NEET-PG 2012 — Dermatology
19 Previous Year Questions with Answers & Explanations
Which of the following statements is true regarding donovanosis?
Raindrop pigmentation is caused by?
What is the best method to treat a large port-wine stain?
Which of the following pairs of conditions is incorrectly matched?
Muir–Torre syndrome shows
Richner-Hanhart syndrome is characterized by which of the following?
The appearance described as an inverted champagne bottle is associated with which condition?
Which of the following statements about spider telangiectasia is false?
Loss of intercellular cohesion between keratinocytes is referred to as?
Which of the following is NOT a feature of atopic dermatitis?
NEET-PG 2012 - Dermatology NEET-PG Practice Questions and MCQs
Question 1: Which of the following statements is true regarding donovanosis?
- A. Pseudolymphadenopathy is characteristic
- B. Penicillin is used for treatment
- C. Painful ulcer is characteristic
- D. Painless ulcerative lesions are characteristic of donovanosis (Correct Answer)
Explanation: ***Painless ulcerative lesions are characteristic of donovanosis*** - Donovanosis, also known as granuloma inguinale, is characterized by **painless, progressive ulcerative lesions** that can bleed easily. - The lesions typically start as papules or nodules and then erode to form **granulomatous ulcers** with a beefy red appearance. - This is a key distinguishing feature from chancroid (painful ulcers) and primary syphilis. *Pseudolymphadenopathy is characteristic* - While donovanosis can lead to swelling in the inguinal region, it's typically **pseudobuboes** (subcutaneous granulomas) rather than true lymphadenopathy. - However, this is not a defining characteristic, as pseudobuboes are less common and occur in advanced cases. - The primary feature remains the **painless ulcerative lesions**. *Penicillin is used for treatment* - **Penicillin** is not the standard treatment for donovanosis; it is ineffective against *Klebsiella granulomatis*. - The recommended treatment involves **macrolides** (e.g., azithromycin) or **tetracyclines** (e.g., doxycycline) for at least 3 weeks or until lesions heal. - Alternative regimens include **cotrimoxazole** or **fluoroquinolones**. *Painful ulcer is characteristic* - Donovanosis ulcers are typically **painless**, which distinguishes them from other genital ulcers like those seen in herpes or chancroid. - The **lack of pain** often contributes to delayed presentation and progression of the disease.
Question 2: Raindrop pigmentation is caused by?
- A. Dapsone
- B. Minocycline
- C. Clofazimine
- D. Arsenic (Correct Answer)
Explanation: ***Arsenic*** - Chronic **arsenic** exposure can lead to characteristic skin manifestations, including **raindrop pigmentation**, which appears as small, scattered hypopigmented macules surrounded by hyperpigmented skin, particularly on the trunk and extremities. - This pigmentation is a result of altered **melanin distribution** and **keratinocyte damage** due to arsenic toxicity. *Clofazimine* - **Clofazimine** is an anti-leprosy drug that can cause **reddish-brown to bluish-black skin discoloration**, which is a diffuse pigmentation, not "raindrop" in nature. - The pigmentation associated with clofazimine is due to drug deposition in tissues and is usually reversible. *Dapsone* - **Dapsone** is primarily known for causing **methemoglobinemia** and **hemolytic anemia**, especially in patients with G6PD deficiency. - While it can cause some dermatological side effects, **pigmentation** is not a characteristic feature, and it does not produce a "raindrop" pattern. *Minocycline* - **Minocycline** can cause various types of pigmentation, including **blue-gray discoloration** in scars, shins, and mucous membranes, as well as diffuse brown pigmentation. - However, the pigmentation caused by minocycline is typically diffuse or localized to specific areas, and it does not present as "raindrop pigmentation."
Question 3: What is the best method to treat a large port-wine stain?
