Platelets in the perspective of COVID-19; pathophysiology of thrombocytopenia and its implication as prognostic and therapeutic opportunity

Indicators of stress hematopoiesis in the blood predict COVID-19 progression in patients over 65 years old

OBJECTIVES

Advanced age is a well-established risk factor for severe coronavirus disease 2019 (COVID-19). Exacerbated inflammation affects multiple organs, among which hematopoiesis responds by increased output of various cells. We aimed to determine the association between COVID-19 progression and large immature cell (LIC) counts, changes in erythrocyte and platelet distribution widths (RDW, PDW) with reference to patients' age.

METHODS

A total of 755 patients with complete blood cell (CBC) analysis in the first 24 h of hospitalization were enrolled. Patients were divided into two groups: under and above 65 years of age.

RESULTS

The LIC counts were different in both groups (p < 0.003). However, only the senior patients had markedly different values of RDW and PDW (p < 0.001). The receiver operating characteristic (ROC) curve analysis provided increased LIC (AUC = 0.600), RDW (AUC = 0.609), PDW (AUC = 0.556), and platelet to LIC ratio (AUC = 0.634) as significant in discriminating outcome in the older group. Importantly, these results were not repeated in the younger patients. In the elderly, the progression was predicted with LIC cut-off at ≥ 0.305 × 109/L (OR = 3.166) and RDW over 12.15% (OR = 2.081).

DISCUSSION

Aging is characterized by a decline in immunological competence with a compromised control of inflammation leading to a proinflammatory state. This background together with the actions of pathogens may lead to emergency myelopoiesis.

CONCLUSION

Our results point to the important differences between age groups regarding CBC-related parameters of stress hematopoiesis during severe infection. Higher LIC, RDW and PDW levels were reliable in the early identification of COVID-19 progression only in the elderly.

Impact of Hyponatremia on COVID-19-Related Outcomes: A Retrospective Analysis

BACKGROUND

Sodium disturbances are observed in one-third of patients with COVID-19 and result from multifaceted mechanisms. Notably, hyponatremia is associated with disease progression and mortality.

AIM

We aimed to analyze the impact of hyponatremia on COVID-19 outcomes and its correlation with clinical and laboratory parameters during the first wave.

METHODS

We evaluated the sodium levels of 558 patients with COVID-19 between 21 March 2020, and 31 July 2020, at a single center. We performed linear regression analyses to explore the correlation of sodium levels with COVID-19-related outcomes, demographic data, signs and symptoms, and laboratory parameters. Next, we conducted Pearson correlation analyses. A p-value < 0.05 was considered significant.

RESULTS

Hyponatremia was found in 35.3% of hospitalized patients with COVID-19. This was associated with the need for intensive care transfer (B = -1.210, p = 0.009) and invasive mechanical ventilation (B = -1.063, p = 0.032). Hyponatremia was frequently found in oncologic patients (p = 0.002) and solid organ transplant recipients (p < 0.001). Sodium was positively associated with diastolic blood pressure (p = 0.041) and productive cough (p = 0.022) and negatively associated with dry cough (p = 0.032), anorexia (p = 0.004), and nausea/vomiting (p = 0.007). Regarding the correlation of sodium levels with other laboratory parameters, we observed a positive correlation with hematocrit (p = 0.011), lymphocytes (p = 0.010), pCO2 (p < 0.0001), bicarbonate (p = 0.0001), and base excess (p = 0.008) and a negative correlation with the neutrophil-to-lymphocyte ratio (p = 0.009), the platelet-to-lymphocyte ratio (p = 0.033), and arterial blood glucose (p = 0.016).

CONCLUSIONS

Hyponatremia is a risk factor for adverse outcomes in COVID-19 patients. It is associated with demographic data and clinical and laboratory parameters. Therefore, hyponatremia is an important tool for risk stratification in COVID-19 patients.

Catastrophic thrombotic events with partial bilateral amputation of legs and fingers in a 12-year-old girl with COVID-19 in Brazil: case report

The first case of COVID-19 was detected in Dec 2019, in China. The disease shortly evolved into a pandemic and imposed an unparalleled health and social burden on mankind. Severe forms of COVID-19 mainly affect adults, especially the elderly and those with comorbidities. We report a severe case of COVID-19 in a previously healthy 12-year-old female who was admitted to the emergency room on May 26, 2020, with fever, abdominal pain, vomiting, and diarrhea. During the hospital stay, she tested positive for SARS-CoV-2 and developed multiple organ failure and catastrophic thrombotic events resulting in bilateral amputation of legs and fingers. She was discharged from the hospital for outpatient follow-up after 107 days. By the time this report was written, the patient was undergoing prosthesis prescription and training and regaining her independence to walk.

