Dermatology
7 questionsNikolsky's sign is associated with which of the following conditions?
What is the treatment for granuloma inguinale?
What is the treatment of choice for lichen planus?
The Grattage test is used to diagnose which of the following conditions?
Most common metal in contact allergic dermatitis is?
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?
Which of the following conditions does NOT cause nail pitting?
NEET-PG 2013 - Dermatology NEET-PG Practice Questions and MCQs
Question 1381: Nikolsky's sign is associated with which of the following conditions?
- A. Herpes zoster
- B. Bullous impetigo
- C. All of the options
- D. Pemphigus (Correct Answer)
Explanation: ***Pemphigus*** - **Nikolsky's sign** is the **most characteristic and consistent** clinical finding in pemphigus, where slight lateral pressure on seemingly normal skin near a blister or erosion causes the epidermis to shear off, forming a new blister or denudation. - This sign indicates **intraepidermal blistering** due to the loss of cell adhesion (acantholysis) caused by autoantibodies against desmoglein proteins. - **Pemphigus is the classic condition** associated with a positive Nikolsky's sign in medical literature and examinations. *Herpes zoster* - **Herpes zoster** (shingles) is characterized by painful, vesicular eruptions in a **dermatomal distribution**, which do **not exhibit Nikolsky's sign**. - The vesicles in herpes zoster are **intraepidermal** but result from viral cytopathic effect, not acantholysis, and the roof of the vesicle remains intact with lateral pressure. *Bullous impetigo* - Bullous impetigo is a superficial skin infection caused by *Staphylococcus aureus* that produces **large, flaccid blisters**. - While **Nikolsky's sign can occasionally be positive** in bullous impetigo (particularly in staphylococcal scalded skin syndrome), it is **much less consistent and prominent** compared to pemphigus. - The key distinction is that pemphigus remains the **most characteristic association** with Nikolsky's sign in clinical practice and examinations. *All of the options* - This option is incorrect because Nikolsky's sign is **most specifically and consistently associated with pemphigus**. - While bullous impetigo may occasionally show Nikolsky's sign, **pemphigus is the classic answer** for this clinical finding in medical examinations.
Question 1382: 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 1383: What is the treatment of choice for lichen planus?
- A. Topical corticosteroids (Correct Answer)
- B. Systemic corticosteroids
- C. Antihistamines
- D. Acitretin
Explanation: ***Topical corticosteroids*** - **Topical corticosteroids** are the first-line treatment for localized lichen planus due to their potent **anti-inflammatory** and **immunosuppressive** effects. - They effectively reduce **itching**, **inflammation**, and the characteristic **violaceous papules** of lichen planus. *Systemic corticosteroids* - **Systemic corticosteroids** are typically reserved for widespread, severe, or refractory cases of lichen planus, not as initial treatment. - Their use is limited by potential **systemic side effects**, such as **osteoporosis**, **hypertension**, and **diabetes**. *Antihistamines* - **Antihistamines** primarily target **itching** (pruritus) associated with lichen planus but do not address the underlying **inflammatory process** or resolve the skin lesions themselves. - They may be used as an adjunct for symptomatic relief, especially for nocturnal pruritus. *Acitretin* - **Acitretin** is a **retinoid** used for severe or refractory cases of lichen planus (including erosive, oral, and hypertrophic variants), but not as first-line treatment for localized cutaneous disease. - It carries significant **teratogenic risks** and other side effects, making it unsuitable as initial therapy when topical corticosteroids are effective.
Question 1384: The Grattage test is used to diagnose which of the following conditions?
