Iranian Journal of Microbiology最新文献

{"title":"Immunological and virological response in HIV-1 infected patients receiving active antiretroviral therapy at a tertiary care center in Northern India.","authors":"Arti Agrawal, Anshika Chawla, Astha, Jitendra Kumar Doneria, Nitu Chauhan, Ayushi Gupta, Gargi Tyagi, Parul Garg","doi":"10.18502/ijm.v18i1.20936","DOIUrl":"10.18502/ijm.v18i1.20936","url":null,"abstract":"<p><strong>Background and objectives: </strong>Human Immunodeficiency Virus (HIV) remains a major global health challenge, with limited Indian data on factors influencing treatment outcomes. This study assessed immunological and virological responses and survival determinants among treatment-naïve HIV-1-positive adults.</p><p><strong>Materials and methods: </strong>A retrospective observational study was conducted at a tertiary care centre from May 2022 to April 2023. Adults (≥18 years) who initiated first-line ART (TDF + 3TC + DTG) between January 2019 and December 2020 with 24-month follow-up were included. Baseline demographics, CD4 count, viral load, and adherence were analysed using descriptive statistics and logistic regression.</p><p><strong>Results: </strong>Of 452 screened patients, 355 were eligible. Mortality at 6, 12, and 24 months was 22%, 26.8%, and 29.9%, respectively, with overall survival of 70.1%. Baseline CD4 count, viral load, adherence, and ART initiation timing significantly influenced outcomes (p < 0.05). Patients with baseline between 200 to 350 had almost 7 times the odds of survival compared to those with <200 cells/μL. Early ART initiation (≤7 days) improved survival (3-fold) and viral suppression (2.4-fold), while adherence >95% was the strongest predictor of success. Older age and high viral load predicted poorer outcomes.</p><p><strong>Conclusion: </strong>Early ART initiation, strict adherence, and favourable baseline markers significantly improved survival and suppression, supporting the \"test-and-treat\" approach and the UNAIDS 95-95-95 targets.</p>","PeriodicalId":14633,"journal":{"name":"Iranian Journal of Microbiology","volume":"18 1","pages":"102-111"},"PeriodicalIF":1.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13156832/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147868354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection and distribution of carbapenemase-encoding genes in clinical <i>Klebsiella pneumoniae</i> isolates from Kayseri, Türkiye.","authors":"Thowiba Yousif Jameel, Abdurrahman Ayvaz, Pınar Sağıroğlu, Mustafa Altay Atalay","doi":"10.18502/ijm.v18i1.20903","DOIUrl":"10.18502/ijm.v18i1.20903","url":null,"abstract":"<p><strong>Background and objectives: </strong>Carbapenem Resistance <i>Klebsiella pneumonia</i> (CRKP), mostly caused by carbapenemase enzymes, poses a serious public health threat due to limited treatment options. This study aimed to genotypically identify carbapenemase-encoding genes in CRKP isolates recovered from fecal swabs and to correlate these genotypes with phenotypic antibiotic resistance profiles.</p><p><strong>Materials and methods: </strong>In this study, fecal samples from 150 hospitalized patients were screened for <i>K. pneumoniae.</i> Phenotypic testing included the Phoenix automated system, CHROMagar KPC, biochemical tests, and disk diffusion assays. Genotypic analysis was performed using the BD MAX Checkpoint CPO PCR test, marking its first use in Kayseri, Türkiye, to detect carbapenemase genes in this pathogen.</p><p><strong>Results: </strong>Out of 150 fecal samples, 47 tested positive for <i>K. pneumoniae</i>, with 28 (59.6%) identified as carbapenem-resistant (CRKP). Molecular analysis identified five distinct carbapenemase gene patterns among these resistant isolates. The most prevalent gene, <i>bla</i> _OXA-48, was found alone in 60.7% of CRKP isolates, followed by <i>bla</i> _NDM in 3.6%; <i>bla</i> _KPC was not detected. Co-occurrence of genes was observed as follows: <i>bla</i> _OXA-48/<i>bla</i> _NDM (14.3%), <i>bla</i> _OXA-48 with <i>bla</i> _VIM /<i>bla</i> _IMP (10.7%), and <i>bla</i> _OXA-48 with <i>bla</i> _NDM and <i>bla</i> _VIM /<i>bla</i> _IMP (10.7%) in CRKP clinical isolates.