Langerhans cell congenital histiocytoma

Abstract

A 20-day-old boy was first observed due to a lesion of the left foot present since birth. The child, third son, was born with Cesarean section at 38 weeks, with a weight of 3.500 kg and a length of 50 cm at birth. His parents reported a dark red papule that was covered 3 times by a blackish crust, then fallen, but it had never healed.
The physical examination showed a 4 mm in size, eroded and crusty lesion, just infiltrated on the left plantar region (Fig. 1). The lesion was excised under local anesthesia and the histologic examination (Fig. 2, H&E, 10x and Fig. 3, H&E 100x) showed edema of the superficial dermis, which was crammed with large cells with kidney-shaped nucleus and intensely colored, S-100 and CD1a positive cytoplasm and with a large number of eosinophils, leading to the final diagnosis of congenital Langerhans cell histiocytoma.