Dermatology

Question 1

Genetics of incontinenita pigmenti

Answer 1

X-linked dominant, majority female because usually lethal for males in utero

Question 2

Stages of skin lesions in incontinentia pigmenti (also known as Bloch-Sulzberger)

Answer 2

1. linear inflammatory vesicles
2. pigmented warts on red base
3. Macular, hyperpigmented, streaks and whorls on trunk and extremities
4. Linear hypopigmented streaks that are atrophic later in childhood

Question 3

PHACES syndrome

Answer 3

1. Posterior fossa brain malformations
2. facial Hemangiomas
3. cerebroArterial abnormalities
4. Cardiac anomalies (most commonly involving aorta)
5. Eye abnormalities
6. Sternal clefting

Question 4

What is Nevis of Ota and what do you have to look out for?

Answer 4

Unilateral blue-gray-brown patch on face in distribution of trigeminal nerve; increased risk of melanoma and if there is eye involvement consult ophthalmology to rule out glaucoma

Question 5

Genetics and mechanism in Xeroderma Pigmentosum

Answer 5

Autosomal recessive; DNA repair ability is decreased because of abnormally low endonuclease levels

Question 6

Leopard syndrome

Answer 6

Autosomal dominant
Lentigines, electrocardiographic conduction defects, ocular hypertelorism, pulmonary stenosis, abnormal genitalia, restriction of growth, deafness

Question 7

Peutz-Jeghers syndrome, genetic and symptoms

Answer 7

Autosomal dominant with variable expression
Mucocutaneous pigmentation typically on lips and buccal mucosa
In adolescence, increased risk of GI polyps (can lead to rectal bleeding, intussusception, anemia)

Question 8

Syndrome where you see nail hypertrophy

Answer 8

Rubinstein-Taybi

Question 9

Genetics and cause of x-linked ichthyosis

Answer 9

X-linked recessive, secondary to steroid sulfates deficiency, increased stratum corneum

Question 10

Genetics and cause of ichthyosis vulgaris

Answer 10

Autosomal dominant, decreased or absent granular layer, increased stratum corneum, defect in profiling expression

Question 11

Netherton’s disease

Answer 11

Abnormality of hair a hair circumflexa (“bamboo hair”), episodic skin changes after 2 years of age; typically without scalp hair; generalized scaling erythroderma, failure to thrive with hypernatremic dehydration, diarrhea, increased risk of infection