Epidermolysis Bullosa Dan Flashcards
what are the 4 major types of EB?
Simplex
Junctional
Dystrophic
Kindler syndrome
T/F EB types share 3 features; Genetic transmission Skin fragility Blister formation
T
T/F there are >15 distinct clinical phenotypes of EB and >30 different proteins may harbour the causative gene mutation
F
numbers are the other way around
there are several genes for some of the proteins so there are more genes than there are proteins
T/F
EB affects;
20 per million live births
8 per million of the population
T
T/F
EB simplex has a suprabasal split
T
T/F
Junctional EB split is sublamina densa
F
Junctional EB split is in lamina lucida of BMZ
Dystrophic EB split is sublamina densa
T/F
In kIndler syndrome the level of the split is variable within the BMZ
T
T/F
Most cases of EB Simplex (EBS) are autosomal recessive
F
most AD
but several AR types esp EBS-MD and several rare types
What are the major subgroups of EBS?
Basal and suprabasal
Can also be divided as common and rare
T/F
In Junctional EB (JEB) the lamina densa remains firmly attached to the dermis and forms the base of the blisters
T
What are the subgroups of JEB?
Generalized or localized
Can also be divided as common and rare
JEB is almost always AR
T
one reported kindred AD
T/F
JEB is due to mutations in laminin332, BP230 or α6β4-integrin
F
laminin332, BP180 (collagen 17) or α6β4-integrin
remember 17, 18 (180) are the same
T/F
All dystrophic EB (DEB) is due to mutations in gene for collagen 17
F
collagen 7
What are the subtypes of DEB?
Dominant or Recessive
Can also be divided as common and rare
T/F
there are 3 most common subtypes in each of the 3 major categories of EB
T
What are the most common types of EBS?
EBS-generalized severe. Formerly Dowling-Meara
EBS-localized. Formerly Weber-Cockayne
EBS-Generalized intermediate. Formerly Koebner
T/F
the 3 most common types of EBS are all AD due to mutations in keratin 5 or 14
T
The one more common recessive types is EBS with muscular dystrophy (EBS-MD) due to plectin mutations
What are the most common types of JEB?
JEB-generalized severe. Formerly Herlitz
JEB-generalized intermediate
JEB-localized
generalized intermediate type includes types previously known as; JEB-non-Herlitz, JEB-gen other and Generalized Btrophic Benign EB (GABEB)
NB JEB-PA with pyloric atresia used to be considered a major group but is actually rare
What are the most common types of DEB?
DDEB-generalized. Formerly known as Pasini or Cockayne-Touraine type
RDEB-generalised severe. Formerly Hallopeau-Siemens
RDEB-generalised Intermediete. Formerly RDEB-non-Halllopeau-Siemens or RDEB-gen other
T/F
Kindler syndrome is a rare AD form of EB due to mutations in the Kindlin 1 gene which can alos be classes as a Poikilodermatous genodermatosis
F
AR
all the rest true
gene code is KIND1 AKA FERMT1
T/F
In Kindler syndrome skin cleavage occurs in mixed planes – within and/or beneath BMZ
T
T/F
Kindler syndrome can look like other classical types of EB esp JEB-PA or RDEB types or like other poikilodermas
T
What are the features of KIndler syndrome?
Photosensitivity
Skin atrophy & poikiloderma
Trauma-induced blistering – lessens with age
May have nail dystrophy and pseudosyndactyly and PPK
Mucosal inflammation and stenosis (oesophageal, anal, urethral, vaginal) – colitis, oesophagitis, gingival hypertrophy, ectropion
Increased risk of SCC of skin and mucosae after age 30
Mx is symptomatic like other EB types + strict photoprotection
What is ‘EB with congenital absence of skin’ formerly Bart syndrome?
Any type of EB with aplasia cutis congenita
e.g JEB-PA
Unusual for aplasia cutis congenita as involves acral sites rather than scalp
T/F
The genes involved in EBS encode major scaffold proteins of basal keratinocytes
T
True for basal types
Suprabasal types affect higher keratinocyte layers, just beneath SC
T/F
EB kids often don’t crawl
T
bottom shuffle and reach then start walking
T/F
atrophic scarring occurs in most cases of EB
F
Only in 15% of EBS cases
More in subtypes with BMZ destruction or with generalized cutaneous and extracutaneous disease e.g. RDEB
Reticulated hyperpigmented macules are seen in which type of EB?
EBS with mottled hyperpigmentation (EBS-MP)
similar appearance may be seen in EBS-AR exophilin 5
T/F
Scalp and lower leg lesions are typical of all forms of dystrophic EB
F
typical of Junctional EB
T/F
dystrophic or absent nails are common in JEB
T
exuberant granulation tissue is typical of which form of EB?
JEB esp gen sev (Herlitz)
What are the types of superficial EBS?
Acral peeling skin syndrome (APSS)
EBS superficialis
Acantholytic EBS
Skin fragility syndromes (3 syndromes)
What are the genes and inheritence for superficial EBS?
Autosomal recessive (except EBS-superficialis; inheritance unknown) Mutations in plakophilin-1, plakoglobin or desmoplakin or Transglutaminase 5 (APSS)
What are the 3 major skin fragility syndromes?
Desmoplakin deficiency (EBS-desmoplakin; skin fragility-woolly hair syndrome) Plakoglobin deficiency (EBS-plakoglobin; skin fragility-plakoglobin deficiency) Plakophilin deficiency (EBS-plakophilin; skin fragility-ectodermal dysplasia syndrome)
Grouped herpetiform blisters in arcuate or polycyclic arrangement are characterisitic of what type of EB?
EBS generalized severe (EBS-gen sev; Dowling Meara)
widespread when younger - resembles Hailey-Hailey
When older, blisters occur in clusters esp around fingertips and in mouth
Which types of EB get EB naevi?
EBS generalized severe EBS generalized intermediate JEB generalized intermediate - most at risk RDEB generalized severe RDEB generalized intermediate
Albopapuloid lesions are typical of which type of EB?
DDEB generalized
