Tim is a 63-year-old retired café owner who presents with a 12-month history of progressive fingernail discolouration. 

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<p>Tim is a 63-year-old retired café owner who presents with a 12-month history of progressive fingernail discoloration.</p><p>He has had difficult-to-manage hypertension and diabetes for 10 years and was diagnosed with chronic renal failure three years previously.</p><p>For the past year, he has been receiving regular haemodialysis for end-stage renal disease.</p><p>On examination, his fingernails show white proximal nail beds with no lunula and a distal pink transverse arcuate band. The toenails are unaffected.</p><p>Fungal examination of the nail clippings is negative.</p>

Dr Kate Kelso is a GP and medical editor at Australian Doctor.