Jundishapur Journal of Microbiology
Volume:16 Issue: 3, Mar 2023

Acinetobacter baumannii is one of the most important known causes of hospital infections worldwide that is resistant to many common antibiotics. Efflux pumps are among the main reasons behind resistance in this bacterium.

This study was conducted to investigate the presence of efflux pump genes (adeI, adeJ) in clinical antibiotic-resistant isolates of A. baumannii in Tehran hospitals.

One hundred fifty clinical samples of wounds, urine, sputum, and blood were collected periodically (6 months) from Tehran hospitals. A. baumannii was identified using common biochemical methods. After conducting biochemical tests, the final confirmation of the samples was performed by examining the blaOXA-51-like gene by molecular polymerase chain reaction (PCR) method. The disk diffusion antimicrobial susceptibility testing was performed using Mueller Hinton agar growth medium according to Clinical and Laboratory Standards Institute (CLSI) guidelines on nine antibiotics. Then the samples were investigated for the presence of adeI and adeJ genes.

Examining the antibiotic resistance of the isolatesshowedthat the resistance level variedfrom48.1% to 98.2%, dependingon the antibiotic type. In this study, isolates showed the highest and lowest resistance to tetracycline and gentamicin, respectively. Also, positive isolates for the presence of adeI and adeJ genes showed the highest resistance to tetracycline, amikamycin, ceftazidime, and ceftriaxone. Isolates that were negative for the presence of these two genes showed the highest sensitivity to imipenem, gentamicin, and ciprofloxacin.

In this study, the correlation of antibiotic resistance test and PCR results showed that the presence of adeI and adeJ genes in the samples significantly increased the resistance to all investigated antibiotics. Therefore, evaluating efflux pumps proves to be useful in identifying antibiotic-resistant strains and appropriate drug treatment. Of course, the role of other factors in creating resistance should not be neglected.

The frequency of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli strains among clinical isolates has been steadily increasing, leading to limited treatment options.

This study aimed to assess the antibiotic sensitivity of E. coli and the frequency of ESBL isolates among both out-patients and in-patients.

A total of 390 E. coli isolates were received at the Ali-Ebn-e-Abitaleb Hospital laboratory in Rafsanjan. The antibiogram, as well as the phenotypic and genotypic detection of ESBL isolates, were conducted using Kirby-Bauer, combination disk confirmatory, and polymerase chain reaction tests, respectively.

Of all the E. coli isolates, 45.6% exhibited ESBL production. Among these isolates, 46.1% were obtained from hospital wards, while 42.5% were from outpatients. Meropenem and imipenem displayed sensitivities of 97.2% and 93.3%, respectively, whereas amikacin and nitrofurantoin showed sensitivities of 89.7% and 85.6%, respectively, for all isolates. Notably, ceftriaxone, cefotaxime, cefixime, ampicillin, co-trimoxazole, andnalidixic acid demonstrated high resistance rates, surpassing 50%. ESBL-producing isolates were more frequently observed in blood samples (65%) and wounds (60%) compared to other tested isolates. Approximately 8.6% of isolates carried a single type of ESBL gene, while 38.5% carried multiple ESBL genes.

The data indicate a prevalence of ESBL-producing E. coli isolates among both out-patients and in-patients, with some of them acquiring two or three types of ESBL enzymes. As a result, their ability to hydrolyze antibiotics has increased, leading to their higher occurrence in clinical samples.

Serological studies can demonstrate pathogen circulation in regional populations and reflect public health measures’ effectiveness during different pandemic phases. By late November 2021, coinciding with the third pandemic wave, the seroprevalence of SARS-CoV-2 spike IgG antibodies among the Iranian population was 32.63%.

This study aimed to assess the Iranian population’s seroprevalence during the fifth pandemic wave by analyzing donated blood samples.

This population-based cross-sectional study was conducted on Iranian blood donors referred to all 31 main provincial capitals between August 2021 and September 2021. The participants selected through quota sampling were asked to complete a questionnaire on socio-demographics and coronavirus disease 2019 (COVID-19)-related information. Also, SARS-CoV-2 spike IgG antibodies were measured in serum samples using SARS-CoV-2 enzyme-linked immunosorbent assay (ELISA) kits. The seroprevalence was weighted based on the gender and age groups of the population and then adjusted for test performance.

Totally 3,339 blood donors participated in this study. The overall population-weighted seroprevalence adjusted for test performance was 52.67% (95% confidence interval (CI): 50.14 - 55.21). Seroprevalence was higher among participants with a high school diploma (55.45%, 95% CI 50.61 - 60.29), a positive history of close contact with COVID-19 patients (65.23%, 95% CI 60.83 - 69.63), and previous positive COVID-19 PCR tests (86.51%, 95% CI 82.32 - 90.7).

More than half of the study population was exposed to SARS-CoV-2, indicating a 1.7-fold increase in the seroprevalence between late November 2020 and mid-September 2021. Our finding illuminated the pattern of Iran’s fifth wave of the pandemic.

COVID-19 infection is a contemporary global concern with serious ramifications. This disease is caused by a virus belonging to the Coronaviridae family named SARS-CoV-2. Immunologic and physiologic changes during pregnancy make pregnant women more susceptible to viral infection, especially COVID-19.