The Ways of the Virus: Interactions of Platelets and Red Blood Cells with SARS-CoV-2, and Their Potential Pathophysiological Significance in COVID-19

The hematological effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are important in COVID-19 pathophysiology. However, the interactions of SARS-CoV-2 with platelets and red blood cells are still poorly understood. There are conflicting data regarding the mechanisms and significance of these interactions. The aim of this review is to put together available data and discuss hypotheses, the known and suspected effects of the virus on these blood cells, their pathophysiological and diagnostic significance, and the potential role of platelets and red blood cells in the virus's transport, propagation, and clearance by the immune system. We pay particular attention to the mutual activation of platelets, the immune system, the endothelium, and blood coagulation and how this changes with the evolution of SARS-CoV-2. There is now convincing evidence that platelets, along with platelet and erythroid precursors (but not mature erythrocytes), are frequently infected by SARS-CoV-2 and functionally changed. The mechanisms of infection of these cells and their role are not yet entirely clear. Still, the changes in platelets and red blood cells in COVID-19 are significantly associated with disease severity and are likely to have prognostic and pathophysiological significance in the development of thrombotic and pulmonary complications.

Transforming growth factor beta 1 (TGF-β1) in COVID-19 patients: relation to platelets and association with the disease outcome

Transforming growth factor beta (TGF-β) is a ubiquitously distributed cytokine known to contribute to the pathogenesis of numerous pathological processes. The aim of this study was to measure serum concentrations of TGF-β1 in severely ill COVID-19 patients and to analyze its relationship with selected hematological and biochemical parameters and with the disease outcome. The study population included 53 COVID-19 patients with severe clinical expression of the disease and 15 control subjects. TGF-β1 was determined in serum samples and supernatants from PHA-stimulated whole blood cultures using ELISA assay. Biochemical and hematological parameters were analyzed using standard accepted methods. Our results showed that serum levels of TGF-β1 in COVID-19 patients and controls correlate with the platelet counts. Also, positive correlations of TGF-β1 with white blood cell and lymphocyte counts, platelet-to-lymphocyte (PLR) ratio, and fibrinogen level were shown, while negative correlations of this cytokine with platelet distribution width (PDW), D-dimer and activated partial thromboplastin time (a-PTT) values in COVID-19 patients were observed. The lower serum values of TGF-β1 were associated with the unfavorable outcome of COVID-19. In conclusion, TGF-β1 levels were strongly associated with platelet counts and unfavorable disease outcome of severely ill COVID-19 patients.

Comparison of platelet-and endothelial-associated biomarkers of disease activity in people hospitalized with Covid-19 with and without HIV co-infection

Introduction

SARS-CoV-2 elicits a hyper-inflammatory response that contributes to increased morbidity and mortality in patients with COVID-19. In the case of HIV infection, despite effective anti-retroviral therapy, people living with HIV (PLWH) experience chronic systemic immune activation, which renders them particularly vulnerable to the life-threatening pulmonary, cardiovascular and other complications of SARS-CoV-2 co-infection. The focus of the study was a comparison of the concentrations of systemic indicators o\f innate immune dysfunction in SARS-CoV-2-PCR-positive patients (n=174) admitted with COVID-19, 37 of whom were co-infected with HIV.

Methods

Participants were recruited from May 2020 to November 2021. Biomarkers included platelet-associated cytokines, chemokines, and growth factors (IL-1β, IL-6, IL-8, MIP-1α, RANTES, PDGF-BB, TGF-β1 and TNF-α) and endothelial associated markers (IL-1β, IL-1Ra, ICAM-1 and VEGF).

