Background and aim: Currently, the rate of hospital-acquired infections due to drug-resistant Pseudomonas aeruginosa strains shows an increasing trend and remains one of the principal reasons for mortalilty in burn patients. This study aimed to investigate the prevalence of genes conferring resistance to carbapenems in P. aeruginosa isolates from burn patients. Methods: A total of 50 P. aeruginosa isolates were tested for antibiotic susceptibility and presence of multidrug-resistant (MDR) and extensively drug resistant (XDR) isolates, using phenotypic tests. Screening for genes conferring resistance to carbapenems was investigated by multiplex PCR method. Results: Susceptibility testing demonstrated the highest resistance against amikacin, ceftazidime (n=44/88% each), and gentamicin (84%), while colistin sulfate was the most effective antibiotic. The rate of MDR and XDR isolates was revealed as 50% and 40% respectively. We detected the following carbapenemase genes: blaNDM (32%), followed by blaOXA-48 (18%), and blaBIC-1 (14%). This study revealed a high antibiotic resistance in P. aeruginosa isolates with a total of 40% and 50% MDR and XDR isolates respectively, and 70% carbapenem resistance. The prevalence of carbapenem conferring genes tested among carbapenem-resistant isolates was demonstrated as 65.7%. Conclusion: Due to the prevalence of P. aeroginosa strains carrying blaOXA-48 and blaNDM genes in our hospital, more attention and implementation of effective control measures against nosocomial infection are recommended.
Definitive and rapid diagnosis of extrapulmonary tuberculosis (EPTB) is challenging since conventional techniques have limitations due to the paucibacillary nature of the disease. To increase the sensitivity of detection of Mycobacterium tuberculosis (MTB) in EPTB specimens, we performed a nested PCR assay targeting several genes of MTB on EPTB specimens. A total of 100 clinical specimens from suspected cases of EPTB were processed. Standard staining for acid fast bacilli (AFB) was performed as the preliminary screening test. Extracted DNAs from specimens were subjected to Nested PCR technique for the detection of five different MTB target genes of IS6110, IS1081, hsp65kd, mbp64, and mtp40. On performing AFB staining, only 13% of specimens were positive, of which ascites fluid (33.3%), followed by pleural effusion (30.8%) showed the greatest AFB positivity rate. We demonstrated slight improvement in yields in lymph node which comprised the majority of specimens in this study, by employing PCR targeted to IS6110- and hsp65-genes in comparison to AFB staining. However, the yields in ascites fluid and pleural effusion were not substantially improved by PCR, but those from bone and wound were, as in nested PCR employing either gene, the same positivity rate were obtained for ascites fluid (33.3%), while for pleural effusion specimens only IS1081 based PCR showed identical positivity rate with AFB stain (30.8%). The results for bone and wound specimens, however, demonstrated an improved yield mainly by employing IS1081 gene. Here, we report higher detection rate of EPTB in clinical specimens using five different targeted MTB genes. This nested PCR approach facilitates the comparison and the selection of the most frequently detected genes. Of course this study demonstrated the priority of IS1081 followed by mtp40 and IS6110, among the five tested genes and indicates the effectiveness of any of the three genes in the design of an efficient nested-PCR test that facilitates an early diagnosis of paucibacillary EPTB cases, which are difficult to diagnose with the available standard.
