Could platelet mass index (PMI) be a new prognostic biomarker for COVID-19?

Aim: Although most patients with COVID-19 experience respiratory tract infections, severe reactions to the virus may cause coagulation abnormalities that mimic other systemic coagulopathies associated with severe infections, such as disseminated intravascular coagulation and thrombotic microangiopathy. Fluctuations in platelet markers, which are an indicator of the acute phase response for COVID-19, are of clinical importance. The aim of this study is to evaluate the relationship between disease severity and Platelet Mass Index (MPI) parameters in COVID-19 patients. Material(s) and Method(s): This retrospective observational study was conducted with patients who were diagnosed with COVID-19 in a tertiary hospital. The study was continued with the remaining 280 patients. All laboratory data were scanned retrospectively from patient files and hospital information system. Result(s): A very high positive correlation was found between PMI and PLT. The PMI value in women was significantly higher than in men. It was observed that PMI did not differ significantly in terms of mortality, intubation, CPAP and comorbidity. PMI vs. Pneumonia Ct Severity Score, biochemistry parameters (AST, CRP), hemogram parameters (WBC, HGB, HCT, MCV, LYM, MPV EO) and coagulation factors (aPTT and FIB) at various levels of positive/negative, weak and strong, and significant relationship was found. There was no significant relationship between hormone and D-dimer when compared with PMI. Discussion(s): Although platelet count alone does not provide information about the prognosis of the disease, PMI may guide the clinician as an indicator of lung damage in seriously ill patients.Copyright © 2022, Derman Medical Publishing. All rights reserved.

Particularities of hemostasis changes in COVID-19 patients.

COVID-19 infection is characterized by different clinical presentations. The thrombotic complications play the leading role in COVID-19 infection. SARS-CoV-2 virus can activate hemostasis at different levels: pulmonary tissue damage with subsequent plasma coagulation activation;local endothelial dysfunction and platelet activation during the course of the disease. Routine use of the anticoagulation treatment seems reasonable in hospitalized patients with COVID-19.Copyright © Creative Cardiology 2021.

Changes in Kawasaki disease incidence and phenotype during the COVID-19 pandemic

INTRODUCTION. The aetiology of Kawasaki disease (KD) remains unknown. Changes in infectious exposure during the COVID-19 pandemic owing to infection prevention measures may have affected the incidence of KD, supporting the pathogenic role of an infectious trigger. The purpose of this study was to evaluate the incidence, phenotype and outcome of KD before and during the COVID-19 pandemic in Denmark. METHODS. This was a retrospective cohort study based on patients diagnosed with KD at a Danish paediatric tertiary referral centre from 1 January 2008 to 1 September 2021. RESULTS. A total of 74 patients met the KD criteria of whom ten were observed during the COVID-19 pandemic in Denmark. Alof these patients were negative for SARS-CoV-2 DNA and antibodies. A high KD incidence was observed during the first six months of the pandemic, but no patients were diagnosed during the following 12 months. Clinical KD criteria were equally met in both groups. The fraction of intravenous immunoglobulin (IVIG) non-responders was higher in the pandemic group (60%) than in the in the pre-pandemic group (28.3%), although the rate of timely administered IVIG treatment was the same in both groups (>= 80%). Coronary artery dilation was observed in 21.9% in the pre-pandemic group compared with 0% in KD patients diagnosed during the pandemic. CONCLUSION. Changes in KD incidence and phenotype were seen during the COVID-19 pandemic. Patients diagnosed with KD during the pandemic had complete KD, higher liver transaminases and significant IVIG resistance but no coronary artery involvement.Copyright © 2023, Almindelige Danske Laegeforening. All rights reserved.

