Congenital miliaria crystallina.

Miliaria crystallina is a transient, superficial obstruction of eccrine sweat ducts resulting in rapidly evolving noninflammatory vesicles. The disease is observed frequently in hot, humid, tropical climates and in the neonatal period, but congenital occurrence is very rare. Miliaria crystallina must be considered in the differential diagnosis of bullous diseases in newborns.