Antibiotic resistance profiling and phylotyping of human-diarrheagenic Escherichia coli pathotypes detected from diarrheic and non-diarrheic calves in Iran.

BACKGROUND: Escherichia coli (E. coli) serves as a common indicator of gut microbiota and is utilized for monitoring antimicrobial resistance determinants in food-producing animals. This study aimed to investigate antimicrobial resistance patterns in virulence gene-positive E. coli isolates obtained from 340 healthy and diarrheic calves. METHODS AND RESULTS: A total of 340 fecal swab samples were obtained from diarrheic (n = 170) and healthy (n = 170) calves for 12 months from different farms in Kerman, Iran. The samples were phenotypically analyzed to detect E. coli isolates and antibiotic resistance. Also, antimicrobial resistance genes, diarrheagenic E. coli pathotypes, and phylogenetic background were screened by PCR. Fifteen percent (51/340) of E. coli isolates were positive for at least one of the examined virulence genes (VGs); the prevalence of VGs in E. coli isolates from healthy calves (36/170; 21.17%) was higher than that in diarrheic cases (15/170; 8.82%). Out of the 51 VG-positive isolates, six pathotypes including Shiga toxin-producing E. coli (STEC; 27.45%), enterotoxigenic E. coli (ETEC; 23.52%), enterohemorrhagic E. coli (EHEC; 19.6%), necrotoxigenic E. coli (NTEC; 19.6%), enteropathogenic E. coli (EPEC; 15.68%), enteroinvasive E. coli (EIEC; 1.96%) and three hybrid pathotypes including ETEC/STEC, ETEC/EHEC, and STEC/EIEC were detected among the strains. Antimicrobial resistance (AR) was observed in 98.03% of the VG-positive isolates, which was the same for both healthy and diarrheic calves. The maximum prevalence rate of AR was found against trimethoprim/sulfamethoxazole (49.01%; 3/51), while the minimum prevalence rate was against gentamycin (5.88%; 25/51). Among the VG-positives, phylotype A was found to be the most prevalent followed by B1 and D phylotypes. CONCLUSIONS: The prevalence of VG-positive E. coli isolates was higher in healthy calves compared to diarrheic cases. AR was widespread among VG-positive isolates. These findings suggest that calves may serve as potential reservoirs of antimicrobial-resistant hybrid pathotypes of E. coli.

High prevalence of ß-lactam and fluoroquinolone resistance in various phylotypes of Escherichia coli isolates from urinary tract infections in Jiroft city, Iran.

BACKGROUND: Urinary tract infection (UTI) is one of the most prevalent infectious diseases with worldwide health threatening. Antimicrobial resistant strains of Escherichia coli (E. coli) are a common cause of UTI which were identified as a treatment challenge. This study aimed to assay the prevalence of common ß-lactam resistance genes including blaTEM, blaSHV, blaCTX-M and blaCMY and phenotypic resistance to commonly used ß-lactam and fluoroquinolone antibiotics in UTIs. These factors were evaluated in various phylogenetic groups (phylotypes) of E. coli isolates. Real-time PCR was applied to detect ß-lactam resistance genes and conventional PCR was used to determine the phylotypes. Phenotypic resistance against ß-lactams (ceftazidime, cefotaxime, aztreonam and ceftriaxone) and fluoroquinolones (ciprofloxacin) were identified by the disc diffusion technique. The ability of extended spectrum ß-lactamases (ESBLs) production in E. coli isolates was detected using the combined disc diffusion method. RESULTS: The prevalence of resistance genes were 89.6% for blaTEM, 44.3% for blaCTX-M, 6.6% for blaSHV and 0.9% for blaCMY. The two high prevalent phylotypes were B2 (29.2%) and D (17.9%) followed by E (14.1%), F (9.4%), C (6.6%) and 10.3% of isolates were unknown in phylotyping. Disc diffusion results showed high prevalence of antibiotic resistance to cefotaxime (88.6%), aztreonam (83%), ceftireaxon (77.3%), ceftazidime (76.4%) and ciprofloxacin (55.6%). Totally, 52.8% of isolates were found as phenotypical ESBL-producers. CONCLUSIONS: This study's results confirmed an explosion of antibiotic resistance amongst E. coli isolates from UTI against ß-lactams and fluoroquinolones. Findings explain the necessity of deep changes in quantity and quality of drug resistance diagnosis and antibiotic therapy strategies. More studies are suggested to better and confident evaluations.

