Hyponatremia and SARS-CoV-2 infection: A narrative review

A novel rapid spreading and changing virus called SARS-CoV-2 appeared in Wuhan city in December 2019. It was announced by the World Health Organization (WHO) as a pandemic disease in March 2020. It commonly presents with respiratory symptoms; however, it may be asymptomatic. Electrolyte abnormalities are not uncommon features of SARS-CoV-2 infection. Hyponatremia is one of these electrolyte disturbances among SARS-CoV-2 patients, and it may produce symptoms such as weakness and seizure as the initial presenting symptoms. The underlying mechanism(s) of hyponatremia due to SARS-CoV-2 infection is (are) not established. The aim of this review is to evaluate the possible mechanism of hyponatremia in patients with COVID-19. Understanding and categorizing the hyponatremia in these patients will lead to better treatment and correction of the hyponatremia. A review of the literature between December 2019 and March 2022 was conducted searching for the possible reported mechanism(s) of hyponatremia in SARS-CoV-2. Although SIADH is the commonly reported cause of hyponatremia in SARS-CoV-2 infection, other causes such as diarrhea, vomiting, and kidney salt loss must be considered before SIADH.