Present study was aimed to examine the diagnostic utility of polymerase chain reaction (PCR) and nested PCR techniques for the detection of Mycobacterium tuberculosis (MTB) DNA in samples from patients with extra pulmonary tuberculosis (EPTB). In total 80 formalin-fixed, paraffin-embedded (FFPE) samples comprising 70 samples with definite diagnosis of EPTB and 10 samples from known non- EPTB on the basis of histopathology examination, were included in the study. PCR amplification targeting IS6110, rpoB gene and nested PCR targeting the rpoB gene were performed on the extracted DNAs from 80 FFPE samples. The strong positive samples were directly sequenced. For negative samples and those with weak band in nested-rpoB PCR, TA cloning was performed by cloning the products into the plasmid vector with subsequent sequencing. The 95% confidence intervals (CI) for the estimates of sensitivity and specificity were calculated for each method. Fourteen (20%), 34 (48.6%), and 60 (85.7%) of the 70 positive samples confirmed by histopathology, were positive by rpoB-PCR, IS6110-PCR, and nested-rpoB PCR, respectively. By performing TA cloning on samples that yielded weak (n = 8) or negative results (n = 10) in the PCR methods, we were able to improve their quality for later sequencing. All samples with weak band and 7 out of 10 negative samples, showed strong positive results after cloning. So nested-rpoB PCR cloning revealed positivity in 67 out of 70 confirmed samples (95.7%). The sensitivity of these combination methods was calculated as 95.7% in comparison with histopathology examination. The CI for sensitivity of the PCR methods were calculated as 11.39–31.27% for rpoB-PCR, 36.44–60.83% for IS6110- PCR, 75.29–92.93% for nested-rpoB PCR, and 87.98–99.11% for nested-rpoB PCR cloning. The 10 true EPTB negative samples by histopathology, were negative by all tested methods including cloning and were used to calculate the specificity of the applied methods. The CI for 100% specificity of each PCR method were calculated as 69.15–100%. Our results indicated that nested-rpoB PCR combined with TA cloning and sequencing is a preferred method for the detection of MTB DNA in EPTB samples with high sensitivity and specificity which confirm the histopathology results.
Introduction This study aimed to evaluate the levels of sex hormones in patients with COVID‐19 in Ahvaz, Iran. Methods A prospective longitudinal study was conducted at Razi hospital, Ahvaz, Iran, from July 2020 to Febuary 2021. The levels of sex hormones including estradiol, progesterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), and total and free testosterone were measured in 162 patients with COVID‐19 infection during hospitalization and 1 month after discharge. A demographic questionnaire and a checklist were used to collect the data. Mann−Whitney U test, χ 2 test, Fisher's exact test, Wilcoxon test, and logistic regression were used to analyze the data. Results Sex hormones were assessed in 162 patients at baseline; however, a month after discharge, only 69 patients provided consent for assessment, and 9 had passed away. The estradiol level was 407.70 ± 623.37 and 213.78 ± 407.17 pg/ml in female patients with severe and moderate diseases at baseline, respectively which reduced to 195.33 ± 380.04 and 58.20 ± 39.45 pg/ml after discharge ( p = 0.011 and p = 0.001). The alteration in the levels of progesterone, LH, and FSH were not significant. The level of LH in both groups of male patients with severe (6.64 ± 2.91 IU) and moderate disease (6.42 ± 4.44 IU) was high, which reduced after discharge (4.16 ± 2.44 and 3.93 ± 3.15 IU, respectively), but this decrease was significant only in the patients with severe disease ( p < 0.0001). The alteration of FSH and free testosterone were not significant. The level of testosterone was 1.19 ± 0.73 and 1.46 ± 1.22 ng/ml at baseline in patients with severe and moderate diseases which increased to 2.64 ± 1.25 ng/ml, p < 0.0001, and 2.54 ± 0.93 ng/ml, p = 0.001, respectively after discharge. Conclusion Our findings showed that the level of estradiol in female patients increased significantly while the level of testosterone in male patients decreased during the active phase of infection. Due to the attrition of patients in the follow‐up period, more studies are needed to confirm these results.
The aim of this study was to analyze mutations occurring in the rpoB gene of Mycobacterium tuberculosis (MTB) isolates from clinical samples of extrapulmonary tuberculosis (EPTB). Seventy formalin-fixed, paraffin-embedded samples and fresh tissue samples from confirmed EPTB cases were analyzed. Nested PCR based on the rpoB gene was performed on the extracted DNAs, combined with cloning and subsequent sequencing. Sixty-seven (95.7%) samples were positive for nester PCR. Sequence analysis of the 81 bp region of the rpoB gene demonstrated mutations in 41 (61.2%) of 67 sequenced samples. Several point mutations including deletion mutations at codons 510, 512, 513 and 515, with 45% and 51% of the mutations in codons 512 and 513 respectively were seen, along with 26% replacement mutations at codons 509, 513, 514, 518, 520, 524 and 531. The most common alteration was Gln → His, at codon 513, presented in 30 (75.6%) isolates. This study demonstrated sequence alterations in codon 513 of the 81 bp region of the rpoB gene as the most common mutation occurred in 75.6% of molecularly confirmed rifampin-resistant strains. In addition, simultaneous mutation at codons 512 and 513 was demonstrated in 34.3% of the isolates.
