How SARS-CoV-2 might affect potassium balance via impairing epithelial sodium channels?

Severe acute respiratory syndrome coronaviruses 2 (SARS-CoV-2) is the causative agent of current coronavirus disease 2019 (COVID-19) pandemic. Electrolyte disorders particularly potassium abnormalities have been repeatedly reported as common clinical manifestations of COVID-19. Here, we discuss how SARS-CoV-2 may affect potassium balance by impairing the activity of epithelial sodium channels (ENaC). The first hypothesis could justify the incidence of hypokalemia. SARS-CoV-2 cell entry through angiotensin-converting enzyme 2 (ACE2) may enhance the activity of renin-angiotensin-aldosterone system (RAAS) classical axis and further leading to over production of aldosterone. Aldosterone is capable of enhancing the activity of ENaC and resulting in potassium loss from epithelial cells. However, type II transmembrane serine protease (TMPRSS2) is able to inhibit the ENaC, but it is utilized in the case of SARS-CoV-2 cell entry, therefore the ENaC remains activated. The second hypothesis describe the incidence of hyperkalemia based on the key role of furin. Furin is necessary for cleaving both SARS-CoV-2 spike protein and ENaC subunits. While the furin is hijacked by the virus, the decreased activity of ENaC would be expected, which causes retention of potassium ions and hyperkalemia. Given that the occurrence of hypokalemia is higher than hyperkalemia in COVID-19 patients, the first hypothesis may have greater impact on potassium levels. Further investigations are warranted to determine the exact role of ENaC in SARS-CoV-2 pathogenesis.

Epidemiology, prognosis and management of potassium disorders in Covid-19.

Coronavirus disease (Covid-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is currently the largest health crisis facing most countries. Several factors have been linked with a poor prognosis for this disease, including demographic factors, pre-existing comorbidities and laboratory parameters such as white blood cell count, D-dimer, C-reactive protein, albumin, lactate dehydrogenase, creatinine and electrolytes. Electrolyte abnormalities particularly potassium disorders are common among Covid-19 patients. Based on our pooled analysis, hypokalemia and hyperkalemia occur in 24.3% and 4.15% of Covid-19 patients, respectively. Potassium level deviation from the normal range may increase the chances of unfavorable outcomes and even death. Therefore, this article reviewed the epidemiology of potassium disorders and explained how hypokalemia and hyperkalemia are capable of deteriorating cardiac outcomes and the prognosis of Covid-19 for infected patients. The article finishes by highlighting some important considerations in the management of hypokalemia and hyperkalemia in these patients.

Immune Characteristics of Patients with Coronavirus Disease 2019 (COVID-19).

Up to now, little is known about the detailed immune profiles of COVID-19 patients from admission to discharge. In this study we retrospectively reviewed the clinical and laboratory characteristics of 18 COVID-19 patients from January 30, 2020 to February 21, 2020. These patients were divided into two groups; group 1 had a severe acute respiratory syndrome coronavirus 2 nucleic acid-positive duration for more than 15 days (n = 6) and group 2 had a nucleic acid-positive duration for less than 15 days (n = 12). Group 1 patients had lower level of peripheral blood lymphocytes (0.40 vs. 0.78 ×109/L, p = 0.024) and serum potassium (3.36 vs. 3.79 mmol/L, p = 0.043) on admission but longer hospitalization days (23.17 vs. 15.75 days, p < 0.001) compared to Group 2 patients. Moreover, baseline level of lymphocytes (r = -0.62, p = 0.006) was negatively correlated with the nucleic acid-positive duration. Additionally, lymphocytes (420.83 vs. 1100.56 /µL), T cells (232.50 vs. 706.78 /µL), CD4+ T cells (114.67 vs. 410.44 /µL), and CD8+ T cells (94.83 vs. 257.44 /µL) in the peripheral blood analyzed by flow cytometry were significantly different between Group 1and Group 2. Furthermore, there was also a negative correlation between lymphocytes (r = -0.54, p = 0.038) or T cells (r = -0.55, p = 0.034) at diagnosis and the nucleic acid-positive duration, separately. In conclusion, the patients with nucleic acid-positive ≥ 15 days had significantly decreased lymphocytes, T cell and its subsets compared to those who remained positive for less than 15 days.