1. Cells present in the epidermis include:

• A. Keratinocyte. (Correct)
  Keratinocytes are the predominant cells in the epidermis, responsible for forming the barrier against environmental damage and producing keratin.

• B. Epidermocytes. (Incorrect)
  This is not a term used to describe cells of the epidermis. It is a misnomer.

• C. Lymphocyte. (Incorrect)
  Lymphocytes are found in the dermis as part of the immune system but are not intrinsic to the epidermis.

• D. Adipocytes. (Incorrect)
  Adipocytes are present in the subcutaneous layer, not in the epidermis.

2. In the epidermis:

• D. All layers are derived from the basal cell layer. (Correct)
  The basal layer contains stem cells that divide and give rise to all other layers of the epidermis.

• A. Stratum corneum normally is formed of nucleated cells. (Incorrect)
  The stratum corneum is formed of enucleated, keratinized cells.

• B. Blood vessels are numerous. (Incorrect)
  The epidermis is avascular; blood vessels are present in the dermis.

• C. There are no other cells than keratinocytes. (Incorrect)
  Other cells like melanocytes and Langerhans cells are also present in the epidermis.

3. The basal cell layer of the epidermis is composed of:

• C. A single row of cells. (Correct)
  The basal layer consists of a single row of cuboidal or columnar cells responsible for regeneration of the epidermis.

• A. Sweat and sebaceous glands. (Incorrect)
  These are present in the dermis, not the basal layer.

• B. Collagen fibers. (Incorrect)
  Collagen fibers are part of the dermis.

• D. Two rows of dividing cells. (Incorrect)
  The basal layer only has a single row of dividing cells.

4. Which statement is true regarding structure and function of the skin?

• B. Corneal layer is absent in mucous membranes. (Correct)
  Mucous membranes lack a stratum corneum, which is a characteristic of keratinized skin.

• A. Dark-skin people have more number of melanocytes. (Incorrect)
  All humans have a similar number of melanocytes; differences in skin color are due to the activity and type of melanin produced.

• C. Chronic exposure to the sun may induce thinning of the skin. (Incorrect)
  Chronic sun exposure thickens the skin due to increased keratinization.

• D. Skin has a minor role as body water storage. (Incorrect)
  The skin acts as a barrier to water loss but does not store water.

5. Concerning thickness of the skin:

• C. Scrotum and eyelids are the most thinner skin. (Correct)
  The skin of the scrotum and eyelids is among the thinnest in the body.

• A. Is thinner on the extensor surfaces. (Incorrect)
  The skin is generally thinner on the flexor surfaces.

• B. Is thicker on the flexor surfaces. (Incorrect)
  The extensor surfaces typically have thicker skin.

• D. All parts of the body have the same thickness. (Incorrect)
  The thickness of skin varies across different body areas.

6. Eccrine and apocrine sweat glands:

• A. Provide excretion of odiferous substances. (Correct)
  Apocrine glands are associated with odiferous (smelly) sweat, while eccrine glands mainly regulate temperature.

• B. Are active always and rarely become inactive. (Incorrect)
  Apocrine glands become active at puberty, and eccrine glands are regulated by environmental and internal factors.

• C. Contribute to most of urea excretion, minimal is through kidneys. (Incorrect)
  Kidneys are the primary route of urea excretion.

• D. Prevent transepidermal water loss. (Incorrect)
  Sweat glands are not responsible for preventing transepidermal water loss; this is mainly a function of the stratum corneum.

7. Wheal is the primary lesion of:

• C. Urticaria. (Correct)
  A wheal is a transient, raised, edematous lesion often seen in urticaria (hives).

• A. Eczema. (Incorrect)
  Eczema primarily presents with vesicles, papules, or plaques.

• B. Acne vulgaris. (Incorrect)
  Acne is characterized by comedones, papules, and pustules.

• D. Heat rash. (Incorrect)
  Heat rash (miliaria) typically presents as vesicles or pustules, not wheals.

