Integumentary

Question 1

Principles of Derm Assessment: What would you do in the following situations?
1. If patient is otherwise well without systemic symptoms and other signs?
2. If the patient is miserable (highly symptomatic) but not systemically ill (without additional signs and symptoms)?
3. If the patient is systemically ill with constitutional s/s (fever, fatigue, loss of appetite, unintended weight loss, malaise, and/or others)?
4. What should you consider when presenting with a condition?
5. How would you assess if there are primary lesions only? What about primary and secondary lesions?

Answer 1

1. When otherwise well, likely condition limited to the skin w/ few to minor symptoms (rosacea, keratosis pilaris [chicken skin at back of arm], seborrheic dermatitis)
2. When miserable but not systemically ill, often uncomfortable with itch, burning, pain, or the like, such as scabies, herpes zoster (shingles), others
3. When systemically ill with constitutional s/s, often has the dermatologic manifestation of a systemic ds, such as varicella, transepidermal necrosis, Lyme disease, systemic Lupus erythematosus, others
4. Consider which pts (age, gender, ethnicity, risk factors, etc) are at greatest risk for the condition; ex: acne vulgaris more common in teens, young adults vs rosacea more common in adults age 30-60 years, though facial lesions are similar
5. Where is the oldest lesion, and when did it occur? Where is the newest lesion, and when did it occur? This allows the examiner to assess the evolution of the skin lesions

Question 2

Anaphylaxis
1. Definition
2. Causes
3. Symptoms
4. Treatment

Answer 2

1. A severe, life-threatening hypersensitivity reaction; caused by immunoglobulin E (IgE)-mediated reaction to foods, insect stings, and drugs
2. Main causes in outpt: food allergies
3. • acute onset (minutes to several hours)
     - flushing
     - hives
     - angioedema
     - dyspnea
     - wheezing
     - tachycardia or bradycardia
     - hypotension
     - hypoxia
     - cardiac arrest
4. • IMMEDIATE tx w/ epinephrine (1mg/mL) 0.3-0.5 IM on mid-outer tight.
     - Repeat Q5-15 minutes PRN
     - In anaphylaxis, there are NO absolute contraindications to epinephrine.
     - CALL 911!

Question 3

Rocky Mountain Spotted Fever (RMSF)
1. Definition/Population/Incidence/Etiology
2. Clinical presentation
3. Lab/Diagnostics
4. Treatment

Answer 3

1. Most cases occur from April-Sept (spr-sum) in males, Native Americans, and ≥ 40 years
   - Highest mortality if not treated during first 5 days.
   - >60% occur in 5 states (NC, OK, AL, TN, MO)
2. • *Abrupt onset of high fever
     - chills
     - severe headache
     - nausea/vomiting
     - photophobia
     - myalgia
     - arthralgia
     → followed by rash, erupts 2-5 days after onset of fever (rash: small red spots [petechiae] starting on wrist, forearms, and ankles [sometimes on palms and soles] then rapidly onto trunk until it generalizes); ~10% do not develop rash
3. Clinical diagnosis
4. First line: doxycycline (both children & adults)
   - Use DEET-containing repellent on skin and permethrin on clothing

Question 4

Description: Impetigo

Answer 4

“honey-colored” crusts, fragile bullae, pruritic

Question 5

Description: Measles

Answer 5

Koplik’s spots are small, white, round spots on a red base on the buccal mucosa by the rear molars and appear 2-3 days before onset of symptoms

Question 6

Description: Scabies

Answer 6

• Very pruritic, especially at night
• Serpiginous rash on interdigital webs, waist, axilla, penis

Question 7

Description: Scarlet Fever

Answer 7

“Sandpaper” rash with sore throat (strep throat)

Question 8

Description: Tinea versicolor

Answer 8

• Hypopigmented round-to-oval macular rashes, most lesions on upper shoulders/back
• not pruritic

Question 9

Description: Pityriasis rosacea

Answer 9

• “Christmas tree” pattern rash (rash on cleavage lines)
• “herald patch” largest lesion, appears initially

Question 10

Description: Molluscum contagiosum

Answer 10

Smooth papules 2-5 mm in size that are dome-shaped with central umbilication with a white “plug”

