26th August 2024

A 25-year-old man is referred to a general medical clinic with fatigue. He reports no other symptoms

A 25-year-old man is referred to a general medical clinic with fatigue. He reports no other symptoms. He has always found exercise challenging and finds he becomes breathless on mild exertion. If going uphill, he often has to stop a short way up and catch his breath, but then often gets a boost of energy and can get to the top in one go. He has no other past medical history. He lives in a shared house with friends and has not travelled outside of the UK in the last two years. He smokes 20 cigarettes a day and drinks approximately 15 units of alcohol per week. He works as an estate agent.

His blood test results are below:

Hb 145 [140 – 180]

MCV 85 [80 – 98]

WCC 8.9 [4.0 – 10.0]

Plts 356 [150 – 400]

ALT 103 [10 – 40]

AST 166 [10 – 40]

ALP 87 [35 – 104]

Albumin 47 [35 – 55]

Bilirubin 8 [5 -21]

GGT 28 [6 – 42]

CK 12,067 [20 – 200]

Na 144 [135 – 145]

K 3.9 [3.5 – 5]

Urea 4.2 [3.4 – 6.7]

Creatinine 75 [60 – 115]

Calcium 2.45 [2.20 – 2.60]

Which of the following is most likely to account for his symptoms?

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