8. Stratum lucidum is normally present in:

• B. Palms and soles. (Correct)
  Stratum lucidum is present in thick, glabrous (hairless) skin of palms and soles.

• A. The face. (Incorrect)
  The face has thin skin without a stratum lucidum.

• C. Eyelids and scrotum. (Incorrect)
  These areas have thin skin.

• D. Upper back and shoulder. (Incorrect)
  While these areas have thicker skin, they lack a stratum lucidum.

9. Concerning dermis layer of the skin:

• C. Dermal papillae contain blood vessels. (Correct)
  The dermal papillae, located in the papillary layer, supply nutrients to the avascular epidermis.

• A. Reticular layer is a thin upper layer, composed of haphazardly arranged collagen fibers. (Incorrect)
  The reticular layer is a thicker, lower layer with dense collagen fibers arranged haphazardly.

• B. Papillary layer is a thick lower layer, composed of collagen fibers arranged parallel to the surface of the skin. (Incorrect)
  The papillary layer is the thin upper layer with loose connective tissue.

• D. Contain melanocytes which give the skin its color. (Incorrect)
  Melanocytes are located in the basal layer of the epidermis.

10. The Keratinization process:
B. Is the travel of cells from basal layer to corneal layer with formation of keratin.

• Explanation: Keratinization is the process where keratinocytes in the basal layer of the epidermis travel upward, losing their nuclei and forming keratin, a structural protein. This process creates the protective outer layer of the skin.

• Why not others?

  • A: The nucleus does not increase in size; it is degraded as the cells travel upwards.

  • C: The process involves gaining keratin, not losing it.

  • D: Cell division occurs in the basal layer, not the corneal layer.

11. Tinea incognito:
C. Modified lesions of tinea corporis due to use of topical corticosteroids.

• Explanation: Tinea incognito results when dermatophyte infections are misdiagnosed and treated with topical corticosteroids, leading to an altered and less typical presentation.

• Why not others?

  • A: This does not describe the unique presentation of tinea incognito.

  • B: The term "incognito" refers to the modified presentation, not an unknown cause.

  • D: Topical steroids worsen fungal infections rather than treating them.

12. Tinea corporis:
B. Appears as a patch with elevated margins that increase in size with central healing.

• Explanation: Tinea corporis is a superficial fungal infection of the body. Its characteristic lesion is a ring-shaped patch with active edges and central clearing.

• Why not others?

  • A: Papules are not the hallmark lesion.

  • C: The face can be affected.

  • D: Tinea corporis affects any part of the body, excluding palms and soles.

13. Pityriasis rosea:
C. Is a self-limiting disease.

• Explanation: Pityriasis rosea is a self-limiting skin condition that typically resolves on its own in about 6–8 weeks. It often starts with a "herald patch."

• Why not others?

  • A: It does not lead to significant complications if untreated.

  • B: It is not a fungal infection and thus not treated with antifungals.

  • D: It is thought to have a viral etiology but is not contagious.

14. Systemic antifungal is essential in the treatment of:
B. Tinea unguium & tinea capitis.

• Explanation: Tinea unguium (onychomycosis) and tinea capitis often require systemic antifungals for effective treatment, as topical treatments are insufficient for these deeper infections.

• Why not others?

  • A, C, and D: Topical antifungals are usually sufficient for superficial infections like tinea corporis, tinea cruris, and tinea pedis.

15. Pityriasis versicolor is:
D. Occurs predominantly in areas rich in sebaceous glands.

• Explanation: Pityriasis versicolor is caused by Malassezia, a lipophilic yeast that thrives in sebaceous gland-rich areas like the chest, back, and shoulders.

• Why not others?

  • A: It is treatable with antifungals.

  • B: The cause is known (Malassezia furfur).

  • C: It commonly affects adolescents and adults, not prepubertal children.

