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Objective:To explore the expressions of multiple inflammation markers in the patients with COVID-19 and their clinical values, and to provide theoretical basis for clinical diagnosis and treatment.Methods:A total of 164 patients, diagnosed with COVID-19 and admitted to Guangzhou Eighth People′s Hospital from January to February 2020, were selected as the research group and divided into three groups (ordinary, severe, and critically severe pneumonia) according to the disease severity. Meanwhile 66 non-infected patients during the same period were selected as negative control group. The expressions of white blood cell (WBC), lymphocyte (LYM), C-reactive protein (CRP), serum amyloid A protein (SAA), and procalcitonin (PCT) were retrospective studied and compared between groups. The diagnostic values of WBC, CRP, SAA and the combination of these three markers in all patients with COVID-19 and in different severity groups were analyzed by receiver operator characteristic (ROC) curve.Results:Compared with control group [WBC count:8.13(6.51,9.42)×10 9/L, LYM count:2.00(1.28,2.43)×10 9/L], WBC count [4.94(4.05, 6.67) ×10 9/L] and LYM count [1.33(0.94, 1.96) ×10 9/L] of COVID-19 patients were significantly reduced ( Z=-7.435, P<0.01; Z=-4.906, P<0.01) . Compared with the control group [CRP: 1.36 (0.57~5.67) mg/ml; SAA:4.98 (4.80-15.75) mg/ml], CRP [7.93 (2.45-23.98) mg/ml] and SAA [34.13 (4.83-198.40) mg/ml] were increased in research group ( Z=-5.72, P<0.01; Z=-4.166, P<0.01) . PCT in the control group and the research group were 0.100 0(0.030 6-0.100 0)ng/ml and 0.044 5(0.031 6-0.077 0)ng/ml, respectively. There was no statistical difference between two groups ( Z=-1.451, P=0.147) . The areas under the receiver operator characteristic curve (AUC) of WBC, CRP and SAA in patients with COVID-19 were 0.814, 0.742, 0.673, respectively ( P<0.01), while the AUC of the combination of three indexes for COVID-19 diagnosis was 0.882, with 83.33%(55/66) specificity and 84.76% (139/164) sensitivity, P<0.01.The AUCs of WBC, CRP, and SAA for predicting severe and critically severe COVID-19 were 0.799, 0.779, and 0.886, respectively ( P<0.01).The AUC of the combination of three indexes for the diagnosis of severe and critically severe COVID-19 was 0.924, with 78.67% (118/150) specificity and 14/14 sensitivity ( P<0.01). Conclusion:Combining detection of WBC, CRP and SAA can improve the specificity and sensitivity of COVID-19 diagnosis, with a high diagnostic value for severe and critically severe COVID-19.
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Objective:To evaluate the performance of three antibody kits for novel coronavirus (SARS-CoV-2) and to investigate the feasibility and advantages of them in clinical application.Methods:A total of 104 patients who were admitted to Guangzhou Eighth People′s Hospital with COVID-19 from January to February 2020 were selected as research group. Fifty-one healthy subjects were selected during the same period as negative control group. Serum antibodies (IgM/IgG) against SARS-CoV-2 were detected using two kinds of colloidal gold kits (A and B kits) and one chemiluminescence kit (C kit). The positive rates of SARS-CoV-2 nucleic acid in different samples from patients with COVID-19 were retrospectively analyzed.Results:The clinical sensitivity of A kit to detect SARS-CoV-2-specific IgM and IgG was 77.88% (81/104) and 65.38% (68/104), respectively, and the clinical specificity was 70.59% (36/51) and 100.00% (51/51). However, the false positive rate in IgM detection was as high as 29.41% (15/51). The sensitivity of B kit to test total antibodies to SARS-CoV-2 was 63.46% (66/104), and the clinical specificity was 94.12% (48/51). The clinical sensitivity of C kit to detect SARS-CoV-2-specific IgM and IgG were respectively 31.73% (33/104) and 64.42% (67/104), and the clinical specificity were both 98.04% (50/51). There was a moderate correlation between the detection results of two colloidal gold kits and the chemiluminescence kit with the Kappa values of 0.462 and 0.587 ( Z=6.157, P<0.01; Z=7.345, P<0.01). C kit had the highest positive detection rate for IgG, and would be more reliable to be used for IgG detection in COVID-19 patients 14 d after onset. The total positive detection rate of nucleic acid in all types of samples was 63.46% (66/104). The highest positive detection rate was in throat swabs or sputum samples, followed by those in blood samples and anal swabs. No viral nucleic acid was detected in urine samples for the time being. Conclusions:SARS-CoV-2-specific antibodies could be detected in the early or late stage of COVID-19. The method of antibody detection has the advantages of shorter detection time, simple operation and high biological safety, indicating that it could be used as a supplementary or auxiliary detection for the diagnosis of suspected COVID-19 cases with negative nucleic acid test results. The chemiluminescence kit has good sensitivity and specificity, and is well recommended for clinical laboratories.