- A. Radiotherapy
- B. Excision with skin grafting
- C. Pulsed dye laser (Correct Answer)
- D. Tattooing
Explanation: ***Pulsed dye laser*** - The **pulsed dye laser (PDL)** is considered the **gold standard** for treating port-wine stains due to its specific targeting of hemoglobin in the dilated capillaries without damaging surrounding tissue. - This treatment involves multiple sessions to progressively lighten the stain and prevent complications such as **nodularity** and **tissue hypertrophy**. *Radiotherapy* - **Radiotherapy** is generally not recommended for port-wine stains due to its potential for **scarring**, **pigment changes**, and risk of **malignancy**. - It is an aggressive treatment typically reserved for **cancerous conditions** or severe proliferative vascular lesions not amenable to other treatments. *Tattooing* - **Tattooing** involves injecting skin-colored pigments into the lesion to camouflage it, but it does not treat the underlying vascular abnormality. - This method can result in an **artificial appearance**, **uneven coverage**, and potential for **allergic reactions** or infections. *Excision with skin grafting* - **Surgical excision** of a large port-wine stain would result in a **significant scar** and require **skin grafting**, which carries risks of graft failure, poor aesthetic outcome, and color mismatch. - This method is generally reserved for very small, localized lesions or those with significant **nodular hypertrophy** that cannot be effectively managed by laser therapy.
Question 4: Which of the following pairs of conditions is incorrectly matched?
- A. Erythema gyratum repens - malignancy
- B. Erythema marginatum - rheumatic fever
- C. Necrotic acral erythema - HCV
- D. Erythema chronicum migrans - malignancy (Correct Answer)
Explanation: ***Erythema chronicum migrans - malignancy*** - **Erythema chronicum migrans** is the characteristic skin lesion of **Lyme disease**, caused by the bacterium *Borrelia burgdorferi*, transmitted by ticks. - It is not associated with malignancy; rather, its presence indicates a **bacterial infection** requiring antibiotic treatment. *Erythema marginatum - rheumatic fever* - **Erythema marginatum** is a **major diagnostic criterion** for **rheumatic fever**, a post-streptococcal inflammatory disease. - The rash is characterized by non-itchy, pink or red macules with raised, serpiginous borders that spread outwards, often transient. *Erythema gyratum repens - malignancy* - **Erythema gyratum repens** is a rare **paraneoplastic dermatosis** strongly associated with various internal malignancies, most commonly lung cancer. - It presents as a characteristic **wood-grain-like pattern** of concentric, migratory erythematous bands. *Necrotic acral erythema - HCV* - **Necrotic acral erythema** is a skin condition that predominantly affects the hands and feet and has a strong association with **hepatitis C virus (HCV) infection**. - It presents with violaceous plaques that can ulcerate and become necrotic, often in patients with chronic HCV.
Question 5: Muir–Torre syndrome shows
- A. Sebaceous gland tumors (Correct Answer)
- B. Intestinal polyps
- C. Lisch nodules
- D. Hyperelastic joints
Explanation: ***Sebaceous gland tumors*** - **Muir-Torre syndrome** is a genetic condition characterized by the presence of at least one **sebaceous gland tumor** (adenoma, epithelioma, or carcinoma) and at least one internal malignancy. - It is considered a variant of **Lynch syndrome (hereditary nonpolyposis colorectal cancer - HNPCC)**, stemming from germline mutations in **DNA mismatch repair genes**. *Intestinal polyps (associated with familial adenomatous polyposis)* - While Lynch syndrome (to which Muir-Torre is related) does involve an increased risk of colorectal cancer, **multiple intestinal polyps** are the hallmark of **Familial Adenomatous Polyposis (FAP)**. - FAP is caused by a mutation in the **APC gene**, distinct from the mismatch repair gene mutations seen in Muir-Torre syndrome. *Lisch nodules (associated with Neurofibromatosis type 1)* - **Lisch nodules** are benign **iris hamartomas** typically found in patients with **Neurofibromatosis type 1 (NF1)**. - NF1 is a neurocutaneous disorder caused by a mutation in the **NF1 gene**, presenting with café-au-lait spots, neurofibromas, and optic gliomas, which are unrelated to Muir-Torre syndrome. *Hyperelastic joints (associated with Ehlers-Danlos syndrome)* - **Hyperelasticity of joints** and skin is a characteristic feature of **Ehlers-Danlos syndrome (EDS)**, a group of heritable disorders affecting connective tissue. - EDS is caused by defects in **collagen synthesis or processing**, and its clinical manifestations are distinct from the mucocutaneous and internal malignancies seen in Muir-Torre syndrome.
