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Prevotella buccae (P. buccae) is a gram-negative obligate anaerobe mainly associated with infections of odontogenic origin. Non-oral monomicrobial infection by these obligate anaerobic bacteria is rare. Only a few cases of monomicrobial non-oral infections by P. buccae have been reported in the literature. We are reporting a case of unilateral complicated pleural empyema in a patient with bronchial asthma infected by P. buccae. Pleural fluid aerobic culture and blood culture reports were sterile. No acid-fast bacilli were detected by Acid Fast Bacilli (AFB) staining, and cartridge-based nucleic acid assay test (CBNAAT) reports were negative for Mycobacterium tuberculosis. The isolate, P. buccae was found susceptible to Metronidazole (MIC = 3 μg/ml) and resistant to Clindamycin (MIC = 256 μg/ml). In view of rising trends of antimicrobial resistance among anaerobes, it is recommended to perform anaerobic culture and sensitivity testing in clinically suspected cases of pleuropulmonary infection for appropriate diagnosis and optimal patient management. Clindamycin should be used with caution for empiric treatment. [ABSTRACT FROM AUTHOR]

Background and Objectives: The misuse of antibiotics in recent years has led to an increase in antibiotic associated diarrheas (AAD). Out of several implicated pathogens, Clostridioides difficile is responsible for causing 15-25% of all cases of AAD. However, it has remained under diagnosed for a long time. The current study is planned to explore prevalence of C. difficile amongst AAD patients and to study clinical presentation and associated risk factors. Materials and Methods: Hospital based cross sectional study conducted in patients above 2 years of age. Diagnosis of C. difficile was done by two modalities i.e. glutamate dehydrogenase test followed by toxin detection using enzyme immunoassay and stool culture followed by toxin gene detection. Results: Twelve of 65 patients (18.4%) were positive for C. difficile. Maximum cases were found in younger age group. Abdominal pain and fever were most common complaints. 12 (18.4%) out of 65 study subjects were found to be positive by ELISA. 2/65 (3%) patients were positive for culture with presence of only tcdB gene. Ceftriaxone was the most commonly used antibiotic (25%). Conclusion: C. difficile is significant pathogen implicated in AAD with a prevalence rate of 18.4%. GDH antigen detection followed by Toxin A/B ELISA for C. difficile yielded better detection rate as compared to stool culture. [ABSTRACT FROM AUTHOR]

Quick identification and isolation of SARS-CoV-2 infected individuals is central to managing the COVID-19 pandemic. Real time reverse transcriptase PCR (rRT-PCR) is the gold standard for COVID-19 diagnosis. However, this resource-intensive and relatively lengthy technique is not ideally suited for mass testing. While pooled testing offers substantial savings in cost and time, the size of the optimum pool that offers complete concordance with results of individualized testing remains elusive. To determine the optimum pool size, we first evaluated the utility of pool testing using simulated 5-sample pools with varying proportions of positive and negative samples. We observed that 5-sample pool testing resulted in false negativity rate of 5% when the pools contained one positive sample. We then examined the diagnostic performance of 4-sample pools in the operational setting of a diagnostic laboratory using 500 consecutive samples in 125 pools. With background prevalence of 2.4%, this 4-sample pool testing showed 100% concordance with individualized testing and resulted in 66% and 59% reduction in resource and turnaround time, respectively. Since the negative predictive value of a diagnostic test varies inversely with prevalence, we re-tested the 4-sample pooling strategy using a fresh batch of 500 samples in 125 pools when the prevalence rose to 12.7% and recorded 100% concordance and reduction in cost and turnaround time by 36% and 30%, respectively. These observations led us to conclude that 4-sample pool testing offers the optimal blend of resource optimization and diagnostic performance across difference disease prevalence settings. [ABSTRACT FROM AUTHOR]

The magnitude and pace of global affliction caused by Coronavirus Disease-19 (COVID-19) is unprecedented in the recent past. From starting in a busy seafood market in the Chinese city of Wuhan, the virus has spread across the globe in less than a year, infecting over 76 million people and causing death of close to 1.7 million individuals worldwide. As no specific antiviral treatment is currently available, the major strategy in containing the pandemic is focused on early diagnosis and prompt isolation of the infected individuals. Several diagnostic modalities have emerged within a relatively short period, which can be broadly classified into molecular and immunological assays. While the former category is centered around real-time PCR, which is currently considered the gold standard of diagnosis, the latter aims to detect viral antigens or antibodies specific to the viral antigens and is yet to be recommended as a stand-alone diagnostic tool. This review aims to provide an update on the different diagnostic modalities that are currently being used in diagnostic laboratories across the world as well as the upcoming methods and challenges associated with each of them. In a rapidly evolving diagnostic landscape with several testing platforms going through various phases of development and/or regulatory clearance, it is prudent that the clinical community familiarizes itself with the nuances of different testing modalities currently being employed for this condition. [ABSTRACT FROM AUTHOR]

