Chapter 12 - Dermatology

Question 1

Integumentary System:

Skin

Answer 1

largest organ of the body

• protect the body against germs
• helps in the regulation of body temperature
• assists with the elimination of wastes through sweat
• epidermis = composed of keratinized, stratified, squamous epithelial tissue with 4 layers: stratum corneum, stratum granulosum, stratum spinosum, and stratum basale
• dermis = composed of strong, flexible connective tissue

Question 2

Integumentary System:

Sweat glands

Answer 2

located throughout the skin

• help to regulate body temperature and excrete wastes
• each coiled, tubular gland has a secretory portion that lies within the dermis and a duct that travels to the surface of the skin where it forms a funnel shaped pore

Question 3

Integumentary System:

Sebaceous (oil) glands

Answer 3

located in all areas of the skin except over the palms of hands and feet

• sebum = an oily substance secreted
• blockage of a gland duct leads to an accumulation of sebum, which causes a “whitehead” to form
• acne is caused by inflammation of the sebaceous glands and appears as pustules (pimples) and cysts on the skin

Question 4

Integumentary System:

Hair and Nails

Answer 4

• hair follicles extend from the dermis up to the epidermal surface
• folliculitis = infection of the hair follicle
• nails provide a protective covering for the dorsal aspect of the fingers and toes
• each nail consists of a free edge, body, and root
• the skin surrounding the nail forms the eponychium (cuticle) and proximal and lateral nail folds

Question 5

Repetitive Trauma:

Blisters

Answer 5

occur most frequently on soles of feet and palms of the hands

• appear as tender vesicles filled with either clear or serous fluid
• caused by combination of moisture and repetitive friction

Question 6

Repetitive Trauma:

Calluses

Answer 6

occur most often on the plantar surface of the foot or hand

- thickened areas of skin occur in response to repetitive friction

Question 7

Repetitive Trauma:

Acne Mechanica

Answer 7

typically presents as either papules or pustules in mild to moderate cases and may transition to cysts or nodules in more severe cases

• caused by combination of pressure, friction, heat, and occlusion
• occurs most often on forehead, chin, shoulders, and upper back
• treated with topical or systemic antibiotics like topical retinoids or benzoyl peroxide

Question 8

Repetitive Trauma:
Talon Noir (black heel)

Answer 8

associated with sports involving sudden stops and starts, like basketball and tennis

• lateral shearing forces cause intra-epidermal bleeding that presents as horizontally arranged rows of small dots along the posterior or post lateral heel
• also be seen on palms of hands from racket sports or weight-lifting
• paring down the superficial skin layers using a scalpel will remove the pigmented black heel

Question 9

Primary and Secondary Skin Infections

Answer 9

primary = involve an infectious agent entering and affecting normal skin

secondary = results from an infectious agent entering an existing break in the skin (cuts, laceration, other wounds)

risk factors = (1) warm, moist environment produced by perspiration and increased body temperature, (2) occlusive clothing and equipment, (3) close skin-to-skin contact, (4) acute and chronic trauma to skin

Question 10

Skin Infections:

Bacterial

Answer 10

classified into 1 of 3 categories:

1. contagious (impetigo)
2. continued competition can cause further tissue damage (cellulitis, furuncles, and carbuncles)
3. neither contagious or pose further risk to the patient (folliculitis)

Question 11

Bacterial Infections:

Staphylococcus aureus

Answer 11

present with small pimple-like lesions, pustules, or boils

• can attack existing cuts and abrasions
• easily spread to entire sports teams

Question 12

Bacterial Infections:

Impetigo

Answer 12

most commonly caused by the S aureus bacteria, some cases may involve the Group A Streptococcus (GAS) bacteria

• presents with honey-colored, crusted, well-defined, erythematous vesicles
• occurs most frequently on the face and other exposed areas

Question 13

Bacterial Infections:

Cellulitis and Erysipelas

Answer 13

acute bacterial infections involving the skin and subcutaneous tissues
- occur at the site of a previous wound (cut, laceration, bug bite)
- caused by either S.aureus or GAS
- present with redness, swelling, and warmth at the site of infection, and may include systemic symptoms like fever and malaise
- may look like the skin of an orange
- treated with antibiotics, and may in some cases require an incision to drain the abscess for full resolution
erysipelas = more superficial infection involving epidermis and upper portion of dermis with a raised, well-defined, expanding, red plaque
cellulitis = presents with a raised rede plaque, however will take several days to fully develop