Results

PLWH were significantly younger (p=0.002) and more likely to be female (p=0.001); median CD4+ T-cell count was 256 (IQR 115 -388) cells/μL and the median HIV viral load (VL) was 20 (IQR 20 -12,980) copies/mL. Fractional inspired oxygen (FiO2) was high in both groups, but higher in patients without HIV infection (p=0.0165), reflecting a greater need for oxygen supplementation. With the exception of PDGF-BB, the levels of all the biomarkers of innate immune activation were increased in SARS-CoV-2/HIV-co-infected and SARS-CoV-2/HIV-uninfected sub-groups relative to those of a control group of healthy participants. The magnitudes of the increases in the levels of these biomarkers were comparable between the SARS-CoV-2 -infected sub-groups, the one exception being RANTES, which was significantly higher in the sub-group without HIV. After adjusting for age, sex, and diabetes in the multivariable model, only the association between HIV status and VEGF was statistically significant (p=0.034). VEGF was significantly higher in PLWH with a CD4+ T-cell count >200 cells/μL (p=0.040) and those with a suppressed VL (p=0.0077).

Discussion

These findings suggest that HIV co-infection is not associated with increased intensity of the systemic innate inflammatory response during SARS-CoV-2 co-infection, which may underpin the equivalent durations of hospital stay, outcome and mortality rates in the SARS-CoV-2/HIV-infected and -uninfected sub-groups investigated in the current study. The apparent association of increased levels of plasma VEGF with SARS-CoV-2/HIV co-infection does, however, merit further investigation.

Platelet role in the prediction of MIS-C severity

Introduction

Multisystem inflammatory syndrome in children (MIS-C) has been reported as one of the cytokine storm syndromes associated with COVID-19. Despite the several proposed diagnostic criteria, MIS-C remains a diagnostic and clinical challenge. Recent studies have demonstrated that platelets (PLTs) play a crucial role in COVID-19 infection and its prognosis. This study aimed to investigate the clinical importance of PLT count and PLT indices in predicting MIS-C severity in children.

Patients and methods

We conducted a retrospective single-center study at our university hospital. A total of 43 patients diagnosed with MIS-C during a 2-year period (from October 2020 to October 2022) were included in the study. MIS-C severity was evaluated according to the composite severity score.

Results

Half of the patients were treated in the pediatric intensive care unit. No single clinical sign was associated with a severe condition, except for shock (p = 0.041). All the routine biomarkers, such as complete blood count (CBC) and C-reactive protein (CRP), used for MIS-C diagnosis were significant in predicting MIS-C severity. Single PLT parameters, such as mean PLT volume, plateletcrit, or PLT distribution width, did not differ between the severity groups. However, we found that a combination of PLT count and the previously mentioned PLT indices had the potential to predict MIS-C severity.

Conclusions

Our study emphasizes the importance of PLT in MIS-C pathogenesis and severity. It revealed that together with routine biomarkers (e.g., CBC and CRP), it could highly improve the prediction of MIS-C severity.

Status of major hemostatic components in the setting of COVID-19: the effect on endothelium, platelets, coagulation factors, fibrinolytic system, and complement

The coagulation, fibrinolytic, anticoagulation, and complement systems are in delicate balance with the vessel wall endothelium ensuring appropriate hemostasis. Coagulopathy in coronavirus disease 2019 (COVID-19) is not a simple disorder of one hemostatic component but a complicated process affecting most of the hemostasis system. COVID-19 disturbs the balance between the procoagulant systems and the regulatory mechanisms. Here, we investigate the effect of COVID-19 on key hemostatic components, including platelets, endothelial cells, coagulation factors, fibrinolytic system, anticoagulant protein system, and complement system, to improve our understanding of the pathophysiological processes underlying COVID-19 coagulopathy based on evidence.

Hematological ratios in coronavirus disease 2019 patients with and without invasive mechanical ventilation

Patients with the most severe form of coronavirus disease 2019 (COVID-19) often require invasive ventilation. Determining the best moment to intubate a COVID-19 patient is complex decision and can result in important consequences for the patient. Therefore, markers that could aid in clinical decision-making such as hematological indices are highly useful. These markers are easy to calculate, do not generate extra costs for the laboratory, and are readily implemented in routine practice. Thus, this study aimed to investigate differences in the ratios calculated from the hemogram between patients with and without the need for invasive mechanical ventilation (IMV) and a control group. This was an observational retrospective analysis of 212 patients with COVID-19 that were hospitalized between April 1, 2020 and March 31, 2021 who were stratified as IMV (n = 129) or did not require invasive mechanical ventilation (NIMV) (n = 83). A control group of 198 healthy individuals was also included. From the first hemogram of each patient performed after admission, the neutrophil-to-lymphocyte ratio (NLR), the derived NLR (d-NLR), the lymphocyte-to-monocyte ratio, the platelet-to-lymphocyte ratio, the neutrophil-to-platelet ratio (NPR), and the systemic immune-inflammation index (SII) were calculated. All hematological ratios exhibited significant differences between the control group and COVID-19 patients. NLR, d-NLR, SII, and NPR were higher in the IMV group than they were in the NIMV group. The hematological indices addressed in this study demonstrated high potential for use as auxiliaries in clinical decision-making regarding the need for IMV.

