3rd Midterm Study Guide: Dermal Pathology Flashcards
What are the 3 cell types of skin?
Squamous cells
Basal cells
melanocytes
Appendages of the skin include…
Apocrine = sweat milky with odors near hair follicles
Eccrine = widely distributed water sweat for heat
Sebaceous = secretes oily sebum for lubrication and to
prevent water loss.
What is a Macule?
Flat, circumscribed (< 5mm)
What is a Papule?
elevated dome or flat topped ( < 5 mm)
What is a Nodule?
elevated dome
> 5 mm
What is a plaque?
elevated flat topped lesion
> 5 mm
What is Lichenification?
Thickened skin due to repeated rubbing
What is a Pustule?
discrete, pus filled raised lesion
what is a Scale?
Dry, plate-like excrescence, imperfect cornification
What is a Vesicle?
Fluid filled raised area
< 5 mm
What is Acantholysis?
Loss of intracellular adhesion keratinocytes
epidermis falls apart and sloughs off
What is Excoriation?
traumatic breakage of the skin
result of intense scratching
What is a Bulla?
Fluid filled raised area
> 5 mm
What is dyskeratosis?
abnormal keratinization that is deeper in the epidermis than normal.
What is hyperkeratosis?
Hyperplasia of stratum cornum
What is spongiosis?
Intracellular edema of the epidermis
What is papillomatosis?
Surface elevation caused by hyperplasia
What are examples of acute inflammatory pathologies of the skin?
- Urticaria (hives)
- Eczematous Dermatitis
- Allergic Contact Dermatitis
- Erythema Multiforma
- Stevens-Johnson Syndrome
What is Urticaria?
Hives
- hypersensitivity mediated by antigens (IgE)
- treat with antihistamine or steroids
What is eczematous Dermatitis?
Contact Dermatitis most common
- delayed hypersensitivity that can be pruritic, edematous, or oozing plaques/vesicles.
- can also be caused by drugs, UV or chemicals
What is Allergic Contact Dermatitis?
Cellular memory of the reaction so that future contacts cause an increased dermatitis reaction
What is Erythema Multiforma?
Hypersensitivity to infections and drugs
- dermal edema that can have blisters or necrosis
- wide range of expressions and severity
What is Stevens-Johnson Syndrome?
A Generalized all over the the body reaction to medicines (Sulfonamides and Salicylates)
- Can also be a reaction to infections such as herpes or a fungus.
- advanced can have epidermal necrosis and blisters
- T-cells attacking antigen and surrounding cells (basal cells)
What are examples of chronic inflammatory pathologies of the skin?
- Psoriasis
- Lichen Planus
What is Psoriasis?
Either caused by:
- Inciting antigen
- auto-rejection
- environmentally induced
- Well marked with pink/salmon plaques
- regular acanthosis in epidermis (increased bleeding)
- Can be accompanied by increase in heart attacks and arthritis
*tx includes NSAIDS and immunosuppressants.
What is Lichen Planus?
Lace like white markings referred to as WICKAM STRIAE
on the extremities and oral cavity
-Hyperkeratosis and epidermal hyperplasia
-Resolves after 1-2 years although often stays in mouth
-seen in the middle aged with unknown inciting mechanisms. (Maybe hyperactive T cells?)
Infectious Dermatosis can be…
Bacterial
Fungal
Viral
What is Bacterial Infectious Dermatosis?
Impetigo from staph or strep
*tx with topical antibiotics like tetracycline
What is Fungal Infectious Dermatosis?
Tinea (ring worm) or Candidiasis
- pruritic, erythematous macules
- Very common in immunocompromised
What is Viral Infectious Dermatosis?
Wart Pathology (HPV and Verrucae) -Contagious by direct contact -can auto inoculate and spread Epidermal hyperplasia Papillo Mitosis
What is the prominent feature of Bulbous Blistering?
Pemphigus
painful flaccid blister-like deep erosions and crust after rupture - Hypersensitivity Rxn
What do you use to treat Dermatitis Herpetiformis?
Use Immunosuppressive treatment
What are the expressions of Herpes infections?
group vesicles
epidermal ancatholysis
Vesicles
Sloughing
What are Characteristics of V Zoster virus?
Unilateral dermatomal distribution
Expresses as a band of rash that often itches/burns/throb
May persist for weeks to months
Usually tx with anti-inflammatories or opioid analgesics
Not contagious, usually doesn’t repeat but can
What are characteristics of pemphigus?
Several Variants
- Acanthosis
- Blister Formation (Bullous)
- Autoimmune
- typically treat with steroids
What is acne?
Infected hair follicles
How is acne expressed?
Opened comodomes (blackheads)
Closed comodomes (whiteheads)
Cysts, pustules, accesses, scarring
Worsens with Drugs such as steroids, contraceptives, and testosterone
What is characteristic of Acne Vulgaris?
- Hormone changes (increased testosterone)
- Blocks hair follicle and sebaceous gland
- Hair follicle have proliferation of lining cells and cellular sloughing which forms a cellular plug and traps bacteria, debris and sebum
- Gland ruptures and contents spread forming Cysts, accesses, and scarring.
What are treatments for Acne Vulgaris?
- Antibiotics (Tetracycline)
- Keratolytics
- Drying agents
- Vitamin A (topical and systemic Accutane)
- UV exposure
What is characteristic of Perioral Dermatitis?
- Seen in Young Women
- Long-term steroid use of cosmetic use, hormonal change
- Follicular Papules, Vesicles, and pustules
What are 4 skin pathologies that are Neoplastic Benign?
- Seborrhea Keratosis
- Actinic Keratosis
- Melanocytic Nevi
- Dysplastic Nevi
What is characteristic of Seborrhea Keratosis?
- Elderly to Middle age
- Coin-like plaques
- Stuck-on appearance
- Tan to dark brown granular surface
- Can be spread generally
What is characteristic of Actinic Keratosis?
- Pre-Malignant, related to UV exposure in fair skinned
- Appears brown to red, rough scaly lesions
What is characteristic of Melanocytic Nevi (moles)?
- Benign Neoplasm from melanocytes
- Variable in appearance
- Well defined borders and not predisposed to cancer
What is characteristic of Dysplastic Nevi?
- Sporadic
- If greater than 10 lesions, increased risk for melanoma
- Irregular borders
- Asymmetric borders
Most common skin malignancies…
- Basal cell
- Squamous cell
- Melanoma
What is characteristic of a Basal cell malignancy?
- Most Common malignancy world wide
- Least aggressive
- Slow growing
What is characteristic of Squamous cell Malignancy?
- Next most common
- intermediate aggression, no metastasis
- Red scaling plaques-locally aggressive
What is characteristic of Melanoma?
- Least Common
- Typically aggressive and metastasizes
- Caused by UV exposure and genetics
- High mitotic rate and lack of immune response to slow spread, especially when it hits lymph nodes.
- Poor prognosis if metastasized (brain, lungs, liver)
What are the warning signs for a Melanoma?
- Rapid enlargement of Nevus
- New Pigmented lesion - not from preexisting nevi
- irregular borders
- irregular surface and colors
