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Cytomegalovirus (CMV) is one of the most common post-transplant viral infections causing significant morbidity and occasional mortality. Limited literature on the potential role of pre-transplant CMV-specific cell-mediated immunity (CMV-CMI) is available. This study aimed to evaluate the clinical utility of pre-transplant CMV-CMI monitoring in the occurrence of post-transplant CMV infection.This was a prospective, observational study where all adult CMV seropositive patients undergoing living donor liver transplantation at a tertiary care institute were enrolled. CMV-CMI was measured using QuantiFERON-CMV (Qiagen GmbH, Hilden, Germany) and interpreted as positive if the value was ≥0.2 IU/ml, 1-2 days prior to the transplant. Based on pre-transplant CMV-CMI, cases were classified into Group 1 (n = 13, 43.3%) (positive) and Group 2 (n = 17, 56.7%) (negative). CMV infection was defined as the detection of CMV-DNA2.7 logThe mean age was 43 years with male (n = 29, 96.9%) predominance. Overall 40% of recipients developed post-transplant CMV infection, two (15.4%) in group 1 and 10 (58.8%) in group 2 (p-value = 0.016). Recipients in group 2 had 87% higher odds (odds ratio 0.13, confidence interval [CI] 95) of developing post-transplant CMV infection compared to group 1. The overall median duration of occurrence of post-transplant CMV infection was 26 days with the median viral load being 2.8 logPre-transplant CMV-CMI may play a protective role against post-transplant CMV infection and can serve as an adjunct for pre-transplant risk stratification.

Background and Objectives: Timely diagnosis is essential for the containment of the disease and breaks in the chain of transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The present situation demands the countries to scale up their testing and design innovative strategies to conserve diagnostic kits and reagents. The pooling of samples saves time, workforce and most importantly diagnostic kits and reagents. In the present study, we tried to define the pool size that could be applied with acceptable confidence for testing. Materials and Methods: We used repeatedly tested positive clinical sample elutes having different levels of SARS CoV 2 RNA and negative sample elutes to prepare seven series of 11 pools each, having pool sizes ranging from 2 to 48 samples to estimate the optimal pool size. Each pool had one positive sample elute in different compositions. All the pools were tested by SARS CoV 2 reverse transcriptase quantitative polymerase chain reaction. Results: Out of the 77 pools, only 53 (68.8%) were found positive. The sensitivity of pools of 2–48 samples was decreased from 100% (95% confidence interval [CL]; 98.4–100) to 41.41% (95% CL; 34.9–48.1). The maximum size of the pool with acceptable sensitivity (>95%) was found to be of six samples. For the pool size of six samples, the sensitivity was 97.8% and the efficiency of pooling was 0.38. Conclusions: The pooling of samples is a practical way for scaling up testing and ultimately containing the further spread of the CoV disease 2019 pandemic.

IntroductionTimely diagnosis is essential for the containment of the disease and breaks in the chain of transmission of SARS-CoV-2. The present situation demands countries to scale up their testing and design innovative strategies to conserve diagnostic kits and reagents. The pooling of samples saves time, manpower, and most importantly diagnostic kits and reagents. In the present study, we tried to define the pool size that could be applied with acceptable confidence for testing.Material and methodsWe used repeatedly tested positive clinical sample elutes having different levels of SARS CoV 2 RNA and negative sample elutes to prepare seven series of 11 pools each, having pool sizes ranging from 2 to 48 samples to estimate the optimal pool size. Each pool had one positive sample elute in different compositions. All the pools were tested by SARS CoV 2 RT-qPCR.ResultsOut of the 77 pools, only 53 (68.8%) were found positive. The sensitivity of pools of 2 to 48 samples was decreased from 100% (95% CL; 98.4-100) to 41.41% (95% CL; 34.9-48.1). The maximum size of the pool with acceptable sensitivity (>95%) was found to be of 6 samples. For the pool size of 6 samples, the sensitivity was 97.8% and the efficiency of pooling was 0.38.ConclusionThe pooling of samples is a practical way for scaling up testing and ultimately containing the further spread of the COVID-19 pandemic.