Question 14

Bacterial Infections:

Folliculitis

Answer 14

gram-negative infection (S aureus) of the hair follicle most often caused by friction from clothing or equipment

• involve the superficial portion of the hair follicle, resolve on their own, and usually do not require treatment
• more extensive cases involve the deeper portion of the hair follicle and are associated with redness and tenderness

Question 15

Viral Infections

Answer 15

• spreading requires direct skin contact with infected lesions or their secretions
• prevention by covering all abrasions and other open wounds

Question 16

Viral Infections:

Herpes Simplex Virus

Answer 16

2 types:

• type 1 (HSV-1) = associated with herpes labialis and herpes gladiatorum
• type 2 (HSV-2) = associated with sexually transmitted genital herpes
• both can produce primary and secondary infections with primary more severe and produce systemic symptoms
• become dormant in neural ganglia, leading to periodic recurrences (shorter duration and less severe symptoms)

Question 17

Viral Infections:
Herpes Labialis (cold sore or fever blisters)

Answer 17

caused by HSV-1 and can present as a single vehicle or cluster of vesicles on the lips

• exposure to the sun and physical or emotional stress triggers for the development
• usually report prodomal symptoms of tingling or burning prior to appearance of lesions

Question 18

Viral Infections:

Herpes Gladiatorum

Answer 18

commonly affects wrestlers

• presents with clustered vesicular lesions on an erythematous base
• itching or burning in the area of the lesions prior to the actual appearance of the vesicles
• head, face, and extremities are most common sites affected as well as trunk and eyes

Question 19

Viral Infections:

Molluscum Contagiosum

Answer 19

spread through direct skin contact or sexual contact (STD)

• presents with a rash that includes white, pinkish, or skin-colored, dome-shaped papules with a center dimple
• definitive diagnosis made through histology or through a Molluscum preparation

Question 20

Viral Infections:

Warts

Answer 20

caused by HPV

• contagious and are spread by either skin-to-skin contact or contact with a contaminated surface
• treatment focuses on destroying the lesions by freezing, burning, electrocautery, or applying topical acids

Question 21

Viral Infections:

Plantar Warts

Answer 21

found on the soles of the feet

• commonly occur within calluses, where they hide the usual swirls or “fingerprints” of the callus
• grow into the foot rather than growing above the skin surface

Question 22

Fungal Infections

Answer 22

most common type of dermatological infections in athletes

• caused by dermatophytes and named for the sites they attack: tinea capitis (scalp), tinea barbae (beard area), tinea pedis (feet), tinea manum (hands), tinea cruris (groin area), tinea unguium (fingernails and toenails, tinea corporis. (all other skin areas)
• warm, moist environment serves as the primary predisposing factor

Question 23

Fungal Infections:
Tinea Pedis (feet)

Answer 23

• interdigital tinea pedis = first and most common form, occurs in web spaces of the toes and presents with a scaly, peeling area that may also be erythematous, with mace ration and fissuring
• second form = presents with vesicles or bullae on the mid foot
• third form = involves hyperkeratonic scale on the plantar surface of the foot

Question 24

Fungal Infections:
Tinea Cruris (jock itch)

Answer 24

caused by T rubrum or T mentagroohytes

• involves the proximal medial thighs, inguinal folds of the groin, and buttocks
• present with large, round, scaly plaques that have pustules and papules at the edges
• tight clothing, obesity, and chronic corticosteroid use are associated risk factors

Question 25

Fungal Infections: | Tinea Unguium

Answer 25

caused by T rubrum - affects the fingernails and toenails - distal subungual onychomycosis is most common form of nail fungus and appears white, hyperkeratotic patch under the nail - nail will become thickened and discolored and will eventually separate from the nail bed - does not respond well with topical anti fungal

