Inherited pigmentary disorders Flashcards
List inherited disorders hypopigmentation
Pigment Wasn’t On High Crazy Charlie Got Half Inside
- piebaldism, Waardenburg (melanocyte migration)
- OCA (melanin synthesis)
- Hermansky pudlak, Chediak Higashi, Cross (melanosome biogenesis)
- Griscelli (melanosome transport)
- Hypomelanosis of Ito (mosaicism)
List inherited disorders of hyperpigmentation
Fathers Insist Lovely Daughters Never Date RanK Fanta Pants w Dark Digits
- Familial progressive hyperpigmentation
- IP
- Linear + whorled naevoid hypermelanoais
- Dowling-Degos / Galli Galli
- Naegelli-Francheschetti-Jadassohn
- Dyskeratosis Congenita
- Reticular acropigmentation of Kitamura
- Fanconi Anaemia
- Peutz Jeghers
- Dyschromatosis (symmetrica hereditaria/ universalis hereditaria)
Piebaldism
- inheritance, features
AD (KIT mutations)
white forlock, midline/ventral depigmentation, areas of hyperpigmentation
Waardenburg
- inheritance
- types + features
AD inheritance PAX 3 MITtens + 10 SOX - PAX3, MITF, SOX10 - type 1 - classic (white forlock, hypopigmentation, heterochromia, dystopia canthorum, deafness, mild MSK) - type 2 - more deaf, less eye changes - type 3 - more MSK - type 4 - hirschsprung
DDx for circumscribed scalp poliosis
Acquired
- vitiligo, drug induced (latanoprost, imiquimod, tyrosine kinase inhibitors), trauma, post-inflammatory, alopecia areata, halo naevus, Vogt-Koyanagi-Harada, Alezzandrini, melanoma-associated leukoderma
Genetic
- Piebaldism, Waardenburg, TS, angora hair naevus, naevus comedonicus
Types of OCA
- inheritance
7 types OCA 1A - complete lack of tyrosinase OCA 1B - temperature sensitive mutation (can have darker hairs on cooler sites) Types 2-7 Almost all AR
Hermansky-Pudklak features
Disorder of melanosome synthesis Dilution of hair/eye/skin pigmentation Bleeding diathesis Interstitial pulmonary fibrosis Granulomatous colitis
Chediak Higashi
Disorder of melanosome synthesis Dilution of hair/skin/eyes pigment Immune dysfunction Bleeding diathesis Neurological (cerebellar syndrome)
Cross syndrome
South African
Pigment dilution
Griscelli Syndrome
Disorder of melanosome transport
Hair + skin pigment dilution
Neurological changes
immunological dysfunction
Woolf syndrome
Deaf WOOOOOOOLF
congenital deafness + partial OCA
Hypomelanosis of Ito
mental retardation skeletal anomalies linear naevoid hypopigmentation chromosomal mosaicism Extracutaneous occurs in 15%
DDx CALMS
MMaFS BITCH GANG
Maffucci, McCune Albright, Fanconi anaemis, Bloom syndrome, Idiopathic, TS, Chediak Higashi, Gorlin, Ataxia telangiectasia, NF, Gaucher
DDx linear hypopigmentation
CHIILL MEG (Blaschkoid distribution) - Conradi, hypomelanosis of Ito, IP, Lichen striatus, lichen sclerosus, menkes, epidermal naevus, Goltz
DDx guttate leukoderma
Idiopathic guttate hypomelanosis Confetti spots in TS PLC LS vitiligo Darier disease XP pityriasis alba tinea versicolor leukoderma punctata - after PUVA
Incontinentia Pigmenti
- inheritance + gene
- histology
XLD (lethal in males)
IKBKG (same gene hypohidrotic ectodermal dysplasia w immunodef)
Histo - early eosinophilic spongiosis –> acanthosis + dyskeratosis –> pigment incontinence, basal vacuolation –> epidermal atrophy, loss adnexal structures
Incontinentia pigmenti
- clinical features - cutaneous
Stage 1 vesiculobullous - present at birth/ first 2 weeks
Stage 2 verrucous - within first few months
Stage 3 hyperpigmented - occurs within first year (minority can be born in this stage)
stage 4 hypopigmented - adolescence through adulthood
Incontinentia pigmenti
- clinical features - extracutaneous
malignancy risk - rhabdomyosarcoma, paratesticular, retinoblastoma, leukaemia, Wilm’s tumour
Teeth - delayed, cone-shaped
Eyes - strabismus, cataracts, microphthalmia
Nails - onychodystrophy
Hair - cicatricial alopecia
CNS - seizures, microcephaly, intellectual impairment
MSK - skull/scoliosis
Reticulate hyperpigmentation DDx
Dowling Degos / Galli Galli Naegelli-Franchescetti-Jadasshon Dyskeratosis Congenita Fanconi Anaemia Reticulate acropigmetnation of Kitamura Confluent + reticulated papillomatosis (Gougerot + Carteaud) Erythema ab igne Prurigo pigmentosa (Keto diet) Atopic dirty neck Pityriasis versicolor PIH
Dyskeratosis congenita features
PPK (diffuse) Leukoplakia Reticulate pigmentation chest/neck/prox limbs) Nail dystrophy BM dysplasia
Fanconi anaemia
more generalised hyperpigmentation (less reticulate compared to DC) CALMs can be present Haem changes Increased risk cancers Short stature