The Effect of CRP/Albumin, Platelet/Lymphocyte, SOFA, and APACHE II in Predicting Mortality in Covid-19 Patients in Intensive Care Unit

Objectives: It is important to predict the prognosis during hospital admission of Covid-19 patients. The purpose of this study was to see how CRP/ Albumin (CAR) and Platelet/Lymphocyte (PLR) ratios, obtained from patients in the intensive care unit (ICU) within the first 24 hours of their hospitalization with a Covid-19 diagnosis, predictmortality and how they correlated with acute physiology and chronic health evaluation (APACHE II) and sequential organ failure assessment (SOFA). Method(s): Using hospital records, records of 83 patients hospitalized in the ICU with a diagnosis of Covid-19 between 11.03.2020 and 01.01.2021 were retrospectively analyzed . Patients were divided into two groups discharged (Group I) and exits (ex) group (Group II). CAR and PLR were recorded during the first 24 hours of ICU admission, and APACHE II and SOFA scores were computed. The calculated CAR and PLR were correlated with APACHE II and SOFA scores and their association with mortality was investigated. Result(s): SOFA, APACHE II, PLO, and age were higher, and albumin was lower in patients in the mortal course (p<0.05). ROC analysis revealed that APACHE II and SOFA scores could be employed to estimate mortality. Conclusion(s): We believe that APACHE II and SOFA scores can be used to predict mortality in patients admitted to the ICU due to Covid-19, whereas CRP/Albumin and Platelet/Lymphocyte ratios cannot. Copyright © 2023 by The Cardiovascular Thoracic Anaesthesia and Intensive Care.

A rare combination of immune thrombocytopenia and disaggregation thrombocytopathy: course and termination of pregnancy complicated by COVID-19 (Clinical case)

Immune thrombocytopenia (ITP) is an autoimmune disease which is characterized by antibody-mediated destruction of platelets by the reticuloendothelial system. The rate of ITP is 3.3 per 100,000 adults per year with a prevalence of 9.5 per 100,000 adults. Pregnancy does not increase the frequency or severity of ITP, but ITP can significantly affect pregnancy and cause bleeding in women. Pregnancy requires regular control of the number of platelets: monthly in the I and II trimesters, every 2 weeks – in the III trimester, and weekly control near the delivery date. Indications for treatment are determined by the pregnant woman condition, not the fetus, since it has not been proven that the treatment reduces the risks of thrombocytopenia in newborns with the development of cerebral hemorrhage. The drug of the first line of treatment of such pathology is prednisolone at a dose of 1 mg/kg orally once a day. An increase in the number of platelets is usually observed within 3-7 days, the maximum response is determined after 2-3 weeks. If necessary, the dose can be increased. When the required level of platelets is reached, the dose can be gradually reduced by 10-20 % to the minimum dose necessary to maintain the number of platelets at an acceptable level. Thrombocytopathy can be the cause of primary hemostasis disorders, even if the number of platelets in the blood is normal. For diagnosis, tests are carried out to detect the aggregation ability of platelets. In addition, flow cytometry can be used, which makes it possible to detect the defects of surface membrane receptors, as well as defects of the end point of secretion. ITP is a common cause of thrombocytopenia after viral infections. The onset of this pathology is more often detected in the second and third weeks after the onset of COVID-19. The treatment aim is to prevent the significant bleeding in patients with COVID-19. The article presents a clinical case of a pregnant woman with ITP and thrombocytopathy, whose pregnancy was complicated by COVID-19. The patient complained on bleeding gums, the appearance of hematomas on the skin. Medical treatment of the main disease included prednisolone, eltrombopag, intravenous human immunoglobulin, transfusion of platelet concentrate. At 34–35 weeks of pregnancy alive boy was born with a body weight of 2800 g, length of 49 cm, 7–8 points on the Apgar scale. © The Author(s) 2023.

