Dynamic changes of D-Dimer and Neutrophil-Lymphocyte Count Ratio as prognostic biomarkers in COVID-19 (preprint)

Background: Since December 2019, the outbreak of COVID-19 caused a large number of hospital admissions in China. Many patients with COVID-19 have symptoms of acute respiratory distress syndrome, even are in danger of death. This is the first study to evaluate dynamic changes of D-Dimer and Neutrophil-Lymphocyte Count Ratio (NLR) as a prognostic utility in patients with COVID-19 for clinical use. Methods In a retrospective study, we collected data from 349 hospitalized patients who diagnosed as the infection of the COVID-19 in Wuhan Pulmonary Hospital. We used ROC curves and Cox regression analysis to explore critical value (optimal cut-off point associated with Youden index) and prognostic role of dynamic changes of D-Dimer and NLR. Results 349 participants were enrolled in this study and the mortality rate of the patients with laboratory diagnosed COVID-19 was 14.9%. The initial and peak value of D-Dimer and NLR in deceased patients were higher statistically compared with survivors (P<0.001). There was a more significant upward trend of D-Dimer and NLR during hospitalization in the deceased patients, initial D-Dimer and NLR were lower than the peak tests (MD) -25.23, 95% CI: -31.81- -18.64, P <0.001; (MD) -43.73, 95% CI:-59.28- -31.17, P <0.001. The test showed a stronger correlation between hospitalization days, PCT and peak D-Dimer than initial D-Dimer. The areas under the ROC curves of peak D-Dimer and peak NLR tests were higher than the initial tests (0.94(95%CI: 0.90-0.98) vs. 0.80 (95% CI: 0.73-0.87); 0.93 (95%CI:0.90-0.96) vs. 0.86 (95%CI:0.82-0.91). The critical value of initial D-Dimer, peak D-Dimer, initial NLR and peak NLR was 0.73 mg/L, 3.78 mg/L,7.13 and 14.31 respectively. 35 (10.03%) patients were intubated. In the intubated patients, initial and peak D-Dimer and NLR were much higher than non-intubated patients (P<0.001). The critical value of initial D-Dimer, peak D-Dimer, initial NLR and peak NLR in prognosticate of intubation was 0.73 mg/L, 12.75 mg/L,7.28 and 27.55. The multivariable Cox regression analysis showed that age (HR 1.04, 95% CI 1.00-1.07, P=0.01), the peak D-Dimer (HR 1.03, 95% CI 1.01-1.04, P<0.001) were prognostic factors for COVID-19 patients’death. Conclusions To dynamically observe the ratio of D-Dimer and NLR was more valuable during the prognosis of COVID-19. The rising trend in D-Dimer and NLR, or the test results higher than the critical values may indicate a risk of death for participants with COVID-19.

Clinical features of middle-aged patients died of 2019 Novel Coronavirus–Infected Pneumonia (preprint)

Background Since December, 2019, the emerge of a Novel Coronavirus Disease 2019 (COVID-19) have caused global concern, the majority viewpoints are that the deaths are related to advanced ages, however, the emergence of younger deaths needs immediate attention.Methods Clinical characteristics, laboratory results, chest CT scans and treatment measures were retrospectively reviewed for six deceased patients under 60 years old with confirmed COVID-19 who were admitted to Wuhan Pulmonary Hospital in Wuhan, Hubei Province, China, from 6th January to 4th March, 2020.Results The age range of the patients was 50.17 ± 3.25 years (45–55 years), none of them had underlying diseases. All of patients presented with the symptoms of fever, respiratory system and digestive system. The level of albumin and lymphocyte counts decreased early in the stages of the disease, and then gradually increased. The neutrophil to lymphocyte ratio (NLR) increased (higher than normal range) in early stage and gradually decreased when the disease progressed. All the six patients showed ground-glass opacity (GGO) and bilateral patchy shadowing in early stage under the computed tomography (CT). All the patients died of severe pneumonia and multiple organ failure.Conclusions The decreased level of serum albumin occurred in the early stages of the disease, and delays in the first admission to hospital probably aggravate the disease development. The increase of the NLR in early stage of disease may be a risk of death for COVID-19. These findings may provide useful information for optimizing supportive care for COVID-19 pneumonia.