Congenital infiltrating lipoma of the upper limb in a patient with von Willebrand disease

Infiltrating lipoma is a rare variety of lipoma, characterized by an infilt ration of the adipose tissue of the muscles. Infiltrating lipomas are usual ly classified in two groups: intermuscular infiltrating lipoma and intramus cular infiltrating lipoma. Most are acquired, and they usually appear in mi ddle-aged individuals. Exceptionally, they are congenital. In such cases th ey are not related to other diseases. We report an 8-year-old boy with a co ngenital infiltrating lipoma of the upper limb and von Willebrand disease. Both diseases are linked to an alteration in chromosome 12, but this clinic al association seems to be random rather than causal.