Question 11

Description: Erythema migrans

Answer 11

• Red target-line lesions that grow in size
• Some central clearing
• early stage of Lyme disease

Question 12

Description: Meningococcemia (rash)

Answer 12

• Purple to dark-red painful skin lesions all over body
• acute onset of high fever
• headache
• LOC changes
• rifampin prophylaxis for close contacts
  **Life-threatening and CDC-reportable diseadse

Question 13

Description: rocky Mountain Spotted fever

Answer 13

AKA: Rickettsia rickettsii from tick bite
- red spot-like rash that first break out on the hand, palm, wrist and foot, sole, ankle
- acute-onset high fever
- severe headache
- myalgias

Question 14

Description: Brown recluse spider bite

Answer 14

• Bite area becomes swollen, tender, and red
• blisters appears within 24 hours
• center of lesion may form a purple-to-black eschar (10%), which becomes an ulcer when it sloughs up

Question 15

Brown Recluse Spider Bites
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostic
4. Treatment

Answer 15

1. Loxoscele reclusa – midwestern and southeastern US
   - Deaths are rare but has occurred in <7 years → any child with systemic signs → hospitalization (condition may cause hemolysis)
2. • fever
     - chills
     - nausea/vomiting
     - mostly located on arms, upper legs, or trunk (underneath clothing)
     - bite may feel like a pinprick (or painless)
     - bite area becomes swollen, red, and tender
     - blister appears 24-48 hours
     - central area of bite becomes necrotic (purple-black eschar); when eschar sloughs off → ulcer, which takes severe weeks to heal

Question 16

Erythema Migrans (early Lyme disease)
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostic
4. Treatment

Answer 16

1. early Lyme disease rash
   - Found most common in northeastern region of US
2. • Classic lesion: expending red rash with central clearing, resembling a target; the “bull’s-eye” or target rash; appears within 7-14 days after a deer bite (range 3-30 days)
     - rash feels hot to touch & rough texture
     - common locations: belt line, axillary area, behind knees, and groin
     - flu-like symptoms
     - Lesion spontaneously resolves within a few weeks
3. Clinical diagnosis with Lyme ds workup
4. • DEET containing repellent on skin and permethrin on clothing and gear

Question 17

Meningococcemia (Meningitis)
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostic
4. Treatment

Answer 17

1. Systemic infection caused by Neisseria meningitidis (gram-); progresses very rapidly → death in several hours
   * Fulminant cases → death in 48 hours
   Morality rate: 13%; risk ↑ for those in close quarters like college students in dorms, nursery/day care, military barrack; asplenia, defective spleen (sickle cell anemia), HIV or complement immune system deficiencies, & infants (3m - 1y)
2. • sudden onset of sore throat
     - cough
     - fever
     - headache
     - stiff neck
     - photophobia
     - changes of LOC (drowsiness, lethargy to coma)
     - In some cases, abrupt onset of petechial (small red spots) to hemorrhagic rashes (pink to purple color) in the axillae, flanks, wrist and ankles (50-80%)
     - hypotension and shock
     - in 25%, cutaneous hemorrhage and DIC
3. • ↑ procalcitonin in bacterial meningitis
4. • CDC → vaccination esp for those at higher risk asap after exposure
     - Rifampin BID x2 days & ceftriaxone 250 mg IM x1 dose for close contacts

Question 18

Herpes Zoster Ophthalmicus
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostics
4. Treatment

Answer 18

Shingles Infection of the Trigeminal Nerve
1. sight-threatening condition caused by reactivation of the herpes zoster virus located on ophthalmic branch of the trigeminal nerve (CN V)
- more common in elderly patients

2. • sudden eruption of multiple vesicular lesions (which rupture into shallow ulcers with crust)
     - located on one side of scalp, forehead, and side/tip of nose (if herpetic rash is seen on tip of nose, assume shingles until proven otherwise)
     - ipsilateral eyelid swollen and red
     - photophobia
     - eye pain
     - blurred vision
3. Clinical diagnosis +/- cultures
4. Refer to ophthalmologist or ED asap

Question 19

Melanoma
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostics
4. Treatment

