NEET-PG 2013 - Dermatology PYQs Practice Questions

Q: Tinea cruris is caused by which of the following fungi?

Epidermophyton. ***Epidermophyton*** - **_Epidermophyton floccosum_** is one of the common dermatophytes responsible for causing **tinea cruris** (jock itch) and tinea pedis (athlete's foot). - **Note:** Tinea cruris can be caused by multiple dermatophytes including **_Trichophyton rubrum_** (most common), **_T. mentagrophytes_**, and **_E. floccosum_**. Among the options listed, Epidermophyton is the only dermatophyte that commonly causes tinea cruris. - Microscopic examination of skin scrapings shows **septate hyphae**, and it typically invades the stratum corneum but **not hair or nails**. *Trichosporon* - **_Trichosporon_** species cause **white piedra** (a fungal infection of the hair shaft) and can cause systemic infections in immunocompromised individuals. - It is **not a dermatophyte** and does not cause tinea cruris. *Microsporum* - **_Microsporum_** species are primarily associated with **tinea capitis** (ringworm of the scalp) and **tinea corporis** (ringworm of the body). - While Microsporum can occasionally involve skin in the groin region, it is **rarely implicated in classic tinea cruris** and is not considered a typical causative agent compared to Trichophyton or Epidermophyton species. *Candida* - **_Candida_** species (e.g., **_Candida albicans_**) cause candidiasis, which commonly presents as **intertrigo** in skin folds, oral thrush, or vaginal yeast infections. - While it can occur in the groin area (**candidal intertrigo**), it is **not a dermatophyte** and is distinctly different from tinea cruris, often presenting with **satellite lesions** and an intensely erythematous, macerated rash. [Practice more Dermatology PYQs on OnCourse]

Q: Which of the following statements is true about rhinophyma?

Acne rosacea. ***Acne rosacea*** - **Rhinophyma** is a severe form of **acne rosacea**, characterized by sebaceous gland hypertrophy and connective tissue hyperplasia on the nose. - It specifically represents the **phymatous subtype** of rosacea, which involves thickening of the skin. *Premalignant* - Rhinophyma itself is generally **not considered premalignant** to skin cancer. - While skin cancers like **basal cell carcinoma** can rarely occur within rhinophyma, the condition itself does not inherently transform into malignancy. *Common in alcoholics* - This is a **common misconception**; while often associated with heavy alcohol use, there is no direct causal link. - The development of rhinophyma is primarily driven by the underlying pathogenesis of **rosacea**, not alcohol consumption. *Fungal etiology* - Rhinophyma is primarily an inflammatory skin condition, not caused by **fungal infection**. - Its etiology is complex, involving genetics, environmental triggers, and vascular dysregulation, but **microbial involvement** is typically bacterial (e.g., Demodex mites) rather than fungal. [Practice more Dermatology PYQs on OnCourse]

Q: What is the condition characterized by the hypertrophy of sebaceous glands?

Sebaceous hyperplasia. ***Sebaceous hyperplasia*** - This condition is characterized by the **enlargement (hypertrophy)** of normal sebaceous glands, often appearing as yellowish-white papules with a central umbilication. - It commonly occurs on the **face of older adults**, particularly on the forehead and cheeks, and is a benign condition. *Rhinosporidiosis* - This is a **chronic granulomatous disease** caused by the fungus *Rhinosporidium seeberi*, primarily affecting the **mucous membranes** of the nose and nasopharynx. - It presents as **friable, polypoidal masses** with a characteristic "strawberry-like" appearance due to small white spots (sporangia), not sebaceous gland hypertrophy. *Tubercular infection* - A tubercular infection, particularly cutaneous tuberculosis, can manifest in various forms, including **lupus vulgaris**, scrofuloderma, or tuberculosis cutis verrucosa. - These presentations involve **granulomatous inflammation** and tissue destruction, not isolated hypertrophy of sebaceous glands. *Nasopharyngeal angiofibroma* - This is a **rare, benign, highly vascular tumor** that originates in the nasopharynx, predominantly affecting adolescent males. - It typically presents with symptoms like **epistaxis** and **nasal obstruction**, and is composed of fibrous and vascular tissue, not sebaceous glands. [Practice more Dermatology PYQs on OnCourse]

Q: Lines of Blaschko are related to?

