Autoimmune Skin Diseases Practice Questions

Q: A 35-year-old woman consulted a dermatologist due to a persistent facial rash. Physical examination revealed an erythematous rash, without blistering or ulceration, involving both cheeks and the nose, with the nasolabial folds relatively spared. The dermatologist also noted scattered erythematous, firm, maculopapular lesions on the face, neck, upper chest, and elbows, as well as focal alopecia on the scalp. The patient reported that the rash had been present for approximately six months, with exacerbation upon exposure to sunlight. Which autoimmune disease would MOST likely produce this patient's skin problems?

Systemic lupus erythematosus. ***Systemic lupus erythematosus*** - The **malar rash** (sparing the nasolabial folds) and photosensitivity are classic dermatological findings in **systemic lupus erythematosus (SLE)**. - **Focal alopecia** and other **maculopapular lesions** are also characteristic skin manifestations of SLE. *Dermatomyositis* - While dermatomyositis can also present with photosensitive rashes, the typical facial involvement includes **heliotrope rash** around the eyes or **Gottron's papules** over bony prominences. - The description of a malar rash sparing nasal folds and scattered maculopapular lesions is less consistent with dermatomyositis. *Progressive systemic sclerosis* - This condition is primarily characterized by **skin thickening and hardening** (scleroderma), often starting in the extremities and face. - The described **erythematous rash** with separate maculopapular lesions and alopecia is not typical for progressive systemic sclerosis. *Rheumatoid arthritis* - Rheumatoid arthritis is a chronic inflammatory joint disease and does **not typically present with primary dermatological manifestations** like the facial rash, photosensitivity, or alopecia described. - While some skin findings can occur (e.g., rheumatoid nodules), they are not the prominent features described.

Q: A 85-year-old woman has large blistering lesions on the abdomen and thighs that come and go without therapy, and Nikolsky sign is negative. Which of the following is the most likely diagnosis?

bullous pemphigoid. ***Bullous pemphigoid*** - This condition typically affects **elderly individuals** with large, tense bullae that often resolve spontaneously and a negative **Nikolsky sign**. - **Immunofluorescence** shows IgG and C3 deposits along the **dermal-epidermal junction**. *Pemphigus vulgaris* - Characterized by **flaccid bullae** that rupture easily and a **positive Nikolsky sign**, which is not seen here. - Patients are usually younger and involvement of **mucous membranes** is common. *Dermatitis herpetiformis* - This condition presents with **pruritic papulovesicular lesions** arranged in a herpetiform pattern. - It is associated with **celiac disease** and responds to a gluten-free diet. *Herpes gestationis* - Also known as **pemphigoid gestationis**, this rare autoimmune blistering disease occurs during **pregnancy or postpartum**. - It presents with **urticarial plaques and bullae**, primarily on the abdomen and extremities, but is not relevant to an 85-year-old woman.

Q: Which of the following HLA types is associated with dermatitis herpetiformis?

HLA B8. ***HLA B8*** - **HLA B8** is associated with **dermatitis herpetiformis**, an autoimmune blistering skin condition characterized by intensely pruritic vesicles. - HLA B8 is part of the extended haplotype (HLA-A1, B8, DR3, DQ2) commonly found in patients with dermatitis herpetiformis. - The **strongest association** is actually with **HLA-DQ2** and **HLA-DQ8** (found in ~95% of DH patients), as DH is closely linked with **celiac disease** and shares the same HLA associations. - Among the options listed, **HLA B8** is the one with a recognized association. *HLA A5* - **HLA A5** has no established association with **dermatitis herpetiformis**. - It is not considered a genetic risk factor for this condition. *HLA A28* - **HLA A28** has no significant association with **dermatitis herpetiformis**. - It does not confer increased susceptibility to this autoimmune blistering disorder. *HLA B27* - **HLA B27** is strongly associated with **seronegative spondyloarthropathies** including **ankylosing spondylitis**, **reactive arthritis**, and **psoriatic arthritis**. - It is not associated with dermatitis herpetiformis or other autoimmune blistering diseases.

Q: Lupus pernio is a characteristic skin manifestation of which condition?

Sarcoidosis. ***Sarcoidosis*** - **Lupus pernio** is considered a **pathognomonic** and chronic cutaneous manifestation of sarcoidosis, characterized by violaceous plaques on the nose, cheeks, lips, and ears. - Its presence often indicates a **more severe and chronic course** of sarcoidosis, frequently associated with systemic involvement, particularly in the respiratory tract. *Tuberculosis* - While tuberculosis can cause various skin manifestations, such as **lupus vulgaris** (a form of cutaneous tuberculosis), it does not typically present as lupus pernio. - **Lupus vulgaris** involves granulomatous lesions, but their appearance and distribution differ from lupus pernio. *Carcinoid syndrome* - Carcinoid syndrome is characterized by symptoms like **flushing**, diarrhea, and bronchospasm, primarily due to the release of vasoactive substances like serotonin. - It does not present with **lupus pernio** or similar skin lesions of a granulomatous nature. *Lymphoma* - Cutaneous lymphomas can manifest as various skin lesions, including **plaques, nodules, or tumors**, depending on the specific type of lymphoma. - However, **lupus pernio** with its characteristic violaceous color and location is not a typical presentation of lymphoma.

