Dermatologist Certificate Trivia 3 â Questions and Answers
Question 1: What term describes the genetic skin disorder characterized by absent or reduced melanin production due to tyrosinase deficiency?
- Oculocutaneous albinism (Correct answer)
- Vitiligo
- Piebaldism
- Chediak-Higashi syndrome
Correct answer: Oculocutaneous albinism
Oculocutaneous albinism results from mutations in genes such as TYR (tyrosinase), leading to absent or severely reduced melanin in skin, hair, and eyes.
Question 2: The phrase 'herald patch' is the classic initial presentation of which common self-limited skin eruption?
- Pityriasis rosea (Correct answer)
- Tinea corporis
- Guttate psoriasis
- Secondary syphilis
Correct answer: Pityriasis rosea
Pityriasis rosea classically begins with a single large 'herald patch' followed days to weeks later by a widespread Christmas-tree pattern eruption.
Question 3: Which vitamin, when severely deficient, causes pellagra with its classic triad of dermatitis, diarrhea, and dementia?
- Niacin (B3) (Correct answer)
- Riboflavin (B2)
- Pyridoxine (B6)
- Thiamine (B1)
Correct answer: Niacin (B3)
Pellagra results from niacin (vitamin B3) or tryptophan deficiency; the skin shows a photosensitive dermatitis in sun-exposed areas called casal necklace.
Question 4: Which skin signâyellowing of the sclerae and skinâmost commonly indicates which underlying metabolic process?
- Elevated serum bilirubin from hepatic or hemolytic disease (Correct answer)
- Elevated serum carotenoids from diet
- Iron deposition in hemochromatosis
- Lipid deposition in xanthomatosis
Correct answer: Elevated serum bilirubin from hepatic or hemolytic disease
True jaundice with scleral icterus reflects hyperbilirubinemia (>2â3 mg/dL) from liver disease or hemolysis, not dietary carotenoids.
Question 5: The Darier sign, elicited by stroking a lesion causing it to urticate and become raised, is pathognomonic for which condition?
- Mastocytosis (urticaria pigmentosa) (Correct answer)
- Dermatographism
- Bullous pemphigoid
- Lichen planus
Correct answer: Mastocytosis (urticaria pigmentosa)
Darier sign reflects mast cell degranulation in urticaria pigmentosa (cutaneous mastocytosis) upon physical stroking of the lesion.
Question 6: Which anatomic structure marks the junction between the epidermis and dermis and plays a key role in anchoring the two layers?
- Basement membrane zone (Correct answer)
- Stratum granulosum
- Rete pegs only
- Papillary dermis capillaries
Correct answer: Basement membrane zone
The basement membrane zone (dermal-epidermal junction) contains hemidesmosomes, laminin, and type IV collagen that anchor the epidermis to the dermis.
Question 7: What is the name of the embryological process by which melanocytes migrate from the neural crest to the epidermis?
- Neural crest cell migration (Correct answer)
- Gastrulation
- Epidermal stratification
- Dermal condensation
Correct answer: Neural crest cell migration
Melanocytes originate from neural crest cells that migrate during embryogenesis into the epidermis, dermis, and other tissues.
Dermatologist Certificate Trivia 3
What term describes the genetic skin disorder characterized by absent or reduced melanin production due to tyrosinase deficiency?