Which of the following is a pre-renal cause of acute kidney injury (AKI)?

Volume depletion is identified as a pre-renal cause of acute kidney injury (AKI) because it involves a reduction in blood flow to the kidneys due to a decrease in blood volume. This can occur from conditions such as dehydration, significant blood loss, or fluid loss from vomiting or diarrhea. When the kidneys receive insufficient blood flow, they can become unable to effectively filter waste products from the blood, leading to impaired kidney function.

In cases of volume depletion, the underlying issue is related to the supply of blood rather than a problem within the kidneys themselves. Addressing the underlying cause of the volume depletion often leads to an improvement in kidney function, making it a reversible form of AKI.

Other options like acute glomerulonephritis represent intrinsic renal causes, where the injury occurs directly within the kidney tissue. Septic shock can lead to AKI primarily through its effects on blood flow and perfusion, but it typically results in multi-organ dysfunction rather than being classified purely as pre-renal. Rhabdomyolysis is another intrinsic cause of AKI due to muscle damage that releases myoglobin, which is harmful to the kidneys. These distinctions are essential when diagnosing the etiology of AKI and managing patient care.