NEET-PG 2013 - Dermatology Practice Questions

Q: What is the treatment for granuloma inguinale?

Azithromycin. ***Azithromycin*** - **Azithromycin** is the recommended first-line treatment for **granuloma inguinale** (donovanosis) caused by *Klebsiella granulomatis*. - Current recommended regimens: **Azithromycin 1g orally once weekly** OR **500mg daily for at least 3 weeks** (until all lesions have completely healed). - Preferred due to excellent tissue penetration, good efficacy, and convenient dosing that improves patient compliance. *Tetracycline* - **Tetracycline** (500mg four times daily) was historically used but has been largely replaced by **doxycycline** (100mg twice daily) as the preferred tetracycline-class antibiotic. - While effective against *Klebsiella granulomatis*, it requires frequent dosing leading to poor adherence. - **Doxycycline** (not listed here) is actually considered a co-first-line option alongside azithromycin in current CDC guidelines. *Clarithromycin* - **Clarithromycin** is a macrolide antibiotic but is not a recommended first-line agent for granuloma inguinale. - Limited clinical data supports its use for this condition, and it is not included in standard treatment guidelines. - Azithromycin from the same macrolide class is preferred due to better-established efficacy. *Streptomycin* - **Streptomycin** is an aminoglycoside antibiotic primarily used for mycobacterial infections (e.g., tuberculosis, plague). - Not indicated for granuloma inguinale as *Klebsiella granulomatis* responds well to macrolides (azithromycin) and tetracyclines (doxycycline). - Requires parenteral administration and has significant toxicity concerns (ototoxicity, nephrotoxicity).

Q: Which type of leprosy does not involve nerve damage?

Indeterminate leprosy. ***Indeterminate leprosy*** - This is the earliest form of leprosy and often presents with only a **single skin lesion** and no demonstrable nerve damage. - Due to the minimal immune response, it can be difficult to classify and may progress to other forms if left untreated. *Tuberculoid leprosy* - Characterized by a **strong cell-mediated immune response** to *Mycobacterium leprae*, leading to significant nerve involvement [1]. - Patients typically present with well-demarcated, **hypopigmented patches** with definite **sensory loss** due to nerve damage [1]. *Borderline tuberculoid leprosy* - This form sits between tuberculoid and borderline lepromatous leprosy, showing features of both, including **nerve involvement** [2]. - It presents with a few to several skin lesions that are usually smaller and less clearly defined than tuberculoid lesions, often with **palpable nerves** and mild sensory loss [2]. *Lepromatous leprosy* - Characterized by a **weak or absent cell-mediated immune response**, leading to widespread bacterial proliferation and extensive nerve damage, often symmetrical [1]. - Patients show numerous, poorly defined skin lesions, nodules, and severe nerve involvement, which can result in significant **deformities** [2].

Q: A 15cm hyperpigmented macule on an adolescent male undergoes changes such as coarseness, growth of hair & acne. Diagnosis is?

Becker nevus. ***Becker nevus*** - A Becker nevus is a **hyperpigmented patch** that typically appears during adolescence in males, often on the shoulder or upper trunk. - It characteristically becomes **hairy (hypertrichosis)**, more coarse, and can develop acne within the lesion, particularly during puberty due to androgen sensitivity. *Melanocytic nevus* - While melanocytic nevi are hyperpigmented, they generally do not show the characteristic changes of **coarseness, significant hair growth, or acne** within the lesion during adolescence. - They are typically stable in size and texture after initial development, with changes raising concern for **melanoma**. *Sebaceous nevus* - A sebaceous nevus is a **congenital lesion** often appearing as a yellowish-orange, waxy, or bumpy patch, usually on the scalp or face. - It does not typically present as a large, flat hyperpigmented macule that develops hair and acne in adolescence; instead, it may become verrucous or develop tumors in adulthood. *Sebaceous adenoma* - A sebaceous adenoma is a **benign tumor** of the sebaceous glands, usually appearing as a small, solitary, flesh-colored to yellowish papule or nodule, especially on the face. - It is not typically seen as a large, hyperpigmented macule that grows hair and acne over a broad area, as described in the question.

Q: What is the most likely diagnosis for a 15 mm hyperpigmented lesion on the shoulder that is enlarging and has hair growing from it?

