Dermatology
6 questionsWhich type of ultraviolet radiation causes the most skin disorders?
Schamberg's purpura is seen on?
What is the most likely diagnosis for a 15 mm hyperpigmented lesion on the shoulder that is enlarging and has hair growing from it?
A 15cm hyperpigmented macule on an adolescent male undergoes changes such as coarseness, growth of hair & acne. Diagnosis is?
What is the treatment for granuloma inguinale?
What percentage of skin involvement is characteristic of erythroderma?
NEET-PG 2013 - Dermatology NEET-PG Practice Questions and MCQs
Question 1291: Which type of ultraviolet radiation causes the most skin disorders?
- A. UV-A
- B. UV-B (Correct Answer)
- C. UV-C
- D. None of the options
Explanation: ***UV-B*** - **UV-B radiation** is a major cause of **sunburn** and directly damages DNA, leading to most **skin cancers** (basal cell carcinoma, squamous cell carcinoma, and melanoma). - It plays a significant role in photoaging and the development of most **skin disorders** related to sun exposure. *UV-A* - **UV-A radiation** penetrates deeper into the skin than UV-B and is primarily associated with **photoaging**, producing wrinkles and fine lines. - While it contributes to skin cancer development, its direct role in DNA damage and sunburn is less than that of UV-B. *UV-C* - **UV-C radiation** is the most damaging type of UV light, but it is almost entirely **absorbed by the Earth's ozone layer** and does not reach the Earth's surface. - Therefore, it does not typically cause skin disorders in humans under natural conditions. *None of the options* - This option is incorrect because **UV-B radiation** is well-established as a primary cause of numerous skin disorders, including most skin cancers and sunburn.
Question 1292: Schamberg's purpura is seen on?
- A. Face
- B. Feet (Correct Answer)
- C. Chest
- D. Arms
Explanation: ***Feet*** - Schamberg's purpura, also known as **progressive pigmented purpuric dermatosis**, most commonly affects the **lower extremities**, particularly the feet and ankles. - The characteristic reddish-brown patches with "cayenne pepper" spots are due to **capillary inflammation** and extravasation of red blood cells. *Face* - While purpura can occur on the face due to other conditions, Schamberg's purpura **rarely presents in this location**. - Facial lesions often suggest different underlying etiologies, such as **vasculitis** or trauma. *Chest* - The chest is an **uncommon site** for Schamberg's purpura. - Involvement of the trunk is less typical compared to the dependent areas of the legs. *Arms* - Although the arms can occasionally be affected, the **feet and lower legs are the predominant sites** for Schamberg's purpura due to factors like **gravity** and hydrostatic pressure. - When present on the arms, it might indicate a more widespread or atypical presentation.
Question 1293: What is the most likely diagnosis for a 15 mm hyperpigmented lesion on the shoulder that is enlarging and has hair growing from it?
- A. Melanocytic nevus
- B. Becker nevus (Correct Answer)
- C. Sebaceous nevus
- D. Comedo nevus
Explanation: ***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.
Question 1294: A 15cm hyperpigmented macule on an adolescent male undergoes changes such as coarseness, growth of hair & acne. Diagnosis is?
- A. Melanocytic nevus
- B. Becker nevus (Correct Answer)
- C. Sebaceous nevus
- D. Sebaceous adenoma
Explanation: ***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.
Question 1295: What is the treatment for granuloma inguinale?
- A. Tetracycline
- B. Azithromycin (Correct Answer)
- C. Clarithromycin
- D. Streptomycin
Explanation: ***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).
Question 1296: What percentage of skin involvement is characteristic of erythroderma?
- A. More than 90% (Correct Answer)
- B. Less than 30%
- C. 30% to 60%
- D. 60% to 70%
Explanation: ***More than 90%*** - Erythroderma, also known as **exfoliative dermatitis**, is defined by diffuse redness and scaling involving **more than 90% of the body surface area**. - This extensive involvement leads to significant physiological disturbances due to impaired skin barrier function. *Less than 30%* - Skin involvement less than 30% does not meet the criteria for erythroderma and would be considered more localized dermatological conditions. - This percentage of involvement would typically indicate a benign rash or localized eczema, not a widespread inflammatory process. *30% to 60%* - While significant, 30% to 60% skin involvement is still insufficient to classify a condition as erythroderma. - This range might be seen in severe but still localized forms of conditions like psoriasis or eczema. *60% to 70%* - 60% to 70% involvement is extensive but falls short of the critical threshold for erythroderma. - Although indicating widespread disease, it does not constitute the near-total body erythema and scaling characteristic of erythroderma.
Internal Medicine
2 questionsLovibond profile sign is seen in ?
Which of the following is not classified as a cutaneous porphyria?
NEET-PG 2013 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 1291: Lovibond profile sign is seen in ?