- A. Tinea capitis
- B. Lichen planus
- C. Pemphigus vulgaris
- D. Psoriasis (Correct Answer)
Explanation: ***Psoriasis*** - The **Grattage test** (candle grease sign) involves **scraping the psoriatic lesion** to reveal characteristic features - First reveals **fine, silvery-white scales** resembling candle wax - Further scraping exposes **pinpoint bleeding points** (**Auspitz sign**) due to exposure of dilated capillaries in dermal papillae - This combination is **pathognomonic for psoriasis** and helps differentiate it from other scaly dermatoses *Tinea capitis* - A **fungal infection of the scalp** caused by dermatophytes - Diagnosed by **KOH mount** (showing fungal hyphae), **fungal culture**, and sometimes **Wood's lamp examination** - The Grattage test is not used for diagnosing fungal infections *Lichen planus* - Characterized by **purplish, polygonal, flat-topped, pruritic papules and plaques** - Surface shows **Wickham's striae** (fine white lines) - Diagnosis is **clinical**, supported by **skin biopsy** showing band-like lymphocytic infiltrate and sawtooth rete ridges - The Grattage test is not applicable *Pemphigus vulgaris* - A severe **autoimmune blistering disorder** with **suprabasal acantholysis** - Presents with **flaccid bullae** that rupture easily, leaving erosions - Diagnosed by **skin biopsy**, **direct immunofluorescence** (intercellular IgG and C3 deposits), and **Nikolsky's sign** (positive) - The Grattage test is not used for bullous disorders
Question 1385: Most common metal in contact allergic dermatitis is?
- A. Gold
- B. Silver
- C. Aluminum
- D. Nickel (Correct Answer)
Explanation: ***Nickel*** - **Nickel** is the most frequent cause of **metal-induced contact allergic dermatitis**, affecting a significant portion of the population. - It is commonly found in jewelry, belt buckles, buttons, and other everyday metallic objects. *Gold* - **Gold allergy** can occur but is much less common than nickel allergy. - Reactions typically arise from jewelry and may involve **allergic contact dermatitis**. *Silver* - **Silver allergy** is quite rare and often due to impurities or alloys rather than pure silver itself. - Pure silver is generally considered **hypoallergenic**. *Aluminum* - **Aluminum** is generally not a common cause of **allergic contact dermatitis**. - While it can be an irritant in some products (e.g., antiperspirants), true allergic reactions are infrequent.
Question 1386: 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?
- A. Personal or family history of atopy
- B. Elevated serum IgE levels
- C. Early age of onset (before 2 years)
- D. Chronic pruritic eczema with typical morphology and distribution (Correct Answer)
Explanation: ***Chronic pruritic eczema with typical morphology and distribution*** - The patient presents with **chronic**, **itchy**, **erythematous lesions** on the **flexural areas** (e.g., antecubital and popliteal fossae), characteristic of **atopic dermatitis** (eczema). - The **recurrence since childhood** and the typical distribution represent the **major diagnostic criteria** based on clinical morphology and distribution. - **Clinical presentation with typical morphology** is the **primary diagnostic criterion** according to Hanifin and Rajka criteria. *Elevated serum IgE levels* - While **elevated serum IgE** is often associated with atopic dermatitis, it is a **minor criterion** and a **laboratory finding**, not a primary diagnostic feature. - It reflects an **atopic predisposition**, but **clinical morphology and distribution** remain the most important diagnostic factors. *Personal or family history of atopy* - A **family history of asthma** (an atopic condition) is a **minor criterion** that supports the diagnosis of atopic dermatitis. - However, this is a **predisposing/supporting factor**, not as important as the characteristic clinical morphology and distribution. *Early age of onset (before 2 years)* - While atopic dermatitis often begins in **infancy or early childhood**, this is a **minor criterion** in the diagnostic framework. - The question states symptoms **recurring since childhood** but onset timing is less diagnostically important than the characteristic **clinical presentation** with typical morphology and distribution.
Question 1387: Which of the following conditions does NOT cause nail pitting?
- A. Lichen planus
- B. Fungal infection
- C. Pityriasis Rosea (Correct Answer)
- D. Psoriasis
Explanation: ***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.
Obstetrics and Gynecology
1 questionsAt which gestational week does the maximum volume of amniotic fluid occur?
NEET-PG 2013 - Obstetrics and Gynecology NEET-PG Practice Questions and MCQs
Question 1381: At which gestational week does the maximum volume of amniotic fluid occur?
