Acute Tubular Necrosis (ATN)

Acute tubular necrosis is a form of intrinsic acute kidney injury (AKI) involving injury to renal tubular epithelial cells. The tubules are the working part of the nephron: after the glomerulus filters the blood, tubular cells reclaim sodium and water, excrete potassium and acid, and concentrate the urine. Those jobs depend on active transport, which needs a constant supply of oxygen and energy. When oxygen delivery falls or a toxin reaches the cell, the transport work fails first, and everything that depends on it follows. The term acute tubular injury is often more accurate because extensive tubular cell necrosis is not present in every case. Frank necrosis is only one of the patterns seen on kidney tissue, and many patients have severe kidney dysfunction with limited structural damage. The practical point for the nurse is that the injury is defined by loss of function, not by a dead kidney, so recovery is possible and worth protecting. ### Major causes Major causes are prolonged kidney hypoperfusion, septic shock, nephrotoxic medications, pigment-associated kidney injury and selected toxic exposures. ### Clinical manifestations Clinical...