Acute kidney injury in covid 19 patients 

COVID-19 and Acute Kidney Injury: Challenges and Management - Renal and  Urology News

The ongoing pandemic of coronavirus disease 2019 (COVID-19) causes severe acute respiratory syndrome, with a high morbidity and mortality rate. However, preliminary evidence suggests that patients admitted to the hospital with COVID-19 are also undergoing acute kidney injury (AKI) and need immediate attention of experts like urologist in Lahore.


Are people with kidney disease at higher risk? 


Individuals, already suffering from chronic disorders like hypertension, diabetes and kidney disease are at higher risk when it comes to COVID-19. These individuals can have more severe illness, as their immune system is already weakened. 


How is COVID-19 causing acute kidney injury (AKI)?


AKI is the main extrapulmonary complication of COVID-19. The exact way how COVID-19 causes renal failure in hospitalized patients is not completely understood. Many studies suggest that pre-renal, intrarenal and postrenal factors are at play here, that collectively contribute to the disease pathogenesis. When renal replacement therapy becomes mandatory, the mortality rates of these patients rises. 


With COVID-19, several studies show changes in the urinary sediment, including hematuria (blood in the urine) and proteinuria (protein in the urine) along with urinary excretion of coronavirus, suggesting that there could be renal reservoir for the virus. This, in turn, could mean there is direct cellular injury from the entry of the virus, in the cells that exhibit ACE2 receptors, but there is no clear evidence yet. ACE2 receptors are expressed widely on the kidneys. 


In autopsies of COVID positive patients in China, acute tubular necrosis (ATN) was a notable renal finding. On a microscopic level, there was loss of brush border, dilatation of the tubular lumen, frank necrosis and detachment of epithelium and vacuolar degeneration. Even though ATN remains a noticeable finding, it is yet unclear if the viral infection directly causes cell death of the tubular epithelial cells. 


Three major causes of ATN include: renal ischemia—decreased blood flow to the kidneys, sepsis and nephrotoxins. In COVID-19, sepsis is considered a major cause of AKI. Sepsis in COVID-19 can cause narrowing of the renal blood vessels, severe hypotension, damage to the kidney tubules along with an influx of inflammatory cells into the parenchyma of the kidneys. 


Other cases have reported collapsing focal segmental glomerulosclerosis (FSGS) causing nephrotic syndrome. 


What are the statistics saying?


According to research, acute kidney injury (AKI) is reported in up to 25 percent of those infected with COVID-19, particularly those with underlying comorbid conditions. In this setting, AKI is causing high mortality. 


In COVID-19 patients admitted to the intensive care (ICU), about 2.9 to 23 percent are seeing renal complications, while AKI was seen in 0.5 to 7 percent of the total cases. 


An Italian study with over 2000 admitted patients with COVID-19 saw an incidence rate of 27.8 percent of acute kidney injury. Similarly, a prospective cohort study in China of 700 admitted patients of COVID-19, found that 26.7 percent of patients presented with hematuria (blood in urine) on admission, while 5.1 percent developed acute kidney injury during their hospital stay. 


According to another observational study, respiratory failure was strongly associated with acute kidney injury. In patients with mechanical ventilation 89.7 percent developed AKI, compared to only 21.7 percent of the non-ventilated patients. Thus, the high incidence of AKI associated with COVID-19 warrants examination by a specialist like urologist in Karachi.