COVID-19, a pandemic of severe acute respiratory syndrome caused by Coronavirus 2 (SARS-CoV-2), continues to pose diagnostic and therapeutic challenges due to its unpredictable clinical course. Prognostic biomarkers may improve care by enabling quick identification of patients who can be safely discharged home versus those who may need careful respiratory monitoring and support. MicroRNAs (miRNAs) have risen to prominence as biomarkers for many disease states and as tools to assist in medical decisions. In the present study, we aimed to examine circulating miRNAs in hospitalized COVID-19 patients and to explore their potential as biomarkers for disease severity. We studied, by quantitative PCR, the expressions of miR-21, miR-146a, miR-146b, miR-155, and miR-499 in peripheral blood. We found that mild COVID-19 patients had 2.5-fold less circulating miR-155 than healthy people, and patients with a severe COVID-19 disease had 5-fold less circulating miR-155 than healthy people. In addition, we found that miR-155 is a good predictor of COVID-19 mortality. We suggest that examining miR-155 levels in patients’ blood, upon admission to hospital, will ameliorate the care given to COVID-19 patients.

Background: Patients with congenital heart disease have higher prevalence of thyroid dysfunction due to embryonic and genetic coexistence. Marked changes in cardiac function occur secondary to alternations in thyroid hormone levels. Cardiac catheterizations or cardiac surgeries with cardiopulmonary bypass can cause abnormalities in the circulating hormones, in the absence of primary thyroid disease. Therefore, monitoring of thyroid function should be routinely performed in children with congenital heart disease. Thyroid hormone supplementation has been postulated as a possible therapeutic option; however, the therapeutic decisions should be made based on individual circumstances, symptoms, and the severity of the thyroid dysfunction. Objectives: To describe the correlation between congenital heart disease in children and thyroid dysfunction and the debate on monitoring, intervention, and treatment. Methods: PubMed, Clinical Key, and the Cochrane Library were searched using keywords relevant to congenital heart disease/surgery, cardiopulmonary bypass, thyroid hormones, sick euthyroid syndrome, and cardiac catheterization. Studies were limited to the English language and to children 0 to 18 years old. Studies in adults with important findings were reviewed as well. All clinical studies believed to have relevance were considered. All relevant studies were reviewed, and the most pertinent data were incorporated in this review. Conclusion: There is lack of significant evidence concerning treatment for thyroid dysfunction in children with a congenital cardiac diagnosis. Adequately powered studies are needed before a uniform recommendation about treatment can be made.

During pregnancy, fetal glucose production is suppressed, with rapid activation immediately postpartum. Fatty acid–binding protein 4 (FABP4) was recently demonstrated as a regulator of hepatic glucose production and systemic metabolism in animal models. Here, we studied the role of FABP4 in regulating neonatal glucose hemostasis. Serum samples were collected from pregnant women with normoglycemia or gestational diabetes at term, from the umbilical circulation, and from the newborns within 6 hours of life. The level of FABP4 was higher in the fetal versus maternal circulation, with a further rise in neonates after birth of approximately 3-fold. Neonatal FABP4 inversely correlated with blood glucose, with an approximately 10-fold increase of FABP4 in hypoglycemic neonates. When studied in mice, blood glucose of 12-hour-old WT, Fabp4 ^–/+ , and Fabp4 ^–/– littermate mice was 59 ± 13 mg/dL, 50 ± 11 mg/dL, and 43 ± 11 mg/dL, respectively. Similar to our observations in humans, FABP4 levels in WT mouse neonates were approximately 8-fold higher compared with those in adult mice. RNA sequencing of the neonatal liver suggested altered expression of multiple glucagon-regulated pathways in Fabp4 ^–/– mice. Indeed, Fabp4 ^–/– liver glycogen was inappropriately intact, despite a marked hypoglycemia, with rapid restoration of normoglycemia upon injection of recombinant FABP4. Our data suggest an important biological role for the adipokine FABP4 in the orchestrated regulation of postnatal glucose metabolism.