Assessment of the psycho-emotional state of patients after COVID-19-associated pneumonia in relationship with laboratory indicators

The aim. To study peculiarities and association of psychological and laboratory indicators in patients with cardiovascular diseases (CVD) who underwent COVID-19 to clarify the factors affecting the possibility of developing delayed psychological and cardiovascular adverse events.

Methods. The study enrolled 350 patients with COVID-19. Group 1 consisted of 92 patients without CVD, Group 2 – of 258 patients with CVD. Indicators of laboratory and psychological parameters were assessed according to the data of psychological questionnaire using GAD-7 (General Anxiety Disorder-7), PHQ-9 (Patient Health Questionnaire-9), PSS (Perceived Stress Scale) screening scales and SF-36. Parameters of complete blood count and biochemical blood tests were measured during hospitalization and three months after discharge from the monohospital.

Results. After three months, in the general group of patients, signs of anxiety and depression were detected in more than 30 % of the examined patients, signs of stress – in 10.4 %. In the group with CVD, psycho-emotional disorders were identified in 1/4 of the patients, and severe stress – in 8 % of those included in the study. In addition, it was registered that the indicators of erythrocyte sedimentation rate, fibrinogen, high-sensitivity C-reactive protein (CRP), homocysteine and IL-6 remained at a higher level in the second group.

Correlation analysis showed that the psychological component of health is interconnected with the level of neutrophils (p = 0.044) and fibrinogen (p = 0.050); the physical component of health is correlated with the level of erythrocytes (p = 0.030), hemoglobin (p = 0.015), CRP (p = 0.002), creatine phosphokinase (p = 0.036) and glucose (p = 0.017). Regression analysis revealed that in patients with CVD three months after hospitalization, an increased glucose index contributes to deterioration, and increased hematocrit and mean hemoglobin concentration improve the quality of life of patients.

Conclusion. Laboratory markers that maintain the duration of a prolonged vascular reaction, violation of the rheological and metabolic properties of blood, determine the nature of the development of both psychological and cardiovascular complications.

Clinical Significance and Diagnostic Utility of NLR, LMR, PLR and SII in the Course of COVID-19: A Literature Review

Nowadays, society is increasingly struggling with infectious diseases that are characterized by severe course and even death. Recently, the whole world has faced the greatest epidemiological threat, which is COVID-19 caused by SARS CoV-2 virus. SARS CoV-2 infection is often accompanied by severe inflammation, which can lead to the development of different complications. Consequently, clinicians need easily interpreted and effective markers of inflammation that can predict the efficacy of the treatment and patient prognosis. Inflammation is associated with changes in many biochemical and hematological parameters, including leukocyte counts and their populations. In COVID-19, changes in leukocytes count populations such as neutrophils, lymphocytes or monocytes are observed. The numerous research confirm that indicators like neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), platelets-to-lymphocyte ratio (PLR) and systemic inflammatory index (SII) may prove effective in assessment patient prognosis and choosing optimal therapy. Therefore, in this review, we would like to summarize the latest knowledge about the diagnostic utility of systemic inflammatory ratios - NLR, LMR, PLR and SII in patients with COVID-19. We focused on the papers evaluating the diagnostic utility of inflammatory ratios using ROC curve published in the recent 3 years. Identification of biomarkers associated with inflammation would help the selection of patients with severe course of COVID-19 and high risk of death.

