Prevalence of antibiotic resistance in Salmonella Typhimurium isolates originating from Iran: a systematic review and meta-analysis

ObjectiveAntibiotic resistance in Salmonella represents a significant global public health concern. Among various serovars, Salmonella enterica serovar Typhimurium is prevalent in multiple countries. This study aims to conduct a systematic review and meta-analysis to evaluate the pattern of antibiotic resistance in S. Typhimurium isolates from diverse sources in Iran.MethodsWe conducted a comprehensive and systematic search for relevant articles until December 2023 in the following databases: PubMed, Scopus, Web of Science, and SID. The collected data were analyzed using Stata software version 17.ResultsEighteen studies examined the pattern of antibiotic resistance in S. Typhimurium for various antibiotics in Iran. Piperacillin and tetracycline exhibited the highest resistance rates, at 79 and 60% respectively, while cefixime and ceftriaxone had the lowest resistance rates at 0%.ConclusionOur findings indicate a high level of antibiotic resistance among the studied antibiotics. This high level of antibiotic resistance raises concerns and underscores the necessity for monitoring the use of antibiotics. Moreover, resistance to these antibiotics was more prevalent in samples isolated from animals compared to other sources. This highlights the importance of animal screening to detect the presence of drug-resistant isolates, with the ultimate goal of reducing antibiotic resistance and preventing the transmission of resistant strains to humans

Prevalence of Mycobacterium kansasii in clinical and environmental isolates, a systematic review and meta-analysis

BackgroundMycobacterium kansasii infection is one of the most common causes of non-tuberculosis mycobacterial (NTM) disease worldwide. However, accurate information on the global prevalence of this bacterium is lacking. Therefore, this study was conducted to investigate the prevalence of M. kansasii in clinical and environmental isolates.MethodsDatabases, including PubMed, Scopus, and the Web of Science, were utilized to gather articles on the prevalence of M. kansasii in clinical and environmental isolates. The collected data were analyzed using Comprehensive Meta-Analysis software.ResultsA total of 118 and 16 studies met the inclusion criteria and were used to analyze the prevalence of M. kansasii in clinical and environmental isolates, respectively. The prevalence of M. kansasii in NTM and environmental isolates were 9.4 and 5.8%, respectively. Subsequent analysis showed an increasing prevalence of M. kansasii over the years. Additionally, the results indicated a significant difference in the prevalence of this bacteria among different regions.ConclusionThe relatively high prevalence of M. kansasii among NTM isolates suggests the need for further implementation of infection control strategies. It is also important to establish appropriate diagnostic criteria and management guidelines for screening this microorganism in environmental samples in order to prevent its spread, given its high prevalence in environmental isolates

Identification of an intestinal microbiota signature associated with hospitalized patients with diarrhea

As an important global health challenge, diarrhea kills nearly two million people each year. Postinfectious irritable bowel syndrome (IBS) usually manifests itself as the diarrhea-predominant subtype. Small intestinal bacterial overgrowth has been observed more frequently in patients with IBS compared to healthy controls. However, the pathophysiology of IBS is not fully understood, and based on recent evidences, altered gut microbiota is involved in the pathogenesis of IBS. Therefore, we aimed to compare the microbiome in hospitalized patients with diarrhea and healthy individuals. Thirty patients and 10 healthy controls were included into this case–control study. Microbial count was performed using quantitative real-time polymerase chain reaction method using bacterial 16S rRNA gene. Clostridium cluster IV and Bacteroides were significantly more frequent in the patients compared with the healthy individuals (p = 0.02 and 0.023, respectively). However, the quantity of Enterococcus and Bifidobacterium groups were significantly higher in healthy controls than in diarrheal group (p = 0.000076 and 0.001, respectively). The results showed that the number of bacteria in all bacterial groups was significantly different between healthy individuals and diabetic group, whereas the difference between the healthy group and IBS was not significant for Bifidobacterium group. The findings of this study outlined the relationship between diarrhea, IBS, and diabetes disease and bacterial composition. It could be concluded that modifying the bacterial composition by probiotics can be helpful in the control and management of the mentioned disease

Upregulation of pmrA, pmrB, pmrC, phoQ, phoP, and arnT genes contributing to resistance to colistin in superbug Klebsiella pneumoniae isolates from human clinical samples in Tehran, Iran

