Considering COVID-19 kidney injury

Does SARS-CoV-2 infection have long-term effects on the kidney? SARS-CoV2 infection and the associated clinical disease, coronavirus disease-19 (COVID-19), have resulted in more than 20 million infections worldwide with an overall mortality rate of 3.9%. Initially thought to be a disease of the respiratory system, the clinical syndrome of COVID-19 is actually multifaceted, also affecting the heart, vasculature, and neurological system. Acute kidney injury (AKI) is a common complication, affecting up to 40% of patients hospitalized with COVID-19, with 20% of these patients needing acute hemodialysis. Along with the shortage of ventilators that has been amply discussed, hospitals suffered from an acute shortage of dialysis machines during case surges. Although the epidemiology of in-hospital AKI has been shown before in reports from China, Europe, and the United States of America, Fisher et al. delved deeper into the effects of COVID-19 on the kidney. They retrospectively evaluated AKI incidence, risk factors, and outcomes for hospitalized adult patients with and without COVID-19 in a large New York City health system. They showed increased AKI incidence, greater need for acute dialysis, and higher mortality in those with COVID-19. They also identified several factors that were significantly associated with AKI, regardless of COVID-19 status. Critically, they also assessed how many individuals recovered kidney function during hospitalization after an AKI episode. Only 42% of patients with COVID-19 and AKI recovered baseline kidney function compared to 70% without COVID-19. Considering the substantial evidence linking in-hospital AKI, and more importantly, non-recovery of kidney function after an acute episode, with long-term mortality and worse kidney function, this may herald the onset of a coming post-COVID kidney disease epidemic. This may be worsened by the fact that regular physician visits have decreased during this pandemic, and as a result, many patients with chronic disease may not be monitored regularly. Although the research and medical community's focus has been on the acute care of patients with COVID-19, the long-term effects of infection are slowly coming into focus. Integrated research and clinical care approaches are urgently needed to better understand and address what is likely to be a growing at-risk population.