IntroductionEstimation of hepatitis B (HBV) viral load (VL) is critical in hepatitis-B cascade-of-care and currently there is no point of care (POC) molecular assay available for that. This study evaluated the performance of a new near point of care molecular assay Xpert HBV-VL assay against FDA approved Real time PCR assays.Materials & methodsIn this retrospective study 119 archived plasma samples from HBV infected patients, and 53 hepatitis B surface antigen (HBsAg) patients were simultaneously tested for HBV DNA quantification on 2 real time PCR conventional assays and Xpert assay. The routine method for reporting to patient was Abbott Real Time PCR.ResultsThe range of HBV DNA load in samples was 1 to 8.76 log10IU/ml with a median load of 4.46 (IQR: 1-8.76) log10IU/ml as detected by routine assay (Abbott Real-Time HBV VL assay). Genotyping could be done in 95 (79.8%) samples and genotype D (83; 87.37%) was found commonest. The Xpert assay demonstrated good correlation with Abbott (R2= 0.944) and Roche (R2= 0.963). On comparison the mean difference (95% Confidence Interval) in average viral load was −0.018 log10 IU/ml and −0.043 log10 IU/ml when Xpert was compared with the Abbott and Roche assay, respectively. The overall sensitivity, specificity, negative predictive value and positive predictive value of the Xpert assay was found 97.5%, 100%, 94.65 & 100% respectively.ConclusionXpert HBV-VL assay which has a potential for near point of care molecular testing has shown excellent performance and found to be a reliable method for HBV DNA quantification.

BackgroundCorona virus disease 2019 (COVID-19) which initially started as a cluster of pneumonia cases in the Wuhan city of China has now become a full blown pandemic. Timely diagnosis of COVID-19 is the key in containing the pandemic and breaking the chain of transmission. In low and middle income countries availability of testing kits has become the major bottle neck in testing. Novel methods like pooling of samples are the need of the hour.MethodExtracted RNA samples were randomly placed in pools of 8 on a 96 well plate. Both individual RNA (ID) and pooled RNA RT-qPCR for the screening E gene were done in the same plate and the positivity for the E gene was seen.ResultsThe present study demonstrated that pool testing with 8 RNA samples can easily detect even up to a single positive sample with Ct value as high as 38. The present study also showed that the results of pool testing is not affected by number of positive samples in a pool.ConclusionPooling of 8 RNA samples can reduce the time and expense by one eighth, and can help expand diagnostic capabilities, especially during constrained supply of reagents and PCR kits for the diagnosis of SARS-CoV-2 infection.

Introduction Estimation of hepatitis B (HBV) viral load (VL) is critical in hepatitis-B cascade-of-care and at present there is no point of care (POC) molecular assay available for the same. This study evaluated the performance of a new near point of care molecular assay Xpert HBV- VL assay against the approved assays. Materials & methods In this study 172 archived previously tested samples, were simultaneously re-tested for HBV DNA on 3 real-time PCR assays: Abbott Real-Time HBV, Roche TaqMan® HBV and Xpert HBV assay. Results Out of 172 samples, 119 were previously positive for HBV DNA with a median VL 4.46 (IQR: 1–8.76)log10IU/mL and 53 were HBV DNA negative. Genotyping could be done in 95 (79.8 %) samples and genotype D (83; 87.3 %) was the commonest type. The Xpert assay demonstrated a good correlation with Abbott (R2 = 0.94) and Roche (R2 = 0.96). On comparison, the mean difference with 95 % Confidence Interval of Xpert assay was −0.018 and −0.043 log10 IU/mL with Abbott and Roche assay, respectively. The overall sensitivity, specificity, negative predictive value, and positive predictive value of the Xpert assay was found 97.5 %, 100 %, 94.65 & 100 % respectively. Conclusion Xpert HBV-VL assay which has a potential for near point of care molecular testing has shown excellent performance and found to be a reliable method for HBV DNA quantification.