Jundishapur Journal of Microbiology
Volume:13 Issue: 7, Jul 2020

Context: 

Group B Streptococcus has the capacity of being colonized in the rectovaginal organ of women and causes infections in a mother and her fetus, thereby leading to neonatal diseases.

Evidence Acquisition: 

The aim of this review was to summarize all of the relevant articles published to highlight the prevalence of group B Streptococcus colonization or infection in different regions of Iran. A systematic literature review was conducted by searching PubMed, Scopus, Web of Science (ISI), ScienceDirect, Google Scholar, and domestic databases for papers published in English or Persian from 1992 up to July 2019, concerning the prevalence of group B Streptococcus among Iranian women. All information regarding year, location of cases, frequency, author’s name, date of publication, participants, pregnancy period, sampling, and quality assessment were recorded. Summary effects were derived using the random effects model.

 Among 61 suitable papers, data revealed that 36,807 cases of pregnant and non-pregnant women had been tested for group B Streptococcus during 1992-2018. Overall, 11.9% of pregnant and 5.3% of non-pregnant women were positive. Further results were as follows: vaginal, recto-vaginal, rectal, and endocervical colonization rates were 12.9%, 9.7%, 18.5%, and 3.7%, respectively. Group B Streptococcus incidence was the highest in Sanandaj (61.5%), and the lowest in Tabriz (1.8%).

 Although the prevalence distribution in Iran seems to be acceptable, more investigations are needed to represent the real incidence of group B Streptococcus around the country. In addition, a program with a standard lab technique is needed to screen pregnant women for further treatment before birth.

 Infections caused by Staphylococcus aureus strains are a major public health challenge worldwide, especially in specialized burn hospitals. Infections caused by S. aureus account for more than 50% of burn-related deaths.

 Since data on characteristics of these isolates are not sufficient, the current study aimed to assess the prevalence of resistance to antibacterial agents and to analyze the distribution of biofilm, and adhesion encoding genes among S. aureus strains isolated from burn patients in Motahari Hospital, Tehran, Iran.

 A total of 83 S. aureus strains were collected from burn wounds of patients admitted to a referral burn center in Tehran for 10 months. In vitro antibacterial susceptibility of isolates was evaluated using the Kirby-Bauer disk diffusion method. Strains were subjected to polymerase chain reaction (PCR) to determine the presence of nucA, mecA, ebps, cna, bbp, fnbA, fnbB, clfA, and clfB genes.

 The highest frequency of resistance was found to cephalexin and cefoxitin (87.9%), followed by clindamycin (75.9%), erythromycin (72.3%), and ciprofloxacin (60.2%). Five resistance patterns were identified in which cephalexin, cefoxitin, clindamycin, erythromycin, and ciprofloxacin had the most predominant resistance profile (36.1%). Biofilm gene detection indicated a markedly high prevalence of cna (74.7%), clfB (54.2%), clfA (50.6%), fnbA (42.1%), ebp (13.2%), and fnbB (12%). Six different biofilm genetic patterns were identified, wherein clfA, clfB, fnbA, ebp, and cna (30.1%), clfA, clfB, fnbA, fnbB, ebp, and cna (12%), and clfA, clfB, and cna (8.4%) were the top three most frequently identified patterns.

 The prevalence of biofilm encoding genes, which are associated with multidrug resistance in S. aureus strains isolated from burn patients, is high. Therefore, identification of epidemiology, molecular characteristics, and biofilm management of S. aureus infection in burn units would be helpful.

 Enteropathogenic Escherichia coli (EPEC) is one of the most important pathogens among young children worldwide. Both eae and bfp genes have been used to identify EPEC strains and categorize them into typical and atypical strains. They may be an emerging pathogen in both developing and developed countries.

 This study was primarily conducted to assess the epidemiology, drug resistance, and β-lactamase distribution of EPEC, as well as the detection of efa1/lifA in atypical strains.

 A total of 251 E. coli strains isolated from children with diarrhea were evaluated for their EPEC pathotype by PCR for the presence of eae, stx1, stx2, and bfp genes. Serogrouping with polyvalent antisera was performed to confirm EPEC strains. Atypical EPEC-containing samples were evaluated for the efa1/lifA gene. EPEC isolates were assessed to recognize the antibiotic resistance and screened to detect extended-spectrum β-lactamases (ESBLs).

 Enteropathogenic E. coli strains were detected in 17 (6.78%) of E. coli isolates by PCR. The prevalence of typical and atypical strains was determined at 35.3% and 64.7%. All strains were completely susceptible to colistin, imipenem, and meropenem. The prevalence of blaCTX-M and blaTEM genes was calculated at 70.58% and 58.82%, respectively.

 Enteropathogenic E. coli isolates are completely sensitive to carbapenems, and precise therapeutic strategies are required to prevent the spread of these beta-lactamase genes among diarrheagenic E. coli.

 Gastric cancer is one of the main causes of death worldwide. In this regard, Helicobacter pylori infection is considered as the main risk factor for gastric cancer. MicroRNA (mirNA) can interface with mRNA molecules as well as blocking their translation into proteins or inducing degradation.

 The aim of this study was to compare the expression of mir-21 in biopsy samples of gastritis and healthy adjacent tissues.

 Between Feb-Dec 2017, 70 patients with dyspeptic symptoms from Taleghani Hospital were enrolled in this study. Accordingly, the expression level of mir-21 was evaluated using semi-quantitative RT-PCR in mucosal biopsy samples from those well-characterized patients. Moreover, the U6 gene was used as an internal control.

 Our data indicated that mir-21 expression was significantly up-regulated in the infected samples with H. pylori compared to healthy samples.

 Our results confirm that H. pylori infection can alter the expression of mir-21 in gastric epithelial cells and gastric mucosal tissues. However, the exact role of the miRNA changes in H. pylori infection will require further experiments.