Question 6: Richner-Hanhart syndrome is characterized by which of the following?
- A. Autosomal dominant
- B. Associated with abnormality in lipid metabolism
- C. Ocular and cutaneous features (Correct Answer)
- D. Never associated with neurological involvement
Explanation: ***Ocular and cutaneous features*** - **Richner-Hanhart syndrome**, also known as **Tyrosinemia type II**, is characterized by the classic triad of **painful hyperkeratotic plaques** on the palms and soles (cutaneous features), **corneal ulcers** or **dendritic keratitis** (ocular features), and **variable neurological involvement**. - These features arise from the accumulation of **tyrosine** due to a deficiency of the enzyme **hepatic tyrosine aminotransferase (TAT)**. - The **ocular and cutaneous manifestations** are the hallmark features that define this syndrome. *Autosomal dominant* - Richner-Hanhart syndrome is inherited in an **autosomal recessive** pattern, meaning two copies of the defective gene (TAT gene on chromosome 16) are required for the condition to manifest. - An **autosomal dominant** inheritance pattern would mean only one copy of the defective gene is sufficient to cause the disorder. *Associated with abnormality in lipid metabolism* - The syndrome is an inborn error of **amino acid metabolism**, specifically involving **tyrosine**, not lipid metabolism. - Diseases associated with abnormality in **lipid metabolism** include conditions like Gaucher disease, Niemann-Pick disease, or Fabry disease. *Never associated with neurological involvement* - This is **incorrect**. **Neurological involvement** including intellectual disability, developmental delay, seizures, and behavioral problems occurs in **30-50% of cases**. - The accumulation of **tyrosine** and its metabolites (particularly tyrosine crystals) can be **neurotoxic**, leading to varying degrees of neurological impairment. - Early dietary restriction of tyrosine and phenylalanine can prevent or minimize neurological complications.
Question 7: The appearance described as an inverted champagne bottle is associated with which condition?
- A. Varicose veins
- B. Deep vein thrombosis
- C. Venous ulceration
- D. Lipodermatosclerosis (Correct Answer)
Explanation: ***Lipodermatosclerosis*** - This condition presents with a characteristic "inverted champagne bottle" appearance, where the **ankle area is narrow** and the **calf area above it is wider** due to fibrotic changes and fat atrophy. - It's a severe manifestation of **chronic venous insufficiency**, characterized by **skin hardening**, pigmentation, and inflammation, often preceding venous ulceration. *Varicose veins (enlarged, twisted veins)* - While associated with **venous insufficiency**, varicose veins themselves are **dilated, tortuous superficial veins**, and do not typically cause the generalized lower leg shape change described. - They may cause swelling and discomfort but do not directly lead to the **fibrotic narrowing** seen in an "inverted champagne bottle" leg. *Deep vein thrombosis (DVT) (acute venous obstruction)* - DVT is an **acute condition** involving a **blood clot in a deep vein**, leading to sudden onset pain, swelling, and redness. - It does not cause the **chronic skin changes** and **fibrotic reshaping** of the calf and ankle that characterize lipodermatosclerosis. *Venous ulceration (open sores due to venous insufficiency)* - Venous ulcers are **open sores** that occur in severe chronic venous insufficiency, often found above the medial malleolus. - While they are a complication of the underlying venous disease that can also cause lipodermatosclerosis, the ulceration itself is a **skin lesion**, not the **overall inverted champagne bottle shape** of the leg.
Question 8: Which of the following statements about spider telangiectasia is false?
