The most common cause of prerenal acute kidney injury (AKI) is:

Choice A reason: Loss of short-term memory is a hallmark of Alzheimer’s disease, as seen in the patient’s difficulty recalling recent events. This reflects early hippocampal damage, impairing new memory formation, making it a correct clinical manifestation for this diagnosis.

Choice B reason: Alzheimer’s disease is the most likely diagnosis, given progressive memory loss, word-finding difficulties, and an MMSE score of 20/30 in a 65-year-old. These symptoms align with Alzheimer’s neurodegenerative pattern, making this the correct diagnosis.

Choice C reason: Vascular dementia typically presents with stepwise cognitive decline and focal neurological signs, often with vascular risk factors. The patient’s gradual memory loss without such history better fits Alzheimer’s, making vascular dementia incorrect.

Choice D reason: Word-finding difficulties, as exhibited, are a hallmark of Alzheimer’s, reflecting language cortex involvement. This progressive aphasia, common in early stages, impairs communication, making it a correct clinical manifestation for this patient.

Choice E reason: Disorientation to time and place, though not explicitly stated, is a hallmark of Alzheimer’s, often emerging as memory declines. Given the patient’s MMSE score and symptoms, this is likely, making it a correct manifestation.

Choice A reason: Vasodilation increases blood flow, causing redness and heat, but doesn’t directly cause fluid leakage. Increased capillary permeability allows fluid to escape into tissues, causing edema, so this is incorrect for the primary cause of inflammatory edema.

Choice B reason: Increased capillary permeability, triggered by inflammatory mediators, allows plasma to leak into tissues, causing edema. This is the primary mechanism during inflammation, making it the correct choice for the cause of edema in the process.

Choice C reason: Neutrophil emigration fights infection but doesn’t directly cause fluid accumulation. Capillary permeability changes lead to edema, so this is incorrect for the cause of swelling in inflammation.

Choice D reason: Endothelial cell contraction contributes to permeability but is a secondary mechanism. Increased capillary permeability is the overarching process causing fluid leakage and edema, so this is less precise and incorrect.