CDT Dermatologic Conditions & Diseases 3

Question 1

Erythema chronicum migrans, the hallmark rash of Lyme disease, is caused by which organism?

Accepted Answer

Borrelia burgdorferi

Answer

Borrelia burgdorferi, transmitted by Ixodes ticks, causes the expanding annular 'bull's-eye' rash of Lyme disease known as erythema migrans.

Question 2

A patient with HIV presents with violaceous nodules on the lower extremities. Which diagnosis should be considered first?

Accepted Answer

Kaposi sarcoma

Answer

Kaposi sarcoma, associated with HHV-8, presents as violaceous macules, plaques, or nodules and is strongly linked to HIV/AIDS.

Question 3

Necrobiosis lipoidica is most commonly associated with which systemic condition?

Accepted Answer

Diabetes mellitus

Answer

Necrobiosis lipoidica is strongly associated with diabetes mellitus, presenting as yellowish-brown plaques on the shins.

Question 4

What is the Koebner phenomenon?

Accepted Answer

Development of skin lesions at sites of trauma in susceptible individuals

Answer

The Koebner (isomorphic) phenomenon refers to the appearance of skin lesions characteristic of a disease at sites of cutaneous trauma, seen in psoriasis, vitiligo, and lichen planus.

Question 5

Which subtype of rosacea is characterized primarily by persistent facial erythema and telangiectasia without papules or pustules?

Accepted Answer

Erythematotelangiectatic rosacea

Answer

Erythematotelangiectatic rosacea (subtype 1) presents with central facial flushing, persistent erythema, and visible blood vessels without inflammatory lesions.

(CDT) Certified Dermatology Tech Practice Test

(CDT) Certified Dermatology Tech Practice Test

CDT Dermatologic Conditions & Diseases 3