47 - The Ichthyosis Flashcards
1
Q
Parental consanguinity may suggest _____ inheritance
A
Autosomal recessive
2
Q
Chorionic villous sampling performed in the
A
1st trimester
3
Q
Amniocentesis performed in the
A
2nd trimester
4
Q
Symptoms of salicylic acid intoxication
A
Nausea
Tinnitus
Dyspnea
Hallucinations
5
Q
Most common ichthyosis
A
Ichthyosis vulgaris
6
Q
Gene mutation and protein: ichthyosis vulgaris
A
FLG
Filaggrin
7
Q
Scale is usually most prominent on the extensor surfaces of the extremities, with flexural sparing
Diaper area tends to be spared
A
Ichthyosis vulgaris
8
Q
Mode of inheritance: ichthyosis vulgaris
A
Autosomal semidominant
9
Q
Associated findings include hyperlinear palms, palmar/plantar thickening, keratosis pilaris, atopy
A
Ichthyosis vulgaris
10
Q
Gene mutation and protein: X-linked recessive ichthyosis
A
STS
Steroid sulfatase
11
Q
Scaling is most prominent on the extensor surfaces, with significant involvement of the flexural areas
Comma-shaped corneal opacities
Increased risk of cryptorchidism and testicular cancer
A
X-linked recessive ichthyosis
12
Q
Steroid sulfatase hydrolyzes sulfate esters, which include
A
Cholesterol sulfate
Sulfated steroid hormones
13
Q
Absence of steroid sulfatase enzyme in the fetal placenta leads to
A
Low maternal urinary estrogens
Failure of labor to initiate or progress normally
14
Q
Majority of maternal urinary estrogens are derived from the
A
Fetal adrenal glands
15
Q
During the first _____ of life, the collodion membrane breaks up and peels off
A
2 weeks
16
Q
Types of autosomal recessive congenital ichthyosis
A
- Lamellar ichthyosis
- Congenital ichthyosiform erythroderma
- Harlequin ichthyosis
- Netherton syndrome
17
Q
ARCI:
Large, dark, platelike scales
Infants may be red at birth, adults have little to no erythroderma
Ectropion, eclabium
Scarring alopecia most prominent at the periphery
A
Lamellar ichthyosis
18
Q
ARCI:
Generalized redness and fine, white scales
Little to no ectropion, eclabium or alopecia
A
Congenital ichthyosiform erythroderma
19
Q
Gene mutation and protein: lamellar ichthyosis
A
TGM1
Transglutaminase 1
20
Q
Bathing suit ichthyosis is a type of
A
Lamellar ichthyosis
21
Q
Thick, shiny plates of stratum corneum separated by deep, red fissures that tend to form geometric patterns
Poorly developed or absent ears
Marked ectropion and eclabium
Fingertips are tapered with hyperconvexity of the nails
A
Harlequin ichthyosis
22
Q
Ichthyosis linearis circumflexa
Trichorrhexis invaginata
Atopy
A
Netherton syndrome
23
Q
Polycyclic, serpiginous, migratory, double-edged scale at the margins of erythematous plaques
A
Ichthyosis linearis circumflexa
24
Q
Distal hair segment is telescoped into the proximal one
Also known as “bamboo hair”
A
Trichorrhexis invaginata
25
Trichorrhexis invaginata is caused by abnormal cornification of the
Inner root sheath
26
Trichorrhexis invaginata is more commonly observed on
Eyebrow hair
27
Gene mutation and protein: congenital ichthyosiform erythroderma
ALOXE3 - lipoxygenase 3
| ALOX12B - 12(R)-lipoxygenase E3
28
Gene mutation and protein: Harlequin ichthyosis
```
ABCA12
Adenosine triphosphate (ATP)-binding cassette (ABC) transporter
```
29
Normal lamellar granules are not found
Small vesicles that lack internal structure
No evidence of the lipid lamellar that form between granular and cornified cells
Harlequin ichthyosis
30
Gene mutation and protein: Netherton syndrome
```
SPINK5
LEKTI (lymphoepithelial Kazal-type related inhibitor
```
31
Topical and systemic retinoids should be avoided in patients with _____ because they can further exacerbate the condition
