Functions of the Skin Correct Answer: - First line of defense.
- Prevents excessive fluid loss.
- Control of body temperature.
- Sensory perception
- Synthesis of Vitamin D
Types of Skin Lesions Correct Answer: - Location
- Length of time it has been present
- Changes occurring over time
- Physical appearance
- Presence of pain or pruritus (itching)
Common Skin Lesion - Macule Correct Answer: - small, flat, circumscribed, different color than
skin
Common Skin Lesion - Nodule Correct Answer: - firm, raised, deep, varies in size
Common Skin Lesion - Papule Correct Answer: -small, firm, elevated
Common Skin Lesion - Pustule Correct Answer: - raised, often with a head, filled with exudate
or pus
Common Skin Lesion - Vesicle Correct Answer: - blister, thin wall, raised, fluid filled
Common Skin Lesion - Plaque Correct Answer: - slightly elevated, flat, scale like
Common Skin Lesion - Ulcer Correct Answer: - cavity with loss of tissue, often weeping or
bleeding
Common Skin Lesion - Fissure Correct Answer: - small, deep, crack in tissue
Common Skin Lesion - Crust Correct Answer: - dry, rough surface, dried exudate or blood
Common Skin Lesion - Lichenification Correct Answer: - thick, dry, rough surface (leather like)
Common Skin Lesion - Keloid Correct Answer: - raised, irregular, increasing mass of collagen
resulting from excessive scar tissue
Common Skin Lesion - Erosion Correct Answer: - shallow, moist cavity in epidermis
Common Skin Lesion - Comedone Correct Answer: - mass of sebum, keratin, and debris
blocking the opening of a hair follicle.
,Pruritus Correct Answer: - Associated with: allergic responses, chemical irritation caused by
insect bites, infestations by parasites (ex. scabies).
-Mechanism not totally understood: release of histamine in a hypersensitivity; infection may
result from breaking the skin barrier; caused by scratching
- Treatment includes topical agents to reduce sensation; treated by antihistamines or
glucocorticoids
Diagnostic Tests for Skin Lesions - Culture and staining of specimens Correct Answer: -
bacterial infections: microscopic and direct observations
-specific procedures for fungal or parasitic infections
Diagnostic Tests for Skin Lesions - Biopsy Correct Answer: - detection of malignant changes
- safeguard prior to or following removal of skin lesions
Diagnostic Tests for Skin Lesions - Blood tests Correct Answer: - helpful in diagnosis of
conditions caused by allergy or abnormal immune reaction
Diagnostic Tests for Skin Lesions - Skin Testing Correct Answer: - using patch or scratch
method
Contact Dermatitis Correct Answer: - exposure to an allergen (metals, cosmetics, soaps,
chemicals, plants; sensitization occurs on first exposure; pruritic rash develops at site a few hours
after exposure)
- direct chemical or mechanical irritation (doesn't involve immune response; inflammatory
because of direct exposure; removal of irritant; reduction of inflammation with topical
glucocorticoids)
Urticaria (Hives) Correct Answer: - Result of type I hypersensitivity (ingestion of substances
like shellfish, drugs, certain fruits)
-Lesions are highly pruritic
-Hives are often part of anaphylaxis (check for swelling around mouth and check airway;
administer EpiPen or other first aid)
Atopic Dermatitis (Eczema) Correct Answer: Atopic—inherited tendency
- Common problem in infancy (Rash is erythematous, with serous exudate. Commonly occurs on
face, chest, and shoulders )
- In adults, rash is dry, scaly, and pruritic, often on flexor surfaces.
, - Chronic inflammation results from response to allergens. (Eosinophilia and increased serum
IgE levels)
- Potential complication—secondary infections
- Treatment is topical glucocorticoids & antihistamines
Psoriasis Correct Answer: - Chronic inflammatory skin disorder (silvery patches)
-Results from abnormal T cell activation (excessive proliferation of keratinocytes; cellular
proliferation is greatly increased)
- Lesions found on face, scalp, elbows, knees (itching or burning sensations)
Treatment is glucocorticoids, tar preparations, antimetabolites
Scleroderma Correct Answer: - Occurs as skin disorder and/or may be systemic and affect
viscera
-Primary cause is unknown (increased collagen deposition is observed in all cases; inflammation
and fibrosis with decreased capillary networks; hard, shiny, tight, immovable areas of skin;
impaired movement of mouth and eyes)
- May cause renal failure, intestinal obstruction, respiratory failure caused by distortion of tissues
Skin Infections Correct Answer: - Caused by bacteria, viruses, fungi and others.
- Opportunistic microbes
- Minor abrasion or cuts
- Serious infections can develop
- Causative organisms need to be identified for appropriate treatment
Cellulitis (Erysipelas) Correct Answer: - Infection of the dermis and subcutaneous tissue
- Usually secondary to an injury
-Iatrogenic
- Causative organism (usually S. aureus or Streptococcus)
-Frequently in lower trunks and legs (red, swollen, painful, red streaks running along lymph
vessels proximal to infected area)