were collected from patients hospitalized in Shahrekord and Chamran educational hospitals of Isfahan, Iran (during April to December 2015). Antimicrobial susceptibility test was performed by disk diffusion test. The presence of exotoxin genes was detected using multiplex polymerase chain reaction (PCR) of exoU and exoS genes.Results: The antibiotic resistance rate was higher than 70% to many antibiotics. The highest rates of resistance (155 and 148) were related to Levofloxacin (88.6%) and Meropenem (84.6%), respectively. The exoU gene was found in 75 (42.9%) isolates and 136 (77.7%) isolates carried the exoS. In addition, 36 (20.6%) of the isolates carried both genes. A statistical significance was observed between the presence of exoU gene and resistance to piperacillin (P=0.01).Conclusions: The result of this study showed a high resistance rate to the most antibiotic classes and a specific relationship between the virulence genotype and antimicrobial resistance especially more virulent genotype of exoU+. In order to prevent the spread of more virulent strains in health care facilities, molecular methods alongside antimicrobial susceptibility tests are suggested.