Clinical outcomes of zirconia implants: a systematic review and meta-analysis.

PURPOSE: To assess the clinical outcomes of zirconia dental implants based on an updated systematic literature review. METHODS: An electronic search was performed in three databases, last updated in June 2023, supplemented by hand searching. The eligibility criteria were clinical studies reporting patients rehabilitated with zirconia implants. The cumulative survival rate (CSR) of implants was calculated. A meta-analysis for marginal bone loss (MBL) under different follow-up times and a meta-regression assessing the relationship between mean MBL and follow-up were done. RESULTS: Twenty-five studies were included (4017 implants, 2083 patients). Seven studies had follow-up longer than 60 months. 172 implants failed, after a mean of 12.0 ± 16.1 months (min-max 0.3-86.0), of which 47 early failures, and 26 due to implant fracture, the majority in narrow-diameter implants. The 10-year CSR was 95.1%. Implants with coronal part prepared by drills presented statistically significant lower survival than non-prepared implants (p < 0.001). Two-piece implants presented lower survival than one-piece implants (p = 0.017). Implants discontinued from the market presented lower survival than the commercially available ones (p < 0.001). The difference in survival was not significant between implants in maxilla and mandible (p = 0.637). The mean MBL fluctuated between 0.632 and 2.060 mm over long periods of observation (up until 132 months). There was an estimated MBL increase of 0.005 mm per additional month of follow-up. CONCLUSION: Zirconia implants present high 10-year CSR and short-term low MBL. The review was registered in PROSPERO (CRD42022342055). CLINICAL RELEVANCE: The clinical outcomes observed for zirconia dental implants are very promising, although these have not yet been extensively studied as titanium alloy implants.

The emergence of carbapenem-resistance and New Delhi metallo-ß-lactamase-1 (blaNDM-1) among Salmonella spp. in Kerman, Iran.

Background and Objectives: Salmonella species (spp) are the most prevalent zoonotic pathogens that cause outbreaks of gastroenteritis worldwide. Therefore evaluation of the profile of antibiotic resistance, virulence factors, and plasmid replicon types in these bacteria is necessary to control and prevent the spread of potentially pathogenic and drug-resistant strains. Materials and Methods: This study was performed on 39 Salmonella spp. The antibacterial susceptibility of isolates to various antibiotic agents was determined using disk diffusion test. ß-lactamases (bla) including ESBLs, AmpC, MBLs, and virulence genes were detected by PCR methods. Plasmid incompatibility groups among the isolates were identified using PCR-based replicon typing (PBRT). Results: The most prevalent virulent gene was phoP/Q (84.6%). slyA, sopB, and stn were identified in 79.4% (n=31), 69.2% (n=27), and 2.5% (n=1) of the isolates, respectively. The antibiotic susceptibility testing showed that 30.7% of the isolates were ESBL-producing. blaTEM (41%; n=16) was the most frequent ß-lactamase gene among the isolates followed by blaNDM-1 (15.4%; n=6), blaDHA (7.7%; n=3), and blaCTX-M (1.5%; n=1). Six different plasmid replicon types, including IncP (n=9; 23%), IncFIC (n=3; 7.70%), IncY (n=3; 7.70%), IncI1-Iγ (n=2; 5.12%), IncFIIAs (n=1; 2.56%), and IncN (n=1; 2.56%) were observed among the isolates. Conclusion: Our study showed the emergence of carbapenem-resistant and blaNDM-1 among Salmonella spp. for the first time in Kerman, Iran. Since Salmonella spp. plays an important role in the transmission of resistance genes in livestock and humans in the food chains, so more stringent control policies are recommended to prevent the circulation of drug-resistant and potentially pathogenic strains from animals to humans.

Exploring the potential of cold plasma therapy in treating bacterial infections in veterinary medicine: opportunities and challenges.

