1st April 2022

A 36-year-old man presents to A&E with severe back pain, and a numb left leg

A 36-year-old man presents to A&E with severe back pain, and a numb left leg. On examination, he has a loss of perianal sensation. He complains that he cannot pass urine, and a bladder scan shows 550ml in his bladder. The patient has a past medical history of HIV and is not known to services, having self-discharged. An MRI spine demonstrates compression at the L3-S1 level.

What is the most likely aetiology underlying this diagnosis?

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