Prognostic value of SOFA combined with chest CT severity score in patients with critical COVID-19 pneumonia: a retrospective study (preprint)

Background: Either sequential organ failure assessment (SOFA) score or chest CT severity score (CT-SS) is often used alone to evaluate the prognosis of patients with critical coronavirus disease 2019 (COVID-19), but each of them has intrinsic deficiency. Herein, we attempted to investigate the predictive value of the combination of SOFA and CT-SS for the prognosis of COVID-19. Materials and Methods: A single-center retrospective study was performed in the Second Affiliated Hospital of Zhejiang University School of Medicine from December 2022 to January 2023. Patients with critical COVID-19 pneumonia were divided into two groups of survival or non-survival of hospitalization. The data including clinical characteristics, CT-SS, SOFA score, laboratory results on admission day were collected and analyzed. In addition, the predictive value of SOFAscore, chest CT-SS, or their combination for in-hospital mortality of COVID-19 pneumonia were compared by receiver operating characteristic (ROC) curve. Results: A total of 424 patients with a mean age of 75.46 years and a major proportion of male (69.10%) were finally enrolled, and the total in-hospital mortality was 43.40% (184/424). In comparison with survival group, significant higher proportions of older age (>75 years), comorbidities including obesity, diabetes, and cerebrovascular disease, more needs of mechanical ventilation and continuous renal replacement therapy (CRRT) were observed in the non-survival group (all P﹤0.05). In addition, non-survival patients had a higher value of creatinine, procalcitonin, C-reactive protein, interleukin-6 , SOFA score , CT-SS  (all P﹤0.05) on admission day. Multivariate logistic regression analysis further showed that older age, obesity, diabetes, SOFA score, CT-SS, mechanical ventilation, and lymphocytopenia (all P﹤0.05) were independently related with in-hospital mortality. Moreover, the area under the curve (AUC) of combination of SOFA score and chest CT-SS became significant higher than their respective alone (P＜0.01). Conclusion: A simple combination of SOFA scorewith chest CT-SS on admission elicits a better predictive value for in-hospital mortality of critical COVID-19 patients, which could also serve as a promising indicator for prognosis prediction of other severe lung diseases like severe pneumonia and acute lung injury.

Targeting G9a translational mechanism of SARS-CoV-2 pathogenesis for multifaceted therapeutics of COVID-19 and its sequalae (preprint)

By largely unknown mechanism(s), SARS-CoV-2 hijacks the host translation apparatus to promote COVID-19 pathogenesis. We report that the histone methyltransferase G9a noncanonically regulates viral hijacking of the translation machinery to bring about COVID-19 symptoms of hyperinflammation, lymphopenia, and blood coagulation. Chemoproteomic analysis of COVID-19 patient peripheral mononuclear blood cells (PBMC) identified enhanced interactions between SARS-CoV-2-upregulated G9a and distinct translation regulators, particularly the N6-methyladenosine (m6A) RNA methylase METTL3. These interactions with translation regulators implicated G9a in translational regulation of COVID-19. Inhibition of G9a activity suppressed SARS-CoV-2 replication in human alveolar epithelial cells. Accordingly, multi-omics analysis of the same alveolar cells identified SARS-CoV-2-induced changes at the transcriptional, m6A-epitranscriptional, translational, and post-translational (phosphorylation or secretion) levels that were reversed by inhibitor treatment. As suggested by the aforesaid chemoproteomic analysis, these multi-omics-correlated changes revealed a G9a-regulated translational mechanism of COVID-19 pathogenesis in which G9a directs translation of viral and host proteins associated with SARS-CoV-2 replication and with dysregulation of host response. Comparison of proteomic analyses of G9a inhibitor-treated, SARS-CoV-2 infected cells, or ex vivo culture of patient PBMCs, with COVID-19 patient data revealed that G9a inhibition reversed the patient proteomic landscape that correlated with COVID-19 pathology/symptoms. These data also indicated that the G9a-regulated, inhibitor-reversed, translational mechanism outperformed G9a-transcriptional suppression to ultimately determine COVID-19 pathogenesis and to define the inhibitor action, from which biomarkers of serve symptom vulnerability were mechanistically derived. This cell line-to-patient conservation of G9a-translated, COVID-19 proteome suggests that G9a inhibitors can be used to treat patients with COVID-19, particularly patients with long-lasting COVID-19 sequelae.

