Which of the following is not a sign or symptom of acute kidney injury (AKI)?

Acute kidney injury (AKI) is characterized by a rapid decline in renal function, leading to various signs and symptoms. Among the options listed, severe headaches are not typically associated with AKI. The primary indicators of this condition revolve around the body's inability to adequately filter waste and fluid, which can lead to specific clinical manifestations.

Shortness of breath can occur in AKI due to fluid overload when the kidneys are unable to excrete excess fluids, leading to pulmonary edema. Increased levels of blood urea nitrogen (BUN) and creatinine are classic markers of impaired kidney function, reflecting the kidneys' reduced ability to filter and excrete metabolic waste. Hyperkalemia, or elevated potassium levels, often arises in AKI due to the kidneys' reduced ability to excrete potassium, resulting in potential cardiac complications.

In contrast, severe headaches do not directly indicate renal impairment or fluid imbalance typically seen in AKI. While they could arise from other underlying issues, they are not characteristic of AKI itself. This distinction is crucial for recognizing the signs and symptoms specific to different medical conditions.