- A. 32 weeks
- B. 34 weeks
- C. 36 weeks (Correct Answer)
- D. 40 weeks
Explanation: ***36 weeks*** - The volume of **amniotic fluid** gradually increases during pregnancy, reaching its **peak** around **36 weeks** of gestation. - After 36 weeks, the volume of amniotic fluid typically begins to **decrease** as the pregnancy approaches term. *32 weeks* - At 32 weeks, the amniotic fluid volume is still **increasing** and has not yet reached its maximum level. - The fetus is actively growing and contributing to fluid production, but the peak is still several weeks away. *34 weeks* - Although significant, the amniotic fluid volume at 34 weeks has not yet reached its **maximum**. - The volume will continue to rise for another two weeks before plateauing and then declining. *40 weeks* - By 40 weeks, a normal-term pregnancy, the volume of amniotic fluid has typically **decreased** from its peak at 36 weeks. - A declining amniotic fluid volume (oligohydramnios) can be a concern at term if it's too low.
Pathology
1 questionsWhat does a Tzanck smear in varicella-zoster virus infection typically show?
NEET-PG 2013 - Pathology NEET-PG Practice Questions and MCQs
Question 1381: What does a Tzanck smear in varicella-zoster virus infection typically show?
- A. Acantholytic cells
- B. Epidermal spongiosis
- C. Multinucleated giant cells (Correct Answer)
- D. Necrotic cells
Explanation: ***Multinucleated giant cells*** - A Tzanck smear identifies **multinucleated giant cells** with intranuclear inclusions, which are characteristic **cytopathic effects** of herpesviruses like VZV [1]. - These cells result from the fusion of infected keratinocytes, a hallmark finding in **herpes simplex** and **varicella-zoster infections** [1]. *Acantholytic cells* - Acantholytic cells are seen in conditions like **pemphigus vulgaris**, where there is loss of cell-to-cell adhesion between keratinocytes, leading to intraepidermal blistering. - While VZV can cause blistering, the primary cytological finding on Tzanck smear is not acantholysis but rather the presence of multinucleated cells. *Epidermal spongiosis* - Spongiosis refers to **intercellular edema** of epidermal cells, leading to widening of the intercellular spaces, typically seen in **eczematous dermatoses** [1]. - This finding is not specific to viral infections and does not represent the characteristic cytopathic effect of VZV on a Tzanck smear. *Necrotic cells* - Necrotic cells, or dead cells, are a general finding in many inflammatory and infectious processes where tissue damage occurs. - While VZV infection can lead to cell necrosis, the presence of isolated necrotic cells is not the specific, diagnostic feature for VZV on a Tzanck smear. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Infectious Diseases, pp. 366-367.
Pharmacology
1 questionsDepot preparations are administered by ?
NEET-PG 2013 - Pharmacology NEET-PG Practice Questions and MCQs
Question 1381: Depot preparations are administered by ?
- A. Subcutaneous route
- B. Intravenous route
- C. Intramuscular route
- D. Both subcutaneous and intramuscular route (Correct Answer)
Explanation: ***Both subcutaneous and intramuscular route*** - **Depot preparations** are designed for **sustained release** of medication over an extended period - This is achieved by forming a 'depot' in the tissue, often facilitated by a viscous vehicle or sparingly soluble form of the drug - Both **subcutaneous** and **intramuscular** tissues can sustain depot formulations effectively - **SC depot examples:** Insulin glargine, contraceptive implants (Nexplanon), leuprolide acetate - **IM depot examples:** Haloperidol decanoate, medroxyprogesterone acetate (Depo-Provera), paliperidone palmitate, long-acting risperidone *Subcutaneous route* - While some **depot preparations** are administered **subcutaneously**, it is not the *only* route for all depot formulations - The **subcutaneous tissue** offers relatively low blood flow, suitable for slow absorption - Alone, this option is incomplete as many depot preparations require IM administration *Intramuscular route* - Many **depot preparations** are given **intramuscularly** due to the muscle tissue's vascularity and tissue volume - The **muscle tissue** provides an excellent site for drug reservoir formation - Alone, this option is incomplete as some depot preparations are given subcutaneously *Intravenous route* - **Intravenous administration** is used for immediate and rapid drug delivery directly into the bloodstream - This route is **unsuitable for depot preparations** which require sustained release over time - No 'depot' can be formed with IV route as the drug is immediately diluted and distributed throughout the body