Association between serum albumin levels and disease severity in adult patients with dengue: A 7-year retrospective cohort study in China's Mainland

Objective:To identify the association between serum albumin levels and disease severity among adult patients with dengue in China's Mainland.Methods:This retrospective cohort study analyzed the data of adult patients(aged≥18 years)hospitalized with laboratory-confirmed dengue in a tertiary center for infectious diseases from 2013 to 2019 in China's Mainland.Serum albumin levels were estimated and compared between patients with severe dengue and non-severe dengue.Additionally,the association between serum albumin levels and severe dengue was evaluated using a generalized linear model[relative risks(RR)].Multivariate logistic regression analysis was performed to identify the potential predictors of severe dengue.Results:Overall,1568 patients were included in this study.Of these patients,34(2.17%)developed severe dengue.The median serum albumin levels were significantly lower in patients with severe dengue than that in those with non-severe dengue(33 g/L vs.37 g/L,P<0.001).After adjustment for age,sex,and comorbidities,hypoalbuminemia(RR 4.877,95%CI 2.193-11.461,P<0.001)was found to be a predictor of severe dengue.Serum albumin levels(OR 1.303,95%CI 1.161-1.462,P<0.001)and age(OR 1.038,95%CI 1.017-1.061,P<0.001)were significant risk factors for severe dengue.The area under the curve for serum albumin levels to distinguish severe dengue was 0.787.Conclusions:Lower serum albumin levels were significantly associated with disease severity in adult patients with dengue.Hypoalbuminemia on admission resulted in at least a four-fold increased risk of severe dengue.

Discrimination of False Negative Results in RT-PCR Detection of SARS-CoV-2 RNAs in Clinical Specimens by Using an Internal Reference

Reverse transcription-polymerase chain reaction(RT-PCR)is an essential method for specific diagnosis of SARS-CoV-2 infection.Unfortunately,false negative test results are often reported.In this study,we attempted to determine the principal causes leading to false negative results of RT-PCR detection of SARS-CoV-2 RNAs in respiratory tract specimens.Multiple sputum and throat swab specimens from 161 confirmed COVID-19 patients were tested with a commercialfluorescent RT-PCR kit targeting the ORF1 ab and N regions of SARS-CoV-2 genome.The RNA level of a cellular housekeeping gene ribonuclease P/MRP subunit p30(RPP30)in these specimens was also assessed by RT-PCR.Data for a total of 1052 samples were retrospectively re-analyzed and a strong association between positive results in SARS-CoV-2 RNA tests and high level of RPP30 RNA in respiratory tract specimens was revealed.By using the ROC-AUC analysis,we identified Ct cutoff values for RPP30 RT-PCR which predicted false negative results for SARS-CoV-2 RT-PCR with high sensitivity(95.03%–95.26%)and specificity(83.72%–98.55%)for respective combination of specimen type and ampli-fication reaction.Using these Ct cutoff values,false negative results could be reliably identified.Therefore,the presence of cellular materials,likely infected host cells,are essential for correct SARS-CoV-2 RNA detection by RT-PCR in patient specimens.RPP30 could serve as an indicator for cellular content,or a surrogate indicator for specimen quality.In addition,our results demonstrated that false negativity accounted for a vast majority of contradicting results in SARS-CoV-2 RNA test by RT-PCR.

CORRECTION:Correction to:Discrimination of False Negative Results in RT-PCR Detection of SARS-CoV-2 RNAs in Clinical Specimens by Using an Internal Reference

In the original version of Fig.41 and 4J,the cutoff lines were accidently shifted during figure layout.Figures 41 and 4J are re-drawn and provided below.