ABD - American Board of Dermatology Pediatric Dermatology Questions and Answers 1 — Questions and Answers
Question 1: A 3-month-old infant presents with a rapidly proliferating, 3 cm segmental hemangioma on the right cheek that is beginning to obstruct the visual axis. What is the most appropriate first-line treatment for this patient?
- Topical timolol
- Oral propranolol (Correct answer)
- Intralesional corticosteroids
- Watchful waiting
Correct answer: Oral propranolol
Oral propranolol is the first-line treatment for complicated infantile hemangiomas, such as those that are large, rapidly growing, located in high-risk areas like the face, or causing functional impairment (e.g., visual obstruction). Topical timolol is more appropriate for smaller, superficial hemangiomas. Intralesional corticosteroids are a secondary option, and watchful waiting is inappropriate given the lesion's location and functional risk.
Question 2: A 3-week-old neonate presents with multiple erythematous papules and pustules confined to the face and scalp. Examination reveals a complete absence of comedones. Which of the following is the most likely diagnosis?
- Neonatal cephalic pustulosis (Correct answer)
- Erythema toxicum neonatorum
- Neonatal acne
- Miliaria rubra
Correct answer: Neonatal cephalic pustulosis
Neonatal cephalic pustulosis is characterized by an inflammatory papulopustular eruption on the face and scalp, typically appearing around 2-3 weeks of age. The key distinguishing feature from true neonatal acne is the absence of comedones. It is thought to be an inflammatory reaction to Malassezia species. Neonatal acne presents with comedones, while erythema toxicum neonatorum appears earlier and has a different clinical appearance.
Question 3: Which of the following biologic agents is FDA-approved for the treatment of moderate-to-severe atopic dermatitis in children as young as 6 months old?
- Adalimumab
- Secukinumab
- Dupilumab (Correct answer)
- Ustekinumab
Correct answer: Dupilumab
Dupilumab, a monoclonal antibody that inhibits IL-4 and IL-13 signaling, is FDA-approved for treating moderate-to-severe atopic dermatitis in patients aged 6 months and older. Adalimumab, secukinumab, and ustekinumab are approved for other inflammatory conditions but are not the indicated first-line biologic for this age group with atopic dermatitis.
Question 4: An 8-year-old child is evaluated for multiple hypopigmented macules on the trunk that have been present since infancy. The examination reveals three ash-leaf spots, facial angiofibromas, and a shagreen patch on the lower back. This constellation of findings is most characteristic of which genetic disorder?
- Neurofibromatosis type 1
- Incontinentia pigmenti
- Tuberous sclerosis complex (Correct answer)
- Epidermolysis bullosa
Correct answer: Tuberous sclerosis complex
The combination of hypopigmented macules (ash-leaf spots), facial angiofibromas, and a shagreen patch are major cutaneous features highly characteristic of Tuberous Sclerosis Complex (TSC). Neurofibromatosis type 1 presents with cafe-au-lait macules and neurofibromas, while the other options have distinctly different cutaneous manifestations.
Question 5: A 2-year-old child develops an abrupt, symmetric, monomorphous eruption of skin-colored to erythematous papules on the face, buttocks, and extensor surfaces of the extremities. The trunk is relatively spared. The child had a mild upper respiratory infection one week prior. What is the most likely diagnosis?
- Hand, foot, and mouth disease
- Erythema multiforme
- Pityriasis rosea
- Gianotti-Crosti syndrome (Correct answer)
Correct answer: Gianotti-Crosti syndrome
Gianotti-Crosti syndrome, or papular acrodermatitis of childhood, is a post-viral exanthem characterized by a monomorphous papular eruption with a classic acral distribution (face, buttocks, extensors), typically sparing the trunk. The other conditions have different lesion morphologies and distributions; for example, erythema multiforme has target lesions, and pityriasis rosea primarily affects the trunk.
Question 6: A 9-month-old infant presents with a persistent, scaly, crusted rash in the scalp and axillae that has been unresponsive to topical corticosteroids and antifungals. Examination reveals yellowish-brown scaly papules with scattered petechiae within the plaques. Which diagnosis should be strongly considered?
- Psoriasis
- Langerhans cell histiocytosis (Correct answer)
- Scabies
- Acrodermatitis enteropathica
Correct answer: Langerhans cell histiocytosis
Langerhans cell histiocytosis (LCH) in infants can mimic severe seborrheic dermatitis, particularly in the scalp and intertriginous areas. The presence of petechiae or purpura within the lesions and the failure to respond to standard therapies are critical red flags for LCH. A skin biopsy is required for definitive diagnosis.