Personalized Assessment of Mortality Risk and Hospital Stay Duration in Hospitalized Patients with COVID-19 Treated with Remdesivir: A Machine Learning Approach (preprint)

Despite widespread vaccination, early treatments, and improved understanding of the disease, the effects of SARS-CoV-2 infection remain significant worldwide. Many patients still suffer from severe COVID-19, necessitating admission to intensive care units. Remdesivir is a primary treatment option among viral RNA polymerase inhibitors for hospitalized SARS-CoV-2 patients. However, there is a lack of studies examining factors influencing its effectiveness in this context. We conducted a retrospective study throughout 2022, analyzing clinical, laboratory, and sociodemographic data from 252 hospitalized COVID-19 patients treated with remdesivir. Six machine learning algorithms were compared and validated to predict factors associated with the loss of clinical benefit from remdesivir in terms of mortality and hospital stay. Data were extracted from electronic health records. The eXtreme Gradient Boost (XGB) method achieved the highest balanced accuracy for both mortality (95.45%) and hospital stay (94.24%). Factors associated with worse outcomes of remdesivir use in terms of mortality included limitation of life support treatment, need for ventilatory support (especially invasive mechanical ventilation) on day 14 after the first dose of remdesivir, lymphopenia, low levels of albumin and hemoglobin, presence of flu and/or coinfection, and cough. Factors associated with worse outcomes of remdesivir use in terms of hospital stay included the number of doses of the COVID-19 vaccine, patchy lung density, bilateral pulmonary radiological status, number of comorbidities, oxygen therapy, troponin and lactate dehydrogenase levels, and asthenia. These findings highlight the effectiveness of XGB as a strong candidate for accurately categorizing COVID-19 patients undergoing remdesivir treatment.

A genetically modulated Toll-like-receptor-tolerant phenotype in peripheral blood cells of children with multisystem inflammatory syndrome. (preprint)

Dysregulated innate immune responses contribute to multisystem inflammatory syndrome in children (MIS-C), characterized by gastrointestinal, mucocutaneous, and/or cardiovascular injury occurring weeks after SARS-CoV-2 exposure. To investigate innate immune functions in MIS-C, we stimulated ex vivo peripheral blood cells from MIS-C patients with agonists of Toll-like receptors (TLR), key innate immune response initiators. We found severely dampened cytokine responses and elevated gene expression of negative regulators of TLR signaling. Increased plasma levels of zonulin, a gut leakage marker, were also detected. These effects were also observed in children enrolled months after MIS-C recovery. Moreover, cells from MIS-C children carrying rare genetic variants of lysosomal trafficking regulator (LYST) were less refractory to TLR stimulation and exhibited lysosomal and mitochondrial abnormalities with altered energy metabolism. Our results strongly suggest that MIS-C hyperinflammation and/or excessive or prolonged stimulation with gut-originated TLR ligands drive immune cells to a lasting refractory state. TLR hyporesponsiveness is likely beneficial, as suggested by excess lymphopenia among rare LYST variant carriers. Our findings point to cellular mechanisms underlying TLR hyporesponsiveness; identify genetic determinants that may explain the MIS-C clinical spectrum; suggest potential associations between innate refractory states and long COVID; and highlight the need to monitor long-term consequences of MIS-C.

Clinical, laboratory, and imaging findings of stage 3-5 chronic kidney disease patients suffering from COVID-19 in Bangladesh: a prospective cross-sectional study (preprint)

