CLIN PATH: EXAM #2 (DERM LEC CCs)

Pt presents with keratin hyperplasia & proliferating cells in the stratum basale + stratum spinosum due to T cell activation & cytokine release. This causes greater epidermal thickness & accelerated epidermis turnover. What Dx has this typical pathophys?

Psoriasis

Pt presents with plaques (M/C) that are raised, well-demarcated, pink-red plaques or papules with thick silvery white scales. M/C on the extensor surfaces of the elbows/knees, scalp, & nape of the neck. Usually pruritic. What Dz do you suspect?

Psoriasis

___________________:

• Vacuoles appear in the lower epidermis

• Colloid bodies are also present

• Mature lesions are composed of CD8 cytotoxic T cells

Lichen Planus

PE for ___________________:

- 6 p's: purple, polygonal, planar, pruritic, papules or plaques with fine scales & irregular borders that may also have Wickham striae (fine white lines on the skin lesions or on the oral mucosa). May also develop Koebner's phenomenon (new lesions at sites of trauma - also seen in psoriasis). Nail dystrophy. May cause scarring alopecia.

Lichen Planus

______________: fine white lines on the skin lesions or on the oral mucosa. Characteristic in Lichen Planus.

Wickham striae

Common sites of _________________:

•Flexor surfaces of the extremities

•Genital skin

•Mucous membranes

Lichen Planus

This Dz is characterized by "target lesions" consisting of three components: a monomorphous pattern of dusky, central area or blister, a dark red inflammatory zone surrounded by a pale ring of edema, and an erythematous halo on the extreme periphery of the lesion. M/C on acral surfaces (extremities and trunk).

Erythematous Multiforme

This Dz clinically manifests as a negative Nikolsky sign (no epidermal attachment).

Erythematous Multiforme

In __________________ "target lesions" distributed acrally with no mucosal membrane involvement.

Erythematous Multiforme (Minor)

In _______________________ "target lesions" acrally progressing centrally + mucosal membrane involvement (oral, genital, or ocular). No epidermal detachment.

Erythematous Multiforme (Major)

In Erythematous Multiforme, a sparse inflammatory infiltrate = _____________________.

keratinocyte necrosis

In Erythematous Multiforme, the target-like appearance reflects what?

Zones of inflammatory rxn and damage(middlepartdiesoff)

Erythematous Multiforme MAJOR encompasses:

• ____________________:

• Profound mucosal involvement +/- cutaneous lesions

Stevens-Johnson syndrome

Erythematous Multiforme MAJOR encompasses:

____________________:

• Cause - idiosyncratic drug rxn

• Large areas of skin & mucosa become necrotic with secondary vesiculation

Toxic epidermal necrolysis

______________ is a autoimmune disorder leading to blister formation & severe pruritus. Primarily seen in the elderly. It is a Type II hypersensitivity rxn - IgG autoantibodies against hemidesmosomes & basement membrane zone causing subepidermal blistering.

Bullous pemphigoid

This Dz clinically manifests as a prodrome of pruritus with eczematous or urticarial plaques followed by tense large bullae that don't rupture as easily most commonly involving the groin, axilla, trunk, & flexural areas. Blister roof contains epidermis.

Bullous pemphigoid

Life-threatening, chronic autoimmune blistering disorder of the mucous membranes and skin. Type II hypersensitivity rxn where autoantibodies (IgG) agains desmoglein, a component of the desmosome, lead to acantholysis (separation of the dermis).

Pemphigus vulgaris

__________________ is a disease of the skin and mucous membranes only

Bullous pemphigoid

______________: Inflammatory disorder affecting small blood vessels of the skin --> eruption of reddish or violaceous papules, a pattern known as palpable purpura.

Leuokocytoclastic Vasculitis

________________: Lesions develop in crops --> indiv lesions persist a few days, less than 1 month

Leuokocytoclastic Vasculitis

Pt presents with palpable purpura post-streptococcal infection x 3 days. What Dz do you suspect?

Leuokocytoclastic Vasculitis

Histopath/Pathogen of Leuokocytoclastic Vasculitis: Inflammatory reaction involving blood vessels in association with an accumulation of ______________________

necrotic nuclear (leukocytoclastic) debris

The erythematous or purpuric quality of ___________________ --> numerous erythrocytes that accumulate in the dermis of fully developed lesions.

Leukocytoclastic Vasculitis

Leukocytoclastic Vasculitis can develop at any site, but mainly _________________.

lower extremities

In Leukocytoclastic Vasculitis, _____________ (M/C), can also be vesicopustules, necrotic papules and ulcers

purpuric lesions

Spongiotic Dermatitis pattern example: ___________________

Allergic Contact Dermatitis

Vesiculobullous Dermatitis pattern example: ________________

Bullous pemphigoid

Vasculitis pattern example: _________________________

Leuokocytoclastic Vasculitis

___________________: nickel (M/C worldwide), poison ivy, oak or sumac; other metals, chemicals (eg, fragrances, glue, hair dyes), detergents, cleaners, acids, prolonged water exposure.