The Association of COVID-19 Severity with Laboratory Parameters, Radiologic Findings, Maternal and Neonatal Outcomes in Pregnant Women: A Multicenter Study in Indonesia

Objectives: Severe acute respiratory syndrome-coronavirus 2/COVID-19 infection is still a global concern, with pregnant women are considered as vulnerable population. Until now, the characteristics of pregnant women in Indonesia who are infected with COVID-19, as well as pregnancy and neonatal outcomes, are still unknown. This study aims to obtain national data, which are expected to be useful for the prevention and management of COVID-19 in pregnant women in Indonesia. Method(s): There were 1,427 patients recruited in this retrospective multicenter study. This study involved 11 hospitals in 10 provinces in Indonesia and was carried out using secondary patient data from April 2020 to July 2021. COVID-19 severity was differentiated into asymptomatic-to-mild symptoms and moderate-to-severe symptoms. The collected data include maternal characteristics, laboratory examinations, imaging, pregnancy outcomes, and neonatal outcomes. Result(s): Leukocyte, platelets, basophil, neutrophils segment, lymphocytes, monocytes, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, alanine aminotransferase (ALT), aspartate aminotransferase (AST), C-reactive protein (CRP), urea, and creatinine were found to be significantly associated with severity differences (p < 0.05). Moderate-severe symptoms of COVID-19 also shown to have suggestive pneumonia findings on chest X-ray findings. Patients with asymptomatic-to-mild symptoms had significantly (p < 0.001) higher recovery rate, shorter hospital stay, less intensive care unit (ICU) admission, and had more vaginal delivery. Neonates from mother with mild symptoms also had significantly (p < 0.001) higher survival rate, higher birth weight, and higher APGAR score. Conclusion(s): Several laboratory and radiology components, as well as maternal and neonatal outcomes are related to the severity of COVID-19 in pregnant women in Indonesia.Copyright © The Author(s). 2023.

Predictors of poor outcomes in patients with pandemic viral infections (influenza AH1N1pdm09, COVID-19) on a ventilator.

Considering the commonality of the pathogenetic links of the critical forms of COVID-19 and influenza AH1N1pdm09 (cytokine over-release syndrome), the question arises: will the predictors of an unfavorable outcome in patients on mechanical ventilation and, accordingly, the universal tactics of respiratory support in these diseases be identical? Objective. In a comparative aspect, to characterize patients with influenza AH1N1pdm09 and COVID-19 who were on mechanical ventilation, to identify additional clinical and laboratory risk factors for death, to determine the degree of influence of respiratory support (RP) tactics on an unfavorable outcome in the studied category of patients. Patients and methods. Patients treated on the basis of resuscitation and intensive care departments of the State Budgetary Healthcare Institution "SKIB" in Krasnodar and the State Budgetary Healthcare Institution "IB No 2" in Sochi were studied: group 1 - 31 people with influenza AH1N1pdm09 (21 people died - subgroup 1A;10 people survived - subgroup 1B) and group 2 - 50 people with COVID-19 (29 patients died - subgroup 2A;21 people survived - subgroup 2B). All patients developed hypoxemic ARF. All patients received step-by-step tactics of respiratory support, starting with oxygen therapy and ending with the use of "traditional" mechanical ventilation. Continuous variables were compared in subgroups of deceased and surviving patients for both nosologies at the stages: hospital admission;registration of hypoxemia and the use of various methods of respiratory therapy;development of multiple organ dysfunctions. With regard to the criteria for which a statistically significant difference was found (p < 0.05), we calculated a simple correlation, the relative risk of an event (RR [CI 25-75%]), the cut-off point, which corresponded to the best combination of sensitivity and specificity. Results. Risk factors for death of patients with influenza AH1N1pdm09 on mechanical ventilation: admission to the hospital later than the 8th day of illness;the fact of transfer from another hospital;leukocytosis >=10.0 x 109/l, granulocytosis >=5.5 x 109/l and LDH level >=700.0 U/l at admission;transfer of patients to mechanical ventilation on the 9th day of illness and later;SOFA score >=8;the need for pressor amines and replacement of kidney function. Predictors of poor outcome in ventilated COVID-19 patients: platelet count <=210 x 109/L on admission;the duration of oxygen therapy for more than 4.5 days;the use of HPNO and NIV as the 2nd step of RP for more than 2 days;transfer of patients to mechanical ventilation on the 14th day of illness and later;oxygenation index <=80;the need for pressors;SOFA score >=8. Conclusion. When comparing the identified predictors of death for patients with influenza and COVID-19 who needed mechanical ventilation, there are both some commonality and differences due to the peculiarities of the course of the disease. A step-by-step approach to the application of respiratory support methods is effective both in the case of patients with influenza AH1N1pdm09 and patients with COVID-19, provided that the respiratory support method used is consistent with the current state of the patient and his respiratory system, timely identification of markers of ineffectiveness of the respiratory support stage being carried out and determining the optimal moment escalation of respiratory therapy.Copyright © 2022, Dynasty Publishing House. All rights reserved.

