{"title":"Adult cutaneous diphtheria by non-toxicogenic strain: Case report and review of literature","authors":"Khyati , Benu Dhawan , Vikas Gautam , Nishant Shekhar , Neetu Bhari , Jaya Biswas , Pranav Rai , Ritika Dhakad , Bimal Kumar Das","doi":"10.1016/j.ijmmb.2025.100892","DOIUrl":"10.1016/j.ijmmb.2025.100892","url":null,"abstract":"<div><div>We report an unusual case of recurrently infected post-folliculitis keloid. The diagnosis of cutaneous diphtheria was made by isolation of <em>Corynebacterium diphtheriae</em> cultured from pus collected from the skin lesion. The strain was non-toxigenic on multiplex real-time PCR assay. A prior pus sample from the lesion had grown Methicillin resistant <em>Staphylococcus aureus</em> (MRSA). The patient was treated with oral erythromycin for 14-days. Chemoprophylaxis was advised to the close contacts. The present case emphasizes the importance of investigation for unusual etiologies in patients with non-responding ulcerative cutaneous lesions. Early diagnosis of cutaneous diphtheria is required for appropriate treatment and effective control measures.</div></div>","PeriodicalId":13284,"journal":{"name":"Indian Journal of Medical Microbiology","volume":"56 ","pages":"Article 100892"},"PeriodicalIF":1.4,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144255329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mauricio Gabriel E.L. Silva , Karla Fabiane L. Melo , Samir M.M. Casseb , Eliana V.P. Silva , Ana Cecília R. Cruz , Carlos Alberto M. Carvalho
{"title":"Heterologous interference between Mayaro and Chikungunya viruses in Vero cells","authors":"Mauricio Gabriel E.L. Silva , Karla Fabiane L. Melo , Samir M.M. Casseb , Eliana V.P. Silva , Ana Cecília R. Cruz , Carlos Alberto M. Carvalho","doi":"10.1016/j.ijmmb.2025.100891","DOIUrl":"10.1016/j.ijmmb.2025.100891","url":null,"abstract":"<div><h3>Purpose</h3><div>Mayaro virus (MAYV) and Chikungunya virus (CHIKV) are arthritogenic alphaviruses with distinct natural vectors but common vertebrate hosts, whose concomitant circulation in Central and South America provides opportunities for mixed infections in humans. In view of this, we aimed to investigate the heterologous interference between these arboviruses during coinfections and superinfections in a primate cell line.</div></div><div><h3>Methods</h3><div>Experimental infections with MAYV and CHIKV were performed singly, simultaneously or consecutively, and cytopathic effect, cell viability and virus load were assessed by phase contrast light microscopy, fluorimetry and reverse transcription-quantitative polymerase chain reaction, respectively.</div></div><div><h3>Results</h3><div>All infection schemes led to a strong cytopathic effect accompanied by an average reduction of almost 90 % in cell viability within 24 h post-infection. Although there was no statistically significant difference between the loads of both viruses in coinfections, a decrease in the individual virus load of more than 90 % when compared to their respective single infections was observed. Furthermore, superinfections resulted in widely significant differences in the amount of progeny formed for each virus, with a first-mover advantage regardless of the species.</div></div><div><h3>Conclusions</h3><div>MAYV and CHIKV are subject to heterologous interference during coinfections and superinfections in primate cells, which could possibly impact disease outcome in humans.</div></div>","PeriodicalId":13284,"journal":{"name":"Indian Journal of Medical Microbiology","volume":"56 ","pages":"Article 100891"},"PeriodicalIF":1.4,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analysis of human Metapneumovirus infections in Mumbai (2017–2024)","authors":"Aruna Poojary , Anurag Kumar Bari , Seema Rohra","doi":"10.1016/j.ijmmb.2025.100890","DOIUrl":"10.1016/j.ijmmb.2025.100890","url":null,"abstract":"","PeriodicalId":13284,"journal":{"name":"Indian Journal of Medical Microbiology","volume":"56 ","pages":"Article 100890"},"PeriodicalIF":1.4,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144240570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gautam Barik, Gnanadurai John Fletcher, Diviya Alex, John Paul Demosthenes, Priya Abraham, Rajesh Kannangai