Netherton syndrome
32
Types of keratinopathic ichthyosis
1. Epidermolytic ichthyosis
2. Superficial epidermolytic ichthyosis/ichthyosis bullosa of Siemens
3. Ichthyosis hysterix Curth-Macklin
4. Annular epidermolytic ichthyosis
5. Ichthyosis with confetti
33
Mode of transmission: epidermolytic ichthyosis
Autosomal dominant
34
Presents at birth with blistering, redness and peeling
Generalized hyperkeratosis
Characteristic odor, thought to be related to superinfection by mixed flora
Corrugated scale that becomes accentuated in areas of body folds
Epidermolytic ichthyosis
35
Variant of epidermal nevus caused by a postzygotic spontaneous mutation
Hyperkeratosis alternating with normal skin distributed in streaks along Blaschko lines
Linear ichthyosiform erythroderma
36
Mode of transmission: superficial epidermolytic ichthyosis
Autosomal dominant
37
Corrugated hyperkeratosis, particularly over flexural areas
Loss of the uppermost epidermis (predominantly the stratum corneum), yielding a characteristic collarette-like depressed area that has been described as “mauserung” (molting)
Superficial epidermolytic ichthyosis
38
Gene mutation and protein: superficial epidermolytic ichthyosis
KRT2
| Keratin 2
39
Mode of inheritance: annular epidermolytic ichthyosis
Autosomal dominant
40
Severe, intermittent scaling and blistering resolves during puberty
Residual, limited plaques with corrugated scale and erythema primary in flexural and intertriginous skin
Widespread, migratory, polycyclic, and annular scaling plaques
Annular epidermolytic ichthyosis
41
Gene mutation and protein: annular epidermolytic ichthyosis
KRT10, KRT1
| Keratins 10 and 1
42
On electron microscopic examination, clumping of filaments is observed to begin in the first suprabasal layer
Epidermolytic ichthyosis
43
Congenital erythroderma, malformation of the auricle, tapering of the digits
Palmoplantar keratoderma
Small islands of normal-appearing skin beginning in childhood
Ichthyosis with confetti
44
Severe palmar/planes involvement implies mutations in
KRT1
45
Occurs only in the suprabasal epidermis of palmar and plantar skin
KRT9
46
Does not feature marked skin fragility
| No evidence of filament aggregates
Ichthyosis with confetti
47
Connexin disorders include
Keratitis-ichthyosis-deafness syndrome
| Erythrokeratodermia variabilis et progressiva
48
Well-demarcated, erythematous, hyperkeratotic plaques that are symmetrically distributed over the extremities and buttocks, and often the face
Trunk tends to be spared
Erythrokeratodermia variabilis et progressiva
49
Mode of inheritance: erythrokeratodermia variabilis et progressiva
Autosomal dominant
50
Hyperkeratosis, acanthosis, papillomatosis, capillary dilatation
Severe papillomatosis and suprapapillary thinning may result in a “church spire” appearance
Erythrokeratodermia variabilis et progressiva
51
Mode of inheritance: keratitis-ichthyosis-deafness syndrome
Autosomal dominant
52
Distinctive plaques may have a discrete border and a verrucous appearance with crusting and may be conspicuously figurate and symmetric on the face
Prominent follicular hyperkeratosis which can result in scarring alopecia
“Leather-like” palmar/plantar keratoderma
Keratitis-ichthyosis-deafness syndrome
53
Gene mutation and protein: erythrokeratodermia variabilis et progressiva
GJB3, GJB4, GJA1
| Connexin 31, 30.3, 43
54
Family of proteins that aggregate to form gap junctions that are important channels for intercellular communication
Connexins
55