</p><p><strong>Conclusion: </strong>The study found that <i>bla</i> _KPC was consistently absent, while <i>bla</i> _OXA-48 was highly prevalent and exhibited co-occurrences of carbapenemase genes. It underscored the need for strict hospital surveillance and effective infection control to prevent the spread of CRKP strains. Rapid molecular methods, such as the BD MAX multiplex PCR, have shown promise in accurately and efficiently identifying carbapenemase genes.</p>","PeriodicalId":14633,"journal":{"name":"Iranian Journal of Microbiology","volume":"18 1","pages":"23-31"},"PeriodicalIF":1.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13156824/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147868376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prophage typing of <i>Staphylococcus aureus</i> in traditional dairy products of Ilam, Iran.","authors":"Ali Abbas Hashemi, Mostafa Nemati, Fazel Pourahmad","doi":"10.18502/ijm.v18i1.20934","DOIUrl":"10.18502/ijm.v18i1.20934","url":null,"abstract":"<p><strong>Background and objectives: </strong>Antimicrobial resistance (AMR), particularly from methicillin-resistant <i>Staphylococcus aureus</i> (MRSA), poses a significant public health threat, exacerbated by antibiotic misuse in livestock and food production. This study aimed to evaluate the prevalence of MRSA in traditional dairy products from Ilam, Iran, and explore the role of prophages in enhancing bacterial virulence and resistance, assessing their implications for food safety.</p><p><strong>Materials and methods: </strong>Between January and April 2021, 116 dairy samples (raw milk, traditional cheese, and toof) were collected from Ilam, Iran. <i>Staphylococcus aureus</i> was identified using bacteriological and molecular methods, including PCR targeting <i>femA</i>, <i>mecA</i>, and prophage markers (SGB, SGFa, SGFb). Antibiotic susceptibility was tested via the Kirby-Bauer method, and data were analyzed using SPSS.</p><p><strong>Results: </strong><i>S. aureus</i> was detected in 25.9% of samples (30/116), with raw milk showing the highest contamination (57.9%). MRSA, identified by the <i>mecA</i> gene, was present in 6.7% of isolates, and 73.3% exhibited multidrug resistance. Prophages were found in 13.3% of isolates, with SGB linked to β-lactam resistance (p = 0.04). High resistance to doxycycline (87%) and tetracycline (67%) was observed.</p><p><strong>Conclusion: </strong>The study highlights a significant presence of MRSA and multidrug-resistant <i>S. aureus</i> in Ilam's dairy products, with prophages contributing to the virulence of these bacteria. Enhanced hygiene and monitoring are crucial for mitigating food safety risks.</p>","PeriodicalId":14633,"journal":{"name":"Iranian Journal of Microbiology","volume":"18 1","pages":"82-90"},"PeriodicalIF":1.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13156833/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147868409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Burden and resistance of Gram-negative pathogens in ICU-acquired infections in Vietnam: a cross-sectional study.","authors":"Do Quoc Phong, Vu Hai Vinh, Dang Hai Van, Tran Minh Hieu, Tran Thi Mai Huong, Le Thi Thuong, Le Huynh Duc, Nguyen Thi Mai Huong","doi":"10.18502/ijm.v18i1.20904","DOIUrl":"10.18502/ijm.v18i1.20904","url":null,"abstract":"<p><strong>Background and objectives: </strong>This study aimed to describe the burden, pathogen distribution, antimicrobial resistance patterns, and selected clinical outcomes of intensive care unit (ICU)-acquired Gram-negative bacteria (GNB) infections in Vietnam, with exploratory comparative analyses of outcomes.</p><p><strong>Materials and methods: </strong>A retrospective descriptive study with comparative analyses was conducted among 102 adult patients with culture-confirmed ICU-acquired GNB infections at E Hospital, Hanoi. Demographic, clinical, microbiological, and outcome data were extracted from medical records. Antimicrobial susceptibility testing was performed according to Clinical and Laboratory Standards Institute guidelines. Comparisons between outcome groups were assessed using chi-square test, with effect sizes quantified using Cramer's V.