ABSTRACT
Selection of reference genes in quantitative PCR is critical to determine accurate and reliable mRNA expression. Despite this knowledge, not a single study has investigated the expression stability of housekeeping genes to determine their suitability to act as reference gene in SARS-CoV-2 or Covid19 associated mucormycosis (CAM) infections. Herein, we address these gaps by investigating the expression stability of nine most commonly used housekeeping genes including TBP, CypA, B2M, 18S, PGC-1, GUSB, HPRT-1, {beta}-ACTIN and GAPDH in the patients of varying severity (asymptomatic, mild, moderate and severe). We observed significant differences in the expression of candidate genes across the disease spectrum. Next, using various statistical algorithms (delta Ct, Normfinder, Bestkeeper, RefFinder and GeNorm), we observed that CypA demonstrated the most consistent expression across the patients of varying severity and emerged as the most suitable gene in Covid19, and CAM infections. Incidentally, the most commonly used reference gene GAPDH showed maximum variations and found to be the least suitable. Lastly, comparative evaluation of expression of NRF2 is performed following normalization with GAPDH and CypA to highlight the relevance of an appropriate reference gene. Our results reinforce the idea of a selection of housekeeping genes only after validation especially during infections.
ABSTRACT
IntroductionThere is a lack of studies in adolescents with COVID-19 from developing countries. We aimed to describe the clinical profile and risk factors for severe disease in adolescents hospitalized with COVID-19. MethodsA retrospective analysis of a prospectively admitted cohort of COVID-19 patients was performed at a tertiary hospital in north India. Adolescents aged 12 to 18 years who were hospitalized during the first wave (March 2020 to December 2020) and the second wave (March 2021 to June 2021) of the pandemic were included. Data on the demographic details, clinical presentation, laboratory parameters, disease severity at admission, treatments received, and in-hospital outcomes were retrieved and logistic regression was used to identify the risk factors for occurrence of moderate or severe disease. ResultsThe study included 197 adolescents with median (IQR) age 15 (13-17) years, of whom 117 (59.4%) were male. Among these, 170 (86.3%) were admitted during the 1st wave. Underlying comorbidities were present in 9 (4.6%) patients. At the time of hospital admission, 60 (30.9%) patients were asymptomatic. In the severity grading, 148 (84.6%) had mild, 16 (9.1%) had moderate, and 11 (6.3%) had severe disease. Fever (14.9%) and cough (14.9%) were the most commonly encountered symptoms. The median (IQR) duration of hospital stay was 10 (8-13) days and 6 (3.1%) patients died in hospital. The odds of moderate to severe disease were 3.8 for second wave, 1.9 for fever and 1.1 for raised C reactive protein (CRP). ConclusionIn our single-center study from northern India, adolescents admitted with COVID-19 had predominantly asymptomatic or mild disease. Admission during the second wave of COVID-19 pandemic, presence of fever and raised CRP were risk factors for moderate or severe disease. Lay SummaryFrom 3rd January 2022 onwards, adolescents between 15 to 18 years of age in India will be given Covaxin vaccine, as per the latest Indian government guidelines. In our study, we aimed to describe the clinical profile and risk factors for severe disease in adolescents hospitalized with COVID-19. Our study included 197 adolescents. 170 (86.3%) of them were admitted during the 1st wave and the rest 27 (13.7%) during the 2nd wave. At the time of hospital admission, 60 (30.9%) patients were asymptomatic. In the severity grading, 148 (84.6%) had mild, 16 (9.1%) had moderate, and 11 (6.3%) had severe disease. Fever (14.9%) and cough (14.9%) were the most commonly encountered symptoms. The median (IQR) duration of hospital stay was 10 (8-13) days and 6 (3.1%) patients died in hospital. 2nd wave, fever and high C reactive protein increased the odds of moderate to severe disease.