Membrane dysfunction in patients with severe COVID-19 treated with venovenous extracorporeal membrane oxygenation - analysis from a pooled data from a single centre

Objectives: It is well known that severe COVID-19 is associated with complex immunological and inflammatory dysregulation. Both these physiopathological events translate to a high risk of major thrombotic or hemorrhagic events. In patients treated with venovenous extracorporeal membrane oxygenation (VVECMO), membrane dysfunction might affect systemic oxygenation and limit its duration-expectancy. This study aimed to assess the possible causes of extracorporeal membrane failure in COVID-19 patients and its impact on outcome. Method(s): Retrospective, single-center, observational case-control study involving adult COVID-19 patients admitted to an ECMO referral centre in a tertiary university hospital. All patients required VVECMO for acute respiratory failure, including 48 cases who needed one or more extracorporeal membrane exchanges and 45 controls (no membrane exchange). These two groups were compared for demographic characteristics, severity of the disease using validated scores (SAPS II and SOFA), duration of ECMO run, coagulation assessment, cumulative anticoagulation dose, associated complications, and outcomes (ICU and hospital mortality). Result(s): Most patients were males (71.0%) and younger than 50 years (79.5%). Median ECMO run duration was significantly longer in the case group (35.0 vs 14.0 days, p <0.001), as well as ICU length-of-stay (45.5 vs 28 days, p <0.001). Membrane exchange tended to be associated with sepsis (56% vs 33%, p=0.037), major hemorrhage (58% vs 43%, p=0.022), heparin-induced thrombocytopenia (25% vs 9%, p=0.054), higher D-dimer title (17.36 ng/dL vs 7.5 ng/dL, p=0.07) and lower platelet counts (133.000/muL vs 154.000/muL). Median SAPS II (32.0 vs 33.0, p=0.20) and the mortality (27% vs 24%, p >0.99) were similar between these groups. Conclusion(s): In patients with SARS-CoV-2 pneumonia and severe hypoxemia treated with VVECMO support the emergence of infection, coagulopathy and inflammation were associated with high risk of membrane dysfunction. No impact on mortality could be confirmed from these data. Anticoagulation monitoring and dosing strategies should be reinforced to promote membrane protection.

Diagnostic Role of Platelet to Lymphocyte Ratio and Platelet Parameters in COVID-19 Disease

Backgrounds: This study aimed to analyze the applicability of platelet parameters in assessing the severity of COVID-19 disease. Material(s) and Method(s): Patients with RT-PCR confirmed COVID-19 in the Pathology department of a tertiary care hospital in south India from June to December 2020 were included in this study. Clinical details and laboratory parameters of these patients were obtained. The difference between the studied variables in two groups was assessed using independent t-test. The optimum cut-off value of platelet to lymphocyte ratio (PLR) to differentiate between the tested groups was estimated using ROC (receiver operator curve) analysis. Finding(s): This study was conducted on 218 COVID-19 patients, of whom 17.9% showed thrombocytopenia at the time of admission. Among the hematological parameters, PLR, absolute lymphocyte count (ALC), platelet distribution width (PDW), D-dimer, and erythrocyte sedimentation rate (ESR) were significantly different between the ICU (intensive care unit) and non-ICU groups. Increased PLR values were associated with the disease severity. Conclusion(s): PLR could be used as an additional biomarker in assessing the severity of COVID-19 disease, and a cut-off value of 210.27 is optimal to differentiate severe COVID-19 disease from its mild and moderate forms with 79% specificity.Copyright © 2023, TMU Press.