Cold plasma therapy is a novel approach that has shown significant promise in treating bacterial infections in veterinary medicine. Cold plasma possesses the potential to eliminate various bacteria, including those that are resistant to antibiotics, which renders it a desirable substitute for traditional antibiotics. Furthermore, it can enhance the immune system and facilitate the process of wound healing. However, there are some challenges associated with the use of cold plasma in veterinary medicine, such as achieving consistent and uniform exposure to the affected area, determining optimal treatment conditions, and evaluating the long-term impact on animal health. This paper explores the potential of cold plasma therapy in veterinary medicine for managing bacterial diseases, including respiratory infections, skin infections, and wound infections such as Clostridium botulinum, Clostridium perfringens, Bacillus cereus, and Bacillus subtilis. It also shows the opportunities and challenges associated with its use. In conclusion, the paper highlights the promising potential of utilizing cold plasma in veterinary medicine. However, to gain a comprehensive understanding of its benefits and limitations, further research is required. Future studies should concentrate on refining treatment protocols and assessing the long-term effects of cold plasma therapy on bacterial infections and the overall health of animals.

The outcome of Iranian children on continuous ambulatory peritoneal dialysis: the first report of Iranian National Registry.

BACKGROUND: Continuous ambulatory peritoneal dialysis is not a very common modality to treat Iranian children with end-stage renal disease; however, there is sometimes no choice but to offer this therapy to salvage the patient. Obviously, promotion in each program needs re-evaluation to find the pitfalls. Therefore, a nation-wide survey on pediatric continuous ambulatory peritoneal dialysis was conducted to find the cause of death or termination of dialysis. METHODS: All children, younger than 14 years old, treated by continuous ambulatory peritoneal dialysis in nine main pediatric nephrology wards in Iran between 1993 and 2006 were included in this historical cohort study. Patient and technique survival rates were determined. Kaplan-Mayer and Cox-regression analysis were used to compare the survival. 2 x 2 table was used to calculate the risk ratio. A P<0.05 was considered significant. RESULTS: One hundred twenty children with a mean age of 47.6 months were on continuous ambulatory peritoneal dialysis. The most frequent cause of renal failure was hereditary-metabolic-cystic disease. One hundred eighty-two peritoneal dialysis catheters were inserted surgically. The median first catheter exchange was 0.74 year (95%CI: 0.5 - 0.98). The most frequent cause of catheter replacement was catheter outflow failure due to displacement, adhesion, and infection (persistent peritonitis or tunnel infection). The mean patient survival was 1.22 years (95%CI: 0.91 - 1.53). The mortality rate was 55% before 1997, and 60% between 1998 and 2001, which declined to 23% after 2002 (P<0.05). Young age (<24 months) was the only independent factor that predicted mortality (P<0.05). The outcome of children was as follows: recovery of renal function (6.7%), renal transplantation (8.3%), switch to hemodialysis (16.7%), still on continuous ambulatory peritoneal dialysis (23.3%), death (43.3%), and lost to follow-up (1.7%). CONCLUSION: The mortality is still high among Iranian children on peritoneal dialysis. Young age is the most important factor influencing on survival and mortality.

Uroflowmetry nomogram in Iranian children aged 7 to 14 years.

BACKGROUND: As the voiding habits of Iranian children differs from other children because of some cultural and religious considerations, we aimed to establish normal reference values of urinary flow rates in Iranian children between 7 to 14 years of age. METHODS: Eight hundred and two uroflowmetry studies were performed on children with no history of a renal, urological, psychological or neurological disorder, between the ages 7 and 14. Five hundred twenty five studies from 192 girls and 335 boys were considered in this study excluding the staccato/interrupted voiding pattern or voided volume less than 20 ml. The voiding volume, the maximum and average urinary flow rates were extensively analyzed. RESULTS: The maximal and average urine flow rate nomograms were plotted for both girls and boys. Mean maximum urine flow rate was 19.9 (ml/sec) for boys and 23.5 (ml/sec) for girls with a mean voided volume of 142 (ml) for boys and 147 (ml) for girls. Flow rates showed a close association with voiding volume in both sexes. The maximum and average flow rates were higher in girls than in boys, and they showed a significant increase in flow rates with increasing age, where boys did not. The mean maximum urine flow rates (19.9 ml/sec for boys and 23.5 ml/sec for girls) were found to be higher in this study than other studies. CONCLUSION: Nomograms of maximal and average flow rates of girls and boys are presented in centile form, which can help the physician to evaluate the response to medical or surgical treatment and be useful for the screening of lower urinary tract disturbances in children, for a wide range of voided volumes.

Effect of levamisole in steroid-dependent nephrotic syndrome.