Development and validation of an efficient nomogram for risk assessment of norovirus infection in pediatric patients

This study aimed to establish a predictive model and nomogram based on routine laboratory blood indicators and clinical symptoms, subsequently providing a rapid risk assessment of norovirus (NoV) infection in children. This retrospective study enrolled 307 pediatric patients with symptoms of acute gastroenteritis and detected NoV using real-time quantitative polymerase chain reaction. Significant indicators selected by multivariate logistic regression, including routine blood tests and consultation symptoms, were used to develop the nomogram. We divided the sample into training and internal validation sets and performed external validation of the final model. Furthermore, we evaluated the clinical performance using the Akaike information criterion (AIC), area under the curve (AUC), calibration curve, decision curve analysis (DCA), sensitivity, specificity, concordance rate, positive predictive value, and negative predictive value. Overall, 153 cases were NoV-PCR-positive, and 154 were negative. The multivariate logistic regression included five predictors of NoV infection, including symptoms of vomiting, upper respiratory tract infection, and indicators of white blood cells, lymphocyte absolute counts, and platelet counts. The nomogram showed a significant predictive value with overall internal set diagnosis, with an AUC of 0.827 (95% confidence interval (CI): 0.785–0.868), and 0.812 (95% CI: 0.755–0.869) with 0.799 (95% CI: 0.705–0.894) in the training and internal validation sets, respectively. Nevertheless, the AUC in the external validation set was higher (0.915; 95% CI: 0.862–0.968). This nomogram is a useful tool for risk assessment for NoV infection. Moreover, the evaluated indicators are accessible, substantially reducing the time for laboratory testing.

The importance of using routine laboratory tests in the diagnosis and prognosis of patients with coronavirus disease 2019: Shedding light on clinical laboratory data in COVID-19

BACKGROUND

Novel coronavirus (COVID-19) pandemic has become a global concern and requires early detection, isolation, and treatment. Our purpose is to find some beneficial information by analyzing the COVID-19 laboratory data to provide guidance for clinical practice.

MATERIAL AND METHODS

In this study, 174 patients with confirmed COVID-19 infection were admitted. We evaluated the hematological and biochemical parameters in these patients and in 80 healthy individuals.

RESULTS

We found that there was significant difference between WBC, LYM, RBC, HB, and HCT parameters of patients and healthy counterparts (p < .001), though there was no remarkable change between NEU, MONO, PLT, and other characteristics of RBC values of patients and the control group (p ≥ .09). Among the evaluated biochemical parameters, the values of CK-MB and LDH in the patient group were significantly different from the control group (p < .01), while other biochemical indicators were in the normal range.

CONCLUSION

Several hematological and biochemistry parameters, in particular WBC, LYM, RBC, HB, HCT, CK-MB, and LDH, could be beneficial supplementary approach for COVID-19 infection evaluation to confirm risk stratification and effective management.

Characterization of blood biomarkers in prospective follow-up of patients with cardiovascular pathology in combination with type 2 diabetes mellitus after COVID-19 associated pneumonia

The study of the characteristics and dynamics of laboratory biomarkers in patients with cardiovascular diseases (CVD) with type 2 diabetes mellitus who underwent COVID-19-associated pneumonia is of great clinical importance for preventing the risk of adverse events. IN the study we used data from 65 patients in the present work. Patients were divided into 2 groups: group 1 included patients with CVD: arterial hypertension (AH) in combination with coronary artery disease (CAD) without DM2 (n=45), group 2 included patients with CVD and DM2 (n=20). Patients were examined at baseline in the infectious disease hospital and 3 months after discharge. During laboratory examination of blood biosamples we evaluated parameters of general blood test; biochemical and immunologicai parameters; elastic properties of the vascular wall. The analyzed leukocyte parameters and their index coefficients - increase in NLR ratio (neutrophils/lymphocytes) and decrease in LYM/CRP ratio (lymphocytes/CRP) were more significantly changed in DM2 group. Patients in both groups had a significant excess of baseline max CRP concentrations with decrease in parameters after 3 months, but with persistent excess values in group 2. Three months after discharge patients with DM2 had levels of hs-CRP, IL-1β and TNFa and NT-proBNP, that exceeded both the reference values and those in group 1, which reflected the presence of more pronounced vascular inflammatory potential for possible adverse events in this group of patients in post-COVID period. The method of multiple regression showed that DM2 is an independent risk factor for increased stiffness of the vascular wall. Thus, dynamic control of laboratory parameters has prognostic value in assessing the nature of the course of COVID-19 associated pneumonia in patients with CVD and DM2 developing an algorithm for personalized monitoring of patients in the post-COVID period with the aim of timely prevention of unwanted vascular complications.