The present study aimed to identify the clinical manifestations, radiologic findings, indications for cesarean delivery, underlying conditions, and the critical outcome of mothers and newborns regarding COVID-19 women who had cesarean sections and terminated pregnancies.

This cross-sectional study was conducted on the mortality and morbidity rates of 98womenwith terminated pregnancies infected with COVID-19 at the time of their cesarean delivery. The demographic, clinical, and pregnancy data were collected from Razi Teaching Hospital between March 2020 and March 2021 and analyzed using SPSS version 24.

The mean age was 31.31 ± 7.16, and the mean gestational age was 36.45 ± 3.334 weeks. The most prevalent cause of cesarean section was fetal distress (28%), followed by preeclampsia andmeconium aspiration. The mostcommonsymptoms were sore throat, cough, fever, nausea, diarrhea, and weakness; moreover, hypothyroidism and diabetes mellitus were the most predominant underlying diseases. The mean duration for hospitalization was 5.21 ± 4.584 days, the maternal death rate was 5.1%, and the neonatal death rate was 2%.

The majority of women infected with COVID-19 had cesarean sections and terminated pregnancies in the third trimester. This highlights the need for better care and education for mothers in this period. The body mass index (BMI) level and obesity are strongly associated with COVID-19 severity. Furthermore, healthcare workers should pay more attention to underlying diseases during pregnancy.

 Multi-drug resistant (MDR) and extensively drug-resistant (XDR) Pseudomonas aeruginosa isolates are of clinical concern.

 To determine the distribution of antiseptic resistance genes and the associated level of phenotypic antiseptic resistance against quaternary ammonium compounds and biguanide compounds, we studied MDR and XDR P. aeruginosa isolates collected from different infections among patients from a single hospital.

 Pseudomonas aeruginosa isolates were investigated in 2020 for in vitro susceptibility to benzethonium chloride (BTC), benzalkonium chloride (BKC), and chlorhexidine digluconate (CHG). The minimum inhibitory concentrations (MICs) against these antiseptic agents were determined using broth microdilution. Also, polymerase chain reaction (PCR)-mediated detection of qacE, qacEΔ1, and blaOXA-23 genes was used.

 Isolates were largely non-clonal according to their phenotypical and genotypical non-similarity (35 overall data-combination types detected). Most P. aeruginosa infections occurred in intensive care unit (ICU) patients (n = 43, 61.4%). Extensively drug-resistant and MDR phenotypes were detected in 20% and 12.6%, respectively. Among the 70 isolates retained, 53 (75.7%) harbored at least one resistance gene, comprising 11 (20.7%) isolates with solely the qacEΔ1 gene; seven (13.2%) isolates harbored the qacE gene. Both the qacE and qacEΔ1 genes were detected simultaneously in 35 (66%) isolates. The mean MICs for BTC (24.0 versus 10.56 µg/mL), BKC (46.1 versus 17.22 µg/mL), and CHG (107.7 versus 29.4 µg/mL) were statistically significantly higher among antiseptic resistance gene harboring isolates than in other isolates without such genes.

 The significantly increased MICs against antiseptic agents among antibiotic-resistant P. aeruginosa isolates highlight the importance of monitoring such increases and implementing effective infection control.

 Carbapenem-resistant Pseudomonas aeruginosa is an endemic problem in several countries, notably Turkey.

 This study aimed to investigate the underlying mechanisms contributing to the carbapenem resistance phenotype and enhance the in-vitro activity of ceftolozane-tazobactam (C/T) and ceftazidime-avibactam (C/A) against carbapenem-resistant P. aeruginosa strains.

 A total of 114 carbapenem-resistant P. aeruginosa strains were isolated from different types of clinical specimens. The tested antibiotics were evaluated using the antibiotic disk diffusion method. Additionally, C/T and C/A were tested using the gradient test method. The efficacy of phenylalanine-arginine-β-naphthylamide (PAβN) as efflux pump inhibitors was assessed to determine their ability to reduce meropenem minimum inhibitory concentrations. Polymerase chain reaction (PCR) assays were conducted to identify blaIMP, blaVIM, and blaNDM-1.

 Among 114 strains of carbapenem-resistant P. aeruginosa, overall resistance rates for C/T and C/A were 10.7% and 8.8%, respectively. Efflux pump inhibitor-based antibiotic susceptibility testing indicated that 35.08% of strains showed resistance modulated by PAβN. Among the strains, 27 (24.5%) were found to produce metallo-beta-lactamase (MBL), with blaVIM (17 strains, 14.91%) being the most common, followed by blaIMP (12 strains, 10.53%).

 Emerging carbapenem resistance in P. aeruginosa strains is a serious therapeutic challenge for clinicians. Carbapenem resistance can be influenced by various factors, some of which were not assessed in our study. Nonetheless, our results revealed that the main mechanism associated with carbapenem-resistant P. aeruginosa strains is a PAβN-sensitive efflux pump. Among acquired MBLs, VIM-type enzymes were found to be the most prevalent.