NEET-PG 2015 - Dermatology PYQs Practice Questions

Q: Phrynoderma is primarily associated with a deficiency of which of the following?

Vitamin A. ***Vitamin A*** - **Phrynoderma** (toad skin) has been **classically attributed to vitamin A deficiency** in traditional medical literature and was the accepted answer in historical examinations. - It presents as **follicular hyperkeratosis** with dry, scaly, rough skin having prominent hair follicles with a sandpaper-like texture. - However, **modern evidence** suggests phrynoderma is a **multifactorial condition** often involving **multiple nutritional deficiencies**, with vitamin A being one important contributor among others. *Essential fatty acid* - Deficiency of **essential fatty acids** (linoleic and alpha-linolenic acid) causes **skin dryness, flakiness, and follicular hyperkeratosis**. - **Recent studies** indicate EFA deficiency may play a **significant role** in phrynoderma, particularly in developing countries where multiple nutritional deficiencies coexist. - The clinical presentation can closely mimic vitamin A deficiency-related skin changes. *Vitamin D* - Deficiency of **vitamin D** primarily causes **rickets** in children and **osteomalacia** in adults with bone pain, muscle weakness, and skeletal deformities. - While vitamin D has roles in skin health, its deficiency does not directly cause the follicular hyperkeratosis characteristic of phrynoderma. *Niacin* - **Niacin (vitamin B3)** deficiency causes **pellagra** with the classic \"3 Ds\": **dermatitis, diarrhea, and dementia**. - Pellagra dermatitis is typically **symmetrical in sun-exposed areas** with redness, scaling, and hyperpigmentation—distinctly different from the follicular pattern of phrynoderma. [Practice more Dermatology PYQs on OnCourse]

Q: HLA-Cw6 is associated with

Psoriasis vulgaris. ***Psoriasis vulgaris*** - **HLA-Cw6** is the **strongest genetic risk factor** associated with an increased susceptibility to psoriasis vulgaris, particularly early-onset forms. - Its presence is linked to a more severe and widespread presentation of the disease. *Myasthenia gravis* - This autoimmune disorder is primarily associated with **HLA-DR3** and **HLA-B8**, and autoantibodies against the acetylcholine receptor. - While other HLA alleles may be involved, **HLA-Cw6** is not a primary or strong genetic association for myasthenia gravis. *Behcet's disease* - **HLA-B51** is the most significant genetic association with Behcet's disease, particularly in populations of Middle Eastern and East Asian descent. - Symptoms include **recurrent oral and genital ulcers**, **uveitis**, and skin lesions. *Pemphigus vulgaris* - This autoimmune blistering disease is strongly associated with **HLA-DR4** and **HLA-DRw6**, especially in individuals of Jewish descent. - It involves autoantibodies targeting **desmoglein 1 and 3**, leading to acantholysis within the epidermis. [Practice more Dermatology PYQs on OnCourse]

Q: Which area is typically not involved in a chickenpox rash?

Palms and soles. ***Palms and soles*** - The chickenpox rash, caused by the **varicella-zoster virus**, typically spares the palms and soles. - Chickenpox exhibits a characteristic **centripetal distribution** (center-predominant), with lesions most numerous on the trunk and progressively fewer on the extremities. - **Sparing of palms and soles** is a classic differentiating feature from other viral exanthems like hand-foot-and-mouth disease. *Trunk* - The **trunk** is usually the **most heavily involved area** in a chickenpox rash, with lesions often appearing first and being most numerous here. - This is the hallmark of the characteristic **centripetal distribution** of the rash. *Axilla* - The **axilla** is a common site for chickenpox lesions due to its location on the trunk and the presence of **warm, moist skin folds** that can favor lesion development. - The rash tends to be widespread, making secondary sites like the axilla commonly involved. *Back* - The **back** is a major part of the trunk and is therefore extensively involved in a chickenpox rash. - The rash often starts on the trunk and spreads outwards, ensuring significant involvement of the back. [Practice more Dermatology PYQs on OnCourse]

Q: In which part of the body are lesions of Kaposi sarcoma most commonly seen?