Q: Gluten-free diet is beneficial in:

Dermatitis herpetiformis. ***Dermatitis herpetiformis*** - This condition is a **cutaneous manifestation of celiac disease**, presenting with intensely itchy, vesicular lesions. - A strict **gluten-free diet** is the cornerstone of treatment, leading to improvement in both skin lesions and underlying enteropathy. *Psoriasis* - While some research explores a potential link between diet and psoriasis, a **gluten-free diet is not a primary or universally recognized treatment** for psoriasis. - Psoriasis is primarily an **immune-mediated inflammatory skin disease** with various treatment modalities, but not specifically gluten restriction. *Exfoliative dermatitis* - Also known as **erythroderma**, this is a severe inflammatory skin condition characterized by generalized redness and scaling of the skin. - It has diverse causes including other dermatoses, drug reactions, and lymphoma, but is **not linked to gluten sensitivity** or improved by a gluten-free diet. *Pemphigoid* - **Bullous pemphigoid** is an autoimmune blistering skin disease caused by antibodies targeting components of the basement membrane. - The treatment typically involves **corticosteroids and immunosuppressants**, with no established role for a gluten-free diet.

Q: Fogo selvagem is a type of:

Pemphigus foliaceus. ***Pemphigus foliaceus*** - **Fogo selvagem** is the endemic form of pemphigus foliaceus found in Brazil, characterized by **superficial blistering**. - It involves **autoantibodies** against **desmoglein 1**, leading to separation within the superficial epidermis. *Pemphigus vulgaris* - This autoimmune blistering disease is characterized by autoantibodies against **desmoglein 1 and 3**, leading to **deep epidermal blisters**. - Patients typically present with **mucosal lesions** and flaccid blisters that rupture easily, which differs from the superficial cutaneous blistering of fogo selvagem. *Pemphigus vegetans* - This is a rare variant of **Pemphigus vulgaris**, characterized by verrucous plaques and hypertrophic vegetations, particularly in intertriginous areas. - While it's a form of pemphigus, it has distinct clinical features that differentiate it from the superficial blistering seen in fogo selvagem. *Bullous pemphigoid* - This condition involves **subepidermal blistering** due to autoantibodies targeting hemidesmosomes, specifically BP180 and BP230. - Clinically, it presents with tense blisters and is distinct from the intraepidermal blistering of pemphigus types.

Question 1

A 35-year-old woman consulted a dermatologist due to a persistent facial rash. Physical examination revealed an erythematous rash, without blistering or ulceration, involving both cheeks and the nose, with the nasolabial folds relatively spared. The dermatologist also noted scattered erythematous, firm, maculopapular lesions on the face, neck, upper chest, and elbows, as well as focal alopecia on the scalp. The patient reported that the rash had been present for approximately six months, with exacerbation upon exposure to sunlight. Which autoimmune disease would MOST likely produce this patient's skin problems?

Accepted Answer

Systemic lupus erythematosus

Answer

Dermatomyositis

Answer

Progressive systemic sclerosis

Answer

Rheumatoid arthritis

Question 2

A 85-year-old woman has large blistering lesions on the abdomen and thighs that come and go without therapy, and Nikolsky sign is negative. Which of the following is the most likely diagnosis?

Accepted Answer

bullous pemphigoid

Answer

pemphigus vulgaris

Answer

dermatitis herpetiformis

Answer

herpes gestationis

Question 3

Which of the following HLA types is associated with dermatitis herpetiformis?

Accepted Answer

HLA B8

Answer

HLA A5

Answer

HLA A28

Answer

HLA B27

Question 4

Lupus pernio is a characteristic skin manifestation of which condition?

Accepted Answer

Sarcoidosis

Answer

Tuberculosis

Answer

Carcinoid syndrome

Answer

Lymphoma

Question 5

Gluten-free diet is beneficial in:

Accepted Answer

Dermatitis herpetiformis

Answer

Exfoliative dermatitis

Answer

Psoriasis

Answer

Pemphigoid

Question 6

Fogo selvagem is a type of:

Accepted Answer

Pemphigus foliaceus

Answer

Pemphigus vulgaris

Answer

Bullous pemphigoid

Answer

Pemphigus vegetans

Autoimmune Skin Diseases — MCQs

Autoimmune Skin Diseases — MCQs

On this page

Practice by Chapter

Want unlimited practice?