</p><p><strong>Results: </strong>Pneumonia was the predominant infection (70.5%), followed by urinary tract (15.2%) and bloodstream infections (10.6%). GNB accounted for 68.3% of all hospital-acquired infections (HAIs), with <i>Acinetobacter baumannii</i> (43.4%), <i>Pseudomonas aeruginosa</i> (24.8%), and <i>Klebsiella pneumoniae</i> (13.9%) being the most frequent pathogens. The predominant pathogens exhibited extensive resistance to β-lactams, cephalosporins, and carbapenems. Susceptibility was largely retained only to colistin, tigecycline, and amikacin. Mechanical ventilation was significantly associated with death or a severe clinical outcome (p = 0.03; Cramer's V = 0.21).</p><p><strong>Conclusion: </strong>GNB dominate ICU-acquired infections in Vietnam and demonstrate alarming antimicrobial resistance, underscoring the urgent need for strengthened infection control and antimicrobial stewardship.</p>","PeriodicalId":14633,"journal":{"name":"Iranian Journal of Microbiology","volume":"18 1","pages":"32-40"},"PeriodicalIF":1.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13156818/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147868259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative evaluation of outer membrane protein and whole cell antigen vaccine against avian pathogen <i>Escherichia coli</i> infection in broiler chicken.","authors":"Basharat Maqbool Wani, Shayaib Ahmad Kamil, Showkat Ahmad Shah, Masood Saleem Mir, Mir Nadeem Hassan, Zahid Amin Kashoo, Mudasir Ali Rather, Majid Shafi, Zahoor Ahmad Wani, Nadeem Shabir, Nazli Tizro, Akeel Bashir, Atif Khurshid Wani","doi":"10.18502/ijm.v18i1.20935","DOIUrl":"10.18502/ijm.v18i1.20935","url":null,"abstract":"<p><strong>Background and objectives: </strong>Present study was aimed at assessing protective efficacy of outer membrane protein (OMP) vaccine in comparison to inactivated whole cell antigen vaccine after challenge with homologous serogroup (O2) of avian pathogenic <i>Escherichia coli</i> in broiler chickens.</p><p><strong>Materials and methods: </strong>The outer membrane proteins were extracted by sarcosyl method and protein concentration was determined by nanodrop spectrophotometer. The study comprised of 120 birds divided into 6 groups. The birds were subcutaneously immunized twice with primary vaccine in the first week followed by booster vaccine in second week.</p><p><strong>Results: </strong>The protection rate of 82% was found in whole cell inactivated antigen, 91% in OMP vaccine and 27% among the unvaccinated group. The antibody (IgG) response was found significantly higher in OMP vaccine group than whole cell antigen group. In unvaccinated groups chicks, the antibody titer never reached to the protective level till the termination of experiment. The bacteria were re-isolated from the infected broiler chickens for the confirmation of induced infection and were characterized using standard cultural and biochemical tests belonging to O2 serogroup.</p><p><strong>Conclusion: </strong>Our study demonstrated that the outer membrane protein (OMP) vaccine provided significantly higher protection (91%) and antibody response compared to the inactivated whole cell antigen vaccine (82%) against <i>Escherichia coli</i> O2 infection in broiler chickens. Birds vaccinated with OMP exhibited fewer pathological lesions and a stronger immune response. The findings underscore the potential of OMP-based vaccines as a safer, more immunogenic alternative for controlling colibacillosis.</p>","PeriodicalId":14633,"journal":{"name":"Iranian Journal of Microbiology","volume":"18 1","pages":"91-101"},"PeriodicalIF":1.