Becker nevus. ***Correct: Becker nevus*** This diagnosis is supported by the description of a **hyperpigmented lesion** that is **enlarging** and has **hair growing from it**, typically appearing during adolescence or young adulthood. **Becker nevus** often presents as an **irregular, hyperpigmented patch**, usually on the shoulder or upper trunk, and is characteristically associated with **hypertrichosis** (increased terminal hair growth). The combination of location (shoulder), enlargement, and hair growth in a 15 mm lesion is classic for Becker nevus. *Incorrect: Melanocytic nevus* While **melanocytic nevi** are hyperpigmented, they typically do not continue to **enlarge significantly** after childhood and generally do not develop new onset **hypertrichosis** as a primary feature. The size (15 mm) and progressive growth combined with hair development are more characteristic of a Becker nevus than a common melanocytic nevus. *Incorrect: Sebaceous nevus* **Sebaceous nevi** are typically **yellow-orange to tan, waxy plaques**, often on the scalp or face, with a cobblestone or papillomatous texture. They are not primarily characterized by **hyperpigmentation** and terminal hair growth, but rather by sebaceous gland proliferation. *Incorrect: Comedo nevus* A **comedo nevus** presents as a linear or unilateral group of **dilated follicular openings** filled with keratinous material, resembling blackheads. It is not characterized by diffuse **hyperpigmentation** or the increased terminal hair growth described in this case.

Q: Which of the following causes non-cicatricial alopecia?

All of the options. ***All of the options*** - **Tinea capitis**, **SLE** (Systemic Lupus Erythematosus), and **Alopecia areata** all can cause **non-cicatricial alopecia**. - **Non-cicatricial alopecia** refers to hair loss where the hair follicle is not permanently destroyed, and hair regrowth is possible, leaving no scarring. *Tinea capitis* - This is a **fungal infection** of the scalp that causes hair shafts to break, leading to patches of hair loss. - While it can lead to inflammation, it typically does not cause permanent destruction of the hair follicle unless severe and untreated, thus being predominantly **non-cicatricial**. *SLE* - Hair loss in **SLE** can occur due to various mechanisms, including diffuse thinning, patchy alopecia, or the characteristic "**lupus hair**" (fragile hairs around the hairline). - This type of hair loss is usually **non-scarring** and reversible, although discoid lupus erythematosus often causes scarring alopecia. *Alopecia areata* - This is an **autoimmune condition** characterized by patchy, sudden hair loss on the scalp or other body parts. - The hair follicles are attacked by the immune system but are not destroyed, making the condition largely **non-cicatricial** and potentially reversible.

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.

Q: In which condition is an ulceronecrotic nodule typically observed?

Lucio's leprosy. ***Lucio's leprosy*** - This is a rare, diffuse variant of **lepromatous leprosy** characterized by widespread, diffuse infiltration of the skin without distinct nodules. - The distinctive feature is the occurrence of **necrotizing vasculitis**, leading to painful, irregular ulcers and scars, known as **Lucio phenomenon** or erythema necroticans. *Lepromatous leprosy* - Characterized by **multiple, symmetrical nodules**, plaques, and diffuse infiltration, but typically without the profound ulceronecrotic changes seen in Lucio's leprosy. - The immune response is weak, leading to high bacterial load and widespread involvement, but usually not spontaneous ulceration. *Indeterminate leprosy* - This is an **early, undifferentiated form** of leprosy, characterized by a single or a few hypopigmented or erythematous macules. - Distinct nodules or ulceronecrotic lesions are not a feature of indeterminate leprosy, as the disease has not yet progressed to develop specific clinical manifestations. *Histoid leprosy* - A rare variant of lepromatous leprosy that presents with **cutaneous nodules** and papules that often resemble dermatofibromas or xanthomas. - These nodules are firm, smooth, and have a unique histological appearance, but they do not typically undergo spontaneous ulceronecrotic changes like those in Lucio's leprosy.

Q: Which of the following drugs is effective in the treatment of pityriasis versicolor?

Ketoconazole. ***Ketoconazole*** - **Ketoconazole** is an **azoles antifungal agent** effective against the *Malassezia* species, the causative agent of **pityriasis versicolor**. - It works by inhibiting the synthesis of **ergosterol**, a crucial component of the fungal cell membrane, leading to its disruption and fungal cell death. *Metronidazole* - **Metronidazole** is an **antibiotic** and **amoebicide** primarily used to treat bacterial and parasitic infections. - It has **no antifungal activity** and is thus ineffective against *Malassezia* or other fungal infections. *Griseofulvin* - **Griseofulvin** is an **oral antifungal drug** primarily used for **dermatophyte infections** of the skin, hair, and nails (e.g., tinea capitis, onychomycosis). - It is **ineffective against yeasts and molds**, including *Malassezia*, making it unsuitable for pityriasis versicolor. *Chloroquine* - **Chloroquine** is an **antimalarial drug** also used in the treatment of some autoimmune conditions like lupus erythematosus. - It possesses **no antifungal properties** and is not used to treat fungal infections of any kind.

Q: Skin scraping and KOH mounting is primarily used to diagnose which of the following conditions?