16. Pityrosporum ovale (Malassezia furfur):
A. Is the causative organism of pityriasis versicolor and scalp dandruff.

• Explanation: Malassezia furfur is implicated in pityriasis versicolor and dandruff. It is a yeast that colonizes sebaceous areas.

• Why not others?

  • B: The "Christmas tree pattern" describes pityriasis rosea, not Malassezia.

  • C: Topical antibiotics are ineffective against Malassezia.

  • D: Malassezia is not a dermatophyte but a yeast.

17. Laboratory confirmation of dermatophyte infections include:
C. Potassium hydroxide examination.

• Explanation: Potassium hydroxide (KOH) dissolves keratin, allowing microscopic visualization of fungal hyphae, which confirms dermatophyte infection.

• Why not others?

  • A: Skin biopsy is rarely needed for dermatophyte infections.

  • B and D: Sodium hydroxide is not used in this context; skin smears are non-specific.

18. Tinea pedis:
C. Many cases will need a combination of topical antifungal and topical antibiotic.

• Explanation: Tinea pedis (athlete’s foot) can become superinfected with bacteria, necessitating the use of both antifungal and antibiotic treatments.

• Why not others?

  • A: It affects feet, not hands.

  • B: The 4th–5th webs are the most common infection sites.

  • D: Non-dermatophytes can also cause similar conditions.

19. Herald (mother) patch is seen:
D. Pityriasis rosea.

• Explanation: A herald patch is the initial large, scaly lesion seen in pityriasis rosea, often followed by a generalized rash in a "Christmas tree pattern."

• Why not others?

  • A, B, C: These conditions do not have a herald patch.

20. Impetigo contagiosum:
D. Is a common bacterial infection of children.

• Explanation: Impetigo is a superficial bacterial skin infection, most common in children, caused by Staphylococcus aureus or Streptococcus pyogenes.

• Why not others?

  • A: It is not caused by a poxvirus.

  • B: It usually affects exposed areas.

  • C: Itching is not always present.

21. The drug of choice in pityriasis versicolor is:
C. Ketoconazole.

• Explanation: Ketoconazole, either in oral or topical form, is the most effective treatment for pityriasis versicolor, caused by Malassezia. It eradicates the yeast and prevents recurrence.

• Options explained:

  • A. Griseofulvin: Effective for dermatophyte infections but not for pityriasis versicolor.

  • B. Terbinafine: Works for dermatophytes but is not effective against Malassezia.

  • D. Penicillin: An antibiotic, irrelevant for fungal infections.

22. Erythema nodosum:
B. Is an example of septal panniculitis.

• Explanation: Erythema nodosum is a type of septal panniculitis (inflammation of the fat septa) and often manifests as tender, red nodules on the shins.

• Options explained:

  • A. Caused by viral infection exclusively: Incorrect, as it has multiple causes, including infections, drugs, and systemic diseases.

  • C. Is a rare skin manifestation: It is relatively common, especially in certain systemic diseases like sarcoidosis.

  • D. Is a vesiculobullous condition: Incorrect, as it is a nodular condition.

23. Nikolsky's sign is:
A. Positive in toxic epidermal necrolysis.

• Explanation: Nikolsky’s sign is positive when gentle lateral pressure on normal-looking skin causes the epidermis to shear off. It is seen in conditions like toxic epidermal necrolysis (TEN) and pemphigus vulgaris.

• Options explained:

  • B. Negative in staphylococcal scalded skin syndrome: Incorrect, as it is also positive in SSSS.

  • C. Positive in lichen planus: Incorrect, as lichen planus does not show this sign.

  • D. Negative in pemphigus vulgaris: Incorrect, as it is positive in pemphigus vulgaris.

24. Koebner phenomenon:
D. All of the above.

• Explanation: The Koebner phenomenon is the appearance of lesions of an existing skin condition at sites of trauma. It is seen in psoriasis, lichen planus, and vitiligo.

• Options explained:

  • A. Is seen in psoriasis: Correct.