Background. Technological advancement may bridge gaps between long-practiced medical competencies and modern technologies. Such a domain is the application of digital stethoscopes used for physical examination in telemedicine. This study aimed to validate the level of consensus among physicians regarding the interpretation of remote, digital auscultation of heart and lung sounds. Methods. Seven specialist physicians considered both the technical quality and clinical interpretation of auscultation findings of pre-recorded heart and lung sounds of patients hospitalized in their homes. TytoCare^TM system was used as a remote, digital stethoscope. Results. In total, 140 sounds (70 heart and 70 lungs) were presented to seven specialists. The level of agreement was measured using Fleiss’ Kappa (FK) variable. Agreement relating to heart sounds reached low-to-moderate consensus: the overall technical quality (FK = 0.199), rhythm regularity (FK = 0.328), presence of murmurs (FK = 0.469), appreciation of sounds as remote (FK = 0.011), and an overall diagnosis as normal or pathologic (FK = 0.304). The interpretation of some of the lung sounds reached a higher consensus: the overall technical quality (FK = 0.169), crepitus (FK = 0.514), wheezing (FK = 0.704), bronchial sounds (FK = 0.034), and an overall diagnosis as normal or pathological (FK = 0.386). Most Fleiss’ Kappa values were in the range of “fare consensus”, while in the domains of diagnosing lung crepitus and wheezing, the values increased to the “substantial” level. Conclusions. Bio signals, as recorded auscultations of the heart and lung sounds serving the process of clinical assessment of remotely situated patients, do not achieve a high enough level of agreement between specialized physicians. These findings should serve as a catalyzer for improving the process of telemedicine-attained bio-signals and their clinical interpretation.

Thiamine is an essential component of cellular metabolism and its deficiency results in potentially life-threatening events and profound lactic acidosis through anaerobic metabolism. Acute decompensation in thiamine-deficient patients may manifest as neurologic or cardiovascular changes, with severe lactic acidosis as the presenting symptom. We describe two hematological pediatric patients with thiamine deficiency and hemodynamic instability who improved following thiamine supplements. Thiamine levels were inversely proportional to lactic acidosis; specifically, lower thiamine levels were related to higher lactate levels. We recommend that children with hematological malignancies admitted to a pediatric intensive care unit with low blood pressure and lactic acidosis should be considered for thiamine-level screening and receive supplementation accordingly.

One of the major challenges for healthcare systems during the Coronavirus-2019 (COVID-19) pandemic was the inability to successfully predict which patients would require mechanical ventilation (MV). Angiotensin-Converting Enzyme 2 (ACE2) and TransMembrane Protease Serine S1 member 2 (TMPRSS2) are enzymes that play crucial roles in SARS-CoV-2 entry into human host cells. However, their predictive value as biomarkers for risk stratification for respiratory deterioration requiring MV has not yet been evaluated. We aimed to evaluate whether serum ACE2 and TMPRSS2 levels are associated with adverse outcomes in COVID-19, and specifically the need for MV. COVID-19 patients admitted to an Israeli tertiary medical center between March--November 2020, were included. Serum samples were obtained shortly after admission (day 0) and again following one week of admission (day 7). ACE2 and TMPRSS2 concentrations were measured with ELISA. Of 72 patients included, 30 (41.6%) ultimately required MV. Serum ACE2 concentrations >7.8 ng/mL at admission were significantly associated with the need for MV (p = 0.036), inotropic support, and renal replacement therapy. In multivariate logistic regression analysis, elevated ACE2 at admission was associated with the need for MV (OR = 7.49; p = 0.014). To conclude, elevated serum ACE2 concentration early in COVID-19 illness correlates with respiratory failure necessitating mechanical ventilation. We suggest that measuring serum ACE2 at admission may be useful for predicting the risk of severe disease.