Background: Chronic kidney disease (CKD) patients were susceptible to morbidity and mortality once they affected by COVID-19. These patients were more likely to develop severe disease, requiring dialysis, admission to intensive care unit. The aim of this study was to evaluate the presentations and outcomes of COVID-19 in stage 3-5 CKD patients not on dialysis. Methods This prospective observational study was conducted in the COVID-19 unit, at Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka from September 2020 to August 2021. Hospitalized RT-PCR positive COVID-19 patients with pre-existing CKD having eGFR <60 ml/min/1.73 m 2 but not yet on dialysis were enrolled. Clinical and laboratory parameters were recorded. Outcomes were observed till discharge from the hospital and followed up after 3 months of survived patients. Results Out of 109 patients, the mean age was 58.1(SD: 15.4) years where 61.5% were male. Common co-morbid conditions were hypertension (89.0%), diabetes mellitus (58.7%) and ischemic heart disease (24.8%). Fever, cough, shortness of breath and fatigue were common presenting features. Most of the patients had moderate (41.3%) and severe (41.3%) COVID-19. Sixty-six patients (60.6%) developed AKI on CKD. Twenty patients (30.3%) required dialysis. Death occurred in 16 patients (14.7%) and 12 patients (11%) required ICU admission and 6 patients (9.1%) achieved baseline renal function at discharge. We identified risk factors like low haemoglobin, lymphopenia, high CRP, high procalcitonin, high LDH and low SpO 2 in patients who did not survive. Seventy-six patients were followed up at 3rd month where 17 patients were lost. Ten patients (27.0%) achieved baseline renal function who had persistent AKI at discharge and 34 patients (87.1%) remained stable who had stable renal function at discharge. Conclusion The stage 3-5 chronic kidney patients with COVID-19 are vulnerable to severe to critical morbidity and mortality with higher incidence of AKI which demands a special attention to this group of patients.

Assessment of longitudinal changes in immune responses in critically ill adults with COVID-19 (preprint)

Clinically, COVID-19 is often a mild or asymptomatic illness. However, in a subset of patients, a more severe illness with one or more organ dysfunction requiring intensive care (ICU) admission occurs (stated as critical COVID-19). Most studies assessing the immune responses in COVID-19 focus on patients with non-critical COVID-19, often assessing single biological domain (such as cytokines, leukocytes, proteomics, or transcriptomics) at single time point in patient’s illness. In this context, our cohort study of patients with critical COVID-19 with demographically similar pre-pandemic controls, characterised the longitudinal changes in multiple biological domains (28 plasma cytokines, 30 immune cell subsets identified using mass cytometry and pan-leukocyte transcriptome) at four clinically relevant timepoints between ICU admission and discharge. When compared with controls, on ICU admission day, patients with critical COVID-19, had altered cytokine/chemokine profile (high interleukin-6 (IL-6), IL-10, IL-13, CXCL10, with low CCL17, and CXCL5)), raised histones (H3.1, H3R8), robust plasmablast response despite lymphopenia, with enrichment of immunoglobulin production and interferon pathways in the transcriptome. Analyses of longitudinal transcriptome data highlights three immunologically distinct clusters that were discordant to clinical time points, indicating that the clinical time points do capture immune response trajectory. Complete integration of this multi-domain longitudinal data indicated that ~ 70% of immunological heterogeneity is explained by the transcriptome.

IFIH1 loss-of-function predisposes to inflammatory and SARS-CoV-2-related infectious diseases (preprint)

The IFIH1 gene, encoding melanoma differentiation-associated protein 5 (MDA5), is an indispensable innate immune regulator involved in the early detection of viral infections. Previous studies described MDA5 dysregulation linking it to weakened immunological responses, and increased susceptibility to microbial infections and autoimmune disorders. Monoallelic gain-of-function of the IFIH1 gene has been associated with multisystem disorders, namely Aicardi-Goutieres and Singleton-Merten syndromes, while biallelic loss of this gene causes immunodeficiency. In this study, nine patients suffering from different cases of recurrent infections, inflammatory diseases, severe COVID-19, or multisystem inflammatory syndrome in children (MIS-C) were identified with putative loss-of-function IFIH1 variants by whole exome sequencing. All patients revealed signs of lymphopenia and an increase in inflammatory markers, including CRP, amyloid A, ferritin, and IL-6. One patient with a pathogenic homozygous variant c.2807+1G>A was the most severe case showing immunodeficiency and glomerulonephritis. The c.1641+1G>C variant was identified in the heterozygous state in patients suffering from periodic fever, COVID-19, or MIS-C, while the c.2016delA variant was identified in two patients with inflammatory bowel disease or MIS-C. Expression analysis showed that PBMCs of one patient with a c.2016delA variant had a significant decrease in ISG15, IFNA and IFNG transcript levels, compared to normal PBMCs, upon stimulation with poly(I:C), suggesting that MDA5 receptor truncation disrupts the immune response. Our findings accentuate the implication of rare monogenic IFIH1 loss-of-function variants in altering the immune response, and severely predisposing patients to inflammatory and infectious diseases, including SARS-CoV-2 related disorders.