{"title":"HIV vaccine – Is there a ray of hope in the rugged journey?","authors":"Gautam Barik, Gnanadurai John Fletcher, Diviya Alex, John Paul Demosthenes, Priya Abraham, Rajesh Kannangai","doi":"10.1016/j.ijmmb.2025.100885","DOIUrl":"10.1016/j.ijmmb.2025.100885","url":null,"abstract":"<div><h3>Background</h3><div>The path of HIV vaccine development is riddled with numerous challenges. The high mutation and recombination rate of the virus, the establishment of a viral reservoir early in infection, and the failure to mount an effective immune response have added to the complexities of vaccine development.</div></div><div><h3>Objective</h3><div>In this review, we tried to revisit the vaccine development efforts, categorize the immunogens based on the immune response they tried to elicit and discuss the limited success or failure they achieved so far.</div></div><div><h3>Content</h3><div>The initial efforts of vaccine development concentrated on a three-pronged approach, induction of neutralizing antibodies, induction of cell-mediated immunity, or a combination of the two. Since then, the efforts to develop an effective immunogen have come a long way through the usage of poxviral vectors, conserved immunogens, and mosaic immunogens to the current trend of using mRNA-based vaccines, engineered outer domains on scaffold proteins and the development of germline targeting immunogens for induction of broadly neutralizing antibody-producing B-cell lineage. We also tried to narrate the current trends and the future directions of HIV vaccine development.</div></div>","PeriodicalId":13284,"journal":{"name":"Indian Journal of Medical Microbiology","volume":"56 ","pages":"Article 100885"},"PeriodicalIF":1.4,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144230194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Varied synergistic activity of colistin and polymyxin B with meropenem, rifampicin and tigecycline: An in vitro study on carbapenem resistant Acinetobacter baumannii from India","authors":"Manasa Tantry , Muralidhar Varma , Shwethapriya Rao , Chiranjay Mukhopadhyay , Vandana Kalwaje Eshwara","doi":"10.1016/j.ijmmb.2025.100889","DOIUrl":"10.1016/j.ijmmb.2025.100889","url":null,"abstract":"<div><h3>Purpose</h3><div>Effective therapeutic choices for infections by carbapenem resistant <em>Acinetobacter baumannii</em> (CRAB) in resource constrained settings is limited. Prospective antimicrobial combinations with polymyxins, need to be tested for synergy to mitigate further development of resistance. This study evaluates the synergistic effects of colistin and polymyxin B combined with meropenem, rifampicin, and tigecycline against CRAB isolates from bloodstream infections.</div></div><div><h3>Methods</h3><div>Twenty-five epidemiologically distinct CRAB strains were included. The minimum inhibitory concentrations (MICs) of the antimicrobials were determined by broth microdilution. The synergistic activities of the antimicrobial combinations were evaluated by checkerboard broth microdilution (CBM). Antimicrobials were tested at concentrations from 4 to 8 times down to 1/8–1/16 of their expected MIC, with a final inoculum of 10<sup>5</sup> CFU/mL. The antimicrobial combinations that demonstrated greater synergistic activity were confirmed using the time-kill assay (TKA).</div></div><div><h3>Results</h3><div>None of the strains were resistant to polymyxins (MIC ≤4 mg/L). Colistin-meropenem, colistin-rifampicin and colistin-tigecycline combinations achieved superior synergy over the polymyxin B-meropenem, polymyxin B-rifampicin and polymyxin B-tigecycline combinations (<em>P</em>=<0.001, <em>P</em> = 0.03, and <em>P</em> = 0.01, respectively) in the CBM assay. In the TKA, combinations of colistin (0.1–0.5 mg/L) with subinhibitory concentrations of meropenem (4–8 mg/L), rifampicin (1–4 mg/L), and tigecycline (0.06–0.25 mg/L) exhibited synergistic and bactericidal activity against a subset of isolates at 24 h.</div></div><div><h3>Conclusions</h3><div>Significant concordance between the CBM and TKA was observed. Our findings suggest that subinhibitory antimicrobial concentrations in combinations can improve therapeutic efficacy and minimize polymyxin side effects. Additionally, in vivo studies are warranted to optimize the combinational therapy.</div></div>","PeriodicalId":13284,"journal":{"name":"Indian Journal of Medical Microbiology","volume":"56 ","pages":"Article 100889"},"PeriodicalIF":1.4,"publicationDate":"2025-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144203310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ruma Das, Hitender Gautam, Priyam Batra, Bimal K. Das
{"title":"The importance of stool antigen test in the diagnosis and management of Helicobacter pylori infections","authors":"Ruma Das, Hitender Gautam, Priyam Batra, Bimal K. Das","doi":"10.1016/j.ijmmb.2025.100888","DOIUrl":"10.1016/j.ijmmb.2025.100888","url":null,"abstract":"","PeriodicalId":13284,"journal":{"name":"Indian Journal of Medical Microbiology","volume":"56 ","pages":"Article 100888"},"PeriodicalIF":1.4,"publicationDate":"2025-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144208426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Black swimming dots in cell culture: first report of Bradyrhizobium as a cause","authors":"Jasleen Kaur, Manisha Biswal","doi":"10.1016/j.ijmmb.2025.100887","DOIUrl":"10.1016/j.ijmmb.2025.100887","url":null,"abstract":"<div><h3>Introduction</h3><div>Black swimming dots (BSDs) are a frequent concern for scientists performing cell culture experiments. Despite this, there is very limited literature on this phenomenon. There is one report of <em>Achromobacter</em> species as the causative organism of black swimming dots in cell culture. In this study, we have revealed a 16S ribosomal RNA (bacterial rrs gene) full gene-based confirmation of black swimming dots as <em>Bradyrhizobium</em> species in our cell culture experiments. <em>Bradyrhizobium</em> is primarily a soil-dwelling bacteria, carrying out nitrogen fixation in legume roots.