2nd August 2023

A 46 year old man is referred to the general medical outpatients clinic for worsening leg swelling, refractory to high doses of furosemide.

A 46 year old man is referred to the general medical outpatients clinic for worsening leg swelling, refractory to high doses of furosemide. He recently returned from the Democratic Republic of Congo after living there for 6 months. He has never been investigated for heart failure and has no known past medical history or family history.

On examination, heart sounds are normal, JVP is not raised, and bilateral non-pitting oedema extends to the mid-thigh. There is also evidence of scrotal swelling. His calves are soft and not tender. Observations are within normal range, and bloods, including BNP and thyroid function tests, are normal, except for a raised eosinophil count. The echocardiogram shows normal ventricular function.

What is the most likely cause?

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