Indian Journal of Medical Microbiology最新文献

Purpose

Due to the potential for Aspergillus species to cause lethal infections and the rising rates of antifungal resistance, the significance of antifungal susceptibility tests has increased. We aimed to assess the sensitivities of Aspergillus species to amphotericin B (AMB), voriconazole (VOR), itraconazole (ITZ), and caspofungin (CAS) using disk diffusion (DD) and gradient diffusion (GD) methods and compare them with broth microdilution (BMD) as the reference susceptibility method.

Methods

The study involved 62 Aspergillus fumigatus, 28 Aspergillus flavus, and 16 Aspergillus terreus isolates, totaling 106 Aspergillus isolates. BMD and DD methods were performed in accordance with CLSI M38-A2 and CLSI M51-A documents, respectively. The GD method utilized nonsupplemented Mueller Hinton agar (MHA) as the medium.

Results

In the BMD method, the lowest minimal inhibitory concentration (MIC)₉₀ or minimal effective concentration (MEC)₉₀ values were observed for VOR and CAS (0.5 μg/mL and 0.06 μg/mL, respectively). AMB and ITZ MIC₉₀ values were both 2 μg/mL. In our comparison of the GD method with the BMD method at ±2 dilution, we observed essential agreement rates of 91.6%, 99.1%, 100%, and 38.6% for AMB, VOR, ITZ, and CAS, respectively. When comparing DD and BMD methods, we found categorical agreement rates of 65.1%, 99.1%, 77.3%, and 100% for AMB, VOR, ITZ, and CAS, respectively. For GD and BMD methods, these rates were 79.2%, 99.1%, 87.8%, and 100%.

Conclusions

Given the high essential and categorical agreement rates, we posit that the GD method is a viable alternative to the BMD method for AMB, ITZ and VOR but not for CAS. In addition, the use of nonsupplemented MHA in the GD method proves advantageous due to its cost-effectiveness and widespread availability compared to other growth media.

Purpose

Palghar district, located in the coastal region of the Konkan division of Maharashtra, has a predominantly tribal population. Leptospirosis is a major neglected public health problem and is highly underreported in Palghar district. The study aimed to evaluate the seropositivity of Leptospira infection and its associated epidemiological factors in tribal areas of the Palghar district of Maharashtra.

Methods

The present retrospective study included 94 samples of patients clinically suspected of leptospirosis during a period of one year (2021–2022) tested at Model Rural Health Research Unit (MRHRU) Dahanu. The serum sample testing was done for the presence of specific Leptospira IgM antibodies using the Panbio™ Leptospira IgM ELISA kit. Leptospirosis seropositivity was correlated with various epidemiological risk factors.

Results

A total of 12 samples of patients tested positive for specific IgM antibodies by ELISA method, indicating an overall positivity of 12.8%. Among those who tested positive, fever (83.3%), headache (58.3%), myalgia (50%), redness of the eyes (50%), and calf tenderness (16.7%) were the common symptoms observed. Subjects with redness of the eyes were significantly associated with leptospirosis (p = 0.018). The highest positivity (50%) was reported from the Ganjad area of Dahanu taluka. Farmers and animal handlers were most affected by leptospirosis.

Conclusion

The high proportion of Leptospirosis cases reflects the endemic nature of the disease in the Palghar district. This study shows seasonal trends in leptospirosis incidence over the year. The clinical presentation of leptospirosis may vary from sub-clinical to mild illness to severe and potentially fatal. The findings of this study will be important for achieving the overarching goal of One Health.

Introduction

Candida auris is emerging as an important cause of candidemia and deep seated candidal infection. We compared the susceptibility results of bloodstream Candida auris isolates by Vitek 2 with Sensititre YeastOne (SYO) method.

Methods

Forty-seven C. auris blood stream isolates were simultaneously tested for AFST by Vitek 2 and SYO.

Results

All strains were resistant to Fluconazole. 25.5% isolates showed pan-azole resistance. In comparison with SYO, lower MICs for voriconazole were noted with Vitek 2 (VME rate 76.1%). All strains were sensitive to anidulafungin and micafungin by SYO. For micafungin, Vitek 2 demonstrated higher MICs and an ME rate of 23.5%. Susceptibility interpretation of caspofungin by SYO was challenged by development of ‘Eagle effect’ resulting in sensitivity of 28.2%. We studied the evolution of caspofungin ‘Eagle effect’ with SYO by serial hourly MIC readings and noted that paradoxical growth commenced at 21 hrs of incubation. Compared to SYO, Vitek 2 showed higher resistance rate to Amphotericin B with ME rate of 25.6%.

Conclusion

Laboratories using commercial AFST systems for Candida auris need to be aware of the possibility of ME and VME for amphotericin B and voriconazole respectively with Vitek 2 and ‘Eagle effect’ for caspofungin with SYO.

Background

Throughout the COVID-19 pandemic, virus evolution and large-scale vaccination programs have caused multiple exposures to SARS CoV-2 spike protein, resulting in complex antibody profiles. The binding of these to spike protein of “future” variants in the context of such heterogeneous exposure has not been studied.

Methods

We tested archival sera (Delta and Omicron period) stratified by anti-spike antibody (including IgG) levels for reactivity to Omicron-subvariants(BA.1, BA.2,BA.2.12.1, BA.2.75, BA.4/5 and BF.7) spike protein. Assessed antigenic distance between groups using Antigenic Cartography and performed hierarchical clustering of antibody data in a Euclidean distance framework.