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13156834/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147868348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clinical profile and outcome of COVID-19 associated mucormycosis in Shiraz, South Iran: a longitudinal study.","authors":"Pariya Kouhi, Seyed Alireza Mirhosseini, Maryam Ranjbar, Mohammadreza Akbari, Zeinab Mehrabi, Rojan Javaheri, Mahsa Moosavi, Mohammad Alishahi, Kamran Rasekh, Nazanin Fathi, Yasaman Mansoori","doi":"10.18502/ijm.v18i1.20940","DOIUrl":"10.18502/ijm.v18i1.20940","url":null,"abstract":"<p><strong>Background and objectives: </strong>Numerous cases of mucormycosis appeared among COVID-19 patients, predominantly in Asian countries. This study aimed to investigate the clinical profile, in-hospital outcome, and one-year prognosis of COVID-19-associated mucormycosis (CAM).</p><p><strong>Materials and methods: </strong>All patients who developed CAM in Shiraz, South Iran, between July and October 2021 were included in this study. We collected data on presentations, comorbidities, risk factors, and outcomes.</p><p><strong>Results: </strong>Sixty-two patients with CAM were analyzed; the mean age was 59.3 years, and 58.1% were male. Diabetes mellitus was present in 80.6% (11.2% uncontrolled), hypertension in 54.8%, and chronic kidney disease in 11.3%. All patients had sinonasal involvement; ophthalmic, cutaneous, cerebral, gastrointestinal, pulmonary, and renal involvement occurred in 41.9%, 8.1%, 6.4%, 6.4%, 1.6%, and 1.6%, respectively. In-hospital and one-year mortality were 40.3% and 48.3%. Concurrent CAM and COVID-19, hypertension, older age, and radiologically severe COVID-19 lung involvement were associated with higher mortality. In multivariable analysis, age ≥60 years predicted in-hospital (OR: 5.47; 95% CI: 1.53-19.56) and one-year mortality (OR: 7.65; 95% CI: 1.90-30.84). Long-term mortality was also associated with ≥3 risk factors (OR: 4.12; 95% CI: 1.09-15.52) and lung severity index >30 (OR: 9.35; 95% CI: 1.01-86.63).</p><p><strong>Conclusion: </strong>These findings emphasize the critical role of age in immune responses to opportunistic infections and highlight the impact of multiple comorbidities and severe lung damage on long-term prognosis in CAM.</p>","PeriodicalId":14633,"journal":{"name":"Iranian Journal of Microbiology","volume":"18 1","pages":"147-156"},"PeriodicalIF":1.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13156837/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147868317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Drug susceptibility of <i>Candida albicans</i> and non-<i>albicans Candida</i> species isolated from ornamental birds.","authors":"Zahra Mirhosseini, Jamshid Razmyar, Alireza Khosravi","doi":"10.18502/ijm.v18i1.20941","DOIUrl":"10.18502/ijm.v18i1.20941","url":null,"abstract":"<p><strong>Background and objectives: </strong>The prevalence of <i>Candida</i> infections, especially by non-<i>albicans Candida</i> species, has led to excessive use of antifungal drugs, resulting in the transfer of resistance and increased minimum inhibitory concentration (MIC) among <i>Candida</i> isolates. This study aimed to investigate the susceptibility of clinical <i>Candida</i> isolates of ornamental birds to three antifungal drugs: amphotericin B, caspofungin, and itraconazole.</p><p><strong>Materials and methods: </strong>Totally 126 samples were analyzed, from which 116 distinct colonies were cultured. Of these, 26 were identified as <i>Candida</i> spp., comprising 12 <i>C. albicans</i> (46.1%), 8 <i>C. tropicalis</i> (30%), 1 <i>C. glabrata</i> (3%), 1 <i>C. krusei</i> (3%), and 4 isolates (15%) of other <i>Candida</i> species. The present study aimed to determine the susceptibility and resistance levels of these <i>Candida</i> isolates to three antifungal drugs: amphotericin B, caspofungin, and itraconazole.</p><p><strong>Results: </strong>According to the CLSI M44 recommended method, by the disk diffusion method, itraconazole (100%) and amphotericin B (86.46%) showed the best susceptibility pattern, compared to caspofungin (0%).