Purpose   Cutibacterium acnes (C. acnes) is an emerging pathogen that is highly resistant to antibiotics and is capable of causing persistent infections that are difficult to treat. Methods & Materials  Acne vulgaris patients visiting dermatology OPD of our tertiary care hospital during the study period of 2 months were recruited. Skin swabs were collected, and the sample was processed on 5% sheep-blood agar for anaerobic culture by the GasPak method. Isolates were identified by the standard biochemical test. Antimicrobial susceptibility testing was performed for clinically relevant antibiotics by the E-strip method. The clinical response was evaluated after 1-month follow-up to the prescribed antibiotics. Results  Minocycline, doxycycline, ceftriaxone, and tetracycline were the most effective antibiotics. Nonsusceptibility to clindamycin and erythromycin were observed in 11.9% and 31% isolates, respectively, with 9.5% isolates being nonsusceptible to both. For none of the antibiotics we found significant difference in the proportion of susceptible and nonsusceptible isolates between mild, moderate, and severe grades of acne vulgaris. For none of the antibiotic regimens, significant difference was observed between nonresponders and responders. Twenty-seven patients received clindamycin and among them 16 of 19 responders and 6 of 8 nonresponders yielded growth of clindamycin-susceptible isolates (p = 0.57). Conclusion  We observed significant prevalence of resistant strains of C. acnes among patients with acne vulgaris. No association was observed between in vitro susceptibility results and treatment outcome. [ABSTRACT FROM AUTHOR]

Timely diagnosis of COVID-19 infected individuals and their prompt isolation are essential for controlling the transmission of SARS-CoV-2. Though quantitative reverse transcriptase PCR (qRT-PCR) is the method of choice for COVID-19 diagnostics, the resource-intensive and time-consuming nature of the technique impairs its wide applicability in resource-constrained settings and calls for novel strategies to meet the ever-growing demand for more testing. In this context, a pooled sample testing strategy was evaluated in the setting of emerging disease outbreak in 3 central Indian districts to assess if the cost of the test and turn-around time could be reduced without compromising its diagnostic characteristics and thus lead to early containment of the outbreak. From 545 nasopharyngeal and oropharyngeal samples received from the three emerging districts, a total of 109 pools were created with 5 consecutive samples in each pool. The diagnostic performance of qRT-PCR on pooled sample was compared with that of individual samples in a blinded manner. While pooling reduced the cost of diagnosis by 68% and the laboratory processing time by 66%, 5 of the 109 pools showed discordant results when compared with induvial samples. Four pools which tested negative contained 1 positive sample and 1 pool which was positive did not show any positive sample on deconvolution. Presence of a single infected sample with Ct value of 34 or higher, in a pool of 5, was likely to be missed in pooled sample analysis. At the reported point prevalence of 4.8% in this study, the negative predictive value of qRT-PCR on pooled samples was around 96% suggesting that the adoption of this strategy as an effective screening tool for COVID-19 needs to be carefully evaluated. [ABSTRACT FROM AUTHOR]

Pyonephrosis is an uncommon condition that is associated with suppurative destruction of the renal parenchyma. Upper urinary tract obstruction by renal stones plays an important role in its aetiology. The majority of pyonephrosis is reported to be caused by aerobic bacteria but the role of anaerobes, especially black-pigmented gram-negative anaerobes, namely, Prevotella and Porphyromonas in renal infections, remain poorly defined. In view of the rarity of the event, a case of pyonephrosis by Prevotella disiens and Escherichia coli coinfection complicated by secondary peritonitis in an obstructive uropathy patient is hereby presented. An attempt is being made to review the literature on the infective aetiologies of renal abscess with special reference to anaerobes. [ABSTRACT FROM AUTHOR]

India experienced a tragic second wave after the end of March 2021, which was far more massive than the first wave and was driven by the emergence of the novel delta variant (B.1.617.2) of the SARS-CoV-2 virus. In this study, we explored the local and national landscape of the viral variants in the period immediately preceding the second wave to gain insight into the mechanism of emergence of the delta variant and thus improve our understanding of the causation of the second wave. We randomly selected 20 SARS-CoV-2 positive samples diagnosed in our lab between 3 February and 8 March 2021 and subjected them to whole genome sequencing. Nine of the 20 sequenced genomes were classified as kappa variant (B.1.617.1). The phylogenetic analysis of pan-India SARS-CoV-2 genome sequences also suggested the gradual replacement of the α variant with the kappa variant during this period. This relative consolidation of the kappa variant was significant, since it shared 3 of the 4 signature mutations (L452R, E484Q and P681R) observed in the spike protein of delta variant and thus was likely to be the precursor in its evolution. This study demonstrates the predominance of the kappa variant in the period immediately prior to the second wave and underscores its role as the "bridging variant" between the α and delta variants that drove the first and second waves of COVID-19 in India, respectively. [ABSTRACT FROM AUTHOR]