Results

Antibody (including IgG) antibody reactivity to Wild-type (CLIA) and subvariants (ELISA) spike protein were similar between periods (p > 0.05). Both 'High S′ and ‘Low S’ of Delta and Omicron periods were closely related to “future” subvariants by Antigenic Cartography. Sera from different S groups clustered together with ‘Low S’ interspersed between ‘High S’ on hierarchical clustering, suggesting common binding sites. Further, anti-spike antibodies (including IgG) to Wild-type (S1/S2 and Trimeric S) clustered with Omicron-subvariant binding antibodies.

Conclusions

Hybrid immunity caused by cumulative virus exposure in Delta or Omicron periods resulted in equivalent binding to “future” variants, which might be due to binding to conserved regions of spike protein of future variants. A prominent finding is that the ‘Low S’ antibody demonstrates similar binding.

Rhodococcus hoagii is a gram positive actinomycete found in horses and cattle. Humans can be infected by ingestion or inhalation through contaminated food or soil. The organism usually infects immunosuppressed hosts with pneumonia being the common presentation. We present a case of an 89 years old, apparently immunocompetent host presenting with fever, encephalopathy and arthritis who grew Rhodococcus hoagii in blood and synovial fluid, The patient responded well to a combination of vancomycin, azithromycin and imipenem-cilastatin. Our case demonstrates that extra-pulmonary manifestations such as septic arthritis and bacteremia can be seen in immune competent hosts.

Background

Research is essential for the advancement of science, technology and development. Research requires funding and resource allocation. And funding requires the ability to write research grant application. This skill is acquired by the researchers and investigators while in the job with the help of colleagues. In the competitive world of academic research in college, universities, research bodies and other academic institutions it is essential to have excellent research grant application writing capabilities. This enhances the institution's and the individual's opportunities to conduct meaningful research, especially those which are resource intensive. Although research methodology is taught in the post-graduate curriculum not much training is available regarding research grant writing.

Objective

In this article a broad outline has been provided about how research grant applications may be written. The objective is to provide young investigators with a framework upon which they can develop their research grant applications.

Content

A good research grant application generally facilitates research by providing the essential foundation necessary for the investigators to proceed in their research with clarity and less ambiguity. The current article discusses the landscape review of research grant applications, details of research grant organizations, research grant writing guidance and research grant writing format. The research application should include aims and objectives of the research, details of preliminary work, novelty and translational value, materials and methods (including standard operating procedure), research budget, details of investigators referees, mentor, Gantt chart, approvals and permission, facilities available. As research activities are essential for growth and development of any subject it is important that institutions focus on this important skill for students and academicians.

Here, we report the genomic characterization of a pan drug-resistant (PDR) enteroaggregative Escherichia coli (EAEC) isolated from an immunocompromised infant who had diarrhea. The isolate belonged to the sequence type (ST) 38, which is a known enteroaggregative Escherichia coli (EAEC)/uropathogenic Escherichia coli (UPEC) hybrid strain having multi-drug resistance (MDR). The strain carried genes encoding multiple resistances to carbapenems, third-generation cephalosporins, polymyxin, fluoroquinolones, aminoglycosides, fosfomycin, nitrofurantoin, sulphonamides, and multiple efflux pump genes. Interspecies horizontal transfer, inter-strain, and clonal spread of these resistances to commensals and pathogens will be worrisome. We are concerned about the spread of such PDR strains. The genomic characterization of such strains will be useful in understanding the genetic makeup of EAEC/UPEC hybrid strains and developing new vaccines/diagnostics and therapeutics.

Purpose

The study explores the impact of significant interpretative breakpoint changes for aminoglycosides and piperacillin-tazobactam in Enterobacterales and Pseudomonas aeruginosa, considering PK/PD, clinical data, and susceptibility on clinical reporting and use.

Procedure

Between January 2021 and June 2023, a total of 189,583 samples were processed for bacterial pathogens and antimicrobial susceptibility testing was performed using disc diffusion method/VITEK® 2 Compact system/broth microdilution. WHONET software was utilised to capture and analyse the changes in the interpretation of disc diffusion method, following updates to CLSI M100 documents in comparison to previous editions. Antimicrobial consumption data was collected and interpreted as DDD/100 bed days using AMC tool software. Here, we present data for 13,615 members of Order Enterobacterales and 1793 Pseudomonas aeruginosa isolates.

Finding

Enterobacterales exhibited a significant susceptibility drop of 14.7% for gentamicin and 21.7% for amikacin. Pseudomonas aeruginosa showed an increase in isolates with intermediate tobramycin susceptibility, from 0.6% to 29.7%, with relatively minor changes in piperacillin-tazobactam interpretation.

Conclusion

The changes indicate a shift toward increased 'resistance' and 'intermediate susceptibility' for these antibiotics, emphasizing the need for cautious use and leveraging PK/PD knowledge for improved antibiotic utilization, patient outcomes, and antimicrobial stewardship.

Food borne infections pose significant public health problem, especially in developing countries of the world. A continuous surveillance to ensure the health of the personnel involved in preparation of the hospital food is important as they can be a source of spreading the infections and possible outbreaks. We analysed the data of the prevalence of intestinal parasitic infections in food handlers in our tertiary care centre from 2018 to 2022 and 6.8% were observed to harbour intestinal parasites during the period. This signifies the importance of routine screening, and the need of awareness and education of the food handlers in hospitals.