Gene mutation and protein: keratitis-ichthyosis-deafness syndrome
GJB2
| Connexin 26
56
Oral retinoids has been reported to be of little benefit and possibly to exacerbate the corneal neovascularization
Keratitis-ichthyosis-deafness syndrome
57
Lack the generalized hyperkeratosis in most ichthyoses
Painless, easy peeling skin without scarring
Exacerbation by friction and humidity
First appearance from the second day to mid-first decade of life
Peeling skin disorders
58
Gene mutation and protein: PSS1
CDSN
| Corneodesmosin
59
Loss of _____ expression eliminates the adhesion between the upper epidermis and the stratum corneum and disrupts terminal differentiation
Corneodesmosin
60
Gene mutation and protein: PSS2
TGM5
| Transglutaminase 5
61
Expressed in the granular layer of skin
Central to the formation of the cornified envelop, cross-linking structural proteins including involucrin, loricin, filaggrin, and small proline-rich proteins
Transglutaminase 5
62
Gene mutation and protein: PSS3
Autosomal recessive mutations in CHST8
| N-acetylgalactosamine-4-O-sulfotrasferase
63
Enzyme central to the production of sulfated glycosaminoglycans in the epidermis
N-acetylgalactosamine-4-O-sulfotrasferase
64
Gene mutation and protein: PSS4
Autosomal recessive mutations in CSTA
| Cystatin A
65
Cysteine protease inhibitor expressed throughout the epidermis
Central role in desmosomal adhesion in basal layers
PSS4
66
Gene mutation and protein: PSS5
Autosomal recessive mutations in SERPINB8
| Protease inhibitor
67
Neutral lipid storage disease with ichthyosis
Chanarin-Dorfman syndrome
68
Mode of inheritance: Chanarin-Dorfman syndrome
Autosomal recessive
69
Accumulation of triglycerides in the cytoplasm of keratinocytes, leukocytes, muscle, liver, fibroblasts, and other tissues with normal blood lipid levels
Generalized lamellar scales
Corrugated accentuation of hyperkeratosis in flexures
Collodion baby
Chanarin-Dorfman syndrome
70
Gene mutation: neutral lipid storage disease without ichthyosis
PNPLA2
71
Extracutaneous involvement is more severe in neutral lipid storage disease with or without ichthyosis
More severe in neutral lipid storage disease without ichthyosis
72
Histopathology of oil red O or Sudan III stains shows lipid droplets in dermal cells and in acrosyringia of eccrine ducts
Chanarin-Dorfman syndrome
73
Gene mutation: Chanarin-Dorfman syndrome
ABHD5
74
CHILD syndrome is a rare disorder consisting of
Congenital hemidysplasia
Ichthysiform erythroderma
Limb defects
75
CHILD syndrome is found almost exclusively in
Females
76
Mode of inheritance: CHILD syndrome
X-linked dominant
77
Gene mutation and protein: CHILD syndrome
NSDHL (NADPH steroid dehydrogenase-like protein)
| 3beta-hydroxysteroid dehydrogenase
78
Functions in the post-squalene cholesterol biosynthetic pathway, catalyzing intermediate steps in the conversion of lanosterol to cholesterol
3beta-hydroxysteroid dehydrogenase
79
Improvement of skin findings in _____ was achieved by topical application of
Cholesterol
| Lovastatin
80
Also known as peroxisomal biogenesis disorder complentation group 11
Rhizomelic chondrodysplasia punctata
81
Mode of inheritance: rhizomelic chondrodysplasia punctata
Autosomal recessive
82
Dwarfism caused by symmetric shortening of the proximal long bones, specific radiologic abnormalities (ie, presence of stippled calcifications of cartilage, vertebral clefting), joint contractures, congenital cataracts, ichthyosis and severe mental retardation
Rhizomelic chondrodysplasia punctata
83
Symmetric shortening of the proximal bones