  • B. Is seen in lichen planus: Correct.

  • C. Is seen in vitiligo: Correct.

  • D. All of the above: Correct, as it encompasses all three conditions.

25. Psoriasis can be associated with all except:
D. Koebner phenomenon is not seen.

• Explanation: Psoriasis is associated with nail changes, psoriatic arthritis, and guttate psoriasis. Koebner phenomenon is seen in psoriasis, so option D is incorrect.

• Options explained:

  • A. Nail changes: Correct; nail pitting and onycholysis are common.

  • B. Psoriatic arthritis: Correct; it occurs in a subset of patients.

  • C. Guttate psoriasis: Correct; a subtype of psoriasis often triggered by infection.

  • D. Koebner phenomenon is not seen: Incorrect, as it is seen in psoriasis.

26. Treatment for guttate psoriasis is:
B. Narrow-band ultraviolet B (NBUVB) therapy.

• Explanation: NBUVB therapy is an effective treatment for guttate psoriasis, a condition characterized by small, droplet-shaped lesions often triggered by a streptococcal infection.

• Options explained:

  • A. Topical corticosteroids: Effective for localized psoriasis but not ideal for extensive guttate psoriasis.

  • C. Oral antibiotics: Only used to treat underlying streptococcal infection, not the psoriasis itself.

  • D. Topical coal tar: An older treatment with limited efficacy compared to NBUVB.

27. Treatment of erythrodermic psoriasis includes:
A. Systemic immunosuppressants like cyclosporine.

• Explanation: Erythrodermic psoriasis is a severe form requiring systemic immunosuppressants like cyclosporine to control inflammation.

• Options explained:

  • B. Narrow-band UVB therapy: Contraindicated in erythroderma due to the extensive nature of the lesions.

  • C. Topical steroids alone: Insufficient for this severe form.

  • D. Topical salicylic acid: Insufficient as monotherapy for this condition.

28. Lichen planus is associated with:
C. Wickham striae.

• Explanation: Wickham striae are fine white lines seen on the surface of lichen planus lesions, typically in the oral mucosa or on the skin.

• Options explained:

  • A. Positive Auspitz sign: Seen in psoriasis, not lichen planus.

  • B. Apple jelly nodules: Seen in lupus vulgaris, not lichen planus.

  • D. Darier’s sign: Seen in mastocytosis, not lichen planus.

29. Pityriasis rosea is commonly associated with:
A. Herald patch.

• Explanation: A herald patch is the initial lesion in pityriasis rosea, followed by a secondary rash often distributed in a "Christmas tree pattern."

• Options explained:

  • B. Wickham striae: Seen in lichen planus, not pityriasis rosea.

  • C. Guttate lesions: Seen in guttate psoriasis, not pityriasis rosea.

  • D. Nikolsky sign: Seen in pemphigus vulgaris and TEN, not pityriasis rosea.

30. Lichen planus is characterized by:
D. Purple, pruritic, polygonal papules.

• Explanation: The classic description of lichen planus lesions is purple, pruritic (itchy), polygonal (shape), and papular (raised).

• Options explained:

  • A. Red scaly lesions: More typical of psoriasis.

  • B. Erythematous vesicles: Seen in eczema or dermatitis, not lichen planus.

  • C. Bullous lesions: Not characteristic of lichen planus.

31. The primary treatment for seborrheic dermatitis is:
B. Ketoconazole shampoo.

• Explanation: Ketoconazole shampoo is the treatment of choice for seborrheic dermatitis as it targets the Malassezia yeast, which plays a key role in the condition.

• Options explained:

  • A. Coal tar shampoo: An older option with limited efficacy compared to antifungal treatments.

  • C. Salicylic acid shampoo: Helpful for scaling but not as effective in addressing the underlying cause.

  • D. Antibiotic ointment: Irrelevant, as seborrheic dermatitis is not primarily bacterial.

