A 5-year-old girl presented with sudden onset, numerous, mildly itchy, non-scaly elevated lesions on face, legs and arms (Fig. 1-3) for a duration of 3-4 days, preceded by an episode of fever and cough. There was no family history or intake of drug. Examination, revealed numerous dome-shaped and flat-topped red-brown papules and papulo-vesicles involving face, extensor aspects of both arms and lower legs. Some of the vesicles spontaneously ruptured while some ruptured in response to itching. Trunk, palm, soles and mucosa were spared. A diagnosis of Gianotti-Crosti syndrome was made.

Fig. 1 Papules and papulovesicles over face.

Fig. 2 Papules and papulovesicles involving arm.

Fig. 3 Symmetrical distribution of papulovesicles on lower extremities.

Gianotti-Crosti syndrome or papuloacrodermatitis of childhood is a common, self-limiting dermatosis which affects children between 6 mo-12 y of age with no sexual predilection and is more common in early summer. Exact pathogenesis is not known. It is associated with viral and bacterial infections and some vaccines. Viral causes include Hepatitis B virus, Epstein barr virus (EBV), respiratory syncytial virus, enterovirus etc. with EBV being the most common cause. Mycoplasma pneumoniae and Group A beta hemolytic streptococci are the bacterial causes. It can also occur following DPT, BCG or HepB vaccination. It is usually preceded by a prodrome of fever and upper respiratory tract symptoms. The disease is self-limiting and the lesions usually resolve in 3-4 weeks without any sequelae. The close differentials include scabies, papular urticaria and prurigo simplex; none of which is preceded by a prodrome. In scabies, nocturnal itching and a positive family history is noticeable. Papular urticaria and prurigo simplex are entities characterized by chronic course with relapses and remissions.