15th July 2024

A 73-year-old woman presented to the medical assessment unit with an acute kidney injury on a background

A 73-year-old woman presented to the medical assessment unit with an acute kidney injury on a background of 1 day of lower abdominal pain and watery, blood-stained diarrhoea.  She had a past medical history of type 2 diabetes, hypertension and ischaemic heart disease. She has a smoking history of 30 pack years. Last month, she was diagnosed with atrial fibrillation and was commenced on Apixaban.  On examination, she had an irregularly irregular pulse with a rate of approximately 110 bpm, blood pressure was 178/83 and she was afebrile. Some general lower abdominal tenderness to palpation was noted but no masses were felt.  The doctor was unable to palpable the dorsalis pedis and posterior tibial pulses bilaterally. Urinalysis showed blood ++ and protein ++.  Investigations were as follows:

What is the most likely cause of her acute kidney injury?

Select the SINGLE most appropriate option from the list below. Select ONE option only.