NEET-PG 2019 - Dermatology Practice Questions

Q: Which is not correct about the lesion shown below?

Bilaterally symmetrical dermatomal vesicular eruption. ***Bilaterally symmetrical dermatomal vesicular eruption*** - The image shows a **unilateral, dermatomal vesicular eruption**, characteristic of herpes zoster (shingles). - Herpes zoster lesions are typically restricted to **one side of the body** and follow a single dermatome, making bilateral symmetry incorrect. *The lesions are infectious to seronegative individuals* - The vesicles of herpes zoster contain **live varicella-zoster virus (VZV)**, which can be transmitted through direct contact. - Individuals who have not previously had chickenpox (seronegative for VZV) can contract **chickenpox** (not shingles) from exposure to these lesions. *Can be associated with meningoencephalitis* - Although rare, disseminated herpes zoster can lead to severe complications, including **meningoencephalitis** if the virus spreads to the central nervous system. - This complication is more likely in **immunocompromised individuals**. *Geniculate ganglion is involved in Ramsay hunt syndrome* - **Ramsay Hunt syndrome (Herpes zoster oticus)** is a specific complication of VZV reactivation involving the **geniculate ganglion** of the facial nerve. - This involvement leads to facial nerve palsy, ear pain, and typical vesicular rash in the ear canal or on the auricle.

Q: A one-year-old child presents with the following lesion on the face. His mother has a history of bronchial asthma. What is the diagnosis?

Atopic dermatitis. ***Atopic dermatitis*** - The rash on the face of a one-year-old, coupled with a maternal history of **bronchial asthma**, strongly suggests **atopic dermatitis (eczema)** due to its association with the **atopic triad** (eczema, asthma, allergic rhinitis). - In infants, atopic dermatitis commonly presents as erythematous, scaly, and sometimes **weeping patches** on the face and extensor surfaces. *Eczematous dermatitis* - While atopic dermatitis is a form of eczematous dermatitis, this term is **too broad** and does not specify the underlying cause evident from the patient's history. - Eczematous dermatitis describes a **pattern of inflammation** rather than a specific diagnosis. *Seborrheic dermatitis* - Typically characterized by **greasy, yellowish scales** on an erythematous base, often affecting the scalp (**cradle cap**), eyebrows, and nasolabial folds. - It usually **lacks the strong association with atopy** seen in this case. *Contact dermatitis* - Caused by exposure to an **irritant or allergen**, leading to a localized rash. - The diffuse nature of the rash in the image and the family history of asthma make a specific contact allergen less likely as the primary cause.

Q: A patient presents with the skin finding shown in the image. Identify the most likely diagnosis for this lesion.

Piebaldism. ***Piebaldism*** - The image shows a **localized patch of depigmentation** on the forehead, characteristic of **piebaldism**. - **Piebaldism** is a rare, congenital autosomal dominant disorder caused by a defect in melanocyte development and migration, resulting in stable, well-demarcated depigmented areas, often with a **white forelock**. *Vitiligo* - **Vitiligo** typically presents as **progressive, acquired macules and patches of depigmentation** that often enlarge over time. - While it can appear on the face, the sharply demarcated, congenital appearance seen here is more consistent with piebaldism. *Contact leukoderma* - **Contact leukoderma** is an **acquired depigmentation** resulting from exposure to chemicals (e.g., rubber, phenols). - It would usually present in areas of direct contact, and the congenital nature of the lesion in the image rules this out. *Albinism* - **Albinism** is a **generalized hypopigmentation** affecting the skin, hair, and eyes due to a defect in melanin production. - The image shows a localized patch of depigmentation, not a widespread lack of pigment characteristic of albinism.

Q: A child presents with the following lesion in the neck folds. The gram stain from the lesion is shown below. Comment on the diagnosis.

Erythrasma. **Erythrasma** - The image shows a **reddish-brown, finely wrinkled lesion** in an intertriginous area (neck folds), consistent with erythrasma. - The gram stain reveals **long, filamentous Gram-positive bacilli**, characteristic of *Corynebacterium minutissimum*, the causative agent of erythrasma. *Impetigo contagiosa* - This typically presents as **honey-colored crusted lesions** or vesicles, often caused by *Staphylococcus aureus* or *Streptococcus pyogenes*. - Gram stain would show **Gram-positive cocci** (clusters for staph, chains for strep), not filamentous bacilli. *Scrofuloderma* - This is a form of **cutaneous tuberculosis**, typically presenting as **nontender subcutaneous nodules** that eventually ulcerate and discharge caseous material. - Diagnosis is confirmed by identifying acid-fast bacilli or histology showing granulomas; the gram stain and lesion appearance are not consistent. *Scrum pox* - This is a **viral skin infection** (often herpes simplex virus) seen in wrestlers, presenting as **vesicular or ulcerative lesions**. - It would not show filamentous Gram-positive bacilli on a bacterial gram stain.

