COMSAE Dermatology and Integumentary System 3

Question 1

A 25-year-old woman notices well-circumscribed patches of hair loss on the scalp. Examination reveals smooth scalp skin with 'exclamation point' hairs at the periphery of patches. Which is the most likely diagnosis?

Accepted Answer

Alopecia areata

Answer

Alopecia areata is an autoimmune condition causing well-demarcated patches of non-scarring hair loss with characteristic 'exclamation point' hairs at patch margins.

Question 2

A 70-year-old presents with tense bullae on the trunk and extremities. The Nikolsky sign is negative. Direct immunofluorescence shows linear IgG and C3 deposits at the dermoepidermal junction. Which is the most likely diagnosis?

Accepted Answer

Bullous pemphigoid

Answer

Bullous pemphigoid features tense subepidermal bullae with linear IgG/C3 at the BMZ, targeting BP180 and BP230 antigens; the Nikolsky sign is negative.

Question 3

A 30-year-old develops target-shaped lesions (concentric rings) on the palms and soles after a recent herpes simplex virus infection. There is no mucosal involvement. Which condition does this most likely represent?

Accepted Answer

Erythema multiforme minor

Answer

Erythema multiforme minor presents with classic targetoid lesions, typically triggered by HSV or Mycoplasma pneumoniae, without significant mucosal or systemic involvement.

Question 4

A 45-year-old immigrant presents with intense nocturnal pruritus. Examination reveals burrows in the finger web spaces and erythematous papules on the wrists and genitalia. Which pathogen is responsible?

Accepted Answer

Sarcoptes scabiei

Answer

Scabies is caused by Sarcoptes scabiei mite infestation; characteristic features are intense nocturnal pruritus, burrows in interdigital spaces, and involvement of genitalia.

Question 5

A 65-year-old presents with a dermatomal distribution of painful vesicles on an erythematous base on the right thorax. She had varicella as a child. Which antiviral should be initiated within 72 hours of onset?

Accepted Answer

Acyclovir

Answer

Herpes zoster (shingles) results from VZV reactivation; antiviral therapy with acyclovir, valacyclovir, or famciclovir within 72 hours reduces duration and risk of postherpetic neuralgia.

COMSAE - Comprehensive Osteopathic Medical Self-Assessment Examination Practice Test

COMSAE - Comprehensive Osteopathic Medical Self-Assessment Examination Practice Test

COMSAE Dermatology and Integumentary System 3