Rhizomelia
84
Gene mutation and protein: rhizomelic chondrodysplasia punctata
PEX7
| Peroxin 7
85
Gene mutation and protein: X-linked chondrodysplasia punctata
ARSE
| Arylsulfatase E
86
Conradj-Hunermann-Happle syndrome
X-linked dominant chondrodysplasia punctata
87
Mosaic pattern of skin involvement along Blashcko lines caused by mosaic X-chromosome inactivation (lyonization)
Occurs almost exclusively in females
Presents at birth as congenital ichthyosiform erythroderma that clears over months and is replaced by linear hyperkeratosis, follicular atrophoderma, and pigmentary abnormalities
X-linked dominant chondrodysplasia punctata
88
Gene mutation: X-linked dominant chondrodysplasia punctata
EBP (enopamil-binding protein)
89
Downstream of NSDLH in the cholesterol synthetic pathway
EBP
90
Gene mutation: ichthyosis follicularis, alopecia, and photophobia syndrome
MBTPS2
91
Polyhydramnios in the 2nd trimester
Premature delivery of infants with erythrodermic, edematous, caseous scaling skin resembling excessive vernix caseosa, respirating distress, and transient peripheral eosinophilia
Ichthyosis prematury syndrome
92
Gene mutation: ichthyosis prematury syndrome
FATP4 (fatty acid transport protein 4 gene)
93
Mode of inheritance: multiple sulfatase deficiency
Autosomal recessive
94
Gene mutation and protein: multiple sulfatase deficiency
Sulfatase modifying factor 1 (SUMF1)
| C alpha-formylglycine
95
Heredopathia atactica polyneuritiformis
Refsum disease
96
Rare, progressive, degenerative disorder of lipid metabolism resulting from the failure to break down dietary phytanic acid and its subsequent accumulation in tissues
Refsum disease
97
Mode of inheritance: Refsum disease
Autosomal recessive
98
Gene mutation and protein: Refsum disease
PAHX
| PhyH
99
Treatment of Refsum disease
Dietary restriction of foods containing phytanic acid and its precursors
100
Congenital ichthyosis - most involved areas are the sides and back of the neck, lower abdomen, and flexures
Spactic paralysis
Mental retardation
Presence of glistening white dots in the macula of the retina
Sjogren-Larsson syndrome
101
Mode of inheritance: Sjogren-Larsson syndrome
Autosomal recessive
102
Caused by fatty alcohol:NAD oxidoreductase deficiency
Sjogren-Larsson syndrome
103
Gene mutation: Sjogren-Larsson syndrome
ALDH3A2
104
Mode of inheritance: trichothiodystrophy
Autosomal recessive
105
Characteristic features of sulfur deficient, brittle hair that exhibits alternating birefringence (tiger tail banding) when viewed under polarizing microscopy
Trichothiodystrophy
106
Most common skin findings in trichothiodystrophy
Ichthyosis (65%)
| Photosensitivity (42%)
107
Gene mutation and protein: trichothiodystrophy
ERCC2
TFIIH
+other mutations
108
Y/N: Trichothiodystrophy patients have been observed to be at high risk for the development of skin cancer
No - have not been observed
109
Acquired ichthyosis has been described in association with
```
Malignancies
Drugs
Endocrine and metabolic disease
Malnutrition
HIV and other infections
Autoimmune conditions
```
110
Most common malignancy reported with acquired ichthyosis
Hodgkin disease
111
Type of acquired ichthyosis with sharply demarcated, round or oval scaly patches with hypo- or hyperpigmentation
Pityriasis rotunda
112
Confluent and reticulated papillomatosis of Gougerot and Carteaud are seen in
Young adults
113
Confluent and reticulated papillomatosis of Gougerot and Carteaud tend to be localized predominantly on the
Neck, upper trunk (intermammary and interscapular regions) and axillae
