Genodermatoses - PPK Flashcards
List 3 types of diffuse PPK
WITHOUT ASSOC. FEATURES
- Unna-Thost
- Vorner
WITH ICHTHYOSIS
- Bothnia
- Kimonis
- Nagashima
- Mal de Maleda
FEATURES OF UNNA-THOST
Palmoplantar skin is initially red, followed by the appearance of thick, yellow hyperkeratosis by 3-4 years of age
- in adults, see confluent hyperkeratosis with smooth, waxy surface and sharply demarcated erythematous border sparing dorsal aspects of palms and soles
Difference between Unna Thost and Vorner
Vorner has epidermolytic hyperkeratosis
Vorner also has a waxy red border
Genes affected in unna thost and Vorner
K1 and K10
Bothnia syndrome
Diffuse PPK without associated features (isolated, non syndromic) - autosomal dominant, due to AQP5, leading to incr keratinocyte water uptake rather than transepidermal water loss
- White spongy appearance on exposure to water
Mel de Maleda
SLURP1 MUTATIONS
- Progressie trans gradient hyperkeratosis in early infancy then severe, impairing mobility of hands and resulting in hyperhidrosis, odour and fissures
- elbows/knees/wrists/ankles can be involved
Loricrin keratoderma
Mutations in Loricrin, which encodes a glycine rich cornfield envelope protein
- may have generalised desquamation of features of collodion baby can be present at birth with evolution to a mild generalised ichthyosis
- NO deafness , but presence of ichthyosis distinguish Loricrin from Vohwinkel syndrome
Vohwinkel syndrome inheritance and features
Diffuse PPK with associated features
- AUTOSOMAL DOMINANT
- GJB2
(Same gene implicated in KID syndrome and Bart-Pumphrey)
- FEATURES:
- pseudo-ainhum
- autoamputation
- pitted and stippled honeycomb like diffuse PPK
- stellate starfish keratoses on knuckles
- high pitches sensorineural deafness
KLICK syndrome
Keratosis linearis ichthyosis congenita sclerosing keratoderma
- mild congenital ichthyosis and diffuse trans gradient PPK
- digital constriction bands
- flexion deformity of fingers with sclerosis and parallel linear arrays of keratotic papules in flexural areas of extremities
- development of SCC has been reported
PPK with malignant potential
KLICK - SCC has been reported
Huriez - SCC in areas of atrophic skin , risk >100 fold
Howel - Evans - oesophageal cancer
Olmsted - SCC and melanoma reported
Huriez syndrome
Diffuse PPK
Autosomal dominant
Onset during infancy with diffuse scleroatrophy of hands
Eventual sclerodactyly with absent dermatoglyphs
SCC in areas of atrophic skin , risk >100 fold
CLOUSTON SYNDROME
GJB6
AUTOSOMAL DOMINANT
Hypotrichosis, diffuse PPK, nail dystrophy
— hypotrichosis eventuates to complete alopecia
Pebbled appearance on dorsal digits, knees and elbows
Shopf-Schulz-Passarge
Mutations in WNT10A role in development of ectodermal appendages
- combination of diffuse PPK, facial telangiectasias, reticulate erythema, dental anomalies (hypodontia & small teeth), nail dystrophy and hypotrichosis
- hydrocystoma s, tumours of follicular infundibulum
Olmsted syndrome
DIFFUSE PPK
- autosomal dominant and less common AR Variants due to different gain of function mutations in TRPV3
- X linked recessive variant has total alopecia and severe nail dystrophy
- see sharply defined PPK with erythematous border
- erythema and warty hyperkeratosis develop in perioral and perianal regions
- erythromelalgia , deafness and joint laxity, periodontal disease
- nail dystrophy
—> recurrent infections, SCC and melanoma also reported
Papillon LeFevre and Haim Munk syndromes
Diffuse PPKs
- autosomal recessive
- periodontitis, diffuse trans gradient PPK with associated erythema, pseudoainhum
- acral melanomas have been reported
