Dermatology
7 questionsAcanthosis nigricans is characterized by all of the following except?
Which of the following organisms has a role to play in Seborrheic dermatitis?
Pruritus is a feature of which of the following conditions?
Most common flexural site for atopic dermatitis -
Which of the following statements about Bowen's disease is correct?
Which of the following statements is true regarding pemphigus vulgaris?
Which of the following statements about actinic lichen planus is false?
NEET-PG 2015 - Dermatology NEET-PG Practice Questions and MCQs
Question 1061: Acanthosis nigricans is characterized by all of the following except?
- A. Associated with thick skin with hyperpigmentation
- B. May be a sign of internal malignancy
- C. Common in obese people
- D. Histologically there is hypermelanosis (Correct Answer)
Explanation: ***Histologically there is hypermelanosis*** - This statement is **FALSE** and is the correct answer to this "EXCEPT" question - The characteristic dark appearance of acanthosis nigricans is **NOT due to increased melanin** (hypermelanosis) - Histologically, the key features are **hyperkeratosis, papillomatosis, and mild acanthosis** - There is typically **minimal or no increase in melanocytes or melanin pigment** - The hyperpigmentation seen clinically is an optical effect from the thickened, hyperkeratotic epidermis *May be a sign of internal malignancy* - This statement is **true**; acanthosis nigricans can be a paraneoplastic syndrome associated with internal malignancies - **Malignant acanthosis nigricans** is particularly associated with **gastrointestinal adenocarcinomas** (especially gastric) - This form typically has sudden onset, rapid progression, and more widespread involvement *Common in obese people* - This statement is **true**; acanthosis nigricans is frequently associated with **insulin resistance** - Commonly seen in individuals with **obesity, type 2 diabetes, and metabolic syndrome** - This benign form typically affects flexural areas (neck, axillae, groin) *Associated with thick skin with hyperpigmentation* - This statement is **true**; these are the hallmark clinical features of acanthosis nigricans - Presents as **velvety thickening** and **dark brown to black hyperpigmentation** - Typically affects intertriginous areas and skin folds
Question 1062: Which of the following organisms has a role to play in Seborrheic dermatitis?
- A. Pityrosporum ovale (Correct Answer)
- B. Propionibacterium
- C. Candida albicans
- D. None of the above
Explanation: ***Pityrosporum ovale*** - **Pityrosporum ovale**, now known as **Malassezia furfur**, is a lipophilic yeast that colonizes the skin and plays a significant role in the pathogenesis of **seborrheic dermatitis**. - Its presence is commonly associated with the inflammatory response seen in seborrheic dermatitis, though the exact mechanism is not fully understood. *Candida albicans* - **Candida albicans** is a common cause of **mucocutaneous candidiasis** and **intertrigo**, but it is not directly implicated in the etiology of seborrheic dermatitis. - While it can cause skin infections, its typical presentation involves erythematous, macerated rashes with satellite lesions in skin folds. *Propionibacterium* - **Propionibacterium acnes**, now known as **Cutibacterium acnes**, is primarily associated with the pathogenesis of **acne vulgaris**. - It plays a role in the inflammation and comedone formation characteristic of acne, not the scaling and erythema of seborrheic dermatitis. *None of the above* - This option is incorrect because **Pityrosporum ovale (Malassezia furfur)** is a well-recognized organism involved in seborrheic dermatitis. - The other organisms listed are associated with different dermatological conditions.
Question 1063: Pruritus is a feature of which of the following conditions?
- A. Pemphigus foliaceous
- B. Pemphigus vulgaris
- C. Bullous pemphigoid (Correct Answer)
- D. None of the options
Explanation: ***Bullous pemphigoid*** - **Pruritus**, often severe, is a common and early symptom of bullous pemphigoid, often preceding the appearance of skin lesions. - The disease involves autoantibodies against **hemidesmosomal proteins** (BPAG1, BPAG2), leading to subepidermal blister formation. *Pemphigus foliaceous* - This condition is characterized by **superficial blistering** and erosions, but **pruritus is typically mild or absent**. - Blisters form in the **granular layer of the epidermis** due to autoantibodies against desmoglein 1. *Pemphigus vulgaris* - Patients with pemphigus vulgaris present with **flaccid blisters and erosions**, mainly affecting the skin and mucous membranes, but **pruritus is not a prominent feature**. - The disease involves intraepidermal blistering caused by autoantibodies targeting **desmoglein 3 (and sometimes desmoglein 1)**. *None of the options* - This option is incorrect, as **pruritus is a characteristic symptom of bullous pemphigoid**.