The Role of the Immune System on the Cardiac Complications Observed in SARS-CoV-2

Abstract An acute respiratory syndrome caused by SARS-CoV2 was declared a pandemic by the World Health Organization. Current data in the world and in Brazil show that approximately 40% of patients who died have some type of cardiac comorbidity. There are also robust reports showing an increase in IL-6 / IL-1B / TNF-alpha and the presence of lymphopenia in patients with COVID-19. Our team and others have shown that increased cytokines are the link between arrhythmias/Left ventricular dysfunction and the immune system in different diseases. In addition, it has been well demonstrated that lymphopenia can not only be a good marker, but also a factor that causes heart failure. Thus, the present review focused on the role of the immune system upon the cardiac alterations observed in the SARS-CoV2 infection. Additionally, it was well described that SARS-CoV-2 is able to infect cardiac cells. Therefore, here it will be reviewed in deep.

Pathological Effects of SARS-CoV-19 Associated With Hematological Abnormalities (preprint)

The SARS coronavirus 2 (SARS-CoV-2) is the causative agent of the 2019 coronavirus disease (COVID-19) pandemic that has executed 6.9 million people and infected over 765 million. It’s become a major worldwide health alarm and is also known to cause abnormalities in various systems, including the hematologic system. COVID-19 infection primarily affects the lower res-piratory tract and can lead to a cascade of events, including a cytokine storm, intravascular thrombosis, and subsequent complications such as arterial and venous thromboses. COVID-19 can cause thrombocytopenia, lymphopenia, and neutrophilia, which are associated with worse out-comes. Prophylactic anticoagulation is essential to prevent complication and death rate associated with the virus's effect on the coagulation system. It is crucial to recognize these complications early and promptly start therapeutic anticoagulation to improve patient outcomes. While rare, COVID-19-induced disseminated intravascular coagulation exhibits some similarities to DIC induced by sepsis. LDH, D-dimer, ferritin, and CRP biomarker are often increase in serious COVID-19 cases and poor prognosis. Understanding the pathophysiology of the disease and identifying risk factors for adverse outcomes is critical for effective management of COVID-19.

The shed P2X7 receptor is an index of adverse clinical outcome in COVID-19 patients.

Introduction: The pathophysiology of the Corona Virus Disease 2019 (COVID-19) is incompletely known. A robust inflammatory response caused by viral replication is a main cause of the acute lung and multiorgan injury observed in critical patients. Inflammasomes are likely players in COVID-19 pathogenesis. The P2X7 receptor (P2X7R), a plasma membrane ATP-gated ion channel, is a main activator of the NLRP3 inflammasome, of the ensuing release of inflammatory cytokines and of cell death by pyroptosis. The P2X7R has been implicated in COVID-19-dependent hyperinflammation and in the associated multiorgan damage. Shed P2X7R (sP2X7R) and shed NLRP3 (sNLRP3) have been detected in plasma and other body fluids, especially during infection and inflammation. Methods: Blood samples from 96 patients with confirmed SARS-CoV-2 infection with various degrees of disease severity were tested at the time of diagnosis at hospital admission. Standard haematological parameters and IL-6, IL-10, IL-1ß, sP2X7R and sNLRP3 levels were measured, compared to reference values, statistically validated, and correlated to clinical outcome. Results: Most COVID-19 patients included in this study had lymphopenia, eosinopenia, neutrophilia, increased inflammatory and coagulation indexes, and augmented sNLRP3, IL-6 and IL-10 levels. Blood concentration of sP2X7R was also increased, and significantly positively correlated with lymphopenia, procalcitonin (PCT), IL-10, and alanine transaminase (ALT). Patients with increased sP2X7R levels at diagnosis also showed fever and respiratory symptoms, were more often transferred to Pneumology division, required mechanical ventilation, and had a higher likelihood to die during hospitalization. Conclusion: Blood sP2X7R was elevated in the early phases of COVID-19 and predicted an adverse clinical outcome. It is suggested that sP2X7R might be a useful marker of disease progression.

Predictors of mortality in hemodialysis patients with COVID-19: A single-center experience.

