NEET-PG 2024 - Dermatology PYQs Practice Questions

Q: A patient who has always neglected his nutrition presented with follicular hyperkeratosis on the extensor aspect of the forearm. What is the diagnosis?

Phrynoderma. ***Phrynoderma*** - **Phrynoderma**, also known as **toad skin**, is characterized by **follicular hyperkeratosis**, particularly on the **extensor surfaces** of limbs like the forearm. - This condition is closely linked to **nutritional deficiencies**, often involving **vitamin A**, **essential fatty acids**, or sometimes **B vitamins**. *Eruptive xanthoma* - **Eruptive xanthomas** are small, yellow-red papules that often appear suddenly, typically on the **buttocks**, **extensor surfaces of the limbs**, and **trunk**. - They are a cutaneous manifestation of **severe hypertriglyceridemia** and not primarily related to general nutritional neglect or follicular hyperkeratosis. *Darier's disease* - **Darier's disease** is a **rare, inherited genetic disorder** characterized by greasy, crusted papules primarily in **seborrheic areas** such as the scalp, forehead, chest, and groin. - It results from a mutation in the **ATP2A2 gene**, affecting calcium signaling in keratinocytes, and is not a nutritional deficiency condition. *Folliculitis* - **Folliculitis** is the inflammation of one or more **hair follicles**, often caused by **bacterial** (e.g., *Staphylococcus aureus*) or **fungal infections**. - It presents as small, red, sometimes pus-filled bumps around hair follicles, distinct from the dry, rough texture of follicular hyperkeratosis seen in phrynoderma. [Practice more Dermatology PYQs on OnCourse]

Q: A patient presents with painful vesicles as shown in the image. What is the diagnosis?

Herpes. ***Herpes*** - The image shows a cluster of **small, painful vesicles on an erythematous base**, which is highly characteristic of a herpes simplex virus (HSV) infection. - These lesions typically evolve into ulcers, crust over, and heal, and are often recurrent. *Chancroid* - Chancroid presents as **painful, soft chancres** (ulcers) with irregular, undermined borders and a gray or yellow base, often accompanied by **buboes** (enlarged, tender lymph nodes). - It does not typically manifest as clusters of small vesicles. *Syphilis* - Primary syphilis presents as a **painless chancre**—a single, firm, ulcerated lesion with a clean base and raised borders. - Secondary syphilis can cause a variety of skin manifestations, but not painful vesicles. *Candidiasis* - Cutaneous candidiasis usually appears as a **red, moist rash with satellite lesions** (smaller papules or pustules spreading from the main rash), often in skin folds. - While it can be inflammatory and itchy, it does not typically form discreet painful vesicles as seen in the image. [Practice more Dermatology PYQs on OnCourse]

Q: The skin biopsy shown below is most consistent with which of the following conditions? ![img-28.jpeg](img-28.jpeg)

Lichen planus. ***Lichen planus*** - The image shows **basal cell degeneration** (liquefaction degeneration), a **sawtooth rete ridge pattern**, and a band-like inflammatory infiltrate primarily composed of lymphocytes at the dermo-epidermal junction, which are classic histological features of **lichen planus**. - **Civatte bodies** (apoptotic keratinocytes forming colloid bodies) are typically present, resulting from keratinocyte damage at the basal layer. - These features make lichen planus the most consistent diagnosis. *Lichen nitidus* - Characterized by **"ball and claw" lesions**, which are small, localized epidermal invaginations enclosing a central infiltrate of lymphocytes and histiocytes. - The granulomatous infiltrate is more focal and circumscribed compared to the band-like pattern of lichen planus. - While both are interface dermatitides, the architectural pattern differs significantly. *Morphea* - This is a localized form of **scleroderma**, characterized by increased **collagen deposition**, thickening of the dermis, and loss of adnexal structures like hair follicles and sweat glands. - The inflammatory infiltrate is typically perivascular and interstitial, not band-like at the dermo-epidermal junction. - The image does not show features of dermal fibrosis or homogenization of collagen bundles expected in morphea. *Lupus erythematosus* - Also shows **interface dermatitis** with basal vacuolar changes and lymphocytic infiltrate. - However, lupus typically shows a **perivascular and periappendageal pattern** of infiltrate rather than the dense band-like pattern of lichen planus. - Additional features in lupus include dermal mucin deposition, thickened basement membrane (PAS-positive), and follicular plugging. - The dense, continuous band-like infiltrate and sawtooth rete ridges favor lichen planus over lupus. [Practice more Dermatology PYQs on OnCourse]

Q: A child presents with itchy lesions and diarrhea and has been advised to follow a gluten-free diet. What is the most likely etiology of this condition?

