Uremia

Uremia is a clinical syndrome that results from the accumulation of waste products in the blood due to severe kidney dysfunction. It most commonly occurs in advanced chronic kidney disease or after acute kidney injury that progresses to end-stage kidney disease, when the glomerular filtration rate falls markedly. Retained solutes include urea, creatinine, uric acid and other nitrogenous and gut-derived toxins, along with metabolic disturbances such as metabolic acidosis, electrolyte abnormalities (notably hyperkalemia and hyperphosphatemia, with hypocalcemia) and fluid overload. These changes contribute to a wide range of systemic effects.

Clinically, uremia presents with nonspecific symptoms such as fatigue, weakness, anorexia, nausea and vomiting, and pruritus. Cognitive changes, sleep disturbances, and altered mental status can occur, especially in advanced disease. Platelet dysfunction may lead to bleeding, and pericarditis is a known life-threatening complication. Diagnosis is based on signs and symptoms of uremia in the setting of azotemia, with laboratory evidence of elevated blood urea nitrogen and creatinine and associated electrolyte and acid-base disturbances.

Management aims to remove toxins and correct metabolic abnormalities. Initiation of dialysis is indicated for life-threatening uremic complications, severe acidosis, refractory hyperkalemia, or fluid overload. Dialysis modalities include intermittent hemodialysis and peritoneal dialysis. In the long term, management of chronic kidney disease includes blood pressure and diabetes control, phosphate management, iron supplementation and erythropoiesis-stimulating agents for anemia, dietary protein adjustment, and consideration of kidney transplantation when appropriate.

Prognosis depends on the underlying kidney disease and response to treatment. Uremia reflects advanced renal failure and carries significant morbidity; timely dialysis and, when possible, transplantation can improve outcomes but do not cure the underlying dysfunction.