Lower extremities. ***Lower extremities*** - Kaposi sarcoma lesions most frequently appear on the **skin of the lower extremities**, especially the feet and ankles. - This predilection is thought to be due to increased **venous stasis** or other local factors. *Upper extremities* - While Kaposi sarcoma can affect the upper extremities, it is a **less common primary site** compared to the lower limbs. - Lesions here are more likely to appear as the disease **progresses or disseminates**. *Torso* - Kaposi sarcoma lesions can occur on the torso, particularly on the **trunk**, but it is not the most common initial presentation. - Visceral involvement of the **gastrointestinal tract** and lungs can often present without skin lesions on the torso. *Head and neck* - Lesions of Kaposi sarcoma can appear on the head and neck, especially on the **face and oral cavity**, particularly in classic Kaposi sarcoma or in individuals with advanced immunosuppression. - However, this is still **less frequent** than involvement of the lower extremities. [Practice more Dermatology PYQs on OnCourse]

Q: All of the following are premalignant conditions except which of the following?

Pyoderma Gangrenosum. ***Pyoderma Gangrenosum*** - This is a **neutrophilic dermatosis** characterized by rapidly enlarging, painful ulcers with undermined, violaceous borders. It is an inflammatory condition, not premalignant. - While often associated with systemic diseases such as **inflammatory bowel disease** or **rheumatoid arthritis**, it does not inherently carry an increased risk of developing into skin cancer. *Bowen's Disease* - This is a form of **squamous cell carcinoma in situ**, meaning the cancerous cells are confined to the epidermis and have not yet invaded the dermis. - It is considered a **premalignant lesion** because it has the potential to progress to invasive squamous cell carcinoma if left untreated. *Actinic Keratosis* - These are **rough, scaly patches** on the skin caused by years of sun exposure, predominantly in fair-skinned individuals. - Actinic keratoses are considered **premalignant lesions** with a risk of transforming into invasive squamous cell carcinoma. *Xeroderma Pigmentosum* - This is a rare, **autosomal recessive genetic disorder** characterized by a defect in DNA repair mechanisms, specifically nucleotide excision repair. - Individuals with xeroderma pigmentosum have an extremely high risk of developing various **skin cancers** (basal cell carcinoma, squamous cell carcinoma, melanoma) at an early age due to their inability to repair UV-induced DNA damage. [Practice more Dermatology PYQs on OnCourse]

Question 1

Phrynoderma is primarily associated with a deficiency of which of the following?

Accepted Answer

Vitamin A

Answer

Essential fatty acid

Answer

Vitamin D

Answer

Niacin

Question 2

HLA-Cw6 is associated with

Accepted Answer

Psoriasis vulgaris

Answer

Behcet's disease

Answer

Pemphigus vulgaris

Answer

Myasthenia gravis

Question 3

Which area is typically not involved in a chickenpox rash?

Accepted Answer

Palms and soles

Answer

Trunk

Answer

Axilla

Answer

Back

Question 4

In which part of the body are lesions of Kaposi sarcoma most commonly seen?

Accepted Answer

Lower extremities

Answer

Upper extremities

Answer

Torso

Answer

Head and neck

Question 5

All of the following are premalignant conditions except which of the following?

Accepted Answer

Pyoderma Gangrenosum

Answer

Bowen's Disease

Answer

Xeroderma Pigmentosum

Answer

Actinic Keratosis

Question 6

What condition is suggested by eyelid papules and a hoarse cry in a child?

Accepted Answer

Lipoid proteinosis

Answer

Croup

Answer

Acrodermatitis enteropathica

Answer

Congenital syphilis

Question 7

In which of the following conditions is phototherapy, specifically ultraviolet light therapy, useful for treatment?

Accepted Answer

Psoriasis

Answer

Tinea corporis

Answer

Pemphigus

Answer

PMLE

Question 8

Acanthosis nigricans is characterized by all of the following except?

Accepted Answer

Histologically there is hypermelanosis

Answer

Associated with thick skin with hyperpigmentation

Answer

May be a sign of internal malignancy

Answer

Common in obese people

Question 9

Which of the following organisms has a role to play in Seborrheic dermatitis?

Accepted Answer

Pityrosporum ovale

Answer

Propionibacterium

Answer

Candida albicans

Answer

None of the above

Question 10

Pruritus is a feature of which of the following conditions?

Accepted Answer

Bullous pemphigoid

Answer

Pemphigus foliaceous

Answer

Pemphigus vulgaris

Answer

None of the options

NEET-PG 2015 — Dermatology