What is the most common cause of acute kidney injury in hospitalized patients?

Acute tubular necrosis (ATN) is recognized as the most common cause of acute kidney injury (AKI) in hospitalized patients due to its prevalence related to various clinical scenarios that often arise in the hospital setting. ATN typically occurs as a result of ischemic or nephrotoxic injuries to the renal tubules, which can happen in several situations such as prolonged hypotension, sepsis, or exposure to nephrotoxic agents like certain medications or contrast dye used in imaging studies.

In contrast, other conditions listed, while they can cause AKI, are less common. Glomerulonephritis usually involves immune-mediated processes and is not as prevalent as ATN in the acute setting of hospitalized patients. Urinary obstruction, while significant, tends to be less frequent compared to the direct tubule injury seen in ATN. Atheroembolic disease is also a recognized cause of AKI, particularly in patients with atherosclerosis, but it occurs less frequently compared to the high incidence of ATN associated with inpatient care.

Thus, acute tubular necrosis is the leading cause of AKI among hospitalized patients due to the variety of factors leading to renal tubular injury in the acute hospital environment.