Question 1064: Most common flexural site for atopic dermatitis -
- A. Popliteal fossa
- B. Elbow crease (Correct Answer)
- C. Scalp
- D. Trunk
Explanation: ***Elbow crease*** - The **antecubital fossa** (elbow crease) and **popliteal fossa** (knee crease) are the **two most characteristic flexural sites** for atopic dermatitis in children and adults. - Both sites are **equally common** and represent classic presentations of flexural eczema. - The constant rubbing, friction, and moisture retention in these areas contribute to skin irritation and the characteristic **lichenification** seen in atopic dermatitis. - In the context of this question asking for "most common," both antecubital and popliteal fossae are considered the primary flexural sites. *Popliteal fossa* - The **popliteal fossa** (behind the knee) is equally as common as the antecubital fossa and is a classic flexural site for atopic dermatitis. - It shares the same pathophysiological mechanisms and clinical presentation as the elbow crease. - Both antecubital and popliteal fossae are mentioned together in standard dermatology texts as the hallmark flexural sites. *Scalp* - While the scalp can be affected by atopic dermatitis, especially in **infants** (as **seborrheic dermatitis** or cradle cap), it is **not a flexural site**. - Scalp involvement typically presents as scaling and erythema, rather than the lichenified plaques characteristic of flexural eczema. *Trunk* - The trunk can be affected by atopic dermatitis with diffuse patches or widespread xerosis, but it is **not a flexural site**. - Flexural areas (skin folds) are the characteristic locations for atopic dermatitis in the flexural pattern.
Question 1065: Which of the following statements about Bowen's disease is correct?
- A. Chronic sun exposure is a known risk factor.
- B. It is more common in fair-skinned individuals.
- C. There is a link between HSV infection and Bowen's disease.
- D. It is a form of squamous cell carcinoma in situ. (Correct Answer)
Explanation: ***It is a form of squamous cell carcinoma in situ.*** - **Bowen's disease** is, by definition, **squamous cell carcinoma in situ (SCC in situ)**. - It is characterized by full-thickness epidermal atypia of keratinocytes **without invasion through the basement membrane**. - This statement is **definitional** and represents the fundamental nature of what Bowen's disease is, making it the **best answer** among the options. *Chronic sun exposure is a known risk factor.* - This statement is **medically accurate**. Chronic UV exposure is indeed a well-established risk factor for Bowen's disease. - However, this describes a **risk factor** rather than defining what the condition is. - Other risk factors include **arsenic exposure**, **ionizing radiation**, **immunosuppression**, and **HPV infection** (particularly in anogenital sites). - While true, this is not as fundamental as the definitional statement. *It is more common in fair-skinned individuals.* - This statement is also **medically accurate**. Bowen's disease occurs more frequently in fair-skinned individuals (Fitzpatrick skin types I-II). - Fair skin provides less melanin protection against UV damage, increasing susceptibility to various forms of skin cancer including Bowen's disease. - However, this describes **epidemiology** rather than defining the condition itself. *There is a link between HSV infection and Bowen's disease.* - This statement is **incorrect**. There is **no established association** between Herpes Simplex Virus (HSV) and Bowen's disease. - **Human Papillomavirus (HPV)**, particularly high-risk types 16 and 18, is associated with Bowen's disease, especially in anogenital locations. - This represents a common confusion between HSV and HPV.
Question 1066: Which of the following statements is true regarding pemphigus vulgaris?
- A. It primarily affects the dermal-epidermal junction.
- B. It is a subepidermal blistering disease.
- C. It is an intraepidermal blistering disease. (Correct Answer)
- D. Antibodies are formed against basement membrane proteins.
Explanation: ***It is an intraepidermal blistering disease.*** - **Pemphigus vulgaris** is characterized by the formation of blisters *within the epidermis* due to the loss of cell-to-cell adhesion between **keratinocytes**. - This **acantholysis** results from autoantibodies targeting **desmosomes**, specifically **desmoglein 1 and 3**. *It is a subepidermal blistering disease.* - This statement is incorrect as it describes conditions like **bullous pemphigoid** or **dermatitis herpetiformis**, where blisters form *below* the epidermis. - In pemphigus vulgaris, the separation occurs *above* the basement membrane within the epidermal layer. *It primarily affects the dermal-epidermal junction.* - This is characteristic of **bullous pemphigoid** or **epidermolysis bullosa acquisita**, where the primary pathology involves the separation at the interface between the dermis and epidermis. - Pemphigus vulgaris directly affects the adhesion *within* the epidermis itself. *Antibodies are formed against basement membrane proteins.* - This is characteristic of **bullous pemphigoid**, where autoantibodies target components of the **basement membrane zone**, such as **BP180** and **BP230**. - In pemphigus vulgaris, the autoantibodies target **desmogleins** on the surface of keratinocytes, not basement membrane proteins.
Question 1067: Which of the following statements about actinic lichen planus is false?