Allergic Contact Dermatitis

_____________________: Type IV hypersensitivity rxn (T-cell mediated - delayed by days.)

Allergic Contact Dermatitis

Pt presents with erythematous papules or vesicles (may be linear or geometric). Often associated with localized pruritus, stinging, or burning. May ooze, develop edema, & progress to blisters or bullae/vesicles.

Allergic Contact Dermatitis

The term “______________” refers to edema of the epidermis, which separates keratinocytes from one another

spongiosis

Spongiotic dermatitis is accompanied by a variable amount of ________________.

perivascular inflammation

In Spongiotic dermatitis, the infiltrate is typically composed of ______________, but eosinophils are often concurrently

lymphocytes

In Allergic Contact Dermatitis, first exposure may not yield a rxn but the pt is now _________________.

sensitized

Type IV Hypersensitivity _______________: allergen binds to endogenous protein --> creation of foreign protein

Induction phase

Type IV Hypersensitivity Induction Phase:

__________________ engulf the complex, partially degrade it, migrate to lymph nodes & present antigenic fragments on cell surfaces with MHC-II molecules --> allergen complex --> T cell receptors bind with the allergen complex --> T cells clone themselves.

Langerhans' cells

Type IV Hypersensitivity Induction Phase:

Langerhans’ cells engulf the complex, partially degrade it, migrate to lymph nodes & _________________" --> allergen complex --> T cell receptors bind with the allergen complex --> T cells clone themselves.

present antigenic fragments on cell surfaces with MHC-II molecules

Type IV Hypersensitivity Induction Phase:

Langerhans’ cells engulf the complex, partially degrade it, migrate to lymph nodes & present antigenic fragments on cell surfaces with MHC-II molecules --> allergen complex --> ______________________ with the allergen complex --> T cells clone themselves.

T cell receptors bind

Type IV Hypersensitivity Induction Phase:

Langerhans’ cells engulf the complex, partially degrade it, migrate to lymph nodes & present antigenic fragments on cell surfaces with MHC-II molecules --> allergen complex --> T cell receptors bind with the allergen complex --> _____________________.

T cells clone themselves.

Type IV Hypersensitivity: Elicitation phase

Antigen appears again --> ___________________ process the antigen & migrate to lymph nodes --> T cell presentation also occurs at the site of contact - because now they are recognized --> Inflammatory cytokines create an amplification loop --> clinically recognized dermatitis

Langerhans' cells

Type IV Hypersensitivity: Elicitation phase

Antigen appears again --> Langerhans’ cells process the antigen & migrate to lymph nodes --> _______________________ because now they are recognized --> Inflammatory cytokines create an amplification loop --> clinically recognized dermatitis

T cell presentation also occurs at the site of contact

Type IV Hypersensitivity: Elicitation phase

Antigen appears again --> Langerhans’ cells process the antigen & migrate to lymph nodes --> T cell presentation also occurs at the site of contact - because now they are recognized --> _______________________ --> clinically recognized dermatitis

Inflammatory cytokines create an amplification loop

Type IV Hypersensitivity: Elicitation phase

Antigen appears again --> Langerhans’ cells process the antigen & migrate to lymph nodes --> T cell presentation also occurs at the site of contact - because now they are recognized --> Inflammatory cytokines create an amplification loop --> _____________________

clinically recognized dermatitis

Common causes of ___________________:

- Rhus dermatitis – often appears linear

• Poison ivy

• Poison oak

• Nickel allergy

• Soaps and detergents

Allergic Contact Dermatitis

Panniculitis pattern (inflammation of the fat layer below the skin) example: ________________________

Erythema Nodosum

What is the M/C form of panniculitis?

Erythema Nodosum

Pt presents with painful, erythematous, inflammatory nodules seen on the B/L anterior shins (range in colors from pink, red to purple.) Pt had a streptococcal infection and coccidioidomycosis (fungal) 1 month ago. They also have Sarcoidosis and take OCPs (estrogen exposure). What Dz do you suspect?

Erythema Nodosum

What disease happens in Women > men (3:1) with an etiology: end result of inflammation, infection, Strep pharyngitis, Meds, sulfonamides, Hormones (including pregnancy), OCs containing estrogen, Inflammatory bowel disease (IBD)

Erythema Nodosum

Panniculitis pattern: Erythema Nodosum

- Inflammation occurs in septal divisions btwn _____ compartments

fat

Panniculitis pattern: Erythema Nodosum

• Infiltrate consists of _________________________________

lymphocytes, histiocytes, granulocytes (neutrophils & eosinophils)

Panniculitis pattern: Erythema Nodosum

• Septa thicken & can become ______________ depending upon the infiltrate & duration of rxn

fibrotic

Panniculitis pattern: Erythema Nodosum

• Fat necrosis often spreads to the sc lobules

• Can appear as ____________________ or small stellate clefts within the macrophages

foamy (lipid-laden) macrophages

Panniculitis pattern: Erythema Nodosum

• Immunologic: Believed to be a delayed-type (type IV) hypersensitivity rxn in the ________________

•May involve Immune complex deposition in septum

septal fat

Nodular dermatitis pattern: _____________________

Cutaneous Sarcoidosis

What nodular dermatitis often presents on the face with nodular granulomas that can occur in the pulmonary tree & other viscera?

