An 8-month-old boy presented with multiple facial lesions present for the last 2 months, beginning as a cluster of small papules on the right cheek. Examination revealed multiple, 3-6 mm, erythematous, discrete as well as confluent, firm papules distributed symmetrically over the cheeks, chin, forehead, and eyelids (Fig. 1). Routine hematological and biochemical tests, including lipid profile were normal. Histopathology of a papule showed a well-circumscribed collection of histiocytes in the upper and mid-dermis. The cells were S100 and CD1a negative but factor XIIIa positive. A diagnosis of benign cephalic histiocytosis was made and the child was kept under periodic follow-up.

Fig. 1 Erythematous papules of benign cephalic histiocytosis.

Benign cephalic histiocytosis is a rare, self-limiting non-Langerhans cell histiocytic proliferative disorder of young children, primarily affecting the face. The average age of onset is 15 months. Asymptomatic erythematous macules and papules on the face gradually become reddish-brown and may spread to the neck, trunk, and upper limbs; mucous membranes are not involved. The differentials include Langerhans cell histiocytosis (red-brown papules that show erosion, hemorrhage and crusting), juvenile xanthogranuloma (orange/yellow papules often with mucosal/ocular involvement), urticaria pigmentosa (yellowish papules turning into weals on firm stroking), and generalized eruptive histiocytoma (recurrent crops of hundreds of yellowish/red-brown papules on face, trunk, and extensors). The eruption clears spontaneously after a variable period of time and requires no treatment.