13th February 2025

A 30-year-old male presents with muscle weakness, restriction of eye movements and pigmented peripheral changes in the retina.

A 30-year-old male presents with muscle weakness, restriction of eye movements and pigmented peripheral changes in the retina. There is also a strong family history of nyctalopia. A trichrome stained muscle biopsy reveals “ragged red fibres”. What other investigations should you do?

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