INTRODUCTION: The COVID-19 pandemic has disproportionately affected patients with preexisting comorbidities, particularly dialysis patients. The aim of this study was to determine predictors of mortality in this population. METHODOLOGY: We conducted an observational, retrospective, cohort study collecting data from pre and post-vaccine from the electronic medical records of a single dialysis center at Hygeia International Hospital Tirana, Albania. RESULTS: Of 170 dialysis patients, 52 were diagnosed with COVID-19. The prevalence of COVID-19 infection in our study was 30.5%. The mean age was 61.5 ± 12.3 years and 65.4% were men. The mortality rate in our cohort was 19.2%. Mortality rates were higher in patients with diabetic nephropathy (p < 0.04) and peripheral vascular disease (p < 0.01). Elevated C- reactive protein (CRP) (p < 0.018), high red blood cell distribution width (RDW) (p < 0.03), and low lymphocyte and eosinophil counts, were found to be risk factors for severe COVID-19 disease. ROC analysis identified lymphopenia and eosinopenia as the strongest predictors of mortality. After the vaccine administration, the mortality rate in the vaccinated population was 8%, in contrast to the 66.7% mortality rate that was found in the unvaccinated group (p < 0.001). CONCLUSIONS: Our study revealed that risk factors for the development of severe COVID-19 infection were RDW, low lymphocyte and eosinophil counts, elevated levels of CRP. Lymphopenia and eosinopenia were determined as the most important predictors of mortality, in our cohort. Mortality was notably lower among vaccinated patients.

Reappraisal of Idiopathic CD4 Lymphocytopenia at 30 Years.

BACKGROUND: Idiopathic CD4 lymphocytopenia (ICL) is a clinical syndrome that is defined by CD4 lymphopenia of less than 300 cells per cubic millimeter in the absence of any primary or acquired cause of immunodeficiency. Some 30 years after its original identification, ICL has remained a disease of obscure cause, with limited evidence with respect to its prognosis or management, despite diagnostic and therapeutic innovations. METHODS: We evaluated the clinical, genetic, immunologic, and prognostic characteristics of 108 patients who were enrolled during an 11-year period. We performed whole-exome and targeted gene sequencing to identify genetic causes of lymphopenia. We also performed longitudinal linear mixed-model analyses of T-cell count trajectories and evaluated predictors of clinical events, the response to immunization against coronavirus disease 2019 (Covid-19), and mortality. RESULTS: After the exclusion of patients with genetic and acquired causes of CD4 lymphopenia, the study population included 91 patients with ICL during 374 person-years of follow-up. The median CD4+ T-cell count among the patients was 80 cells per cubic millimeter. The most prevalent opportunistic infections were diseases related to human papillomavirus (in 29%), cryptococcosis (in 24%), molluscum contagiosum (in 9%), and nontuberculous mycobacterial diseases (in 5%). A reduced CD4 count (<100 cells per cubic millimeter), as compared with a CD4 count of 101 to 300 cells, was associated with a higher risk of opportunistic infection (odds ratio, 5.3; 95% confidence interval [CI], 2.8 to 10.7) and invasive cancer (odds ratio, 2.1; 95% CI, 1.1 to 4.3) and a lower risk of autoimmunity (odds ratio, 0.5; 95% CI, 0.2 to 0.9). The risk of death was similar to that in the age- and sex-adjusted general population, but the prevalence of cancer was higher. CONCLUSIONS: Among the study patients, ICL continued to be associated with increased susceptibility to viral, encapsulated fungal, and mycobacterial diseases, as well as with a reduced response to novel antigens and an increased risk of cancer. (Funded by the National Institute of Allergy and Infectious Diseases and the National Cancer Institute; ClinicalTrials.gov number, NCT00867269.).

Kinetics of cellular and humoral immunogenicity and effectiveness of SARS-CoV-2 booster vaccination in hematologic neoplasms.