Answer 19

1. Type of skin cancer, high morality
   Risk Factor:
   - family hx of melanoma (~10%)
   - extensive/intense sunlight exposure
   - blistering sunburn in children
   - tanning beds
   - high nevus count/atypical nevus
   - light skin/eyes
2. • lesions can be anywhere, including retina
     - dark-colored moles with uneven texture
     - variegated colors
     - irregular borders with diameter ≥6 mm
     - may be pruritic
     - If in nail beds (subungual melanoma) → may be very aggressive

Question 20

Acral Lentiginous Melanoma
1. Definition/Etiology
2. Clinical Presentation

Answer 20

1. Most common type of melanoma in African Americans and Asians
   - subtype of melanoma <5%
2. • dark brown-to-black lesions are located on nail beds (subungual), palmar and plantar (sole of foot), and rarely the mucus membrane
     - Subungual melanomas look like longitudinal brown-to-black bands on the nail bed

Question 21

Basal Cell Carcinoma
1. Definition/Etiology
2. Clinical Presentation

Answer 21

1. More common in fair-skinned individuals with long-term daily sun exposure
   - RF: severe sunburns as a child
2. • Superficial form (30%) looks pearly or waxy skin lesions with atrophic or ulcerated center that does not heal
     - lesions can be white, light pink, brown, or flesh color
     - may bleed easily with mild trauma

Question 22

Actinic Keratosis
1. Definition/Etiology
2. Clinical Presentation

Answer 22

1. • High risk: light-colored skin, hair, and/or eyes
     - older-to-elderly fair-skinned adults
     - in some cases, may be a precancerous lesion for SCC
     - early childhood hx of severe sunburns
2. • numerous dry, round, and red-colored lesions with a rough texture that do not heal
     - lesions are slow-growing
     - most common locations: sun-exposed areas (e.g., cheek, nose, face, neck, arms, and back)

Question 23

Subungual Hematoma
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 23

1 & 2. Direct trauma to nail bed → pain and bleeding trapped between nail bed and fingernail/toenail
- if hematoma involves >25% of nail, high risk for permanent ischemic damage to nail matrix if blood is not drained

3. • draining (trephination) by straightening out one end of a steel paperclip or use 18h needle, heat it with a family until very hot → hot end pushed down gently (90º angle) until a 3-4 mm hole is burned on nail
     - Nail is pressed down gently until most or all of blood is drained or suctioned with a smaller needle
     - blood may continue draining for 24-36 hours

Question 24

Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TENs)
1. Definition/Etiology
2. Clinical Presentation

Answer 24

1. • SJS: less severe, involves <10% of body skin; mortality rate 10%
     - TEN: more severe, involves >30%, mortality rate 30%
     - Most common triggers:
     * medications (allopurinol, anticonvulsants [lamotrigine, carbamazepine, phenobarbital], sulfonamides, and oxicam NSAIDs)
     - RF: HIV infection (100x higher risk; 40x ↑ risk with trimethoprim-sulfamethoxazole), genetics, lupus, and malignancies
2. • lesions appear like a target (or “bull’s eye”)
     - multiple lesions erupting abruptly; can be hives, blisters (bullae), petechiae, purpura, necrosis, and sloughing of the epidermis
     - extensive mucosal surface involvement (eyes, nose, mouth, esophagus, and bronchial tree)
     - may have a prodrome of fever with flu-like symptoms 1-3 days prior to rash

Question 25

Normal Findings: Anatomy of the skin
1. How many layers do the skin have?

Answer 25

3 layers
1. epidermis
2. dermis
3. subcutaneous

Question 26

Components of the following skin layers:
2. Epidermis
3. Dermis
4. Subcutaneous layer
5. Apocrine glands
6. Eccrine glands

Answer 26

2. No blood vessels; get nourishment from dermis; consists of 2 layers:
   - top layer → keratinized cells (dead squamous epithelial cells)
   - bottom layer → melanocytes reside and vit D synthesis occurs
3. Consists of blood vessels, sebaceous glands, and hair follicles
4. Composed of fat, sweat glands, and hair follicles
5. Type of sweat gland located mainly in axilla and groin
6. Major sweat glands of the body; helps with heat dissipation and thermoregulation

Question 27

Skin Examination: Darker colored skin
1. Keep in mind what regarding the appearance of urticaria and wheals in darker-colored skin? What would you expect the appearance to be?
2. Skin conditions more common in African Americans?
3. What is the “barber’s itch?” What is the treatment?