ABSTRACT
BackgroundThe SARS-CoV-2 pandemic has quickly become an unprecedented global health threat. India with its unique challenges in fighting this pandemic, imposed one of the worlds strictest and largest population-wide lockdown on 25 March 2020. Here, we estimated key epidemiological parameters and evaluated the effect of control measures on the COVID-19 epidemic in India. Through a modelling approach, we explored various strategies to exit the lockdown. MethodsWe obtained data from 140 confirmed COVID-19 patients at a tertiary care hospital in India to estimate the delay from symptom onset to confirmation and the proportion of cases without symptoms. We estimated the basic reproduction number (R0) and time-varying effective reproduction number (Rt) after adjusting for imported cases and reporting lag, using incidence data from 4 March to 25 April 2020 for India. We built upon the SEIR model to account for underreporting, reporting delays, and varying asymptomatic proportion and infectivity. Using this model, we simulated lockdown relaxation under various scenarios to evaluate its effect on the second wave, and also modelled increased detection through testing. We hypothesised that increased testing after lockdown relaxation will decrease the epidemic growth enough to allow for greater resumption of normal social mixing thus minimising the social and economic fallout. ResultsThe median delay from symptom onset to confirmation (reporting lag) was estimated to be 2{middle dot}68 days (95%CI 2{middle dot}00-3{middle dot}00) with an IQR of 2{middle dot}03 days (95%CI 1{middle dot}00-3{middle dot}00). 60{middle dot}7% of confirmed COVID-19 cases (n=140) were found to be asymptomatic. The R0 for India was estimated to be 2{middle dot}083 (95%CI 2{middle dot}044-2{middle dot}122; R2 = 0{middle dot}972), while the Rt gradually down trended from 1{middle dot}665 (95%CI 1{middle dot}539-1{middle dot}789) on 30 March to 1{middle dot}159 (95%CI 1{middle dot}128-1{middle dot}189) on 22 April. In the modelling, we observed that the time lag from date of lockdown relaxation to start of second wave increases as lockdown is extended farther after the first wave peak. This benefit was greater for a gradual relaxation as compared to a sudden lifting of lockdown. We found that increased detection through testing decreases the number of total infections and symptomatic cases, and the benefit of detecting each extra case was higher when prevailing transmission rates were higher (as when restrictions are relaxed). Lower levels of social restrictions when coupled with increased testing, could achieve similar outcomes as an aggressive social distancing regime where testing was not increased. ConclusionsThe aggressive control measures in India since 25 March have produced measurable reductions in transmission, although suppression needs to be maintained to achieve sub-threshold Rt. Additional benefits for mitigating the second wave can be achieved if lockdown can be feasibly extended farther after the peak of active cases has passed. Aggressive measures like lockdowns may inherently be enough to suppress the epidemic, however other measures need to be scaled up as lockdowns are relaxed. Expanded testing is expected to play a pivotal role in the lockdown exit strategy and will determine the degree of return to normalcy that will be possible. Increased testing coverage will also ensure rapid feedback from surveillance systems regarding any resurgence in cases, so that geo-temporally targeted measures can be instituted at the earliest. Considering that asymptomatics play an undeniable role in transmission of COVID-19, it may be prudent to reduce the dependence on presence of symptoms for implementing control strategies, behavioral changes and testing.
ABSTRACT
Few studies have tried to assess prognostic variables in chronic obstructive pulmonary disease (COPD) patients requiring mechanical ventilation (MV). We evaluated serum C reactive protein, (CRP) pre-albumin (PA) and transferrin (TR) levels in AE-COPD patients requiring MV as prognostic markers of in hospital mortality. 93 AE-COPD patients on MV were evaluated. Detailed clinical evaluation was done daily. Serum CRP & PA were measured on admission, 3rd, 8th and 16th day; TR was measured on admission, 8th and 16th day. Demographics, baseline parameters, CRP, PA and TR were correlated with mortality. Of 93 patients, 49 (52.69%) survived whereas 44 patients (47.31%) died. APACHE II, serum urea & albumin were similar in survivors & non-survivors. Baseline CRP (≥10.5 mg/dl) had sensitivity of 60.5%, specificity of 60.2%, with area under curve (AUC) of 0.62 as predictor of mortality. CRP (≥7 mg/dl) on day 3 had sensitivity (65.5%) and specificity (63.3%) with AUC 0.70 as predictor of mortality. Baseline serum prealbumin was 11.00 (0.09-29.26) mg/dl, and similar in survivors & non-survivors (p = 0.7). Prealbumin at day 8 (n = 50) < 13.5 mg/dl had sensitivity 54.6%, and specificity 51.4% with AUC 0.54 (95% CI 0.34-0.75) as predictor of mortality. Transferrin at day 8 (n = 50) of <148.9 had sensitivity 63.4% and specificity 61.4% with AUC 0.61 with respect to mortality. High CRP levels at baseline, persistently elevated CRP (on day 3) may predict mortality in AE-COPD patients requiring MV. Further studies are required to establish prognostic variables in this patient population.
