Porokeratoses-A Rare Group of Dermatoses

Abstract

Porokeratoses represent a rare group of skin diseases characterized by abnormal keratinization. The condition may have a genetic background and can be triggered by environmental factors, including UV exposure and infections. Several clinical variants of porokeratosis can be distinguished, including Mibelli's porokeratosis, disseminated superficial actinic porokeratosis, superficial disseminated porokeratosis, and porokeratosis palmaris plantaris et disseminata. Diagnosis is established based on clinical and histopathological examination, dermatoscopy, and reflectance confocal microscopy. Various treatment options are available, including topical combination therapy with cholesterol and statins, topical retinoids, cryotherapy, laser therapy, and surgical excision of lesions, but none are fully effective. The success of these treatments can vary significantly based on the specific type of porokeratosis and individual patient characteristics, with many outcomes falling short of expectations. Since the disease is considered a precancerous condition, patients with porokeratosis should remain under regular dermatological control.

Keywords: abnormal keratinization; malignant transformation; porokeratoses.

Figure 1

Histopathological features of disseminated superficial actinic porokeratosis (DSAP) include the presence of a cornoid lamella, epidermal atrophy, and lymphocytic infiltration in the dermis. The mevalonate pathway, responsible for cholesterol biosynthesis, is linked to the pathogenesis of porokeratosis.

Figure 2

(A) Disseminated superficial actinic porokeratosis (DSAP): diffuse, small plaques on the man’s forearm. (B) Dermatoscopic view—a peripheral white line with a doubled edge, characteristic of porokeratosis (black arrow).

Figure 3

(A) Porokeratosis of Mibelli—two plaques on the man’s arm and forearm. (B)Dermatoscopic view: characteristic peripheral white-yellow line with a doubled edge (black arrow) and multiple dot-type vessels.

Figure 4

(A) Disseminated superficial porokeratosis—multiple small erythematous plaques on the woman’s back. (B) Dermatoscopic view—a peripheral, interspersed white line with a doubled edge and centrally located linear vessels and single keratotic plug at the openings of hair follicles (black arrow).

Figure 5

(A–C) Porokeratosis palmaris, plantaris et disseminata: multiple small plaques on the woman’s hands and feet. (B–D) Dermatoscopic view—peripheral white lines with a doubled edge (black arrow) with a central structureless area, characteristic of porokeratosis.