This patient presented with discoloration of his palms and soles. He reported a normal diet and had normal serum creatinine, thyroxine, and bilirubin concentrations. What is the diagnosis?
- hyperlipidemia or
- Diabetes mellitus or
- syphilis


Diabetes mellitus.

Yellow discoloration of the skin may be associated with carotenemia, hypothyroidism, diabetes mellitus, liver disease, and renal disease.