Q: What is the diagnosis of the lesion visible in neck folds of this child?

Intertriginous candida. ***Intertriginous candida*** - The image shows **erythema, scaling, and white satellite lesions** in a skin fold, which is characteristic of candidal intertrigo. - This condition thrives in **warm, moist environments** like neck folds of infants, often presenting with burning and itching. *SSSS* - **Staphylococcal Scalded Skin Syndrome (SSSS)** is characterized by widespread **erythema and superficial blistering**, leading to skin peeling, which is not seen here. - It usually involves a more diffuse rash and often has a **positive Nikolsky sign**, unlike the localized lesion shown. *Impetigo* - **Impetigo** typically presents with **honey-colored crusts** and is caused by bacterial infection, primarily *Staphylococcus aureus* or *Streptococcus pyogenes*. - While it can occur in skin folds, the characteristic white, cheesy appearance and satellite lesions seen in the image are not typical of impetigo. *Ecthyma* - **Ecthyma** is a more severe, ulcerative form of impetigo, characterized by **punched-out ulcers with adherent crusts** that extend into the dermis. - The lesion in the image does not show the deep ulceration or dense, dark crusts associated with ecthyma.

Q: In a patient with the following lesion on scalp, what changes are seen in the nails?

Pitting of nails. ***Pitting of nails*** - The image shows a patch of **alopecia areata** on the scalp. **Nail pitting** is the most common and characteristic nail change associated with alopecia areata, occurring in **10-66% of cases**. - Pitting appears as small depressions or **"ice-pick" marks** on the nail surface, resulting from defective nail matrix keratinization. - Other nail changes in alopecia areata include **trachyonychia (rough nails), red spotted lunulae, onycholysis**, and **Beau's lines**. *Dorsal pterygium of nails* - **Dorsal pterygium** occurs when the proximal nail fold fuses with and extends over the nail plate, creating a wing-like scar. - This is classically associated with **lichen planus, trauma, burns, vasculitis**, and **graft-versus-host disease** — **NOT alopecia areata**. - It can lead to permanent nail dystrophy or nail loss. *Azure nails* - **Azure nails** (blue nails) are typically associated with **Wilson's disease** (copper accumulation) or **minocycline use**, not alopecia areata. - They represent a blue-gray discoloration of the nail bed or lunula. *Yellow nail discolouration* - **Yellow nail syndrome** is a rare condition characterized by slow-growing, thickened, yellow nails, often associated with **lymphedema** and **respiratory problems** (pleural effusions, chronic bronchitis). - It is not linked to alopecia areata.

Question 1

Which is not correct about the lesion shown below?

Accepted Answer

Bilaterally symmetrical dermatomal vesicular eruption

Answer

The lesions are infectious to seronegative individuals

Answer

Can be associated with meningoencephalitis

Answer

Geniculate ganglion is involved in Ramsay hunt syndrome

Question 2

A one-year-old child presents with the following lesion on the face. His mother has a history of bronchial asthma. What is the diagnosis?

Accepted Answer

Atopic dermatitis

Answer

Eczematous dermatitis

Answer

Seborrheic dermatitis

Answer

Contact dermatitis

Question 3

A patient presents with the skin finding shown in the image. Identify the most likely diagnosis for this lesion.

Accepted Answer

Piebaldism

Answer

Vitiligo

Answer

Contact leukoderma

Answer

Albinism

Question 4

A child presents with the following lesion in the neck folds. The gram stain from the lesion is shown below. Comment on the diagnosis.

Accepted Answer

Erythrasma

Answer

Impetigo contagiosa

Answer

Scrofuloderma

Answer

Scrum pox

Question 5

What is the diagnosis of the lesion visible in neck folds of this child?

Accepted Answer

Intertriginous candida

Answer

SSSS

Answer

Impetigo

Answer

Ecthyma

Question 6

In a patient with the following lesion on scalp, what changes are seen in the nails?

Accepted Answer

Pitting of nails

Answer

Azure nails

Answer

Dorsal pterygium of nails

Answer

Yellow nail discolouration

NEET-PG 2019 — Dermatology