What is azotemia?

Azotemia refers specifically to the accumulation of nitrogenous waste products, such as urea and creatinine, in the bloodstream. This condition typically arises when the kidneys are not functioning properly, impeding their ability to filter waste products from the blood effectively. Elevated levels of these substances can be a significant indicator of kidney dysfunction or failure, and azotemia is classified into different types, such as prerenal, renal, and postrenal, depending on the underlying cause.

The other options do not accurately define azotemia. For instance, the excessive excretion of electrolytes in urine pertains more to conditions like renal tubular acidosis or certain electrolyte imbalances and does not reflect the accumulation of waste products in the blood. The presence of blood in urine refers to hematuria, which can indicate various renal or urinary tract issues but is not related to nitrogenous waste. Lastly, although a kidney infection may lead to symptoms including fever, it does not define azotemia itself. Therefore, the definition that azotemia is the accumulation of nitrogenous waste products in the blood is appropriate and aligns with nephrology principles.