Dermatophyte infection. ***Dermatophyte infection*** - Skin scraping followed by **KOH mounting** is the **primary and gold standard** diagnostic method for dermatophyte infections - **Potassium hydroxide (KOH)** dissolves keratin, making **fungal hyphae and arthroconidia** clearly visible under microscopy - This is the **most common indication** for KOH preparation in dermatology practice - Demonstrates **septate hyphae** characteristic of dermatophytes *Candidiasis* - KOH mounting can also identify *Candida* species by revealing **pseudohyphae and budding yeast cells** - While KOH can diagnose candidiasis, dermatophyte infections remain the **primary and most frequent indication** for this test in skin lesions - Candida more commonly affects mucosal surfaces where other diagnostic methods may be preferred *Bacterial infection* - Bacterial infections are diagnosed using **Gram stain, culture, and sensitivity** testing - KOH mounting is specifically for **fungal elements** and does not visualize bacteria effectively - Bacterial skin infections require different diagnostic approaches *Herpes Simplex Virus (HSV)* - HSV infections are diagnosed using **Tzanck smear** (showing multinucleated giant cells), **viral culture, or PCR** - KOH mounting is exclusively for fungal identification and **cannot detect viruses** - Viral cytopathic effects are not visible with KOH preparation

Q: Pathergy test is used for which condition?

Behçet's syndrome. ***Behçet's syndrome*** - The **pathergy test** is a diagnostic test where a sterile needle is used to prick the skin, and a positive result (erythematous papule or pustule) indicates a hyperreactivity of the skin, common in **Behçet's syndrome**. - This syndrome is a **vasculitis** characterized by recurrent oral and genital ulcers, ocular inflammation, and skin lesions, where pathergy is a characteristic feature. *Lichen planus* - This is an **inflammatory dermatosis** affecting the skin, hair, nails, and mucous membranes, characterized by "6 P's": **Pruritic, Purple, Polygonal, Planar, Papules, and Plaques**. - The pathergy test is **not used** in the diagnosis of lichen planus. *Atopic dermatitis* - Also known as **eczema**, it is a chronic, relapsing inflammatory skin condition characterized by dry, itchy skin and often associated with a personal or family history of allergies, asthma, or allergic rhinitis. - Diagnosis is primarily clinical, focusing on characteristic skin lesions and symptoms, and the **pathergy test is not applicable**. *Reiter's syndrome* - Now known as **reactive arthritis**, this condition is an autoimmune disorder that develops in response to an infection elsewhere in the body, typically genitourinary or gastrointestinal. - It classically presents with **arthritis, urethritis, and conjunctivitis** (Can't see, can't pee, can't climb a tree), and the **pathergy test is not used** for its diagnosis.

Question 1

What is the treatment for granuloma inguinale?

Accepted Answer

Azithromycin

Answer

Tetracycline

Answer

Clarithromycin

Answer

Streptomycin

Question 2

Which type of leprosy does not involve nerve damage?

Accepted Answer

Indeterminate leprosy

Answer

Borderline tuberculoid leprosy

Answer

Tuberculoid leprosy

Answer

Lepromatous leprosy

Question 3

A 15cm hyperpigmented macule on an adolescent male undergoes changes such as coarseness, growth of hair & acne. Diagnosis is?

Accepted Answer

Becker nevus

Answer

Melanocytic nevus

Answer

Sebaceous nevus

Answer

Sebaceous adenoma

Question 4

What is the most likely diagnosis for a 15 mm hyperpigmented lesion on the shoulder that is enlarging and has hair growing from it?

Accepted Answer

Becker nevus

Answer

Melanocytic nevus

Answer

Sebaceous nevus

Answer

Comedo nevus

Question 5

Which of the following causes non-cicatricial alopecia?

Accepted Answer

All of the options

Answer

Tinea capitis

Answer

SLE

Answer

Alopecia areata

Question 6

Which of the following conditions does NOT cause nail pitting?

Accepted Answer

Pityriasis Rosea

Answer

Lichen planus

Answer

Fungal infection

Answer

Psoriasis

Question 7

In which condition is an ulceronecrotic nodule typically observed?

Accepted Answer

Lucio's leprosy

Answer

Lepromatous leprosy

Answer

Indeterminate leprosy

Answer

Histoid leprosy

Question 8

Which of the following drugs is effective in the treatment of pityriasis versicolor?

Accepted Answer

Ketoconazole

Answer

Metronidazole

Answer

Griseofulvin

Answer

Chloroquine

Question 9

Skin scraping and KOH mounting is primarily used to diagnose which of the following conditions?

Accepted Answer

Dermatophyte infection

Answer

Bacterial infection

Answer

Candidiasis

Answer

Herpes Simplex Virus (HSV)

Question 10

Pathergy test is used for which condition?

Accepted Answer

Behçet's syndrome

Answer

Lichen planus

Answer

Atopic dermatitis

Answer

Reiter's syndrome

NEET-PG 2013 — Dermatology