 Gastric cancer has been introduced as the second cause of cancer death worldwide. Helicobacter pylori infection is considered one of the main risk factors for this type of cancer, so that it has been classified as group I carcinogens.

 The present research intended to examine the prevalence of cagA, cagC, virB2, vacA, and genotype distribution in H. pylori-infected biopsies and adenocarcinoma cases.

 Thirty-four H. pylori gastric biopsies taken from Western Iranian patients that were diagnosed as gastritis, gastric ulcers, and adenocarcinoma were used in this study. Two samples were taken from each patient. These samples were selected based on endoscopic observations and histological examinations. The presence of H. pylori was confirmed by the Rapid Urease test (RUT) and the ureC gene by the polymerase chain reaction (PCR) technique. Then, specific primers for vacA and cagPAI were used for genotyping H. pylori by PCR-typing.

 The obtained results showed that 86.8% of the samples were H. pylori-positive. Moreover, the cagA gene prevalence was 51.50% in the samples. In addition, the adenocarcinoma outcome was significantly related to all selected genes. Likewise, some gastric diseases such as gastric ulcers, duodenal ulcer (DU), gastritis, lymphoid, and gastroesophageal reflux disease (GERD) were observed in adenocarcinoma cases. It was also found that the vacAs1m1i1 genotype plays an important role in gastric malignancies. The most frequent vacA genotype in the H. pylori-infected isolates was s1m1i1, and the observed frequency of vacA and cagA genes in adenocarcinoma was statistically significant.

 The findings showed that H. pylori vacA and cagA gene virulence factors are associated with adenocarcinoma in Western Iranian patients.

 Assessment of bacteria such as Klebsiella pneumonia has shown that Plasmid-mediated quinolone resistance (PMQR) affects antibiotics resistance (e.g., quinolones).

 We studied the prevalence of qnr and aac(6’)Ib-cr genes in extended-spectrum beta-lactamase (ESBL)-producing K. pneumonia strains isolated from burn wounds of patients in the city of Kermanshah, Iran.

 This descriptive-analytical study was conducted on 126 K. pneumonia strains isolated collected from burn wounds. Biochemical tests were used to detect the strains. The frequency of the ESBL-producing isolates was determined by phenotypic tests of the combination disk (CD) method after determining the antibiotic susceptibility pattern of the isolates through the Kirby-Bauer disc diffusion test. The prevalence of the qnr and aac(6’)-Ib-cr genes was determined using their special primers as well as polymerase chain reaction (PCR).

 Of the 126 K. pneumonia isolates, 52 (41.3%) were identified as ESBL-producing strains. ESBL-producing isolates showed higher resistance against antibiotics than non-ESBL-producing ones. PMQR relevance and resistance to ciprofloxacin were, respectively, determined at 80.76% and 59.6%. The most frequent gene was aac(6’)-Ib-cr (n = 70, 55.6%), followed by the qnrB (n = 44, 34.9%).

 This study showed a high prevalence of qnr genes in ESBL-producing K. pneumonia isolates and antibiotic resistance. Given the horizontal transmission of antibiotic resistance genes among bacteria by mobile genetic elements, timely identification of infections caused by ESBL-producing and antimicrobial-resistant K. pneumonia strains is of paramount importance.

 Traditional antibiotics are no longer as effective as before for controlling pathogens associated with urinary tract infections (UTI), which shows the necessity of developing new and more effective antibiotics.

 The current study aimed to evaluate in vitro susceptibility of fosfomycin and tigecycline towards common antibiotic-resistant Gram-negative bacilli isolated from the urinary tract. Besides, clinico-microbiological on fosfomycin and tigecycline resistant Gram-negative bacilli was investigated.

 In this descriptive cross-sectional study, 150 resistant Gram-negative bacilli were isolated from urine specimens send for culture, and antibiotic susceptibility assessment to the Division of Microbiology of Sina Hospital affiliated to Tabriz University of Medical Sciences which were collected from April-September 2017 are included. Antibiotic susceptibilities were evaluated according to the Clinical and Laboratory Standards published by the Institute and the criteria of the Food and Drug Administration.

 Of 150 isolates, 138 (92%) were susceptible, and 2 (1.3%) were resistant to both fosfomycin and tigecycline, as confirmed by disk diffusion and Epsilonmeter tests. The difference was statistically significant (P = 0.001).

 Based on the results, resistance to the conventional antibiotics prescribed for the treatment of UTI was significantly high. Fosfomycin and tigecycline have an appropriate antimicrobial activity towards Gram-negative-resistant isolates involved in UTIs.

 Rotavirus infection is still the leading cause of acute viral gastroenteritis in children under five years of age worldwide. It is also a serious public health concern in China.

 This study aimed to obtain information about rotavirus diarrhea among hospitalized children in Hefei City, Anhui Province, China, in recent years.

 We conducted a retrospective study over four years (2015 - 2018) examining hospital admission records of rotavirus infections at the First Affiliated Hospital of Anhui Medical University in Hefei City of Anhui Province, China.

 A total of 1,095 cases with acute viral gastroenteritis requiring hospital admission from January 2015 to December 2018 were analyzed. Among them, 276 cases were positive for rotavirus A infection, accounting for 25.21% of the total number of children suffering from acute diarrhea. The detection rate of rotavirus A was the highest in children aged 1 - 2 years. The peak month for rotavirus infection during 2015 - 2018 was December and January. The hospitalized children with rotavirus infection showed dehydration, electrolyte disorder, liver function abnormality, and myocardial enzyme abnormality.

 Rotavirus is still the first pathogen of acute viral diarrhea in children in Hefei, especially children < 2 years of age, which highlights the need for widespread rotavirus immunization in young children.