32. Auspitz sign is characteristic of:
A. Psoriasis.

• Explanation: Auspitz sign refers to pinpoint bleeding observed when psoriatic scales are removed. It is highly characteristic of psoriasis.

• Options explained:

  • B. Lichen planus: Does not present with Auspitz sign.

  • C. Pemphigus vulgaris: Associated with Nikolsky’s sign but not Auspitz sign.

  • D. Eczema: Does not exhibit Auspitz sign.

33. A common trigger for guttate psoriasis is:
C. Streptococcal throat infection.

• Explanation: Guttate psoriasis is often triggered by streptococcal infections, particularly pharyngitis or tonsillitis.

• Options explained:

  • A. Malassezia infection: Associated with seborrheic dermatitis, not guttate psoriasis.

  • B. Viral exanthem: Incorrect; guttate psoriasis is not triggered by viral rashes.

  • D. Mycobacterial infection: Seen in lupus vulgaris, not guttate psoriasis.

34. The treatment of choice for erythema nodosum is:
B. Treat the underlying cause.

• Explanation: Erythema nodosum is a reactive condition; addressing the underlying cause (e.g., infection, drug reaction) is key to resolution.

• Options explained:

  • A. Corticosteroids: Used in severe cases but not the primary treatment.

  • C. Antifungal therapy: Irrelevant unless the underlying cause is fungal.

  • D. Antibiotics: Used only if the underlying cause is bacterial.

35. Nail pitting is commonly seen in:
A. Psoriasis.

• Explanation: Nail pitting, onycholysis, and discoloration are hallmarks of nail involvement in psoriasis.

• Options explained:

  • B. Lichen planus: Causes nail thinning and ridging, not pitting.

  • C. Alopecia areata: Can cause nail changes like ridging but not pitting.

  • D. Eczema: Does not typically cause nail pitting.

36. The most characteristic feature of pemphigus vulgaris is:
C. Intraepidermal blistering.

• Explanation: Pemphigus vulgaris is an autoimmune disorder characterized by intraepidermal blistering due to autoantibodies targeting desmogleins.

• Options explained:

  • A. Subepidermal blistering: Seen in bullous pemphigoid, not pemphigus vulgaris.

  • B. Granulomatous inflammation: Not seen in pemphigus vulgaris.

  • D. Spongiosis: Seen in eczema, not pemphigus vulgaris.

37. A herald patch is most commonly associated with:
A. Pityriasis rosea.

• Explanation: A herald patch is a single large lesion that appears days before the secondary eruption in pityriasis rosea.

• Options explained:

  • B. Psoriasis: Does not present with a herald patch.

  • C. Lichen planus: Does not have a herald patch.

  • D. Seborrheic dermatitis: Unrelated to herald patches.

38. Wickham striae are a feature of:
B. Lichen planus.

• Explanation: Wickham striae are fine white lines or reticulations seen on the surface of lichen planus lesions, especially in the oral mucosa.

• Options explained:

  • A. Psoriasis: Does not exhibit Wickham striae.

  • C. Pityriasis rosea: Does not show Wickham striae.

  • D. Eczema: Unrelated to Wickham striae.

39. The most common site for seborrheic dermatitis is:
C. Scalp.

• Explanation: The scalp is the most commonly affected area in seborrheic dermatitis, presenting with dandruff or greasy scaling.

• Options explained:

  • A. Hands: Uncommon site for seborrheic dermatitis.

  • B. Elbows: More common for psoriasis (extensor surfaces).

  • D. Palms: Rarely involved in seborrheic dermatitis.

40. Which of the following is a premalignant condition?:
D. Actinic keratosis.

• Explanation: Actinic keratosis is a premalignant lesion that can progress to squamous cell carcinoma if untreated.

• Options explained:

  • A. Seborrheic keratosis: Benign and not premalignant.

  • B. Erythema multiforme: Reactive condition, not premalignant.

  • C. Psoriasis: A chronic inflammatory condition, not premalignant.