Question 26

``` Fungal Infections: Tinea Corporis (all other skin areas) ```

Answer 26

caused by T rubrum dermatophyte and often referred as tinea gladiatorum - presents with a circular, erythematous, pruritic (itchy) plaque, with a raised edge, scaling, and central clearing

Question 27

Fungal Infections: | Tinea Versicolor

Answer 27

superficial fungal infection caused by Malassezia furfur organism - presents with macules or patches that have either a hypopigmented or hyper-pigmented appearance and may also include a dust-like scale - produces variations in skin color from white to red to brown - not contagious

Question 28

Parasitic Infections: | Scabies

Answer 28

contagious parasitic infection caused by Sarcoptes scabiei - spread through direct skin contact - most commonly affected sites are the fingers and toe webs, flexor surfaces of the wrists, elbows, axillae, buttocks, breasts, and male genitalia - after transfer from host, a pregnant mite will burrow into the epidermis to lay eggs - initially, a vesicles or papule may develop leading the severe itching symptom

Question 29

Parasitic Infections: | Pediculosis

Answer 29

parasite infestation with lice - most common affected sites are head (pediculus capitis), body (pediculus corporis), and genital area (pediculus pubis) - newly hatched lice begin biting and cause small red papules and itching

Question 30

Inflammatory Skin Conditions: | Acne Vulgaris

Answer 30

involves the sebaceous glands and hair follicles | - presents as “blackheads” and pimples (pustules) that may progress to erythematous macules, papules, and cysts

Question 31

Inflammatory Skin Conditions: | Contact Dermatitis

Answer 31

caused by exposure to or contact with a specific allergen ex: expose to poison ivy creating a rash - common symptoms include itching, erythema, wet and weeping skin

Question 32

Inflammatory Skin Conditions: | Chronic Eczema

Answer 32

present with slightly different symptoms than acute cases | - associated with dry skin, thickening of the epidermis, and fissure or cracks in the skin

Question 33

Inflammatory Skin Conditions: | Psoriasis (plaque)

Answer 33

commonly found on the extensor surfaces of the body (knees, elbows, knuckles) - T cell mediated disorder activates cascade of inflammatory processes that lead to rapid growth of epidermal and vascular cells - appear as symmetrical, round, erythematous plaques with silver-colored scales

Question 34

Environmental Skin Conditions: | Cold Urticaria

Answer 34

caused by exposure to cold - commonly associated with application of therapeutic modalities such as ice massage, ice bags, or ice slush baths - common symptoms include hives and itching

Question 35

Inflammatory Skin Conditions: | Frostnip

Answer 35

superficial skin injury caused by extended exposure to cold temperatures - most commonly affects the exposed skin areas like face, nose, chin, and ears - produces transient blanching, numbness, throbbing or burning, and a blue-white tint to the affected area

Question 36

Inflammatory Skin Conditions: | Frostbite

Answer 36

involves deeper tissues and can lead to damage of the subcutaneous tissue, muscle, and bone, which can also lead to limb loss - occurs as ice crystals in extra cellular space - skin appears waxy, dry, or cyanotic, and becomes hardened over the joints - ice in the tissues draws fluid from the cells, causing permanent damage to epithelial cells no blood vessels - once blood supply is disrupted, hypoxia necrosis occurs unless blood can be delivered through adjacent vessels - continued exposure progresses to deep frostbite, involving freezing in the deep layers of skin and possibly muscle or underlying tissues - during rewarming, intense pain, bright erythema, edema, and eventually blistering occur as blood supply returns - area should not be re-thawed if re-freezing is a possibility since it can increase the extent of tissue damage

Question 37

Inflammatory Skin Conditions: | Sunburn

Answer 37

extended exposure to UV rays, particularly peak times of 10am to 2pm - degree of skin injury can vary based on a variety of factors, like total time of exposure, altitude, and fairness of the skin - 1st degree burns = produce erythema - 2nd degree burns = erythema and blistering - 3rd degree burns = erythema, blistering, and ulcerations

Question 38

Inflammatory Skin Conditions: | Skin Cancer

Answer 38

most common form of all cancers - nonmelanoma = occur most often, involve the basal and squamous cells of the epidermis - basal cell cancers = develop on skin areas that have the greatest sun exposure (head and neck) but does not spread to other parts of the body - squamous cell carcinoma = 2nd leading form, occurs most frequently on areas with greatest sun exposure, and grows faster and more likely to spread to other parts of the body - melanoma = occurs in the lower epidermis and is formed from melanocytes, can spread to other parts of the body - typically brown or black, but also can be pink, red, or white

Question 39

Inflammatory Skin Conditions: Skin Cancer Risk Factors

Answer 39

2 types of UV rays: UVA and UVB - both types can damage DNA of skin cells - UV index reported on a scale from 1 to 11+ describes the intensity of UV rays reaching the ground around the time period of noon - the higher the UV index, the more damaging the UV rays