Pachyonychia congenita

from Wikipedia, the free encyclopedia
Classification according to ICD-10
Q84.5 Enlarged and hypertrophied nails (congenital) - pachyonychia
ICD-10 online (WHO version 2019)

The Pachyonychia Congenita is a congenital hereditary disease with the Leitkennzeichen thickened finger and toe nails ( onychauxis ) and painful keratome to the palm and the soles of the feet due to a disturbance of keratinization .

The following appear as synonyms :

  • Pachyonychia congenita hereditaria
  • Jadassohn-Lewandowsky syndrome
  • Keratosis congenita multiplex
  • Polykeratosis congenita (Touraine)
  • Pachyonychia ichthyosiformis

Subdivision

On the basis of the underlying mutations , the following sub-forms are currently distinguished:

  • PACHYONYCHIA CONGENITA 1; PC1; PC-K16 with mutations in the KRT16 gene at location 17q21.2
  • PACHYONYCHIA CONGENITA 2; PC2; PC-K17 with mutations in the KRT17 gene at location 17q21.2
  • PACHYONYCHIA CONGENITA 3; PC3; PC-K6a with mutations in the KRT6A gene at location 12q13.13
  • PACHYONYCHIA CONGENITA 4; PC4; PC-K6b with mutations in the KRT6B gene at location 12q13.13
  • PACHYONYCHIA CONGENITA, AUTOSOMAL RECESSIVE possibly separate form

The affected keratins are mainly formed in the skin layers of the palm, the skin appendages such as nails and in the oral mucosa .

distribution

The frequency is unknown; approximately 1,000 patients have been reported worldwide. The inheritance is predominantly autosomal dominant .

Clinical manifestations

Clinical abnormalities for the entire clinical picture are:

  • Nail thickening on all fingers and toes with increased nail curvature already occurring shortly after birth and increasing over time
  • Nail discoloration yellowish-brownish
  • Circumscribed symmetrical hyperkeratosis on the palms and soles of the feet
  • Blistering of the palms when warm
  • Palmoplantar hyperhidrosis (on the palms of the hands)
  • Follicular keratosis of the elbows and knees with dry skin
  • Leukoplakia of the oral mucosa
  • Visible teeth at birth

in adults might be able to dystrophy of the cornea , cataract , reticular pigmentation , hearing loss , Hypotrichose or hoarseness occur.

There are at least three types of nail changes:

  • Normal length nails with hyperkeratosis at the end with a curvature
  • Prematurely ending nail plates with hyperkeratosis distal and exposed fingertip
  • Thin nail plates with hyperkeratosis of varying degrees.

diagnosis

The diagnosis is based on clinical findings and is confirmed by molecular genetic tests .

If the mutation is known, prenatal diagnosis is possible.

Differential diagnosis

The following are to be distinguished:

therapy

A causal treatment is not known, but the symptoms and pain caused by the keratoderma, as well as possible infections, can be treated .

history

The first description was made in 1906 by the German dermatologists Josef Jadassohn and Felix Lewandowsky .

Clinically, it was divided into:

  • Type I with leukoplakia and plantar blistering
  • Type II without leukoplakia, slight keratoses
  • Type III premature tooth development, minor keratoses

An alternative classification is:

  • PC-1 JADASSOHN-LEWANDOWSKY SYNDROME with oral leukokeratosis
  • PC-2 JACKSON-LAWLER TYPE without leukokeratosis of the oral mucosa

as described by AD Jackson and SD Lawler in 1951.

literature

  • J. Löchner, B. Mohr, I. Garcia-Gutierrez, HP Schoppelrey, M. Gummer, R. Breit: [Congenital pachyonychia type II (Jackson-Lawler syndrome)]. In: The dermatologist ; Journal of Dermatology, Venereology, and Allied Fields. Vol. 51, No. 3, March 2000, ISSN  0017-8470 , pp. 192-195, PMID 10789082 .

Individual evidence

  1. ↑ a b c d Pachyonychia congenita. In: Orphanet (Rare Disease Database).
  2. ↑ a b c Bernfried Leiber (founder): The clinical syndromes. Syndromes, sequences and symptom complexes . Ed .: G. Burg, J. Kunze, D. Pongratz, PG Scheurlen, A. Schinzel, J. Spranger. 7., completely reworked. Edition. tape 2 : symptoms . Urban & Schwarzenberg, Munich et al. 1990, ISBN 3-541-01727-9 .
  3. ↑ a b dermis
  4. ↑ a b PC1.  In: Online Mendelian Inheritance in Man . (English)
  5. ↑ PC2.  In: Online Mendelian Inheritance in Man . (English)
  6. ↑ PC3.  In: Online Mendelian Inheritance in Man . (English)
  7. ↑ PC4.  In: Online Mendelian Inheritance in Man . (English)
  8. ↑ PACHYONYCHIA CONGENITA, AUTOSOMAL RECESSIVE.  In: Online Mendelian Inheritance in Man . (English)
  9. ↑ J. Jadassohn, F. Lewandowsky: Pachyonychia congenita, Keratosis disseminata circumscripta, tylomata, leucokeratosis linguae. In: Jacobs Ikonographia Dermatologica. Berlin Urban and Schwarzenberg Verlag, Vol. 1, 1906, p. 29.
  10. ^ AD Jackson, SD Lawler: Pachyonychia congenita; a report of six cases in one family, with a note on linkage data. In: Annals of eugenics. Vol. 16, No. 2, September 1951, pp. 142-146, PMID 14885876 .

Web links