Keratinocytes. ***Keratinocytes*** - **Lines of Blaschko** represent the migratory pathways of embryonic cells, primarily **keratinocytes**, in the skin. - These lines are not visible under normal conditions but become apparent in various **genetic skin disorders** where abnormal cells follow these specific patterns. *Blood vessels* - While blood vessels are extensively present in the skin, they do not follow the specific **migratory patterns** described by the Lines of Blaschko. - Their arrangement is more related to **vascular networks** and anatomical supply rather than embryonic cell migration. *Nerves* - **Nerves** in the skin have specific distributions, often following dermatomal patterns, which are distinct from the **Lines of Blaschko**. - Nerve distribution is related to their segmental origin from the **spinal cord**, not the migratory paths of epidermal cells. *Bones* - **Bones** are part of the skeletal system and are not found in the skin, making them unrelated to the **Lines of Blaschko**. - These lines describe epidermal cell migration, which is a feature of the **integumentary system**. [Practice more Dermatology PYQs on OnCourse]

Q: Which of the following conditions does NOT cause nail pitting?

Pityriasis Rosea. ***Pityriasis Rosea*** - This condition primarily affects the **skin**, causing a distinctive rash of oval, pinkish-red patches, often preceded by a **herald patch**. - It characteristically spares the **nails**, meaning nail pitting is not a feature of pityriasis rosea. - Nail changes are not associated with this self-limiting dermatosis. *Lichen planus* - **Nail lichen planus** can cause various nail changes, including **pitting**, longitudinal ridging, pterygium formation, and thinning of the nail plate. - It is an inflammatory condition affecting the skin, hair, nails, and mucous membranes. - Nail involvement occurs in approximately 10% of patients with cutaneous lichen planus. *Psoriasis* - **Nail psoriasis** is common, affecting up to 50% of patients with psoriasis, and **pitting is the most characteristic nail finding**. - Pitting appears as small punctate depressions on the nail surface due to defects in the proximal nail matrix. - Other nail changes include onycholysis (oil drop sign), subungual hyperkeratosis, and salmon patches. *Fungal infection* - **Onychomycosis** (fungal nail infection) typically causes **thickening, discoloration, onycholysis, and crumbling** of the nail. - **True nail pitting is NOT a characteristic feature** of fungal infections, as pitting results from defects in the proximal nail matrix, not fungal invasion. - Fungal infections affect the nail plate and bed differently, causing destruction rather than the punctate depressions seen in pitting. [Practice more Dermatology PYQs on OnCourse]

Question 1

Tinea cruris is caused by which of the following fungi?

Accepted Answer

Epidermophyton

Answer

Trichosporon

Answer

Microsporum

Answer

Candida

Question 2

Which of the following statements is true about rhinophyma?

Accepted Answer

Acne rosacea

Answer

Premalignant

Answer

Common in alcoholics

Answer

Fungal etiology

Question 3

What is the condition characterized by the hypertrophy of sebaceous glands?

Accepted Answer

Sebaceous hyperplasia

Answer

Rhinosporidiosis

Answer

Tubercular infection

Answer

Nasopharyngeal angiofibroma

Question 4

Lines of Blaschko are related to?

Accepted Answer

Keratinocytes

Answer

Blood vessels

Answer

Nerves

Answer

Bones

Question 5

Which of the following conditions does NOT cause nail pitting?

Accepted Answer

Pityriasis Rosea

Answer

Lichen planus

Answer

Fungal infection

Answer

Psoriasis

Question 6

A 25-year-old patient presents with chronic itchy, erythematous skin lesions on the flexural areas that have been recurring since childhood. The patient has a family history of asthma. Which of the following is the most important diagnostic criterion for the most likely diagnosis?

Accepted Answer

Chronic pruritic eczema with typical morphology and distribution

Answer

Personal or family history of atopy

Answer

Elevated serum IgE levels

Answer

Early age of onset (before 2 years)

Question 7

Which of the following causes non-cicatricial alopecia?

Accepted Answer

All of the options

Answer

Tinea capitis

Answer

SLE

Answer

Alopecia areata

Question 8

The Grattage test is used to diagnose which of the following conditions?

Accepted Answer

Psoriasis

Answer

Tinea capitis

Answer

Lichen planus

Answer

Pemphigus vulgaris

Question 9

What is the treatment of choice for lichen planus?

Accepted Answer

Topical corticosteroids

Answer

Systemic corticosteroids

Answer

Antihistamines

Answer

Acitretin

Question 10

Most common metal in contact allergic dermatitis is?

Accepted Answer

Nickel

Answer

Gold

Answer

Silver

Answer

Aluminum

NEET-PG 2013 — Dermatology