</p><p><strong>Conclusion: </strong>Given that the isolates showed the highest in vitro susceptibility to itraconazole and amphotericin B and the lowest to caspofungin, these findings suggest that itraconazole and amphotericin B could be considered potential first-line agents for treating avian candidiasis.</p>","PeriodicalId":14633,"journal":{"name":"Iranian Journal of Microbiology","volume":"18 1","pages":"157-164"},"PeriodicalIF":1.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13156831/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147868421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Candiduria in catheterized ICU patients: epidemiology, molecular identification, and antifungal susceptibility.","authors":"Ali Ahmadi, Ebrahim Hazrati, Mahtab Noorifard, Zohreh Farahnejad, Mojgan Mohammadimehr","doi":"10.18502/ijm.v18i1.20939","DOIUrl":"10.18502/ijm.v18i1.20939","url":null,"abstract":"<p><strong>Background and objectives: </strong>Candiduria related to urinary catheters is frequently encountered in patients hospitalized in intensive care units. The diagnosis and management of catheter-associated candiduria in hospitalized patients is frequently a gray area for both physicians and microbiologists because of the paucity of clinical and microbiological data.</p><p><strong>Materials and methods: </strong>This cross-sectional study aims to enhance the understanding of candiduria among adult ICU patients with urinary catheters across three hospitals in Tehran, Iran. Yeast identification was performed using a two-step multiplex PCR, and antifungal susceptibility testing was performed following the CLSI M27, 4^th edition, recommendations.</p><p><strong>Results: </strong>Among the 110 enrolled ICU patients, 38 (35%) had significant candiduria. A total of 45 yeast isolates were collected. The distribution was as follows: <i>Candida glabrata</i> (23/45; 51%), <i>C. albicans</i> (14/45; 31%), and <i>C. tropicalis</i> (4/45; 9%). These three species accounted for 91% of the isolates. Antifungal resistance was detected: six isolates (two <i>C. glabrata</i>, two <i>C. albicans</i>, one <i>C. krusei</i>, and one <i>C. tropicalis</i>) were fluconazole-resistant, and one <i>C. glabrata</i> isolate was resistant to itraconazole, voriconazole, and caspofungin. All isolated species were susceptible to amphotericin B. Symptomatic candiduria occurred in 29% of cases (11/38); only 55% (6/11) were treated, and of those, 50% (3/6) experienced fluconazole treatment failure. One symptomatic patient developed candidemia shortly after acquiring candiduria. The mortality rate was 21% (8/38), with no apparent difference in death rates between symptomatic and asymptomatic candiduric patients.</p><p><strong>Conclusion: </strong>Our findings reveal that high fluconazole failure rates among patients with symptomatic candiduria are concerning. Furthermore, speciation and antifungal susceptibility testing are crucial, as they guide clinicians in selecting the most effective agent and improving case management.</p>","PeriodicalId":14633,"journal":{"name":"Iranian Journal of Microbiology","volume":"18 1","pages":"138-146"},"PeriodicalIF":1.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13156828/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147868274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Detection and prevalence of the <i>bla</i> _NDM-1 gene in carbapenem-resistant <i>Klebsiella pneumoniae</i> bloodstream isolates from a tertiary care institute.","authors":"Susheem Ramakrishnan, Gulnaz Bashir, Nargis Kaur Bali, Sabah Rashid, Dona Mathew, Qounser Nisar, Mohd Iqbal Mir","doi":"10.18502/ijm.v18i1.20902","DOIUrl":"10.18502/ijm.v18i1.20902","url":null,"abstract":"<p><strong>Background and objectives: </strong>Carbapenem resistance mediated by <i>bla</i> _NDM-1 in <i>Klebsiella pneumoniae</i> has emerged as a major challenge, particularly in intensive care settings with high antibiotic pressure. This compromises therapeutic options and contributes to poor clinical outcomes. The present study aimed to determine the prevalence of <i>bla</i> _NDM-1 among isolates of <i>K. pneumoniae</i> from a tertiary care hospital, evaluate the performance of phenotypic tests against PCR-based detection, assess antimicrobial susceptibility profiles, and analyze clinical outcomes.