Relative Hypercoagulopathy of the SARS-CoV-2 Beta and Delta Variants when Compared to the Less Severe Omicron Variants Is Related to TEG Parameters, the Extent of Fibrin Amyloid Microclots, and the Severity of Clinical Illness

Earlier variants of SARS-CoV-2 have been associated with plasma hypercoagulability (as judged by thromboelastography) and an extensive formation of fibrin amyloid microclots, which are considered to contribute to the pathology of the coronavirus 2019 disease (COVID-19). The newer Omicron variants appear to be far more transmissible, but less virulent, even when taking immunity acquired from previous infections or vaccination into account. We here show that while the clotting parameters associated with Omicron variants are significantly raised over those of healthy, matched controls, they are only raised to levels significantly lower than those seen with more severe variants such as beta and delta. We also observed that individuals infected with omicron variants manifested less extensive microclot formation in platelet-poor plasma compared with those harboring the more virulent variants. The measurement of clotting effects between the different variants acts as a kind of "internal control" that demonstrates the relationship between the extent of coagulopathies and the virulence of the variant of interest. This adds to the evidence that microclots may play an important role in reflecting the severity of symptoms observed in COVID-19.

Risk Factors Associated with Mortality in COVID-19 Hospitalized Patients: Data from the Middle East

This study aimed to assess the risk factors for COVID-19 mortality among hospitalized patients in Jordan. All COVID-19 patients admitted to a tertiary hospital in Jordan from September 20, 2020, to August 8, 2021, were included in this study. Demographics, clinical characteristics, comorbidities, and laboratory results were extracted from the patients' electronic records. Multivariable logistic and machine learning (ML) methods were used to study variable importance. Out of 1,613 COVID-19 patients, 1,004 (62.2%) were discharged from the hospital (survived), while 609 (37.8%) died. Patients who were of elderly age (>65 years) (OR, 2.01; 95% CI, 1.28-3.16), current smokers (OR, 1.61; 95%CI, 1.17-2.23), and had severe or critical illness at admission ((OR, 1.56; 95%CI, 1.05-2.32) (OR, 2.94; 95%CI, 2.02-4.27); respectively), were at higher risk of mortality. Comorbidities including chronic kidney disease (OR, 2.90; 95% CI, 1.90-4.43), deep venous thrombosis (OR, 2.62; 95% CI, 1.08-6.35), malignancy (OR, 2.22; 95% CI, 1.46-3.38), diabetes (OR, 1.31; 95% CI, 1.04-1.65), and heart failure (OR, 1.51; 95% CI, 1.02-2.23) were significantly associated with increased risk of mortality. Laboratory abnormalities associated with mortality included hypernatremia (OR, 11.37; 95% CI, 4.33-29.81), elevated aspartate aminotransferase (OR, 1.81; 95% CI, 1.42-2.31), hypoalbuminemia (OR, 1.75; 95% CI, 1.37-2.25), and low platelets level (OR, 1.43; 95% CI, 1.05-1.95). Several demographic, clinical, and laboratory risk factors for COVID-19 mortality were identified. This study is the first to examine the risk factors associated with mortality using ML methods in the Middle East. This will contribute to a better understanding of the impact of the disease and improve the outcome of the pandemic worldwide.

Platelet Count in Patients with SARS-CoV-2 Infection: A Prognostic Factor in COVID-19