Background: Antibiotic resistance in Klebsiella pneumoniae isolates, particularly resistance to colistin, has become a growing concern. This study seeks to investigate the upregulation of specific genes (pmrA, pmrB, pmrC, phoQ, phoP, and arnT) that contribute to colistin resistance in K. pneumoniae isolates collected from human clinical samples in Tehran, Iran. Methods: Thirty eight K. pneumoniae isolates were obtained and subjected to antibiotic susceptibility testing, as well as evaluation for phenotypic AmpC and ESBL production according to CLSI guidelines. The investigation of antibiotic resistance genes was conducted using polymerase chain reaction (PCR), whereas the quantification of colistin resistance related genes expressions was performed via Real-Time PCR. Results: The highest and lowest antibiotics resistance were observed for cefotaxime 33 (86.8%) and minocycline 8 (21.1%), respectively. Twenty-four (63.2%) and 31 (81.6%) isolates carried AmpC and ESBLs, respectively. Also, antibiotic resistance genes containing blaNDM, blaIMP, blaVIM, blaSHV, blaTEM, blaCTXM, qnrA, qnrB, qnrS, and aac(6')-Ib were detected in K. pneumoniae isolates. Only 5 (13.1%) isolates were resistant to colistin and the MIC range of these isolates was between 4 and 64 μg ml−1. Upregulation of the pmrA, pmrB, pmrC, phoQ, phoP, and arnT genes was observed in colistin-resistant isolates. The colistin-resistant isolates were found to possess a simultaneous presence of ESBLs, AmpC, fluoroquinolone, aminoglycoside, and carbapenem resistant genes. Conclusions: This study reveals escalating antibiotic resistance in K. pneumoniae, with notable coexistence of various resistance traits, emphasizing the need for vigilant surveillance and innovative interventions

Use of PCR to Detect Mycoplasma hominis and Ureaplasma urealyticum from Semen Samples of Infertile Men who Referred to Royan Institute in 2009

Objective: Infection with genital Mycoplasmas may have harm effects on the reproductivehealth of men, thus leading to male infertility. This study was performed to detectthe prevalence of these bacteria and to study the sperm parameters in infertile men whoreferred to Royan Institute during 2009.Materials and Methods: Semen samples were collected from 220 infertile men and dividedinto three sections. The first section was used for semen analysis, the second sectionfor polymerase chain reaction (PCR) in which U4 and U5 primers were used for theamplification of the urease gene of U. urealyticum, and RNAH1 and RNAH2 primers wereused for amplification of the 16S rRNA gene of M. hominis.Results: From a total of 220 semen samples cultured, 15.5% of M. hominis and 40.5% ofU. urealyticum were isolated. Evaluation of semen parameters showed a lower pH in theU. urealyticum positive group and the group which was positive for both bacteria, ratherthan the group which contained no bacteria (p=0.007 and p=0.000, respectively). Also,the mean sperm motility was lower in the group which was positive for both bacteria whencompared with the U. urealyticum positive group (p=0.009).Conclusion: The results of this study show that a high percent of infertile men are infectedwith these bacteria which may lead to pelvic inflammatory disease (PID) and infertility,thus isolation of these bacteria in infertile couples with no clinical symptoms is necessaryand can be a part of a sexual transmitted disease (STD) control program

A comparison of culture and PCR methods for identification of Aggregatibacter actinomycetemcomitans isolated from acute necrotizing ulcerative gingivitis

Objective: To determine Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) isolated from periodontal patients and healthy subjects using culture and PCR methods. Methods: Duplicate paper point needles were taken from 100 samples (50 healthy subjects and 50 patients), who referred to the specialized dental clinic from Oct. 2015 to Mar. 2016. In laboratory after incubation period and observing the star-shaped colony A. actinomycetemcomitans, the confirmation tests, including gram staining and catalase test were carried out. For PCR, samples were analyzed with genus specific primers. These primers set, amplified a 500 bp fragment. Results: Of the 100 samples, A. actinomycetemcomitans was isolated from 31 patients (31%), (24 isolate of patients, and 7 isolate of healthy subjects) by using a selective Aggregatibacter isolation medium. Using PCR, a total of 49 (49%) samples were found to be positive for A. actinomycetemcomitans (35 isolate of patients, and 14 isolate of healthy subjects). Conclusion: PCR was found to be highly sensitive when genus specific primers were used for diagnosis of A. actinomycetemcomitans in comparison with culture method

Temporary Vision Loss After Spinal Anesthesia

Perioperative visual loss is a rare complication mostly associated with cardiac, spine, and head and neck surgery that could severely affect quality of life. We report a case of temporary visual loss without any other subjective symptom after spinal anesthesia