Cutaneous Sarcoidosis

20 y/o AA Female presents with Granulomas (collections of tissue macrophages) are present in the dermis. PMHx includes: Löfgren’s syndrome, Lupus pernio, and TB (M tuberculosis).

Cutaneous Sarcoidosis

What Dz occurs when Antigens induce T cells --> cytokines --> recruit macrophages to the site?

Cutaneous Sarcoidosis

Nodular dermatitis pattern: Cutaneous Sarcoidosis

• _________________- limit the extent of response

CD8 suppressor cells

Nodular dermatitis pattern: Cutaneous Sarcoidosis

• _________________ direct the immune response

CD4 helper cells

CXR and bone radiographs with findings suggestive of ________________ or skin biopsy

sarcoidosis

Folliculitis and Perifolliculitis Pattern: __________

Acne

This Dz commonly presents as follicle-based comedones, inflammatory papules, or pustules on face, neck, chest and back

Acne

Disfiguring __________________ with severe scarring does not occur before puberty.

nodulocystic acne

Numerous inflamed pustules and papules with central black plugs --> _____________________

open comedones or "blackheads"

__________________ is manifest as a widened follicle with a dense keratin plug within its infundibulum

Comedonal acne

__________________ ("blackheads") --> follicular orifice is open. Incomplete blockage.

Open comedones

_________________ ("whiteheads") --> orifice is normal, and follicle is plugged below the skin surface. Complete blockage.

Closed comedones

Closed comedones ("whiteheads"): _______________ may accompany the keratinous plug with the follicular canal, creating a pustular lesion

Neutrophils

Inflammatory acne lesions are a consequence of follicles that have ruptured with resultant spillage of keratinous debris into the perifollicular dermis, evoking a dense inflammatory reaction with a mixture of _______________________.

neutrophils, lymphocytes, and histiocytes

4 components to develop acne lesions:

• Folliculosebaceous unit is plugged by keratin

• Sebum production

• Overgrowth of Cutibacterium (formerly Propionibacterium) acnes

• ______________________

Secondary inflammatory process

4 components to develop acne lesions:

• Folliculosebaceous unit is plugged by keratin

• Sebum production

• _____________________________

• Secondary inflammatory process

Overgrowth of Cutibacterium (formerly Propionibacterium) acnes

4 components to develop acne lesions:

• Folliculosebaceous unit is plugged by keratin

• ______________________

• Overgrowth of Cutibacterium (formerly Propionibacterium) acnes

• Secondary inflammatory process

Sebum production

4 components to develop acne lesions:

• ________________________

• Sebum production

• Overgrowth of Cutibacterium (formerly Propionibacterium) acnes

• Secondary inflammatory process

Folliculosebaceous unit is plugged by keratin

ACNE:

1. Keratinocytes becomes sticky & fail to slough -->________________

follicular plugging

ACNE:

2. Increased sebum within the follicle acts as a food source for C. acnes --> __________________

bacterial overgrowth

ACNE:

3. Sebum degrades to lipids & free fatty acids --> _______________________

expansion of follicular canal

ACNE:

4. C. acnes recruits neutrophils --> ____________________

pustule formation

ACNE:

5. Neutrophilic enzymes weaken the ___________________ --> releases large amounts of inflammatory reactants into dermis

follicle wall --> rupture

ACNE:

6. Lymphocytes, macrophages & neutrophils respond.

• The comedone is now transformed into: ____________________

Inflamed papule, Pustule, Nodule of acne

ACNE:

7. Follicular rupture & intense 2° rxn may create profound ___________

scarring

In what population does the following occur:

• Maternal androgens stimulate enlargement of sebaceous glands --> Increased sebum production

• Sebum promotes C. acnes overgrowth --> acne

Neonates

In what population does the following occur:

• Androgens stimulate enlargement of sebaceous glands" sebum production in face, neck, chest & back

• Onset may be gradual or rapid

Puberty

__________ clinical manifestations:

• Follicle based comedones, inflammatory papules, or pustules

• Widened follicle with dense keratin plug within its infundibulum

Acne

What two Dz can present as a component of Acne?

PCOS and SAPHO

What Acne classification?

- Few to several papules/pustules (generally < 10) and no nodules

Mild Acne

What Acne classification?

- Several to many papules/pustules (10 - 40) along with comedomes (10 - 40) and few to several nodules

Moderate Acne

What Acne classification?

- Numerous or extensive papules/pustules and many nodules

Severe Acne