8 - 48 - INHERITED PALMOPLANTAR KERATODERMAS

Question 1

most common form of diffuse keratoderma

Answer 1

Epidermolytic PPK (EPPK)

Question 2

most cases of Epidermolytic PPK (EPPK) esults from heterozygous mutations in what gene?

Answer 2

KRT9

Question 3

a form of autosomal recessive, progressive, diffuse, mutilating PPK with transgrediens caused by biallelic mutations in SLURP1

Answer 3

Mal de Meleda

Question 3

most common type of PPK in the **Asian population **and is characterized by diffuse, transgrediens, nonprogressive, nonmutilating PPK.

Answer 3

Nagashima-type PPK

Question 4

caused by mutations in TRPV3 (autosomal dominant or autosomal recessive inheritance) or MBTPS2 (X-linked recessive inheritance), is characterized by diffuse mutilating PPK with periorificial keratotic plaques.

Answer 4

Olmsted syndrome

Question 5

characterized by diffuse PPK, scleroatrophy, sclerodactyly, and occurrence of squamous cell carcinomas within atrophic skin.

Answer 5

Huriez syndrome

Question 6

autosomal recessive disorder caused by mutations in the gene CTSC encoding cathepsin C. It is characterized by diffuse PPK with transgrediens and severe progressive periodontitis.

Answer 6

Papillon-Lefevre syndrome

Question 7

Three morphological patterns of PPK

Answer 7

(1) diffuse PPK with uniform involvement of the entire palmoplantar surface;

(2)** focal PPK **with localized hyperkeratosis predominantly on pressure points that is further subdivided into areata or nummular type (oval lesions, mainly on the plantar surface) and striate type (longitudinal hyperkeratotic lesions extending from the palms along the volar surface of the fingers associated with focal to diffuse thickening of the plantar skin); and

(3) **punctate PPK **with multiple, discrete 1-mm to 1-cm round keratotic papules over the palms and soles.

Question 8

extension of hyperkeratosis onto the dorsal aspects of the fingers, toes, hands, feet, and flexor aspects of the wrists and heels

Answer 8

transgrediens

Question 9

constricting bands around digits

Answer 9

pseudoainhum

Question 10

Question 11

Question 12

• honeycomb-like PPK, starfish-like hyperkeratoses, prominent knuckle pads on the dorsal aspects of the hands, and pseudoainhum leading to autoamputation of the digits

*These signs, when associated with hearing impairment, are referred to as?

Answer 12

• LORICRIN KERATODERMA/ mutilating keratoderma with ichthyosis
• Vohwinkel syndrome

The two essential clinical features for establishing the diagnosis are the characteristic honeycomb-like keratoderma and generalized ichthyosis,

Question 13

PPK Bothnia type is an autosomal dominant disorder caused by mutations in what gene?

Answer 13

AQP5

Question 14

malignancies associated with Mal de Meleda

Answer 14

malignant melanoma and Bowen disease

Question 14

Mal de Meleda is caused by mutations in what gene?

Answer 14

SLURP1