Answer 27

1. • Urticaria and wheals can appear paler than surrounding skin (palpate for induration and warmth)
     - very dry, dark skin may appear ashy to gray in color (check arms and legs)
2. • keloids
     - hyperpigmentation
     - traction alopecia (d/t chronic tight hair braiding)
3. Pseudofolliculitis barbae aka “barber’s itch”
   - affects 60% of African American men
   - caused by inflammation from curly hair growing back into skin
   - Treatment: let beard hair grow for 3-4 weeks
   - Advise pt to avoid shaving beard hair too short and too close to the skin

Question 28

Vitamin D Synthesis
Who has a longer time synthesizing vitamin D? What can vitamin D deficiency cause in pregnancy?

Answer 28

People with darker skin needs longer periods of sun exposure to produce vitamin D. A deficiency in pregnancy → infantile rickets (brittle bones, skeletal abnormalities)

Question 29

Acral

Answer 29

Distal portions of the limbs (i.e., hand or feet [acral melanoma]

Question 30

Annular

Answer 30

ring-shaped (ringworm or tinea corporis)

Question 31

Exanthem

Answer 31

cutaneous rash

Question 32

Extensor

Answer 32

The skin area that is outside of the joint (e.g., front of knee, back of elbow)

Question 33

Flexor

Answer 33

The area of skin on top of the join with skin folds (e.g., back of knees, antecubital space)

Question 34

Flexural

Answer 34

Skin flexures are body folds (eczema affects flexural folds)

Question 35

Intertriginous

Answer 35

An area where two skin areas touch or rub each other (e.g., axilla, breast skin folds, anogenital area, between the fingers/digits)

Question 36

Maculopapular rash

Answer 36

rash with color (usually pink to red) with small bumps that are raised above the skin (viral rash)

Question 37

Morbilliform

Answer 37

Rash that resembles measles (pink rash with texture)

Question 38

Nummular

Answer 38

coin-shaped, round (nummular eczema)

Question 39

purpura

Answer 39

bleeding into the skin; small bleeds are petechial (RMSF); and larger areas of bleeding are ecchymoses or purpura (meningococcemia)

Question 40

Serpiginous

Answer 40

shaped like a snake (larva migrans)

Question 41

Verrucous

Answer 41

wartlike

Question 42

xerosis

Answer 42

dry skin

Question 43

Screening for Melanoma: ABCDE

Answer 43

A → Asymmetry
B → Border irregular
C → color varies in the same region
D → diameter >6 mm
E → enlargement or change in size

Other sx to watch for: intermittent bleeding with mild trauma and new onset of itching

Question 44

1. Most common cancer in the US
2. Most common type of that cancer

Answer 44

1. Skin cancer
2. Basal cell skin carcinoma

Question 45

Macule

Answer 45

flat nonpalpable lesion <1cm in diameter

Ex: freckles (ephelis), lentigo or lentigines (plural)

Question 46

Papule

Answer 46

palpable solid lesion ≤ 0.5 cm in diameter

Ex: Nevi (moles), acne, small cherry angiomas

Question 47

Plaque

Answer 47

flattened, elevated lesion with variable shape >1 cm in diameter

Ex: Psoriatic lesions

Question 48

Bulla

Answer 48

Elevated superficial blister filled with serous fluid and >1 cm in size

Ex: Impetigo, 2º burns with blisters, SJS lesions

Question 49

Vesicle

Answer 49

elevated superficial skin lesion <1 cm in diameter, filled with serous fluid

Ex: Herpetic lesions

Question 50

Pustule

Answer 50

elevated superficial skin lesion <1 cm in diameter, filled with purulent fluid

Ex: acne pustules

Question 51

Secondary skin lesions
1. Definition

Answer 51

Primary lesions that changes; complication of a primary lesion or injury

Question 52

Lichenification

Answer 52

Secondary skin lesion

Thickening of the epidermis with exaggeration of normal skin lines d/t chronic itching (eczema)

