ABSTRACT
OBJECTIVE: This research aims to develop a laboratory model that can accurately distinguish pneumonia from nonpneumonia in patients with COVID-19 and to identify potential protective factors against lung infection. METHODS: We recruited 50 patients diagnosed with COVID-19 infection with or without pneumonia. We selected candidate predictors through group comparison and punitive least absolute shrinkage and selection operator (LASSO) analysis. A stepwise logistic regression model was used to distinguish patients with and without pneumonia. Finally, we used a decision-tree method and randomly selected 50% of the patients 1000 times from the same specimen to verify the effectiveness of the model. RESULTS: We found that the percentage of eosinophils, a high-fluorescence-reticulocyte ratio, and creatinine had better discriminatory power than other factors. Age and underlying diseases were not significant for discrimination. The model correctly discriminated 77.1% of patients. In the final validation step, we observed that the model had an overall predictive rate of 81.3%. CONCLUSION: We developed a laboratory model for COVID-19 pneumonia in patients with mild to moderate symptoms. In the clinical setting, the model will be able to predict and differentiate pneumonia vs nonpneumonia before any lung computed tomography findings. In addition, the percentage of eosinophils, a high-fluorescence-reticulocyte ratio, and creatinine were considered protective factors against lung infection in patients without pneumonia.
Subject(s)
COVID-19 , Models, Statistical , Adult , Blood Cell Count , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19 Testing , Creatinine/analysis , Decision Trees , Female , Humans , Laboratories , Male , Middle Aged , Predictive Value of Tests , Reticulocytes/cytology , Tomography, X-Ray Computed , Young AdultABSTRACT
OBJECTIVES: The study aimed to assess COVID-19 impact on the morbidity and mortality of vasooclusive crisis (VOC) in sickle cell anaemia (SCA) patients. METHODS: A prospective cohort study of 100 SCA patients; 50 with COVID-19 (COVID group) and 50 without (non-COVID group). All patients signed written informed consent. RESULTS: The COVID group had a significantly higher VOC episode median per year; 3 (IQR,1-6) vs 2 (IQR,2-12) (P < 0.05). The need for hospitalisation was similar in both groups. The non-COVID group had more history of culture-proven infection (P = 0.05). The COVID-group had more osteonecrosis (P < 0.05), splenic sequestration, splenomegaly and hepatic crisis (P = 0.05, 0.006, 0.02; respectively) and significantly higher (P < 0.05) symptoms of fever, cough, fatigue, abdominal pain and anosmia. Mean haemoglobin, lymphocyte subset, platelets, and reticulocytes were reduced in both groups, while lactate dehydrogenase and ferritin levels were significantly elevated. In the COVID group, the rise in white blood cell count, reticulocyte percentage, platelets and ferritin was subdued (P < 0.05). Two patients in the COVID group and 3 in the non-COVID group died; there was no statistically significant difference in mortality. CONCLUSIONS: Although COVID-19 may have triggered the onset of VOC, it did not significantly influence VOC-related morbidity or mortality in this SCA cohort.
Subject(s)
Acute Chest Syndrome/blood , Acute Chest Syndrome/epidemiology , Anemia, Sickle Cell/blood , Anemia, Sickle Cell/epidemiology , COVID-19/blood , COVID-19/epidemiology , SARS-CoV-2 , Acute Chest Syndrome/mortality , Adult , Anemia, Sickle Cell/mortality , COVID-19/mortality , Cohort Studies , Comorbidity , Female , Ferritins/blood , Hospitalization , Humans , L-Lactate Dehydrogenase/blood , Leukocyte Count , Lymphocyte Count , Male , Platelet Count , Prospective Studies , ReticulocytesABSTRACT
Chronic inflammation is now widely recognized to play important roles in many commonly occurring diseases, including COVID-19. The resolution response to this chronic inflammation is an active process governed by specialized pro-resolving mediators (SPMs) like the lipid mediators known as lipoxins. The biosynthesis of lipoxins is catalyzed by several lipoxygenases (LOXs) from arachidonic acid. However, the molecular details of the mechanisms involved are not well known yet. In this paper, we have combined molecular dynamics (MD) simulations and quantum mechanics/molecular mechanics (QM/MM) calculations to analyze how reticulocyte 15-LOX-1 catalyzes the production of lipoxins from 5(S),15(S)-diHpETE. Our results indicate that the dehydration mechanism from 5(S),15(S)-diHpETE, via the formation of an epoxide, presents huge energy barriers even though it was one of the two a priori synthetic proposals. This result is compatible with the fact that no epoxide has been directly detected as an intermediate in the catalytic formation of lipoxins from 5(S),15(S)-diHpETE. Conversely, the oxygenation of 5(S),15(S)-diHpETE at C14 is feasible because there is an open channel connecting the protein surface with this carbon atom, and the energy barrier for oxygen addition through this channel is small. The analysis of the following steps of this mechanism, leading to the corresponding hydroperoxide at the 15-LOX-1 active site, indicates that the oxygenation mechanism will lead to the formation of lipoxinB4 after the final action of a reductase. In contrast, our calculations are in agreement with experiments that lipoxinA4 cannot derive from 5(S),15(S)-diHpETE by either of the two proposed mechanisms and that 5(S),15(S)-diHETE is not an intermediate of lipoxin biosynthesis catalyzed by 15-LOX-1.