Question category: Nephrology
An 18 year old male presents with features of infectious mononucleosis. However he has now noticed quite marked swelling in his face and legs. Bloods reveal a low albumin. Urinalysis reveals proteinuria and 24 hour collection reveal an protein excretion of 4g/day. There is nil of note on a renal biopsy. What is the most likely underlying cause of his symptoms?