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Objective@#To explore the Expressions of multiple inflammation markers in the patients with 2019 novel coronavirus pneumonia (COVID-19) and their clinical values, and to provide theoretical basis for clinical diagnosis and treatment.@*Methods@#A total of 164 patients, diagnosed with COVID-19 and admitted to Guangzhou Eighth People's Hospital from January to February 2020, were selected as the research group and divided into three groups (ordinary, severe, and critically severe pneumonia) according to the disease severity. Meandwhile 66 non-infected patients during the same period were selected as negative control group. The expressions of WBC, LYM, CRP, SAA, and PCT were retrospective studied and compared between groups. The diagnostic values of WBC, CRP, SAA and the combination of these three markers in all patients with COVID-19 and in different severity groups were analyzed by ROC curve.@*Results@#Compared with control group (WBC count :8.13(6.51,9.42)×109/L, LYM count:2.00(1.28,2.43)×109/L), WBC count [4.94(4.05, 6.67) ×109/L] and LYM count [1.33(0.94, 1.96) ×109/L] of COVID-19 patients were significantly reduced (Z=-7.435, P<0.01; Z=-4.906, P<0.01) . Compared with the control group [CRP: 1.36 (0.57~5.67) mg/ml; SAA:[4.98 (4.80~15.75) mg/mL], CRP [7.93 (2.45~23.98) mg/ml] and SAA [34.13 (4.83~198.40) mg/ml] were increased in research group (Z=-5.72, P<0.01; Z=-4.166, P<0.01) . PCT in the control group and the research group were 0.100 0(0.030 6~0.100 0)ng/ml and 0.044 5(0.031 6~0.077 0)ng/ml, respectively. There was no statistical difference between two groups (Z=-1.451, P=0.147) . The areas under the ROC curve (AUC) of WBC, CRP and SAA in patients with COVID-19 were 0.814, 0.742, 0.673, respectively (P<0.01), while the AUC of the combination of three indexes for COVID-19 diagnosis was 0.882, with 83.33%(55/66) specificity and 84.76% (139/164) sensitivity, P<0.01.The AUCs of WBC, CRP, and SAA for predicting severe and critically severe COVID-19 were 0.799, 0.779, and 0.886 , respectively (P<0.01), and the AUC of the combination of three indexes for the diagnosis of severe and critically severe COVID-19 was 0.924, with 78.67% (118/150) specificity and 14/14 sensitivity (P<0.01).@*Conclusion@#Combining detection of WBC, CRP and SAA can improve the specificity and sensitivity of COVID-19 diagnosis, with a high diagnostic value for severe and critically severe COVID-19.
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Objective To investigate the role and the mechanism of ppk1 gene (coding for polyphosphate kinase 1) in oxidative stress resistance in uropathogenic Escherichia coli (UPEC).MethodsMutant strains with ppk1-deletion (△pk1) and complemented strains (△pk1-C) were constructed based on the UPEC strain CFT073.A comparative analysis was conducted to analyze survival rates of CFT073, △pk1 and △pk1-C strains at different time points while they were under oxidative stress.Differences in protein expression between CFT073 and △pk1 strains were analyzed using mass spectrometric analysis.Differences between CFT073 and △pk1 strains in expression of katG and katE genes were analyzed using real-time quantitative RT-PCR.Results The survival rate of △pk1 strains was lower than that of CFT073 strains at every time point, while the survival rate of △pk1-C strains was basically the same as that of CFT073 strains.Gel image analysis and mass spectrometric analysis revealed that six proteins were down-regulated and one was up-regulated in △pk1 strains as compared with those in CFT073 strains.Expression of the catalase-coding genes katG and katE in △pk1 strains were respectively (20.5±8.2)% and (20.9±6.9)% of those in CFT073 strains (P<0.05).Conclusion The ppk1 gene plays an important role in oxidative stress resistance in UPEC by modulating the expression of catalase-coding genes katG and katE.