Celiac disease. ***Celiac disease*** - **Celiac disease** is an autoimmune condition triggered by **gluten ingestion**, leading to small intestine damage and nutrient malabsorption. - The combination of **itchy lesions** (dermatitis herpetiformis, a skin manifestation of celiac disease), **diarrhea**, and improvement on a **gluten-free diet** are highly characteristic. - Since the question asks for the **underlying etiology**, celiac disease is the correct answer as it causes both the skin and GI manifestations. *Whipple's disease* - This is a rare systemic infection caused by the bacterium **Tropheryma whipplei**, presenting with **arthralgia, fever, malabsorption, and lymphadenopathy**. - While it can cause diarrhea and malabsorption, it is not associated with itchy skin lesions and does not respond to a gluten-free diet. *Crohn's disease* - **Crohn's disease** is a type of inflammatory bowel disease affecting any part of the GI tract, causing **abdominal pain, diarrhea, and weight loss**. - It is not associated with dermatitis herpetiformis and does not improve with a gluten-free diet (though some patients may have gluten sensitivity). *Dermatitis herpetiformis* - **Dermatitis herpetiformis** is the **cutaneous manifestation of celiac disease**, presenting as intensely itchy, vesicular lesions. - While DH explains the itchy lesions in this case, it is a **symptom/manifestation**, not the underlying **etiology**—the root cause is celiac disease itself, which produces both the intestinal damage (diarrhea) and the skin manifestations (DH). [Practice more Dermatology PYQs on OnCourse]

Q: Identify the diagnosis based on the dermatology immunofluorescence (IF) image provided.

Dermatitis herpetiformis. ***Dermatitis herpetiformis*** - The immunofluorescence image shows **granular IgA deposits** at the **dermal papillae region**, which is characteristic of dermatitis herpetiformis. - This condition is strongly associated with **celiac disease** and presents with intensely pruritic papules and vesicles. *Pemphigus vulgaris* - Immunofluorescence in pemphigus vulgaris typically shows a **fishnet pattern** of IgG deposits throughout the **epidermis**, reflecting antibodies against desmoglein 3 and 1. - This pattern is an intercellular deposition, not granular at the dermal papillae. *Pemphigus foliaceus* - Similar to pemphigus vulgaris, pemphigus foliaceus also exhibits **intercellular IgG deposits** in the epidermis, but it is usually more superficial, targeting desmoglein 1. - The image does not show this intercellular epidermal staining. *Bullous pemphigoid* - Bullous pemphigoid is characterized by **linear IgG and C3 deposits along the dermal-epidermal junction** (basement membrane zone). - The image distinctly shows granular IgA, not linear IgG/C3, and specifically in the dermal papillae. [Practice more Dermatology PYQs on OnCourse]

Question 1

A patient who has always neglected his nutrition presented with follicular hyperkeratosis on the extensor aspect of the forearm. What is the diagnosis?

Accepted Answer

Phrynoderma

Answer

Eruptive xanthoma

Answer

Darier's disease

Answer

Folliculitis

Question 2

A patient presents with painful vesicles as shown in the image. What is the diagnosis?

Accepted Answer

Herpes

Answer

Chancroid

Answer

Syphilis

Answer

Candidiasis

Question 3

The skin biopsy shown below is most consistent with which of the following conditions?
![img-28.jpeg](img-28.jpeg)

Accepted Answer

Lichen planus

Answer

Lichen nitidus

Answer

Morphea

Answer

Lupus erythematosus

Question 4

A child presents with itchy lesions and diarrhea and has been advised to follow a gluten-free diet. What is the most likely etiology of this condition?

Accepted Answer

Celiac disease

Answer

Whipple's disease

Answer

Crohn's disease

Answer

Dermatitis herpetiformis

Question 5

Identify the diagnosis based on the dermatology immunofluorescence (IF) image provided.

Accepted Answer

Dermatitis herpetiformis

Answer

Pemphigus vulgaris

Answer

Pemphigus foliaceus

Answer

Bullous pemphigoid

Question 6

A patient's skin biopsy shows a box-shaped or square-shaped pattern of inflammatory infiltrate, as shown in the image. What is the most likely diagnosis?

Accepted Answer

Lichen planus

Answer

Lichen amyloidosis

Answer

Morphea

Answer

Lichen nitidus

Question 7

A patient presents with orange-hued skin lesions and hyperkeratotic palms and soles. A biopsy shows alternating parakeratosis and orthokeratosis. What is the most likely diagnosis?

Accepted Answer

Pityriasis rubra pilaris

Answer

Follicular psoriasis

Answer

Keratosis follicularis

Answer

Ichthyosis vulgaris

Question 8

A patient presents with annular, scaly plaques with perifollicular extension on the trunk. What is the most likely diagnosis?

Accepted Answer

Tinea

Answer

Psoriasis

Answer

Lichen planus

Answer

Pityriasis versicolor

Question 9

An adolescent male presents with severe acne lesions and sinus tracts. Which is the most effective drug for this condition?

Accepted Answer

Isotretinoin

Answer

Minocycline

Answer

Doxycycline

Answer

Topical dapsone

Question 10

A patient presents with skin lesions and erosions on the buccal mucosa. The immunofluorescence image is shown. What is the most likely diagnosis?

Accepted Answer

Pemphigus vulgaris

Answer

Bullous pemphigoid

Answer

Linear IgA disease

Answer

Dermatitis herpetiformis

NEET-PG 2024 — Dermatology