Linear porokeratosis Q82.8

Author: Prof. Dr. med. Peter Altmeyer

All authors of this article

Last updated on: 01.03.2022

Dieser Artikel auf Deutsch

Synonym(s)

congenital unilateral linear porokeratosis; linear unilateral porokeratosis; neviform porokeratosis; porokeratosis mibelli zosteriformis; porokeratosis zosteriformis

Definition
This section has been translated automatically.

Rare, congenital or acquired variant of porokeratosis, with typical anular horn papules in linear or zosteriform arrangement (arrangement in the Blaschko lines).

Etiopathogenesis
This section has been translated automatically.

A cutaneous mosaicism (cutaneous mosaic) is assumed etiopathogenetically.

Type I: early somatic mutation in the keratinocytes.

Type II: present germline mutation. In addition, somatic mutations occur which lead to the loss of heterozygosity in the area concerned.

Manifestation
This section has been translated automatically.

Congenital or early childhood.

Clinical features
This section has been translated automatically.

Cutaneous mosaic dermatosis with linear, band-shaped, also circular or garland-shaped, or half-sided, (cases affecting an entire half of the body have been described), red or red-brown, sharply demarcated, keratotic papules and plaques. No significant subjective complaints. Apart from the very characteristic macro-pattern, the histological picture is diagnosis-defining.

2 variants can be distinguished clinically:

  • Type I: exclusively unilateral linear or band-shaped affection.
  • type II: generalized porokeratosis with additional blaschcoid structures (linear or swirled groupings)

Histology
This section has been translated automatically.

Hyperkeratotic epidermal papules with parakeratotic horny lamella. Acanthosis, hyperkeratosis, flag-like parakeratosis (cornoid lamella). At the base of the parakeratosis, keratinocytes with pyknotic atypias and perinuclear edema appear.

Differential diagnosis
This section has been translated automatically.

ILVEN: Typical aspect of anular horn papules missing. Differential histology.

Lichen planus: Porokeratosis does not itch; the lichenoid aspect of the lichen planus is missing. Differential histology.

Porokeratotic eccrineostiumnaevus (Porokeratotic eccrine ostial and dermal duct nevus - PEODDN). Also in this case a cornoid lamella is formed, but over dilated eccrine sweat gland ducts.

Porokeratotic eccrine duct and hair follicle nevus (PEHFN). Formation of a cornoid lamella over dilated follicle ostia.

Therapy
This section has been translated automatically.

Education of patients about a possible lifelong existence of the disease, furthermore about an increased risk of carcinoma within the lesional skin. Careful light protection necessary.

External therapy
This section has been translated automatically.

Application of mild keratolytics, e.g. low doses of vitamin A acid R256.

Operative therapie
This section has been translated automatically.

If necessary, cryosurgery, excision orCO2 or erbium-Yag laser.

Progression/forecast
This section has been translated automatically.

Chronic course. Spontaneous healings are possible. Malignant degeneration not excluded.

Literature
This section has been translated automatically.

  1. Apel HP et al (1986) Porokeratosis linearis unilateralis (Linear porokeratosis). Dermatologist 37: 284-286
  2. Boente Md Mdel C et al (2003) Linear porokeratosis Associated with Disseminated Superficial Actinic Porokeratosis: A New Example of Type II Segmental Involvement. Pediatr Dermatol 20: 514-518
  3. Curnow P et al (2003) Multiple squamous cell carcinomas complicating linear porokeratosis. Australas J Dermatol 44: 136-139.
  4. Nazarian RS et al (2020) Linear porokeratosis presenting in adulthood: A diagnostic challenge: A case report. SAGE Open Med Case Rep 8:2050313X20919613.
  5. Sertzing P et al (2010) Congenital linear unilateral porokeratosis. JDDG 8:943-944
  6. Tseng SS et al (2002) Linear porokeratosis with underlying bony abnormalities. Cutis 69: 309-312

Disclaimer

Please ask your physician for a reliable diagnosis. This website is only meant as a reference.

Authors

Last updated on: 01.03.2022