Comparison of PCR-negative patients with CT findings and PCR-positive COVID-19 patients

Aim: The gold standard diagnostic method for the diagnosis of COVID-19 is based on the demonstration of viral RNA in samples taken from the upper respiratory tract in reverse transcriptase-polymerase chain reaction (RT-PCR). However, in emergencies, the World Health Organization (WHO) also recommends to use computed tomography (CT) in order to reduce the loss of time and to provide rapid diagnosis, treatment and isolation of suspicious cases. In our study, we aimed to compare the laboratory values of patients with PCR negative CT findings and PCR positive patients. Material(s) and Method(s): The medical records of 1280 COVID-19 patients registered at our Family Medicine Center were reviewed retrospectively. Result(s): In our study, it was found that 66,70 % of PCR-negative patients with CT findings were aged 60 years and older, and 50.70% of PCR-positive COVID-19 patients were between the ages of 40-59 years;61.30% of the patients with CT findings and 48% of the PCR-positive patients were male;73% of PCR-positive patients had lung involvement. When CRP, fibrinogen and D-dimer values were examined, it was found that in PCR-negative COVID-19 patients with CT findings these values were statistically significantly higher. Discussion(s): Although the definitive diagnosis of the disease is made using a PCR test, it should not be overlooked that the patients may remain PCR negative, and it should not be forgotten that thoracic tomography findings are a good diagnostic method for this group.Copyright © 2022, Derman Medical Publishing. All rights reserved.

The role of mast cells and their proteases in lung damage associated with COVID-19.

The new coronavirus infection COVID-19 (Coronavirus Disease 2019) caused by SARS-CoV-2, has posed scientific and public health challenges. The problem of treating COVID-19 still remains, and the pathogenesis of COVID-19 needs to be studied in detail, including the involvement of mast cells (MCs) and their specific proteases. The aim of this study was to characterize the role of mast cell proteases chymase, tryptase, and carboxypeptidase A3 (CPA3) in the lung damage associated with COVID-19. Methods. The study included postmortem lung biopsies from 30 patients who died of severe COVID-19, and biopsies from 9 control group patients. Histological preparations were made and protease profile and degranulation activity of MCs were analyzed. In addition, some demographic, clinical, and laboratory parameters were analyzed. Results. The average number of tryptase-positive MCs without evidence of degranulation and the total number of CPA3-positive MCs were statistically significantly higher in patients with COVID-19, and the number of tryptase-positive and CPA3-positive MCs fragments was lower compared with controls. Negative correlations were established between the numbers of tryptase-positive MCs and red blood cell count. Negative correlations were found between non-granulating tryptase-positive MCs and hemoglobin levels. Positive correlations were noted between tryptase-positive MCs and the leukocytes and eosinophils counts, and negative correlations were noted between the number of CPA3-positive cells and the platelet count. A positive correlation was found between the number of adjoining MCs, as well as fragments of tryptase-positive MCs, and the erythrocyte sedimentation rate (ESR). A negative correlation was also observed between the number of non-degranulated CPA3-positive MCs and the blood level of C-reactive protein. In patients with COVID-19, reduced degranulation activity of tryptase-positive MCs was found along with increased representation of CPA3-positive MCs. Several trends and associations with laboratory test results were noted. The potential involvement of MCs in the development of anemia and thrombocytopenia is considered. Associations were established between tryptase-positive MCs and the peripheral blood counts of leukocytes and eosinophils, as well as ESR. Conclusion. The results obtained are highly contradictory. Since many aspects of the involvement of MCs and their proteases in COVID-19 pathogenesis are still unknown, studies with larger cohorts of patients are needed.Copyright © Budnevsky A.V. et al., 2023.

