USMLE Q Bank Step 1- 215- Pharmacology Question

A 28 year old woman visits her physician for evaluation of bilateral proximal muscle weakness and muscle pain. Her symptoms started last week and her pain is getting worse. Her records indicate alcohol abuse and cocaine addiction. She is HIV positive and she takes zidovudine. She also takes simvastatin for hypercholesterolemia. A muscle biopsy shows significant changes in mitochondrial histology.

What is the most likely etiology of this patient’s condition

A-Alcohol abuse

B-Cocaine addiction



E-HIV infection


Zidovudine causes significant changes in mitochondrial histology with depletion of mitochondrial DNA.

Zidovudine is the only choice associated with mitochondrial changes. All of other choices cause myositis and muscle pain but the only one which causes mitochondrial changes is zidovudine.

The correct answer is C

11 thoughts on “USMLE Q Bank Step 1- 215- Pharmacology Question”

  1. It’s it possible to include medicinal chemistry coz I think it helps answer some of these questions

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