Widespread porokeratotic eccrine ostial and dermal duct nevus along Blaschko lines

Porokeratotic eccrine ostial and dermal duct nevus is a congenital hamartoma of possible eccrine origin with no malignant potential. It is usually localized at the extremity of a single limb, while wider systematized distribution has rarely been documented. A child with an unusually widespread nevus following Blaschko lines is reported. The disorder had a striking presentation in the form of a systematized linear epidermal nevus composed of multiple tiny filiform keratotic spines, which histologically corresponded to columns of porokeratosis. Serial histopathologic sections of a 4-mm punch biopsy specimen barely demonstrated an anatomic relationship between the porokeratotic columns and the underlying acrosyringeal duct. This report provides further evidence of porokeratotic eccrine ostial and dermal duct nevus being distributed along Blaschko lines, thus confirming it is a peculiar epidermal nevus due to a mosaic cutaneous condition.

Congenital facial linear porokeratosis

We report a unique case of congenital linear porokeratosis with exclusive facial involvement in a 27-year-old Chinese man. No other family member was affected. To our knowledge, this is the first report in the English literature of congenital linear porokeratosis confined to the face.

Coexistence of disseminated superficial porokeratosis in childhood with congenital linear porokeratosis

Porokeratosis is a genodermatosis characterized by abnormal epidermal keratinization with the histologic finding of cornoid lamella. To date, five clinical variants have been identified. However, the coexistence of these variants in a single patient has been described only rarely. We report a 5-year-old girl with the simultaneous occurrence of porokeratotic lesions in linear and disseminated patterns. Linear lesions were detected at birth and the disseminated lesions developed at the age of 3 years. Histologically the lesions had cornoid lamella, which is typical of this condition.

Linear porokeratosis presenting as erosions in the newborn period

The classic appearance of porokeratosis is characterized by a hyperkeratotic annular rim that expands peripherally, leaving an atrophic center. Linear porokeratosis is a variant with collections of such lesions arranged in a linear fashion, usually corresponding to a dermatome or Blaschko's lines. Ulcerations have rarely been reported in patients with porokeratosis. We report an unusual case of linear porokeratosis at birth, with erosions and ulcerations of the face and lower extremity, that eluded diagnosis for nearly a year. Porokeratosis should be considered in the differential diagnosis of erosions in the newborn period.