Sars cov-2 infection in a neonate in ghana: A case report

Backgrounds: The clinical and socioeconomic effects of COVID-19 are still being felt through-out the world. The disease affects people of all age groups, but it is known to have a milder clinical course in children including neonates. There is paucity of data from Sub-Saharan Africa on neonatal COVID-19 infection, and no such case has been reported in the literature in Ghana. Case presentation: This study presented a case report of a neonate who was found to be positive for COVID-19 infection after presenting symptoms such as respiratory distress, rhinorrhoea, and cough. This neonate was managed with in-hospital standard protocol for sepsis with a focus on pneumonia. Conclusion(s): The national guidelines on COVID-19 management were used for the neonate who was recovered and discharged.Copyright © 2021, TMU Press.

Clinical profile and outcomes of COVID-19 infection during the first wave in children with hematological illnesses and cancer: An observational study from a tertiary care center in North India

Background: Patients with cancer are at a higher risk of getting infected with the severe acute respiratory syndrome coronavirus 2 owing to their immunocompromised state. Providing care to these patients amidst the first wave of the coronavirus disease-2019 (COVID-19) pandemic was extremely challenging. Objective(s): This study was aimed at evaluating the clinical profile and disease-related outcomes of pediatric patients with hematological illnesses and cancer. Material(s) and Method(s): This retrospective study was conducted at a tertiary care center in North India during the first wave of the pandemic from March 2020 to December 2020. Children aged up to 18 years, who were treated for a hematological illness or malignancy or underwent hematopoietic stem cell transplantation (HSCT) and tested positive for COVID-19 regardless of symptoms were included in the study. Baseline demographic data related to the age, diagnosis, treatment status, and chemotherapy protocol used were collected. Outcomes including the cure rates, comorbidities, and sequelae were recorded. Result(s): A total of 650 tests for COVID-19 were performed for 181 children;22 patients were found to be COVID-19 positive. The most common diagnosis was acute leukemia (63.6%). None of the patients developed COVID-19 pneumonia. The majority of patients had asymptomatic infection and were managed at home. Among those with a symptomatic infection, the most common symptoms were fever and cough. A total of 3 (13.6%) patients needed oxygen therapy, one developed multisystem inflammatory syndrome of children leading to cardiogenic shock. Three patients required intensive care or respiratory support;all the patients had favorable clinical outcomes. The median time from the onset of COVID-19 to a negative result on the reverse transcription-polymerase chain reaction test was 21.3 days. Cancer treatment was modified in 15 patients (68.2%). Conclusion(s): Our results suggest that children with hemato-oncological illnesses rarely experience severe COVID-19 disease. The impact of the first wave of COVID-19 primarily manifested as disruptions in the logistic planning and administration of essential treatment to these children rather than COVID-19 sequelae.Copyright © 2021 Cancer Research, Statistics, and Treatment Published by Wolters Kluwer - Medknow.

Analyses of kidney biomarkers in patients with sars-cov-2 (Covid-19)

