Dermatology Question Bank

Read the Dermatology Question Bank sample questions

1. 1.A nine- year-old girl presents with a three month history of severe persistent itching and skin lesions throughout most of her body physical examination revealed numerous 15 to 20mm papulonodular lesions over all the extremities and trunk with some confluence (see accompanying figure) crusting and lichenification also were observed no lesions were present on the face Based on the patient`s history and physical examination, which one of the following is the most likely diagnosis?

   • A.Psoriasis vulgaris.
   • B.Pemphigus vulgaris.
   • C.Severe atopic dermatitis.Correct
   • D.Lichen planus.

   Why: The combination of chronic intense pruritus, lichenification from scratching, and flexural/extremity involvement with sparing of the face in a child is classic for severe atopic dermatitis. Psoriasis gives well-demarcated silvery plaques, pemphigus causes flaccid bullae/erosions, and lichen planus shows violaceous flat-topped papules, none of which fit this itchy, lichenified, excoriated picture.

2. 2.A 50-year-old white woman presented with a rash that first erupted on her trunk three years earlier and never fully cleared ( see accompanying figure) The lesions became pruritic after a warm shower or strenuous physical exercise, but were otherwise asymptomatic. physical examination revealed many discrete erythematous papules spread over the abdomen, upper chest, and back. on vigorous rubbing of a papule, a wheal formed at the site. The patient did not have hepatosplenomegaly. gastroinestinal complaints. or any palpable lymphadenopathy Based on the patient`s history and physical examination, which one of the following is the correct diagnosis?

   • A.Lichen planus.
   • B.Pityriasis rosea.
   • C.Scabies.
   • D.Urticaria pigmentosa.Correct

   Why: Persistent reddish-brown papules that urticate (form a wheal) on rubbing — a positive Darier sign — are diagnostic of urticaria pigmentosa (cutaneous mastocytosis). Pruritus triggered by heat or exercise reflects mast-cell degranulation. The absence of a herald patch, burrows, or Wickham striae excludes pityriasis rosea, scabies, and lichen planus.

3. 3.A 54-year-old man with type 2 diabetes mellitus complained of asymptomatic, slowly enlarging,brownish plaques on the anterior surfaces of both lower legs (see accompanying figure) These lesions developed over the past three years, and various creams had failed to help. These reddish-brown plaques had depressed shiny centers, and dilated deep subcutaneous vessels could be seen through the atrophic skin. small ulcerations had recently developed on the involved skin. Given the patient`s medical history and the physical appearance of the lesions,which one of the following is the most likely diagnosis?

   • A.Granuloma annulare.
   • B.Erythema nodosum.
   • C.Pretibial myxedema.
   • D.Necrobiosis lipoidica.Correct

   Why: Yellow-brown atrophic plaques with shiny depressed centers and visible telangiectatic vessels on the shins of a diabetic, prone to ulceration, are characteristic of necrobiosis lipoidica (diabeticorum). Granuloma annulare lacks atrophy/telangiectasia, erythema nodosum produces tender nodules, and pretibial myxedema is firm and thyroid-related.

4. 4.A 67-year-old woman presented after three years of progressive hyperpigmentation, which was worse in the sun-exposed areas of her skin but involved sun-protected areas as well.Appropriate initial management of this patient may include all of the following except

   • A.Medication history.
   • B.Oral and genital examination.
   • C.General health history.
   • D.Nd:Yag laser treatment using 532 nm wavelength.Correct

   Why: Nd:YAG 532 nm laser is a treatment, not part of the initial diagnostic workup of progressive hyperpigmentation. Appropriate first steps are a medication history (drug-induced pigmentation), oral/genital examination, and a general health history to identify systemic causes.

5. 5.A 27-year-old man presents with a 10-year history of asymptomatic lesions on his hands and elbows. Hundreds of pinpont-sized, skin-colored papules appear on the dorsum of his hands and the extensor surface of his upper extremities (see accompanying figure) He is otherwise in good health and is not taking any medications.Based on the patient`s history and physical examination, which one of the following is the correct diagnosis?

   • A.Psoriasis.
   • B.Lichen nitidus.Correct
   • C.Lichen simplex chronicus.
   • D.Lichen planus.

   Why: Hundreds of tiny, uniform, skin-colored pinpoint papules on the dorsal hands and extensor arms in an asymptomatic young man are typical of lichen nitidus. Psoriasis is scaly and plaque-forming, lichen simplex chronicus is a lichenified pruritic plaque, and lichen planus papules are larger, violaceous and itchy.

6. 6.what is the most common presentation of mucous membrane involvement of EBV infection?

   • A.Buccal ulcers with superficial slough
   • B.Erosions of the gingivae
   • C.Plication of the tongue
   • D.Palatal petechiaeCorrect

   Why: Palatal petechiae at the junction of hard and soft palate are the most characteristic mucosal sign of EBV infectious mononucleosis. The other findings are not the typical EBV mucosal presentation.

7. 7.This medication is a source of anagen effluvium and can cause abrupt shedding of hair

   • A.ColchincineCorrect
   • B.Hydrochlorothiazide
   • C.Beta blockers
   • D.Calcium channel blockers

   Why: Colchicine causes anagen effluvium — abrupt shedding of actively growing (anagen) hairs by arresting mitosis in matrix cells, similar to cytotoxic agents. Thiazides, beta-blockers, and calcium-channel blockers are not classic causes of anagen effluvium.

8. 8.The most likely diagnosis

   • A.Dyshidrotic Eczema
   • B.Contact Dermatitis, Allergic
   • C.Erythrasma
   • D.Tinea PedisCorrect

   Why: Scaling and maceration of the feet, often interdigital with itching, point to tinea pedis (dermatophyte infection), confirmable by KOH. Dyshidrotic eczema shows deep vesicles, contact dermatitis follows an exposure pattern, and erythrasma fluoresces coral-red under Wood lamp.

9. 9.Most likely implicated

   • A.Topical calcineurin inhibitor
   • B.Topical corticosteroidCorrect
   • C.Topical doxepin
   • D.Topical pramoxine

   Why: Topical corticosteroids are the agents most commonly implicated in steroid-induced local effects (atrophy, telangiectasia, striae, perioral dermatitis). Calcineurin inhibitors, doxepin, and pramoxine do not cause these atrophic complications.

10. 10.Herpes gestationis is most commonly associated with which HLA?

    • A.HLA-DR3Correct
    • B.HLA-B27
    • C.HLA-B51
    • D.HLA-DR9

    Why: Herpes (pemphigoid) gestationis is strongly associated with HLA-DR3 (and DR4). It is not linked to the HLA-B27 (spondyloarthropathy) or the other listed alleles.