Q.1 Which type of psoriasis is most commonly observed?
Plaque psoriasis
Guttate psoriasis
Inverse psoriasis
Pustular psoriasis
Explanation - Plaque psoriasis (psoriasis vulgaris) is the most common form, seen in about 80–90% of cases.
Correct answer is: Plaque psoriasis
Q.2 What is the hallmark histological feature of psoriasis?
Acantholysis
Auspitz sign
Parakeratosis
Spongiosis
Explanation - Parakeratosis, or retention of nuclei in the stratum corneum, is a key histological finding in psoriasis.
Correct answer is: Parakeratosis
Q.3 Which nail change is most characteristic of psoriasis?
Onycholysis
Pitting
Subungual hyperkeratosis
Beau’s lines
Explanation - Nail pitting, small depressions on the nail surface, is highly suggestive of psoriasis.
Correct answer is: Pitting
Q.4 Which genetic marker is strongly associated with psoriasis?
HLA-B27
HLA-DR4
HLA-Cw6
HLA-B8
Explanation - HLA-Cw6 is strongly associated with psoriasis, especially early-onset cases.
Correct answer is: HLA-Cw6
Q.5 Which of the following is a known trigger for psoriasis flare-ups?
Sun exposure
Streptococcal infection
Hypothyroidism
Iron deficiency
Explanation - Streptococcal throat infection often precipitates guttate psoriasis.
Correct answer is: Streptococcal infection
Q.6 What is Auspitz sign?
Appearance of scales after scratching
Pinpoint bleeding when scales are removed
Silvery scales on plaques
Koebner phenomenon
Explanation - Auspitz sign is pinpoint bleeding due to exposure of dermal capillaries after scale removal.
Correct answer is: Pinpoint bleeding when scales are removed
Q.7 Which drug is commonly associated with worsening psoriasis?
Methotrexate
Lithium
Corticosteroids (topical)
Azathioprine
Explanation - Lithium is well known to exacerbate or trigger psoriasis.
Correct answer is: Lithium
Q.8 Which type of psoriasis is considered a dermatologic emergency?
Plaque psoriasis
Guttate psoriasis
Pustular psoriasis
Erythrodermic psoriasis
Explanation - Erythrodermic psoriasis can cause widespread skin involvement and systemic complications, making it an emergency.
Correct answer is: Erythrodermic psoriasis
Q.9 What phenomenon describes psoriatic lesions appearing at sites of trauma?
Auspitz phenomenon
Koebner phenomenon
Darier’s sign
Pathergy
Explanation - The Koebner phenomenon refers to psoriatic lesions appearing at areas of trauma.
Correct answer is: Koebner phenomenon
Q.10 Which systemic comorbidity is most closely linked to psoriasis?
Asthma
Rheumatoid arthritis
Psoriatic arthritis
Systemic lupus erythematosus
Explanation - Psoriatic arthritis affects up to 30% of patients with psoriasis.
Correct answer is: Psoriatic arthritis
Q.11 Which cytokine pathway is most important in the pathogenesis of psoriasis?
IL-4/IL-5
IL-17/IL-23
IL-2/IFN-γ
TNF-α only
Explanation - The IL-17/IL-23 pathway is central in driving psoriatic inflammation.
Correct answer is: IL-17/IL-23
Q.12 Which biologic drug targets TNF-α in psoriasis treatment?
Ustekinumab
Etanercept
Secukinumab
Apremilast
Explanation - Etanercept is a TNF-α inhibitor used for moderate to severe psoriasis.
Correct answer is: Etanercept
Q.13 Which vitamin D analog is used topically in psoriasis?
Tacalcitol
Calcipotriol
Calcitonin
Calcitriol
Explanation - Calcipotriol is a vitamin D analog widely used in topical psoriasis treatment.
Correct answer is: Calcipotriol
Q.14 Which clinical feature best describes plaque psoriasis?
Well-demarcated erythematous plaques with silvery scales
Poorly defined macules with vesicles
Hypopigmented patches with scaling
Painful ulcers with eschar
Explanation - This is the hallmark presentation of plaque psoriasis.
Correct answer is: Well-demarcated erythematous plaques with silvery scales
Q.15 Which systemic therapy is contraindicated in pregnancy for psoriasis?
Methotrexate
Cyclosporine
Phototherapy
Biologics
Explanation - Methotrexate is teratogenic and contraindicated in pregnancy.
Correct answer is: Methotrexate
Q.16 Which site is most typically affected in inverse psoriasis?
Elbows
Knees
Flexural areas
Scalp
Explanation - Inverse psoriasis affects intertriginous (flexural) areas like groin and axillae.
Correct answer is: Flexural areas
Q.17 What is the role of phototherapy in psoriasis?
Worsens psoriasis
Reduces inflammation and keratinocyte proliferation
Has no effect
Used only in erythrodermic psoriasis
Explanation - Narrowband UVB phototherapy is effective in reducing inflammation and abnormal skin turnover.
Correct answer is: Reduces inflammation and keratinocyte proliferation
Q.18 Which form of psoriasis is most strongly linked with streptococcal throat infections?
Plaque psoriasis
Guttate psoriasis
Pustular psoriasis
Inverse psoriasis
Explanation - Guttate psoriasis is often triggered by streptococcal infection.
Correct answer is: Guttate psoriasis
Q.19 Which topical agent is most commonly first-line in mild psoriasis?
Topical steroids
Coal tar
Tacrolimus
Retinoids
Explanation - Topical corticosteroids are usually first-line therapy for mild psoriasis.
Correct answer is: Topical steroids
Q.20 Which laboratory abnormality is commonly associated with systemic psoriasis?
Elevated uric acid
Anemia
Thrombocytopenia
Hypercalcemia
Explanation - Hyperuricemia may occur due to high cell turnover in psoriasis.
Correct answer is: Elevated uric acid
Q.21 Which joint involvement is typical of psoriatic arthritis?
Symmetric polyarthritis
Asymmetric oligoarthritis
Monoarthritis of knee
Migratory arthritis
Explanation - Psoriatic arthritis often presents as asymmetric oligoarthritis.
Correct answer is: Asymmetric oligoarthritis
Q.22 What is the mechanism of action of Apremilast in psoriasis?
TNF-α inhibition
IL-17 blockade
PDE-4 inhibition
IL-23 blockade
Explanation - Apremilast is an oral phosphodiesterase-4 inhibitor used in psoriasis.
Correct answer is: PDE-4 inhibition
Q.23 Which of the following is NOT a first-line therapy for moderate to severe psoriasis?
Methotrexate
Cyclosporine
Acitretin
Topical emollients
Explanation - While emollients are supportive, they are not sufficient as first-line therapy in moderate-severe disease.
Correct answer is: Topical emollients
Q.24 Which body area is least likely to be affected by psoriasis?
Scalp
Elbows
Knees
Palms
Explanation - Although palm involvement can occur, it is much less common compared to scalp, elbows, and knees.
Correct answer is: Palms
Q.25 Which factor reduces the severity of psoriasis?
Winter season
Stress
HIV infection
Sunlight exposure
Explanation - UV light from sunlight often improves psoriatic lesions.
Correct answer is: Sunlight exposure