The new coronavirus was first reported in China and caused a widespread global outbreak of pneumonia that spread rapidly across this country and many other countries. Acute kidney injury is one of the important complications of COVID-19, which has been shown in some cases. Exploring the diagnostic features of biomarkers of kidney function in COVID-19 patients may lead to better patient management. We collected laboratory data from 206 people with confirmed COVID-19 disease and evaluated their renal biomarkers, Blood Urea Nitrogen (BUN), and creatinine. The age range of the patients was almost 62 years old. The mean age in the dead patients and recovered patients was 71 and 54 years old, respectively. The average LDH value was 755 U/L, and creatine phosphokinase (CPK) was 267 U/L in the patients. The average BUN was 59.1 U/L, and creatinine was 1.5 U/L in COVID-2019 patients. Among all 193 patients, laboratory results revealed that 163 (85.4%) patients had an elevated BUN level. Based on creatinine levels for total patients, laboratory results revealed that 49 (25.4%) patients had an elevated value. The average BUN value in dead patients was 85 mg/dL, while in recovered patients was 40.5 mg/dL (P<0.0001). Also, the average creatinine level in dead patients was 1.86 mg/dL, while in recovered patients was 1.24 mg/dL (P=0.0004). Inflammation following COVID-19 disease causes kidney damage and elevated urea and creatinine levels, which may increase the risk of death in these patients.Copyright © 2023 Tehran University of Medical Sciences.

Predictive value of immunoglobulin G, activated partial thromboplastin time, platelet, and indirect bilirubin for delayed viral clearance in patients infected with the Omicron variant.

Background: Omicron is the recently emerged highly transmissible severe acute respiratory syndrome coronavirus 2 variant that has caused a dramatic increase in coronavirus disease-2019 infection cases worldwide. This study was to investigate the association between demographic and laboratory findings, and the duration of Omicron viral clearance. Methods: Approximately 278 Omicron cases at the Ruijin Hospital Luwan Branch, Shanghai Jiaotong University School of Medicine were retrospectively analyzed between August 11 and August 31, 2022. Demographic and laboratory data were also collected. The association between demographics, laboratory findings, and duration of Omicron viral clearance was analyzed using Pearson correlation analysis and univariate and multivariate logistic regression. Results: Univariate logistic regression analyses showed that a prolonged viral clearance time was significantly associated with older age and lower immunoglobulin (Ig) G and platelet (PLT) levels. Using multinomial logistic regression analyses, direct bilirubin, IgG, activated partial thromboplastin time (APTT), and PLT were independent factors for longer viral shedding duration. The model combining direct bilirubin, IgG, APTT, and PLT identifies patients infected with Omicron whose viral clearance time was ≥7 days with 62.7% sensitivity and 83.4% specificity. Conclusion: These findings suggest that direct bilirubin, IgG, PLT, and APTT are significant risk factors for a longer viral shedding duration in patients infected with Omicron. Measuring levels of direct bilirubin, IgG, PLT, and APTT is advantageous to identify patients infected with Omicron with longer viral shedding duration.

Use of platelet-rich plasma for COVID-19-related olfactory loss: a randomized controlled trial.

INTRODUCTION: The current study evaluated the use of platelet-rich plasma (PRP), an autologous blood product with supraphysiologic concentrations of growth factors, in the treatment of prolonged coronavirus disease 2019 (COVID-19)-related smell loss. METHODS: This multi-institutional, randomized controlled trial recruited patients with COVID-19 who had objectively measured smell loss (University of Pennsylvania Smell Identification Test [UPSIT] ≤ 33) between 6 and 12 months. Patients were randomized to three intranasal injections of either PRP or sterile saline into their olfactory clefts. The primary outcome measure was change in Sniffin' Sticks score (threshold, discrimination, and identification [TDI]) from baseline. The secondary end point measures included responder rate (achievement of a clinically significant improvement, ≥5.5 points TDI), change in individual TDI olfaction scores, and change in subjective olfaction via a visual analog scale. RESULTS: A total of 35 patients were recruited and 26 completed the study. PRP treatment resulted in a 3.67-point (95% CI: 0.05-7.29, p = 0.047) greater improvement in olfaction compared with the placebo group at 3 months and a higher response rate (57.1% vs 8.3%, odds ratio 12.5 [95% exact bootstrap confidence interval, 2.2-116.7]). There was a greater improvement in smell discrimination following PRP treatment compared with placebo but no difference in smell identification or threshold. There was no difference in subjective scores between PRP and placebo. No adverse effects were reported. CONCLUSION: Olfactory function following COVID-19 can improve spontaneously after 6 months and can improve to a greater extent with PRP injection. These data build on the promise of PRP to be a safe potential treatment option for patients with COVID-19-related smell loss, and larger-powered studies will help further assess its efficacy.

