Linear porokeratosis of the foot with dermoscopic manifestations: A case report

BACKGROUND Porokeratosis(PK)is a common autosomal dominant chronic progressive dyskeratosis with various clinical manifestations.Based on clinical manifestations,porokeratosis can be classified as porokeratosis of mibelli,disseminated superficial porokeratosis,disseminated superficial actinic porokeratosis,linear porokeratosis(LP),porokeratosis palmaris et plantaris disseminata,porokeratosis punctata,popular PK,hyperkeratosis PK,inflammatory PK,verrucous PK,and mixed types.We report a case of LP in a child and describe its dermoscopic findings.CASE SUMMARY Linear porokeratosis is a rare PK.The patient presented with unilateral keratinizing maculopapular rash of the foot in childhood.The patient underwent skin pathology and dermoscopy,and was treated with liquid nitrogen freezing and topical drugs.CONCLUSION From this case we take-away that LP is a rare disease,by the dermoscopic we can identify it.

Mixed porokeratosis with a novel mevalonate kinase gene mutation:A case report

BACKGROUND Porokeratosis is a rare,acquired,or inherited disorder of keratinization.There are numerous clinical types of porokeratosis and they can coexist in one patient and multiple members of an affected family.However,coexistence of disseminated superficial actinic porokeratosis(DSAP)and porokeratosis ptychotropica(Ppt)is rare.CASE SUMMARY A 45-year-old man presented with long-standing skin lesions.Physical examination identified numerous small,brown 2-mm to 4-mm patches on his face and several hyperkeratotic,verrucous plaques on his trunk and extremities.His father and one of his brothers also had similar lesions for years.Skin biopsies indicated a cornoid lamella in the epidermis.We identified c.155G>A mutation in the mevalonate kinase(MVK)gene,which converted a serine residue to asparagine(p.Ser52Asn)and was causative for porokeratosis in this family.A clinicopathologic diagnosis of DSAP and Ppt with a novel MVK gene mutation was made.The hyperkeratotic plaques on the patient’s scrotum were completely removed more than 10 times using a microwave knife.CONCLUSION An unusual case of DSAP coexisting with Ppt harbored a novel MVK gene mutation also present in the patient’s family.

Dermoscopic Features and Gene Mutation in the Mevalonate Pathway of Five Sporadic Patients with Porokeratosis

Porokeratosis （PK）,first described in 1983,is a chronic parakeratotic skin disorder.Clinical types include porokeratosis of Mibelli （PM）,disseminated superficial PK,disseminated superficial actinic porokeratosis （DSAP）,facial PK,and ptychotropica porokeratosis （PP）.Dermoscopic images of PK show an obvious annular margin with scales and an atrophied center.[1] Wood＇s lamp pictures of PK present a diamond necklace-like structure.[2]Gene mutations in mevalonate pathway enzymes,such as mevalonate kinase （MVK）,phosphomevalonate kinase （PMVK）,mevalonate decarboxylase （MVD）,and famesyl diphosphate synthase （FDPS）,may be involved in the pathogenesis of PK.[3,4] In the present study,five sporadic patients with PK were recruited.Dermoscopic features were investigated,and genetic testing was conducted.

A Case Report of Inflammatory Disseminated Superficial Porokeratosis: An Eruptive Pruritic Papular Variant of Porokeratosis

Introduction: Eruptive pruritic papular porokeratosis (EPPP) is a rare variant of porokeratosis. Several cases of this varient of porokeratosis had been reported.Here, we reported an old man with this rare kind of porokeratosis which is often eruptive and pruritic.Case report: A 72 years-old Chinese man presented to our hospital with intensively pruritic papular lesions on his trunk and limbs. Physical examination showed numerous scattered keratotic papules measuring 35 mm in diameter on his trunk and extremities. Some coalesced into anannular lesion with a slightly raised peripheral red rim. A tissue biopsy revealed the presence of a cornoid lamella. The patient was diagnosed with EPPP. After 3-months’ treatment of antihistamines and topical steroid agents, the lesions and the pruritus were diminished.Discussion: EPPP predominantly happens in an old male demographic. Patients with EPPP often develop pruritic papules spread on the body with or without preexisting typical porokeratosis lesions, and the lesions can subside within few months, leaving small brown spots or annular lesions. EPPP has the unique histological characteristic of porokeratosis cornoid lamella. The mechanism of EPPP is still unknown. It is important for clinicians to be aware of a disseminated pruritic papules as a manifestation of EPPP.Conclusion: The lesion of porokeratosis can be manifested as eruptive papules with intensive itch. When a patient develops eruptive pruritic papules, it is necessary to consider the possibility of EPPP. Histopathology is necessary for diagnosis.

Twists and turns of the genetic story of mevalonate kinase-associated diseases:A review

Mevalonate kinase (MK)-associated diseases encompass a broad spectrum of rare auto-inflammatory conditions, all resulting from pathogenic variants in the mevalonate kinase gene (MVK). Their clinical manifestations are highly variable, ranging from more or less serious systemic disorders, such as hereditary recurrent fevers, to purely localized pathologies such as porokeratosis. The oldest condition identified as linked to this gene is a metabolic disease called mevalonic aciduria, and the most recent is disseminated superficial actinic porokeratosis, a disease limited to the skin. The modes of inheritance of MK-associated diseases also diverge among the different subtypes: recessive for the systemic subtypes and dominant with a post-zygotic somatic genetic alteration for MVK-associated porokeratosis. This review quickly retraces the historical steps that led to the description of the various MK-associated disease phenotypes and to a better understanding of their pathophysiology, then summarizes and compares the different genetic mechanisms involved in this group of disorders, and finally discusses the diverse causes that could underlie this phenotypic heterogeneity.