- A. Associated with severe pruritus (Correct Answer)
- B. Violaceous brown papules
- C. Usually affects exposed areas of body
- D. Autoimmune etiology
Explanation: ***Associated with severe pruritus*** - While other forms of lichen planus, especially the typical cutaneous type, are often associated with **severe pruritus**, actinic lichen planus is typically characterized by **mild or absent pruritus**. - Its presentation is often more focused on pigmentary changes and papules in sun-exposed areas rather than intense itching. *Autoimmune etiology* - **Lichen planus**, including its actinic variant, is recognized as an **autoimmune disease**. - It involves a **T-cell-mediated immune response** against basal keratinocytes. *Violaceous brown papules* - Actinic lichen planus commonly presents with **violaceous, brown, or hyperpigmented papules and plaques**. - These lesions often exhibit a subtle **annular or reticulated pattern**. *Usually affects exposed areas of body* - As its name suggests ("actinic" referring to light), this variant of lichen planus preferentially affects **sun-exposed areas** such as the face, neck, and dorsal hands. - This distribution distinguishes it from classic lichen planus, which can occur anywhere but often affects the flexor surfaces of the wrists, ankles, and oral mucosa.
Internal Medicine
2 questionsWhich of the following is characterized by a solitary painless ulcer on genitalia?
What is the normal range for maximum phonation time in healthy adults?
NEET-PG 2015 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 1061: Which of the following is characterized by a solitary painless ulcer on genitalia?
- A. Genital herpes
- B. Syphilis (Correct Answer)
- C. Traumatic injury
- D. Chancroid
Explanation: ***Syphilis*** - Primary syphilis typically presents as a **painless chancre** (ulcer) at the site of infection, usually the **genitalia**. - The painless nature is a key differentiating feature as it often goes unnoticed, allowing the disease to progress. *Genital herpes* - Characterized by multiple, small, often painful vesicles or ulcers that may coalesce [1]. - Lesions are typically tender or painful, unlike the **painless chancre** of syphilis [1]. *Traumatic injury* - While a traumatic injury can cause a solitary ulcer, it is usually painful and often associated with a clear history of trauma. - The ulcer's morphology and healing process may differ from a classic syphilitic chancre. *Chancroid* - Caused by *Haemophilus ducreyi*, chancroid presents as one or more painful, tender ulcers with ragged, undermined borders. - This is a significant differentiator from the **painless ulcer** seen in primary syphilis.
Question 1062: What is the normal range for maximum phonation time in healthy adults?
- A. 15-25 seconds
- B. 40-45 seconds
- C. 30-35 seconds (Correct Answer)
- D. 8-12 seconds
Explanation: ***30-35 seconds*** - The **maximum phonation time (MPT)** is a measure of the longest period a person can sustain a vowel sound on a single breath. - A healthy adult typically has an MPT in the range of **30-35 seconds**, reflecting good respiratory and phonatory control. *8-12 seconds* - This range is generally considered **below normal** for a healthy adult and may indicate compromised **respiratory support** or **laryngeal function**. - A short MPT could be a sign of **vocal fold pathology** or **reduced breath support**. *15-25 seconds* - While better than 8-12 seconds, this range is still often considered **slightly lower than optimal** for healthy adults. - It might suggest subtle inefficiencies in **breath control** or **vocal fold coaptation**, though it's not severely pathological. *40-45 seconds* - An MPT in this range is **unusually long** and exceeds the typical normal values for most healthy adults. - While seemingly good, excessively long MPTs are not standard and might suggest unusual respiratory capacity or an outlier measurement.
Pharmacology
1 questionsWhich of the following drugs can lead to pemphigus?
NEET-PG 2015 - Pharmacology NEET-PG Practice Questions and MCQs
Question 1061: Which of the following drugs can lead to pemphigus?
- A. Carbamazepine
- B. Penicillamine (Correct Answer)
- C. Isoniazid
- D. Furosemide
Explanation: ***Penicillamine*** - **Penicillamine** is a well-known drug that can induce **pemphigus**, often through mechanisms involving alterations in **desmosome structure** or function. - The drug's sulfhydryl groups are thought to interfere with the integrity of **desmoglein proteins**, leading to blister formation. *Isoniazid* - **Isoniazid** is a first-line antituberculosis drug primarily associated with **hepatotoxicity** and **peripheral neuropathy**. - It is not typically implicated in the development of **pemphigus**. *Carbamazepine* - **Carbamazepine** is an anticonvulsant that can cause various cutaneous reactions, most notably **Stevens-Johnson syndrome (SJS)** and **toxic epidermal necrolysis (TEN)**. - While it can cause severe skin reactions, **pemphigus** is not a common side effect of carbamazepine. *Furosemide* - **Furosemide** is a loop diuretic that can cause **photosensitivity**, rashes, and rarely, severe skin reactions like **erythema multiforme**. - It is not recognized as a drug that induces **pemphigus**.