Three Cases of Congenital Smooth Muscle Hamartomas

ABSTRACT

Congenital smooth muscle hamartomas (CSMHs) usually appear at birth as skin-colored or slightly hyperpigmented patches or plaques on the trunk or extremities and are often covered by and increased amount of vellus hair. Histopathologically, it represents a proliferation of smooth muscle bundles within the dermis(1,2). We herein report on three cases of localized CSMHs; Case 1 was a 2-month-old boy who presented with a skin-colored, 6x5cm-sized plaque with folds, hypertrichosis and pseudo- Darier's sign on the face, an unusual site. But there was no hyperpigmentation. Case 2 and 3 were both 1-month-old boys who presented with typical hyperpigmented, hairy plaques on the lateral aspect of the left thigh.