Multi-omics blood atlas reveals unique features of immune and platelet responses to SARS-CoV-2 Omicron breakthrough infection.

Although host responses to the ancestral SARS-CoV-2 strain are well described, those to the new Omicron variants are less resolved. We profiled the clinical phenomes, transcriptomes, proteomes, metabolomes, and immune repertoires of >1,000 blood cell or plasma specimens from SARS-CoV-2 Omicron patients. Using in-depth integrated multi-omics, we dissected the host response dynamics during multiple disease phases to reveal the molecular and cellular landscapes in the blood. Specifically, we detected enhanced interferon-mediated antiviral signatures of platelets in Omicron-infected patients, and platelets preferentially formed widespread aggregates with leukocytes to modulate immune cell functions. In addition, patients who were re-tested positive for viral RNA showed marked reductions in B cell receptor clones, antibody generation, and neutralizing capacity against Omicron. Finally, we developed a machine learning model that accurately predicted the probability of re-positivity in Omicron patients. Our study may inspire a paradigm shift in studying systemic diseases and emerging public health concerns.

Long-term effects of Pfizer-BioNTech COVID-19 vaccinations on platelets.

There is a global concern about the safety of COVID-19 vaccines associated with platelet function. However, their long-term effects on overall platelet activity remain poorly understood. Here we address this problem by image-based single-cell profiling and temporal monitoring of circulating platelet aggregates in the blood of healthy human subjects, before and after they received multiple Pfizer-BioNTech (BNT162b2) vaccine doses over a time span of nearly 1 year. Results show no significant or persisting platelet aggregation trends following the vaccine doses, indicating that any effects of vaccinations on platelet turnover, platelet activation, platelet aggregation, and platelet-leukocyte interaction was insignificant.

Vaccine-induced immune thrombotic thrombocytopenia: what do we know hitherto?

Vaccine-induced immune thrombotic thrombocytopenia (VITT), also known as thrombosis with thrombocytopenia syndrome, is a catastrophic and life-threatening reaction to coronavirus disease 2019 (COVID-19) vaccines, which occurs disproportionately in response to vaccination with non-replicating adenovirus vector (AV) vaccines. The mechanism of VITT is not well defined and it has not been resolved why cases of VITT are predominated by vaccination with AV vaccines. However, virtually all VITT patients have positive platelet-activating anti-platelet factor 4 (PF4) antibody titers. Subsequently, platelets are activated and depleted in an Fcγ-receptor IIa (FcγRIIa or CD32a)-dependent manner, but it is not clear why or how the anti-PF4 response is mounted. This review describes the pathogenesis of VITT and provides insight into possible mechanisms that prompt the formation of a PF4/polyanion complex, which drives VITT pathology, as an amalgam of current experimental data or hypotheses.

Platelet-monocyte aggregates: molecular mediators of thromboinflammation.

Platelets, key facilitators of primary hemostasis and thrombosis, have emerged as crucial cellular mediators of innate immunity and inflammation. Exemplified by their ability to alter the phenotype and function of monocytes, activated platelets bind to circulating monocytes to form monocyte-platelet aggregates (MPA). The platelet-monocyte axis has emerged as a key mechanism connecting thrombosis and inflammation. MPA are elevated across the spectrum of inflammatory and autoimmune disorders, including cardiovascular disease, systemic lupus erythematosus (SLE), and COVID-19, and are positively associated with disease severity. These clinical disorders are all characterized by an increased risk of thromboembolic complications. Intriguingly, monocytes in contact with platelets become proinflammatory and procoagulant, highlighting that this interaction is a central element of thromboinflammation.