</div></div><div><h3>Methodology</h3><div>After inoculating the patient blood in L929 cell lines, DNA (deoxyribonucleic acid) isolation was performed on the seventh day from the trypsinized L929 cells. The culture flask under the tissue culture inverted microscope showed small moving dots in the field. The DNA extracted from the infected cell culture was then subjected to conventional PCR (Polymerase Chain Reaction) with the three sets of pan-bacterial primers targeting the full-length 16S ribosomal RNA gene.</div></div><div><h3>Results</h3><div>Our study reveals the contamination of mammalian cell culture with the black swimming dots caused by <em>Bradyrhizobium</em> species bacteria.</div></div><div><h3>Conclusion</h3><div>The 16S rRNA full gene analysis revealed that the black swimming dots in our cell culture flasks were due to <em>Bradyrhizobium</em> species. This study further clarifies that the BSDs in cell culture caused due to <em>Bradyrhizobium</em> species could not be cleared by 10 μg/ml concentration of both the antibiotics, piperacillin and ciprofloxacin.</div></div>","PeriodicalId":13284,"journal":{"name":"Indian Journal of Medical Microbiology","volume":"56 ","pages":"Article 100887"},"PeriodicalIF":1.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144198907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Nipah virus in India","authors":"Dheeraj Sharma","doi":"10.1016/j.ijmmb.2025.100884","DOIUrl":"10.1016/j.ijmmb.2025.100884","url":null,"abstract":"","PeriodicalId":13284,"journal":{"name":"Indian Journal of Medical Microbiology","volume":"56 ","pages":"Article 100884"},"PeriodicalIF":1.4,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144191722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chong Sun , He Diao , Xinying Zhang , Zhehui Han , Jiaqi Wei
{"title":"Study on human papillomavirus (HPV) infection, typing, peripheral blood immune factor expression and vaginal microenvironment balance in cervical cancer screening population","authors":"Chong Sun , He Diao , Xinying Zhang , Zhehui Han , Jiaqi Wei","doi":"10.1016/j.ijmmb.2025.100883","DOIUrl":"10.1016/j.ijmmb.2025.100883","url":null,"abstract":"<div><h3>Background</h3><div>Cervical cancer (CC) is a leading cause of cancer-related deaths among women, primarily driven by persistent high-risk human papillomavirus (HPV) infection. This study explores HPV prevalence, genotypes, and their associations with peripheral blood immune factors and vaginal microenvironment balance in a CC screening population.</div></div><div><h3>Methods</h3><div>A total of 2467 women undergoing CC screening from January to June 2024 were included. Among these, 227 tested positive for HPV (infection rate: 9.20 %). Using random sampling and propensity score matching, 100 HPV-positive and 100 HPV-negative individuals were selected. The HPV-positive group was further divided into HPV16/18 and other HPV subtypes. Samples from cervical cells, secretions, and peripheral blood were analyzed for HPV genotyping, vaginal microenvironment parameters (pH, cleanliness, Trichomonas, hydrogen peroxide-producing bacteria), Th1/Th2 cytokines (IL-6, IL-10, TNF-α), and T cell subsets (CD4<sup>+</sup>, CD8<sup>+</sup>).</div></div><div><h3>Results</h3><div>HPV-positive patients exhibited higher vaginal pH, abnormal vaginal cleanliness, and elevated hydrogen peroxide-producing bacteria compared to HPV-negative patients (<em>P</em> < 0.05). HPV16/18-positive individuals had greater vaginal alterations than other HPV subtypes. CD4<sup>+</sup> counts and CD4+/CD8+ ratios were significantly lower in HPV-positive groups, especially HPV16/18, alongside elevated IL-6 and IL-10 levels (<em>P</em> < 0.05). CD8<sup>+</sup> counts and TNF-α showed no significant differences (<em>P</em> > 0.05).</div></div><div><h3>Conclusion</h3><div>HPV, particularly HPV16/18, is associated with immune imbalance and vaginal microenvironment disruptions, highlighting the need for tailored strategies to improve CC prevention and diagnosis.</div></div>","PeriodicalId":13284,"journal":{"name":"Indian Journal of Medical Microbiology","volume":"56 ","pages":"Article 100883"},"PeriodicalIF":1.4,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144170259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}