COVID-19 patients may manifest thrombocytopenia and some of these patients succumb to infection due to coagulopathy. The aim of our study was to examine platelet count values in patients infected with SARS-CoV-2, comparing them to a control group consisting of non-COVID-19 patients. Moreover, we evaluated the correlation between the platelet value and the respiratory alteration parameters and the outcome (hospitalization and mortality) in COVID-19 patients. The mean platelet values (×109/L) differed between patients with positive or negative SARS-CoV-2 swabs (242.1 ± 92.1 in SARS-CoV-2 negative vs. 215.2 ± 82.8 in COVID-19 patients, p < 0.001). In COVID-19 patients, the platelet count correlated with the A-aO2 gradient (p = 0.001, rho = −0.149), with its increase over the expected (p = 0.013; rho = −0.115), with the PaO2 values (p = 0.036; rho = 0.093), with the PCO2 values (p = 0.003; rho = 0.134) and with the pH values (p = 0.016; rho = −0.108). In COVID-19 negative patients, the platelet values correlated only with the A-aO2 gradient: (p = 0.028; rho = −0.101). Patients discharged from emergency department had a mean platelet value of 234.3 ± 68.7, those hospitalized in ordinary wards had a mean value of 204.3 ± 82.5 and in patients admitted to sub-intensive/intensive care, the mean value was 201.7 ± 75.1. In COVID-19 patients, the survivors had an average platelet value at entry to the emergency department of 220.1 ± 81.4, while that of those who died was 206.4 ± 87.7. Our data confirm that SARS-CoV-2 infection may induce thrombocytopenia, and that the reduction in platelet counts could be correlated with the main blood gas parameters and with clinical outcome; as a consequence, platelet count could be an important prognostic factor to evaluate and stratify COVID-19 patients.

Baseline Thrombocytopenia and Disease Severity Among COVID-19 Patients, Tibebe Ghion Specialized Hospital COVID-19 Treatment Center, Northwest Ethiopia

Background

Thrombocytopenia and platelet indices in COVID-19 patients were important for prompt treatment and management of the disease. Therefore, the main objective of this study was to assess the prevalence of thrombocytopenia, platelet indices, and its association with disease severity among COVID-19 patients at the Tibebe Ghion Specialized Hospital, COVID-19 treatment center, Northwest Ethiopia.

Methods

A cross-sectional study was conducted among 117 conveniently recruited COVID-19 patients from March to June 2021. Socio-demographic and clinical data were collected using a structured questionnaire and checklist, respectively. The platelet parameters were analyzed by the Mindray-BC 5800 automated hematological analyzer. ANOVA and Kruskal-Wallis tests were used to compare the difference between parametric and non-parametric continuous variables, respectively. Binary logistic regression was used to identify the factors associated with thrombocytopenia. A P-value < 0.05 was defined as statistically significant for all statistical tests.

Results

Among COVID-19 patients, 45, 43 and 29 were mild, moderate and severe, respectively. 65.8% of the patients were males and 34.2% were alcohol drinkers with a mean age of 50.6 ± 15.4. Moreover, 44.4% of the patients had co-morbidity. Thrombocytopenia was presented in 23.9% of the patients. It was 4.57 (95% CI: 1.30-16.07) and 6.10 (95% CI: 1.54-24.08) times more likely in the moderate and severe cases compared to mild cases, respectively. Disease severity was also associated with PDW (P-value = 0.001).

Conclusion

Even though thrombocytopenia was not presented in most moderate and severe COVID-19 patients, thrombocytopenia and PDW were associated with disease severity.

A composite ranking of risk factors for COVID-19 time-to-event data from a Turkish cohort

Having a complete and reliable list of risk factors from routine laboratory blood test for COVID-19 disease severity and mortality is important for patient care and hospital management. It is common to use meta-analysis to combine analysis results from different studies to make it more reproducible. In this paper, we propose to run multiple analyses on the same set of data to produce a more robust list of risk factors. With our time-to-event survival data, the standard survival analysis were extended in three directions. The first is to extend from tests and corresponding p-values to machine learning and their prediction performance. The second is to extend from single-variable to multiple-variable analysis. The third is to expand from analyzing time-to-decease data with death as the event of interest to analyzing time-to-hospital-release data to treat early recovery as a meaningful event as well. Our extension of the type of analyses leads to ten ranking lists. We conclude that 20 out of 30 factors are deemed to be reliably associated to faster-death or faster-recovery. Considering correlation among factors and evidenced by stepwise variable selection in random survival forest, 10 ~ 15 factors seem to be able to achieve the optimal prognosis performance. Our final list of risk factors contain calcium, white blood cell and neutrophils count, urea and creatine, d-dimer, red cell distribution widths, age, ferritin, glucose, lactate dehydrogenase, lymphocyte, basophils, anemia related factors (hemoglobin, hematocrit, mean corpuscular hemoglobin concentration), sodium, potassium, eosinophils, and aspartate aminotransferase.