Data on the effect of booster SARS-CoV-2 vaccination are mainly focused on humoral immunogenicity, while the kinetics of vaccine-induced cellular response and its correlation with effectiveness in hematologic patients are less explored. Our aim was to evaluate the longitudinal cellular and humoral immunogenicity induced by two and three doses of the mRNA-1273 SARS-CoV-2 vaccine in 270 patients with hematologic malignancies, and its relationship with the severity of breakthrough SARS-CoV-2 infection. Results indicate that at 23 weeks after the second dose, the seroconversion rate declined from 68.5% to 59.3%, with a reduction in median anti-S titers from 1577 to 456 BAU/mL, mainly in patients over 65 years of age or chronic lymphocytic leukemia (CLL) patients undergoing active therapy. Cellular immunogenicity, however, remained positive in 84.4% of cases. A third vaccine dose seroconverted 42.7% (41/96) and triggered cellular response in 36.7% (11/30) of previously negative patients. Notably, only 7.2% (15/209) of patients failed to develop both humoral and cellular response. Active therapy, anti-CD20 antibodies, lymphopenia, hypogammaglobulinemia, and low CD19+ cell count were associated with poor humoral response, while active disease, GvHD immunosuppressive therapy, lymphopenia, and low CD3+ , CD4+ , CD56+ cell count determined an impaired cellular response. After 13.8 months of follow-up, the incidence of SARS-CoV-2 infection was 24.8% (67/270), including 6 (9%) severe/critical cases associated with a weaker cellular (median interferon gamma (IFN-γ) 0.19 vs. 0.35 IU/mL) and humoral response (median anti-S titer <4.81 vs. 788 BAU/mL) than asymptomatic/mild cases. In conclusion, SARS-CoV-2 booster vaccination improves humoral response and COVID-19 severity is associated with impaired vaccine-induced immunogenicity.

Viral infection of hematopoietic stem cells (preprint)

Hematopoietic stem cells (HSCs) are critical for maintaining healthy blood and immune cell populations. They’re also valuable resources and targets for medical treatments, such as HSC transplantation and gene therapy. However, these blood cell precursors are susceptible to viral infection, which can cause blood disorders and limit the efficacy of HSC-based therapies. In fact, viral infection is a leading cause of complications and death among HSC transplant recipients. For example, latent cytomegalovirus can become reactivated after transplantation leading to immunosuppression, pneumonia, encephalitis, and graft failure. HSC transplantation also reduces the numbers of T cells that are specifically cytotoxic toward the mononucleosis- inducing Epstein–Barr virus. Furthermore, recipients of HSC transplants are more susceptible to infection by SARS-CoV-2, the cause of the COVID-19 pandemic. SARS-CoV-2, in turn, can induce numerous blood abnormalities, such as thrombocytopenia, lymphocytopenia, anemia, hypercoagulability, and systemic thrombosis in part because HSCs express SARS-CoV-2 receptors. More research is needed to determine the best ways to prevent viral infection of these essential cells in both endogenous and transplantation contexts, in order to reduce serious blood disorders and related mortality in the clinic.

The unreversible reduced but persistent activated NK and CD8+ T cells in severe/critical COVID-19 during omicron pandemic in China.

As a hallmark of COVID-19 progression, lymphopenia alongside its subtle immune disturbance has been widely reported, but yet to be thoroughly elucidated. Aiming at exploring clinical immune biomarkers with accessibility in the current and acute omicron epidemic abrupted in China post-control era, we design a real-world prospective observation cohort in Peking Union Medical College Hospital to describe immunological, haematological profiles inducing lymphocyte subsets related to SARS-CoV-2 infection. In this COVID-19 cohort, we enrolled 17 mild/moderate (M/M), 24 severe (S) and 25 critical (C) patients. The dynamics of lymphocytes of COVID-19 demonstrated that the sharp decline of NK, CD8+, and CD4+ T cell counts was the main contributor to lymphopenia in the S/C group, compared to the M/M group. Expressions of activation marker CD38 and proliferation marker Ki-67 both in CD8+ T and NK cells were significantly higher in all COVID-19 patients than that in healthy donors, independent of disease severity. The subsequent analysis showed in contrast to the M/M group, NK and CD8+ T cell counts remained low-level after therapy in the S/C group. CD38 and Ki-67 expressions in NK and CD8+ T cells still stay at a high level, despite active treatment. Targeting relatively elderly patients with SARS-CoV-2 infection, severe COVID-19 features the unreversible reduction of NK and CD8+ T cells with persistent activation and proliferation, which assist clinicians in early recognizing and saving severe or critical COVID-19 patients. Given that immunophenotype, the new immunotherapy improving NK and CD8+ T lymphocyte antiviral efficiency should be considered.

