Genoderms Flashcards
PXE gene + inheritance
ABCC6 - AR
Pathophysiology + histology of PXE
Abnormal mineralisation of tissues - calcification of elastic fibres (stain VVG + Von Kossa)
Histology - clumped/frayed/degenerate elastic fibres in dermis
Clinical features of PXE
Chicken are Mental - COGO
- chicken skin - begins teenage years cobblestone, yellow colour, neck, under clavicles, axillae, groin, abdomen, perineum, thighs
- can occur soft palate, gingival mucosa
- mental chin exaggerated
- Cardiovascular - calcification - claudication, HTN, atherosclerosis, aneurysm
- ocular - angioid (Bruch’s membrane), peau d’orange changes - can impact vision
- GIT - bleeding
- Obstetric - miscarriage (unconfirmed)
Subtypes Ehlers Danlos
I, II - classical COL5A1 III - hypermobile TNXB IV - vascular COL3A1 -- these are all AD then the rest are XL/AR....
Buschke-Ollendorf
Also known as dermatofibrosis lenticularis disseminata
AR inheritance - LEMD3
juvenile elastomas, collagenomas, osteopoikilosis, short stature, DM
COLD DEERS (hiding in the bush) - collagenomas, osteopoikilosis, LEMD3, deafness, DM, elastomas, eyes, recessive inheritance, short stature
Cowden Syndrome
PALPaTE and Feel Behind The GUM
- papillomatosis
- acral keratoses
- lipomas
- punctake PPK
- trichilemommas
- epidermoid cysts
- fibromas (storiform collagenomas)
- Breast Ca
- Thyroid Ca
- GIT Ca
- Uterine Ca
- melanoma
Epidermal naevus syndromes
Sebaceous Polyps Feel A Bit Pimply - CFCC
- schimmelpenning (linear naevus sebaceous)
- phacomatosis pigmentokeratotica (sebaceous naevus + naevus spilus)
- follicular naevus syndrome (ipsilateral cataracts, MSK, neurological)
- angora hair naevus syndrome (neuro)
- Becker’s naevus syndrome (ipsi breast hypoplasia)
- Proteus (PIK3A/AKT, slow flow vascular, lipomas, cerebriform connective tissue naevi)
- Cowden’s
- FGFR (neuro)
- CLOVES
- CHILD
Note that the majority of epidermal naevi in Blaschko distribution
Classification of epidermal naevi
Keratinocytic, sebaceous, follicular, eccrine/apocrine
What is the significance of epidermolytic subtype of keratinocytic naevi?
KRT1, 10 gene, may be gonadal involvement –> risk of child with epidermolytic ichthyosis
CHILD syndrome inheritence + features
XL dominant
Congenital Hemidysplasia, ichthyosis + limb defect
Sharp midline cut off w keratinocytic/ verrucous epidermal naevi
– 2 patterns - naevus is either lateralised or in Blaschko’s lines
CLOVES syndrome gene + features
PIK3CA (same as Klippel Trenauny)
Congenital lipomatus overgrowth, vascular malformation epidermal naevus, skeletal malformation
Classification of congenital melanocytic naevi?
Small < 1.5cm
Medium 11.5-20cm
Giant > 20cm
What are the 2 types of proliferative nodules in congenital melanocytic naevi?
- benign proliferating nodule (present at birth, symmetrical, well circumscribed, firm, uniform colour)
- neuroid proliferation (not present at birth, develop during childhood, grow slowly, poorly defined, can become pendulous)
What are the possible complications of CMN + how to assess risk?
Psychological/ cosmetic
Neurological
Melanoma
Rhabdomyosarcoma
Risk factors = multiple satellite lesions, > 40cm predicted adult size, posterior axial location
MRI w contrast before 6 months of age
Outline the assessment + Ix needed in an infant with > 2 CMN
Full history (particularly neurodevelopmental)
Full skin examination including palpation, lymph nodes
MRI w contrast before 6/12 of age
—- if normal, then anual clinical review unless new symptoms
—- if intraparenchymal, then risk of seizures/ ADHD etc but no further imaging monitoring required
—- all other MRI findings require interval monitoring
What is the risk of melanoma in CMN?
If small, single, then no added risk for melanoma
With added risk factors, risk can increase to 10-15%
Overall, risk is around 0.1-2.9% (for all CMN)
How would you manage an infant with CMN?
Assess history/ examination Ix (MRI) Explanation of diagnosis, predicted progression/ complications to family Photography to assist with monitoring Monitoring at least every year Discussion regarding surgery (depends on size/ cosmetic concerns) - doesn't change risk of mm Hair removal - shave/ wax/ depilatory Camouflage - note that colour will fade over time (can become quite light) Sun protection Self-monitoring Laser/ dermabrasion is controversial Support groups online
What is the classification for aplasia cutis congenita?
1 - isolated 2 - Adams Oliver (limb defect, CMTC, syndactyly, cardiac, neurodevelopmental) 3 - epidermal naevus 4 - underlying congenital malformation 5 - mummified twin/ placental infarct 6 - EB assoc (Bart) 7 - isolated on a limb 8 - maternal teratogen/infection/ condition --- DRUG = Missing Cutis Causes HAVOC (misoprostol, cocaine, Carbimazole, heparin, ACEi, Valproic acid, Other (infection), Clots (antiphospholipid synd) 9. GOLTZ
