Disseminated Superficial Actinic Porokeratosis (DSAP): A Case Report Highlighting the Clinical, Dermatoscopic, and Pathology Features of the Condition

Abstract

Porokeratosis describes a heterogenic group of keratinization disorders in which lesions are papules and plaques that demonstrate central atrophy surrounded by a hyperkeratotic margin. Clinical variants include not only porokeratosis of Mibelli, but also disseminated superficial, disseminated actinic superficial, linear, punctate, and palmaris et plantaris disseminata. Porokeratosis has a risk of malignant transformation. A woman with disseminated superficial actinic porokeratosis (DSAP) whose lesions presented as pruritic plaques and papules is described. The diagnosis was suspected clinically, supported by dermoscopy findings, and confirmed histologically. The condition-associated pruritus was managed symptomatically; her skin lesions will be monitored clinically. Clinical manifestations, dermatoscopic features, pathology findings, and treatment options for DSAP are summarized.

A Case of Disseminated Superficial Actinic Porokeratosis Successfully Treated With Topical Lovastatin/Cholesterol Gel

“…Primary care physicians should be aware that DSAP may mimic actinic keratosis, seborrheic keratosis, psoriasis, lichen planus, and more [ 12 , 13 ]. DSAP lesions may carry a small risk of malignant transformation, up to 6.9%-11.6%, with squamous cell carcinoma being the most common, followed by basal cell carcinoma and melanoma [ 14 ]. Some studies suggest that DSAP may have a higher risk of malignant transformation compared to other porokeratosis variants; therefore, accurate and timely identification of DSAP lesions with appropriate treatment is crucial in preventing future morbidity and mortality [ 15 ].…”

Porokeratoses—A Comprehensive Review on the Genetics and Metabolomics, Imaging Methods and Management of Common Clinical Variants

“…Clinical Presentation DSAP, initially described by Chernosky and Freeman in 1967 [16], usually presents as multiple pink or brown annular atrophic/keratotic macules and papules, usually with a diameter of <1 cm, located particularly on sun-exposed areas, including the extensor surface of the arms and lower extremities (Figure 1) [1,13,17,18]. In about 15% of cases, the lesions appear on the face [19]. Small papules of DSAP slowly progress into keratotic plaques characterised by a keratotic rim, which might be enhanced using exogenous pigmenting agents, such as povidone-iodine [20], fake tan lotion [21], gentian violet [22,23] but also permanent marker or ink.…”

“…Small papules of DSAP slowly progress into keratotic plaques characterised by a keratotic rim, which might be enhanced using exogenous pigmenting agents, such as povidone-iodine [20], fake tan lotion [21], gentian violet [22,23] but also permanent marker or ink. Skin lesions in sporadic form usually develop in the third and fifth decade of life [1,18,24], but familial DSAP usually manifests at a younger age (3rd-4th decade) [19,24]. Female predominance has been reported [25].…”

“…Loss or thinning of the granular layer, the presence of basal and/or spinous keratinocyte vacuolisation and sometimes atypia beneath the cornoid lamella, focal dyskeratosis in the spinous layer, diffuse epidermal atrophy and spongiosis are among the characteristic pathology features in DSAP [1,71]. Solar elastosis and dilated papillary vessels accompanied by superficial band-like lymphocytic inflammatory infiltrate (lichenoid/interface dermatitis pattern) in the central aspect of the lesion may be present in some instances [1,19,74]. The latter should be differentiated from lichen planus-like keratosis (benign lichenoid keratosis), which never features cornoid lamellae [1,82].…”