- A. More common in males (Correct Answer)
- B. Light therapy for treatment
- C. May be associated with liver disease
- D. Can be caused by trauma
Explanation: ***More common in males*** - This statement is **FALSE** because spider telangiectasias (spider nevi/spider angiomas) are more commonly observed in **females**, often due to hormonal influences like **estrogen**. - They are frequently associated with conditions such as **pregnancy**, **oral contraceptive use**, or **chronic liver disease**, highlighting a female predominance. - The estrogen-dependent nature explains their higher prevalence in women of reproductive age. *Can be caused by trauma* - This statement is **TRUE** in a broader sense, though classical spider telangiectasias are primarily hormonally-mediated rather than traumatic. - While **simple telangiectasias** can develop after localized trauma or repeated pressure, spider telangiectasias have a characteristic morphology (central arteriole with radiating vessels) and are typically associated with **estrogen excess** or **liver disease**. - For exam purposes, this is considered a true statement as telangiectatic vessels can be influenced by local factors. *Light therapy for treatment* - This statement is **TRUE**. **Laser therapy**, specifically **pulsed dye laser (PDL)** or **intense pulsed light (IPL)**, is the most effective treatment for spider telangiectasias. - The laser selectively targets **hemoglobin** in the dilated vessels, causing photocoagulation and vessel obliteration, leading to excellent cosmetic results. *May be associated with liver disease* - This statement is **TRUE**. Spider telangiectasias are a well-recognized cutaneous manifestation of **chronic liver disease**, especially **cirrhosis**. - Impaired hepatic function leads to decreased **estrogen metabolism** (hyperestrogenemia), contributing to the development of these vascular lesions. - They are one of the stigmata of chronic liver disease, along with palmar erythema and gynecomastia.
Question 9: Loss of intercellular cohesion between keratinocytes is referred to as?
- A. Acanthosis
- B. Acantholysis (Correct Answer)
- C. Keratinolysis
- D. Spongiosis
Explanation: ***Acantholysis*** - This term specifically refers to the **loss of cohesion between keratinocytes** in the epidermis due to the breakdown of desmosomal attachments. - It is a hallmark feature of several **blistering skin diseases**, such as pemphigus. *Acanthosis* - This refers to the **thickening of the stratum spinosum** (prickle cell layer) of the epidermis, often due to an increase in the number of keratinocytes. - It is seen in conditions like **psoriasis** and seborrheic keratosis, but does not involve a loss of intercellular cohesion. *Keratinolysis* - This term describes the **breakdown or dissolution of keratin**, which is the primary structural protein of the epidermis. - While keratinocytes produce keratin, keratinolysis itself is not the specific term for loss of cohesion between these cells. *Spongiosis* - This is defined as **intercellular edema** (fluid accumulation) within the epidermis, especially prominent in the stratum spinosum. - It leads to the widening of intercellular spaces and stretching of desmosomes, but the cells generally remain attached, unlike in acantholysis.
Question 10: Which of the following is NOT a feature of atopic dermatitis?
- A. Dennie-Morgan fold
- B. Darier’s Sign (Correct Answer)
- C. Hyperlinearity of palms
- D. Hertoghe’s sign
Explanation: ***Darier's Sign*** - **Darier's sign** is characteristic of **urticaria pigmentosa** (cutaneous mastocytosis), where rubbing a skin lesion causes the formation of an urticarial wheal due to mast cell degranulation - It is **not associated** with the pathogenesis or clinical presentation of **atopic dermatitis** *Dennie-Morgan fold* - **Dennie-Morgan folds** are extra folds or lines in the skin just below the lower eyelids - They are a common clinical sign observed in patients with **atopic dermatitis**, often linked to chronic inflammation and allergic reactions affecting the skin around the eyes *Hertoghe's sign* - **Hertoghe's sign** refers to the thinning or absence of the lateral third of the eyebrows - This sign is often seen in individuals with **atopic dermatitis**, as well as in other conditions like hypothyroidism *Hyperlinearity of palms* - **Hyperlinearity of palms** refers to the exaggerated creases and lines on the palms of the hands - This is a common **stigmata of atopy** and is frequently observed in patients with **atopic dermatitis**, reflecting the underlying predisposition to skin dryness and altered epidermal barrier function