Dermatologist Certificate Pediatric and Special Population Dermatology 2

Question 1

What is the pathognomonic skin finding of Kawasaki disease in children?

Accepted Answer

Polymorphous exanthem with desquamation of fingertips in the recovery phase

Answer

Kawasaki disease features a polymorphous rash plus desquamation of the fingertips and toes beginning in the periungual region during the subacute phase (10–25 days after fever onset).

Question 2

Xeroderma pigmentosum (XP) results from defects in which cellular repair mechanism?

Accepted Answer

Nucleotide excision repair (NER) of UV-induced DNA damage

Answer

XP is caused by inherited mutations in nucleotide excision repair genes, leaving UV-induced pyrimidine dimers unrepaired, leading to early and multiple skin cancers and photosensitivity.

Question 3

Which congenital melanocytic nevus size poses the greatest risk of malignant melanoma transformation?

Accepted Answer

Giant CMN (>20 cm in adult equivalent size)

Answer

Giant congenital melanocytic nevi (>20 cm) carry the highest lifetime risk of melanoma transformation (estimated 5–10%) and are also associated with neurocutaneous melanocytosis.

Question 4

Gianotti-Crosti syndrome (papular acrodermatitis of childhood) is most commonly associated with which viral infection?

Accepted Answer

Epstein-Barr virus (EBV)

Answer

While historically associated with hepatitis B, Gianotti-Crosti syndrome in the US is now most commonly triggered by EBV infection, presenting with papular eruption on the face and extremities.

Question 5

What is the recommended treatment for head lice (Pediculosis capitis) when permethrin 1% has failed?

Accepted Answer

Oral ivermectin or topical spinosad/benzyl alcohol

Answer

Resistance to permethrin is widespread; second-line options include oral ivermectin, topical spinosad (Natroba), or benzyl alcohol (Ulesfia), which work through different mechanisms.

Dermatologist Certificate Practice Test

Dermatologist Certificate Practice Test

Dermatologist Certificate Pediatric and Special Population Dermatology 2