Background Burn infection continues to be a major issue of concern globally and causes more harm to developing countries. This study aimed to identify the aerobic bacteriological profiles and antimicrobial resistance patterns of burn infections in three hospitals in Abadan, southwest Iran. Methods The cultures of various clinical samples obtained from 325 burn patients were investigated from January to December 2019. All bacterial isolates were identified based on the standard microbiological procedures. Antibiotic susceptibility tests were performed according to the CLSI. Results A total of 287 bacterial species were isolated burn patients.P. aeruginosa was the most frequent bacterial isolate in Gram-negative bacteria and S. epidermidis was the most frequent species isolated in Gram-positive bacteria. The maximum resistance was found to ampicillin, gentamicin, ciprofloxacin, while in Gram-negative bacteria, the maximum resistance was found to imipenem, gentamicin, ciprofloxacin, ceftazidime, and amikacin. The occurrence of multidrug resistance phenotype was as follows: P. aeruginosa (30.3 %), Enterobacter spp (11.1 %), Escherichia coli (10.5 %), Citrobacter spp (2.1 %), S. epidermidis (2.8 %), S. aureus, and S. saprophyticus (0.7 %). Conclusion Owing to the diverse range of bacteria that because burn wound infection, regular investigation, and diagnosis of common bacteria and their resistance patterns is recommended to determine the proper antibiotic regimen for appropriate therapy.
Background This study aimed to evaluate the occurrence of Streptococcus pneumoniae and Haemophilus influenzae in sputum of patients with community-acquired pneumonia (CAP) using culture and multiplex polymerase chain reaction (M-PCR) methods and to survey the antibiotic resistance patterns of aforesaid isolates. Result In total, 23.9 % (n = 22/92) of sputum samples showed positive results in the culture method. S. pneumoniae and H. influenzae were isolated from 15 (16.3 %) and 7 (7.6%) samples, respectively. Using M-PCR, 44 (47.8 %) samples were positive for S. pneumoniae and H. influenzae. Of these, S. pneumoniae and H. influenzae were detected in 33 (35.8%) and 11 (11.9%) of the sputum samples, respectively. The sensitivity, specificity, and accuracy rates of PCR in detection of S. pneumoniae in comparison with culture method were 100, 76.6, and 83.6%, respectively. While, the sensitivity, specificity, and accuracy rates of PCR in detection of H. influenzae in comparison with culture method were 100, 95.3, and 95.8%, respectively. Out of 11 isolates of H. influenzae, two strains confirmed as H. influenzae type b (Hib) and 3 isolates were type f. However, 6 isolates were non-typable. The co-trimoxazole and amoxicillin/clavulanate were the less effective antibiotics against S. pneumonia and H. influenzae, respectively. Ceftriaxone with 13.3% resistance rates was the most effective antibiotic against S. pneumoniae, while, clarithromycin, ceftriaxone, and gentamicin with resistance rates of 28.6% for each one were the most effective chemicals against H. influenzae isolates. Conclusion In this study, the prevalence of S. pneumoniae was more than H. influenzae using culture and M-PCR methods. The M-PCR provided better efficiency in detecting the bacterial agents in CAP patients compared to culture method. This method can improve the early detection of pathogens contributed to CAP. The drug resistant S. pneumoniae and H. influenzae indicated the need to develop a codified monitoring program to prevent further spread of these strains.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
334 Leonard St
Brooklyn, NY 11211
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.