Carlos is a 24-year-old tradesman who presents with one week of sudden-onset papules on the back and extremities that are itchy, painless and yellowish. 

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<p>Carlos is a 24-year-old tradesman who presents with one week of sudden-onset papules on the back and extremities that are itchy, painless and yellowish.</p><p>Carlos usually avoids doctors. He is typically very healthy, with no significant past medical history.</p><p>He drinks alcohol on weekends (maximum four standard drinks a day) and does not use any recreational drugs.</p><p>He admits his diet is not great, and he tends to eat fast food on job sites.</p><p>His father and two paternal uncles have diabetes, hypercholesterolaemia and CVD, with onset in their 40s.</p><p>On examination, his BMI is 25kg/m2, and there are multiple non-tender papules that appear yellow and firm over the trunk, back and extremities, accentuated on the extensor surfaces (pictured).</p>

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