The epidemiology of dengue has been demonstrating significant changes in recent years, with rising incidence of infection in countries with known endemicity and occurrence of fresh outbreaks in previously unaffected territories. India, which has been a traditional hotspot dengue virus (DENV) transmission in the endemic south-east Asian region, has also been affected by the sweeping changes in dengue epidemiology. Two remarkable developments characterize the alterations witnessed by India 2011-2017. Firstly, all parts of the country have witnessed abrupt replacement of existing DENV lineages with emerging novel strains. Secondly, co-circulation of multiple serotypes of DENV have been reported from all across the country 2011-2017; thereby hinting at the transition of the country towards hyper-endemicity. Considering the potential clinical implications of such epidemiological transformation in terms increasing involvement of pediatric patients and growing predisposition to serious complications, the present review provides an update on the serotypic and genotypic profile of dengue outbreaks that have been witnessed by different zones of India between 2011 and 2017. Dividing the country into northern, southern, eastern, western, central and north-eastern zones, we describe discrete zone-specific distribution patterns of DENV serotypes and genotypes and observe simultaneous circulation of different DENV strains in different parts of the country. Random shifts in the genetic characteristics of the circulating strains and the widespread co- circulation of all four serotypes underscore the need for undertaking continuous and representative molecular surveillance of the circulating DENV strains across the country for prompt identification of emerging strains and novel mutants; gain insights into the formulation of Dengue vaccines and develop a clearer understanding of the molecular basis of immune evasion, disease epidemiology and pathogenesis., (Copyright © 2024 Copyright: © 2024 Journal of Vector Borne Diseases.)

Background Chikungunya is a mosquito-borne re-emerging disease that has caused a significant number of outbreaks recently in diverse geographic settings across the globe. It leads to severe debilitating illness in a significant proportion of persons who are infected. Measures to limit the impact produced by recurrent outbreaks of the disease are limited and there is an urgent clinical need for early identification of those predisposed to develop severe disease. A comprehensive understanding regarding the proportion of individuals predisposed to developing severe disease is lacking as its correlation with detectable viremia is hinted at by some studies. In this context, we hypothesized that detectable viremia reflected in the diagnostic RT-PCR assay could be significantly associated with the development of severe disease in Chikungunya among those diagnosed on the basis of seroconversion. Our study aims to confirm the same in relation to disease severity among the suspected patients of Chikungunya in the setting of a tertiary care center. Methods In a prospective observational study at a tertiary care center, a total number of 1021 Chikungunya suspects presenting within seven days of illness were screened with Chikungunya Virus IgM ELISA from 2021 to 2023. Those having positive IgM results were further tested with RT-PCR in a blinded manner. According to the information entered into the predesigned form and the hospital follow-up/discharge data, the cases where symptoms like fever and joint pain persisted beyond two weeks were classified as severe versus those resolving within two weeks as mild. The patients in each group were compared for their clinical symptoms and association with the disease severity with detectable viremia (RT-PCR positivity). Results We identified a total of 178 (17.4%) lab-confirmed Chikungunya IgM-positive cases amongst the recruited patients. Here a total of 31 (18.9%) cases could be classified as severe and 133 (74.7%) as mild illness, the remaining 14 patients were excluded from analysis due to insufficient clinical data. Severe illness was significantly higher in elderly individuals belonging to more than 60 years (p = 0.01). Viremia was detected in 16 (9%), those with detectable viremia had higher odds (OR = 4.1) of manifesting as severe disease. Among the severe cases, the proportion of cases with RT-PCR positivity (8, 25.8%) at presentation was significantly higher (P = 0.01) versus those who presented with mild disease (7, 5.5%). Conclusion Our study reveals a correlation between detectable viremia in Chikungunya virus (CHIKV) patients and an increased risk of manifesting into a severe disease, where severe cases exhibited a significantly higher proportion of viremia, indicated by RT-PCR positivity. This study hints at the presence of viremia, joint symptoms, and elderly age as potentially useful clinical predictors of disease outcomes, these may serve as indicators for closer monitoring among individuals seeking medical attention due to Chikungunya infection. However, we need to validate these findings in future longitudinal studies incorporating multiple, time-bound follow-up data on clinical outcomes, viral titers, and its long-term complications., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Rawat et al.)