- A. Koilonychia (spoon nails)
- B. Platynochia (flat nails)
- C. Nail clubbing (Correct Answer)
- D. Onycholysis (separation of the nail from the nail bed)
Explanation: Nail clubbing - The Lovibond profile sign (Lovibond's angle or profile sign) is a clinical finding where the angle between the nail plate and the proximal nail fold straightens or becomes greater than 180 degrees. - This sign is a key indicator of nail clubbing, which is often associated with underlying systemic conditions such as respiratory or cardiac diseases [1]. Koilonychia (spoon nails) - Koilonychia presents as concave or spoon-shaped nails, where the nail plate is depressed centrally with everted edges [1]. - This condition is typically associated with iron deficiency anemia and does not involve an alteration of the Lovibond angle. Platynochia (flat nails) - Platynochia refers to nails that are unusually flat without the normal convex curvature. - This is a descriptive term for nail shape and is not specifically evaluated by the Lovibond profile sign. Onycholysis (separation of the nail from the nail bed) - Onycholysis is the detachment of the nail plate from the nail bed, usually starting at the distal free edge. - This condition is unrelated to the angle of the nail and the nail fold, which are assessed by the Lovibond profile sign.
Question 1292: Which of the following is not classified as a cutaneous porphyria?
- A. Congenital erythropoietic porphyria
- B. Erythropoietic protoporphyria
- C. Sideroblastic anemia (Correct Answer)
- D. Hereditary coproporphyria
Explanation: ***Hereditary coproporphyria*** - This condition is primarily associated with **acute episodes** and **neuropathy**, rather than cutaneous manifestations. [2] - Unlike cutaneous porphyrias, symptoms are more systemic and do not commonly present with **skin lesions**. Although skin features can occur in some instances, they mimic porphyria cutanea tarda. [2] *Congenital erythropoeitic porphyria* - Characterized by severe **cutaneous symptoms** such as blistering and photosensitivity due to **skin exposure**. - Patients exhibit notable **facial disfigurement** and can have **hemolytic anemia**, aligning it clearly with the cutaneous forms of porphyria. *Sideroblastic anemia* - This condition involves issues with **hemoglobin synthesis** and does not fit the porphyria classification. [1] - It primarily presents with **microcytic anemia**, and the symptoms are primarily hematological, not cutaneous. [1] *Erythropoeitic porphyria* - Characterized by **severe photosensitivity** and skin manifestations, similar to congenital erythropoeitic porphyria. [1] - Patients may develop **blisters** and **hyperpigmentation** upon sun exposure, categorizing it among cutaneous porphyrias. [2]
Pharmacology
2 questionsWhich drug is most commonly associated with causing exanthema?
Which drug is most commonly associated with causing fixed drug eruptions?
NEET-PG 2013 - Pharmacology NEET-PG Practice Questions and MCQs
Question 1291: Which drug is most commonly associated with causing exanthema?
- A. Atropine
- B. Phenytoin
- C. Sulfonamide (Correct Answer)
- D. All of the options
Explanation: ***Sulfonamide*** - **Sulfonamides** are among the **most common causes** of drug-induced exanthema (maculopapular/morbilliform rash). - They account for a significant proportion of cutaneous adverse drug reactions, with exanthema being the most frequent presentation. - The mechanism typically involves a **delayed hypersensitivity reaction** (Type IV) to the drug or its metabolites. - **Classic presentation:** Symmetrical, erythematous, maculopapular rash appearing 7-14 days after drug initiation. *Phenytoin* - **Phenytoin** can cause exanthematous eruptions, but it is more notably associated with **severe cutaneous adverse reactions** such as: - **DRESS syndrome** (Drug Reaction with Eosinophilia and Systemic Symptoms) - **Stevens-Johnson syndrome (SJS)** and **Toxic Epidermal Necrolysis (TEN)** - While exanthema can occur, **sulfonamides** are more frequently implicated in simple morbilliform rashes. *Atropine* - **Atropine** is an anticholinergic agent primarily causing **predictable pharmacological effects**: - Dry mouth, mydriasis, tachycardia, urinary retention - **Allergic skin reactions** with atropine are rare and not a characteristic adverse effect. - Atropine is **not recognized** as a common cause of exanthema. *All of the options* - This is incorrect because **atropine** is not commonly associated with exanthema. - While both sulfonamides and phenytoin can cause exanthema, only **sulfonamides** are considered among the **most common** causes.
Question 1292: Which drug is most commonly associated with causing fixed drug eruptions?
- A. Aminoglycoside
- B. Sulfonamide (Correct Answer)
- C. Erythromycin
- D. None of the options
Explanation: ***Sulfonamide*** - **Sulfonamides**, particularly **sulfamethoxazole-trimethoprim**, are frequently implicated in causing fixed drug eruptions. - A fixed drug eruption characteristically recurs at the **same cutaneous site** each time the offending drug is administered. *Aminoglycoside* - **Aminoglycosides** are broad-spectrum antibiotics known for potential **ototoxicity** and **nephrotoxicity**. - While they can cause various adverse reactions, fixed drug eruptions are **not a common association** with this drug class. *Erythromycin* - **Erythromycin** is a macrolide antibiotic primarily associated with **gastrointestinal side effects**, such as nausea and abdominal cramping. - Although drug eruptions can occur, fixed drug eruptions are **not typically linked** to erythromycin. *None of the options* - This option is incorrect because **sulfonamides** are well-documented causes of fixed drug eruptions. - Therefore, there is a specific drug class listed that is strongly associated with this condition.