The Role of Lymphocyte Subsets, PD-1, and FAS (CD95) in COVID-19 Cancer Patients.

Lymphocytes are the main orchestrators that regulate the immune response in SARS-COV-2 infection. The exhaustion of T lymphocytes is a contributing factor to lymphopenia, which is responsible for the COVID-19 adverse outcome. However, it is still not demonstrated on a large scale, including cancer patients. Peripheral blood samples were obtained from 83 SARS-CoV2 infected cancer patients, and 29 COVID-19 infected noncancer patients compared to 28 age-matched healthy controls. Lymphocyte subsets were assessed for CD3, CD4, CD8, CD56, PD-1, and CD95 using flow cytometry. The data were correlated to the patients' clinical features, COVID-19 severity and outcomes. Lymphopenia, and decreased CD4+ T cells and CD8+ T cells were significantly observed in COVID-19 cancer and noncancer patients compared to the control group (p < 0.001, for all). There was a significantly increased expression of CD95 and PD-1 on the NK cells, CD4+ T cells, and CD8+ T cells in COVID-19 cancer and noncancer patients in comparison to the control group. The increased expression of CD95 on CD8+ T cells, as well as the increased expression of PD-1 on CD8+ T cells and NK cells are significantly associated with the severity of COVID-19 infection in cancer patients. The increased expression of CD95 and PD-1 on the CD4+ T cells, CD8+ T cells, and NK cells was observed significantly in nonsurviving patients and those who were admitted to the intensive care unit in COVID-19 cancer and noncancer patients. The increased expression of PD-1 and CD95 could be possible prognostic factors for COVID-19 severity and adverse outcomes in COVID-19 cancer and noncancer patients.

Initial Observations of COVID-19 in US Children.

Coronavirus disease (COVID-19) has affected children differently from adults worldwide. Data on the clinical presentation of the infection in children are limited. We present a detailed account of pediatric inpatients infected with severe acute respiratory syndrome coronavirus 2 virus at our institution during widespread local transmission, aiming to understand disease presentation and outcomes. A retrospective chart review was performed of children, ages 0 to 18 years, with a positive polymerase chain reaction test for severe acute respiratory syndrome coronavirus 2 on nasopharyngeal specimens admitted to our hospital over a 4-week period. We present clinical data from 22 patients and highlight the variability of the presentation. In our study, most children presented without respiratory illness or symptoms suggestive of COVID-19; many were identified only because of universal testing. Because children may have variable signs and symptoms of COVID-19 infection, targeted testing may miss some cases.

Haematological changes in sailors who had COVID-19.

BACKGROUND: Follow-up of patients who had coronavirus disease 2019 (COVID-19) proves that clinical symptoms persist for months after recovery. A complex of such persistent manifestations is defined as the post-COVID-19 syndrome. One of the criteria for post-COVID-19 syndrome may be typical changes in white blood cell count and white blood cell (WBC) differential. The aim of the work is to study the frequency of haematological changes in sailors who had the acute coronavirus infection. MATERIALS AND METHODS: The retrospective study covered 30 candidate sailors aged 21 to 60 years with a history of COVID-19 and persistent changes in the WBC count and WBC differential and who did not have haematological abnormalities during the previous medical examinations. RESULTS: Analysis of WBC and WBC count at the long-term period after COVID-19 confirmed persistent changes in the form of neutrophilia, lymphopenia, changes in the neutrophils and lymphocytes ratio. The revealed changes in the WBC count were typical and fit into several patterns: A. Absolute leukocytosis, absolute and relative neutrophilia, relative lymphopenia; B. Relative and absolute lymphopenia, relative neutrophilia; C. Relative and absolute lymphocytosis, relative neutropenia; D. Relative lymphopenia, without other changes in WBC differential. CONCLUSIONS: The most typical laboratory change in WBC count in patients with the past COVID-19 is relative or absolute leukopenia. Persistent changes in WBC count are not always outside of the reference range for absolute values and should be assessed by a complex of typical changes. The presence of typical changes in WBC count in a patient with the past COVID-19 requires a profound examination for the post-COVID-19 syndrome.