</p><p><strong>Materials and methods: </strong>In this study, over 18 months, 130 non-duplicate <i>K. pneumoniae</i> isolates were identified, and antimicrobial susceptibility testing was performed by VITEK-2 Compact and broth microdilution for colistin. Imipenem-resistant isolates were subjected to the Combined disc diffusion test (CDDT) and Double disc synergy test (DDST) for metallo-beta-lactamase (MBL), and conventional PCR targeting <i>bla</i> _NDM-1. Demographic data and outcomes were recorded.</p><p><strong>Results: </strong>Of the 130 isolates, 111 were imipenem-resistant, of which CDDT detected MBLs in 94.6%, and DDST detected MBLs in 76.6%. PCR confirmed <i>bla</i> _NDM-1 in 77.5% and was more commonly associated with cases of sepsis. <i>bla</i> _NDM-1 -positive isolates were resistant to β-lactams, fluoroquinolones and aminoglycosides. No isolate was found to be colistin-resistant. 26.7% of the patients with <i>bla</i> _NDM-1-positive bacteremia died.</p><p><strong>Conclusion: </strong>This study highlights the high prevalence of <i>bla</i> _NDM-1 in <i>K. pneumoniae</i> isolates. Among the phenotypic tests, CDDT outperformed DDST and showed the best agreement with PCR, supporting its use as a screening method for MBL, but confirmatory PCR remains essential. The restricted treatment options underscore the need for stringent infection control and robust antimicrobial stewardship to curb transmission and preserve last-line agents.</p>","PeriodicalId":14633,"journal":{"name":"Iranian Journal of Microbiology","volume":"18 1","pages":"14-22"},"PeriodicalIF":1.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13156820/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147868343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aflatoxin-producing <i>Aspergillus flavus</i> from food samples in Nepal.","authors":"Suprina Sharma, Dev Raj Joshi, Pramod Poudel, Supriya Sharma, Tika Bahadur Karki, Reshma Tuladhar","doi":"10.18502/ijm.v18i1.20942","DOIUrl":"10.18502/ijm.v18i1.20942","url":null,"abstract":"<p><strong>Background and objectives: </strong>Maize and peanuts, staple foods in Nepal, are highly susceptible to fungal contamination, particularly with aflatoxin-producing <i>Aspergillus flavus</i>. This study aimed to detect aflatoxin-producing <i>A. flavus</i> in maize and peanut samples collected from different regions of Nepal.</p><p><strong>Materials and methods: </strong>A total of 80 maize and 20 peanut samples were collected randomly from markets and households. Disinfected samples were inoculated on Potato Dextrose Agar and incubated at 28°C for 48 hours. <i>A. flavus</i> was identified by conventional cultural methods. Aflatoxin production was screened on <i>Aspergillus</i> Differential Medium (ADM) and confirmed through Thin Layer Chromatography (TLC) and High Performance Liquid Chromatography (HPLC).</p><p><strong>Results: </strong>Fungal contamination was detected in 67.0% of samples, with a significantly higher rate in household-stored samples (p = 0.00039). <i>A. flavus</i> was the predominant species, particularly in maize (72.5%). Of 50 <i>A. flavus</i> isolates, 15 (30%) were aflatoxin positive on ADM, with 11 (73.3%) being confirmed by TLC. HPLC revealed AFB1 as the most prevalent in both maize and peanuts, while AFB2 was restricted to maize.</p><p><strong>Conclusion: </strong>Maize and peanuts are highly susceptible to contamination with aflatoxin producing <i>A. flavus</i> in Nepal, particularly in household-stored samples, emphasizing significant food safety concerns.</p>","PeriodicalId":14633,"journal":{"name":"Iranian Journal of Microbiology","volume":"18 1","pages":"165-171"},"PeriodicalIF":1.9,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13156825/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147868331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}