Intensive-Dose Tinzaparin in Hospitalized COVID-19 Patients: The INTERACT Study

(1) Background: It is well-established that coronavirus disease-2019 (COVID-19) is highly pro-inflammatory, leading to activation of the coagulation cascade. COVID-19-induced hypercoagulability is associated with adverse outcomes and mortality. Current guidelines recommend that hospitalized COVID-19 patients should receive pharmacological prophylaxis against venous thromboembolism (VTE). (2) INTERACT is a retrospective, phase IV, observational cohort study aiming to evaluate the overall clinical effectiveness and safety of a higher than conventionally used prophylactic dose of anticoagulation with tinzaparin administered for VTE prevention in non-critically ill COVID-19 patients with moderate disease severity. (3) Results: A total of 705 patients from 13 hospitals in Greece participated in the study (55% men, median age 62 years). Anticoagulation with tinzaparin was initiated immediately after admission. A full therapeutic dose was received by 36.3% of the participants (mean ± SD 166 ± 33 IU/Kgr/day) and the remaining patients (63.9%) received an intermediate dose (mean ± SD 114 ± 22 IU/Kgr/day). The median treatment duration was 13 days (Q1−Q3: 8−20 days). During the study (April 2020 to November 2021), 14 thrombotic events (2.0%) were diagnosed (i.e., three cases of pulmonary embolism (PE) and 11 cases of deep venous thrombosis, DVT). Four bleeding events were recorded (0.6%). In-hospital death occurred in 12 patients (1.7%). Thrombosis was associated with increasing age (median: 74.5 years, Q1−Q3: 62−79, for patients with thrombosis vs. 61.9 years, Q1−Q3: 49−72, p = 0.0149), increased D-dimer levels for all three evaluation time points (at admission: 2490, Q1−Q3: 1580−6480 vs. 700, Q1−Q3: 400−1475, p < 0.0001), one week ± two days after admission (3510, Q1−Q3: 1458−9500 vs. 619, Q1−Q3: 352−1054.5, p < 0.0001), as well as upon discharge (1618.5, Q1−Q3: 1010−2255 vs. 500, Q1−Q3: 294−918, p < 0.0001). Clinical and laboratory improvement was affirmed by decreasing D-dimer and CRP levels, increasing platelet numbers and oxygen saturation measurements, and a drop in the World Health Organization (WHO) progression scale. (4) Conclusions: The findings of our study are in favor of prophylactic anticoagulation with an intermediate to full therapeutic dose of tinzaparin among non-critically ill patients hospitalized with COVID-19.

Prospective analysis of laboratory blood parameters in patients with cardiovascular diseases who underwent COVID-19-associated pneumonia

The study of the characteristics and dynamics of laboratory biomarkers in patients with cardiovascular diseases (CVD) undergoing COVID-19-associated pneumonia may be of great clinical importance. The study included 116 patients who underwent COVID-19-associated pneumonia. The patients were divided into 2 groups. The first group included 49 patients without CVD, the second group - 67 patients with CVD. A blood sample was performed in all patients at the time of hospitalization and 3 months after discharge from the hospital. The parameters of general blood count, biochemistry, hemostasis, and biomarkers of inflammation were assessed - concentration of C-reactive protein (CRP), highly sensitive CRP (hs-CRP), homocysteine and IL-6. All patients initially underwent computed tomography of the chest organs. We found that ESR, WBC (leukocytes), NLR (neutrophils/lymphocytes ratio), fibrinogen, LDH (lactate dehydrogenase), LYM/CRP ratio (lymphocytes/CRP) were parameters that significantly distinguished patients in the 1st and 2nd groups. Three months after discharge from the hospital in patients of both groups the increased indicators approached the reference values, however, some parameters such as CRP, ESR, WBC, fibrinogen remained at a higher level in group 2 compared to group 1. Correlation analysis revealed the relationship between parameters of inflammation and hemostasis in the 2nd group of patients, which confirms the presence of latent vascular inflammatory potential in this group. It was revealed that such indicators as lymphocytes, neutrophils, APTT and LDH were associated with the initial volume of lung lesion more than 50%. Increase of these parameters by 1 unit contributes to increase in the volume of lung tissue damage by 6.5%, 6.4%, 11%, and 0.6%, respectively. Thus, dynamic control of laboratory parameters has prognostic value in assessing the nature of the course of COVID-19 associated pneumonia in patients with CVD and developing an algorithm for personalized monitoring of patients in the post-COVID period with the aim of timely correction of therapy to prevent unwanted vascular complications.