A 20-year-old man, denied of any symptom and family history except progressive enlargement of his hands and feet. Physical examination revealed deepening of forehead lines, clubbing fingers and enlargement of hands/feet. Blood test showed high human growth hormone (8.81 ng/Ml; normal, 0-3 ng/Ml). Radiographic examination showed cortical thickening and shaft widening of proximal and middle phalangeal bone of all digits as well as metatarsal bones of both feet. Tc-99m MDP bone scintigraphy showed prominent tracer uptake along the appendicular skeleton, especially the tibiae and femora. Clinical and imaging fmdings suggest the diagnosis of pachydermoperiostosis.