INTRODUCTION. Childhood idiopathic nephrotic syndrome is characterized by frequent relapsing courses or steroid dependency. Levamisole is a popular drug for treatment of these patients. The purpose of this study was to evaluate levamisole in children with steroid-dependent nephrotic syndrome. MATERIALS AND METHODS. We retrospectively studied 304 children with a diagnosis of steroid-dependent nephrotic syndrome or frequently relapsing nephrotic syndrome. The mean age at the time of diagnosis was 4.84 years. Following induction of complete remission with steroid therapy based on the International Study of Kidney Disease in Children's protocol and when they were taking alternative days of steroid, 2.5 mg/kg of levamisole was administered. RESULTS. The steroid dose was significantly decreased (mean reduction of 0.39 ± 0.46 g to 0.33 ± 0.38 g) after treatment with levamisole (P < .001). The number of relapses also significantly decreased (mean reduction of 0.92 ± 0.98 episodes to 1.07 ± 1.20 relapses per year; P < .001). The 14.5-month administration of levamizole had a sensitivity of 67.5% and a specificity of 71.9% to reach a dose reduction of more than 50% in steroid therapy. The duration of levamizole treatment was associated with more than 50% reduction in the number of relapses (P < .001). A 14.5-month treatment with levamizole had a sensitivity of 62.3% and a specificity of 63.6% to reach a relapse reduction of more than 50%. CONCLUSIONS. Levamisole appears to be effective in prolonging the duration of remission and decreasing the steroid dose in children with steroid-dependent nephrotic syndrome.

Fungal peritonitis in Iranian children on continuous ambulatory peritoneal dialysis: a national experience.

INTRODUCTION: Fungal peritonitis (FP), causing catheter obstruction, dialysis failure, and peritoneal dysfunction, is a rare but serious complication of peritoneal dialysis. In this study, the frequency and risk factors of FP are evaluated in children who underwent peritoneal dialysis. MATERIALS AND METHODS: A retrospective multicenter study was performed at the 5 pediatric peritoneal dialysis centers in Iran from 1971 to 2006, and FP episodes among 93 children were reviewed. Risk ratios were calculated for the clinical and demographic variables to determine the risk factors of FP. RESULTS: Ninety-three children aged 39 months on average were included in study. Sixteen out of 155 episodes of peritonitis were fungi infections, all by Candida albicans. The risk of FP was higher in those with relapsing bacterial peritonitis (P = .009). Also, all of the patients had received antibiotics within the 1 month prior to the development of FP. Catheters were removed in all patients after 1 to 7 days of developing FP. Six out of 12 patients had catheter obstruction and peritoneal loss after the treatment and 5 died due to infection. CONCLUSIONS: Fungal peritonitis, accompanied by high morbidity and mortality in children should be reduced by prevention of bacterial peritonitis. Early removal of catheter after recognition of FP should be considered.

Serum zinc and copper levels in children with chronic renal failure.

UNLABELLED: We evaluated changes in serum zinc (Zn) and copper (Cu) levels in two groups of children with chronic renal failure (CRF)--children with CRF who were on regular hemodialysis (Group 1, n=40) and children with CRF who were on conservative management (Group 2, n=31)--and in one group of healthy children (Group 3, n=30). All of the participants in the study were between 5-18 years old, and the composition of the three groups was almost identical with respect to age and sex. The length of time the children in Group 1 had been on hemodialysis varied between 3 and 52 months (mean: 20.97+/-14.8 months). To evaluate the impact of the duration of dialysis on serum levels of Zn, we further sub-divided Group 1 patients into two subgroups: Subgroup A patients (n=20) had been on hemodialysis therapy for less than 18 months (mean: 8.85+/-4.83 months); Subgroup B patients (n=20) had been on hemodialysis therapy for longer than 18 months (mean: 33.1+/-10.86 months). The PIXE (proton-induced X-ray emission) was used for measuring the trace elements. RESULTS: The mean serum level of Zn was lower in the Group 1 (hemodialysis group) children than in the children of Group 2 (on conservative management) and group 3 (healthy children) (p<0.001), but the difference was not significant between Groups 2 and 3. No significant differences in serum levels of Cu were found among the three groups. The serum level of Zn was lower in Subgroup B than in Subgroup A (p<0.001). The correlation test showed that there was an inverse linear relation between the length of time the child was on the hemodialysis regimen and serum Zn levels. CONCLUSION: Chronic hemodialysis may lead to abnormalities in the serum levels of some trace elements in children with CRF that increase in severity with increasing duration of hemodialysis. Deficiencies of these trace elements--zinc in particular--may contribute to various conditions and symptoms in children undergoing chronic hemodialysis.