Progressive cribriform and zosteriform hyperpigmentation.

Five cases of progressive cribriform and zosteriform hyperpigmentation are described. The following criteria were fulfilled: (1) uniformly tan cribriform macular pigmentation in a zosteriform distribution; (2) a histologic pattern that consisted of a mild increase in melanin pigment in the basal cell layer and complete absence of nevus cells; (3) no history of rash, injury, or inflammation to suggest postinflammatory hyperpigmentation; (4) onset well after birth with gradual extension; and (5) lack of other associated cutaneous or internal abnormalities. This appears to be a newly described entity, although it resembles a Becker's nevus without hypertrichosis or an typical café au lait spot. We believe that such progressive cribriform and zosteriform pigmentation is not uncommon.