Question 53

Scale

Answer 53

Secondary skin lesion

flaking skin (psoriasis)

Question 54

Crust

Answer 54

Secondary skin lesion

dried exudate, may be serous exudate (impetigo)

Question 55

Ulceration

Answer 55

Secondary skin lesion

Full-thickness loss of the skin (decubiti or pressure injury)

Question 56

Scar

Answer 56

Secondary skin lesion

Permanent fibrotic changes following damage to the dermis (surgical scar)

Question 57

Keloids/hypertrophic scar

Answer 57

Secondary skin lesion

Overgrowth of scar tissue; more common in Blacks, Asians

Question 58

Urticaria
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 58

1. Aka Hives
   - Skin that is compressed (e.g., with tight bra straps); may have lesions that assume a shape (ex. linear shaped lesions under bra strap)
   - chronic if > 6 wks
   - Multiple etiologies: medications, viral/bacterial infections, insect bites, latex allergies
2. Erythematous and raised skin lesions with discrete borders
   - irregular
   - oval or round
   - Lesions become more numerous and enlarge over mins to hours
   - then disappears; self-limiting
   - may occur as one episode or recurrent (usually daily), resolving in 24 hours, then recur
3. • If cause is eliminated, urticaria will resolve
     - If associated with angioedema or progresses to anaphylaxis → life-threatening! Refer to ED!

Question 59

Seborrheic Keratoses
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 59

1. • growths that appear during middle age (or later)
     - become more numerous as patient gets older
2. • soft, wartlike, fleshy growths in the trunk
     - located mostly on the back
     - lesions look like they are “pasted” on skin
     - can range in color from light tan to black
3. No treatment needed

Question 60

Xanthelasma
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 60

1. Aka plane xaxnthomas
   - ~50% of pts have hyperlipidemia
   - If <40 years → rule out hyperlipidemia
   - If located on fingers → pathognomonic for familial hypercholesterolemia
2. • raised and yellow-colored soft plaques, usually located under the brow or upper and/or lower lids of the eyes on the nasal
3. • Order fasting (8-12 hr) lipid panel

Question 61

Melasma
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 61

Aka Mask of Pregnancy
1. - more common in dark-skinned women

2. • Bilateral brown- to tan-colored stains located on the upper checks, malar area (cheeks and nose), forehead, and chin in some women who have been or are pregnant or on oral contraceptive pills (estrogen)
     - Stains are usually permanent but lightens over time

Question 62

Vitiligo
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 62

1. • loss of epidermal melanocytes
     RF: autoimmune disease (e.g., Graves’ disease, Hashimoto’s thyroiditis, RA, psoriasis, pernicious anemia)
     - more obvious and disfiguring in pts with darker skin
2. • white patches of skin (hypopigmentation) with irregular shapes
     - gradually develop, coalesce, and spread over time
     - chronic and progressive
     - can be located anywhere in the body
     - lesions may remain stable or are associated with flare-ups
3. Refer to dermatology for treatment options (e.g., topical steroids, light therapy)
   - advise patient to use sunscreen
   - avoid prolong sun exposure (makes white patches more obvious)
   - can have a major impact on patients’ self-image and self-esteem

Question 63

Cherry Angioma
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 63

1. Lesions d/t nest of malformed arterioles in skin
   - more common in middle-aged to older pts
2. • benign, small, and smooth round papules; bright cherry-red color
     - size from 1-4 mm
     - always blanch with pressure
3. No treatment necessary; benign

Question 64

Lipoma
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 64

1. • Most common type of benign soft tissue tumor
2. • soft, fatty cystic tumors
     - usually painless
     - located in subcutaneous layer of skin in the neck, trunk, and arms
     - usually round or oval shape
     - size 1-10 cm or more
     - smooth with discrete edges
     - asymptomatic unless they become too large or irritated or ruptures
3. Surgical excision is an option

Question 65

Nevi
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 65

1.

2. • Round macules to papules (junctional nevi)
     - colors ranges from light tan to dark brown
     - borders may be distinct or slightly irregular
     - often concentrated on trunk and lower extremities (girls)

Junctional nevi
- macular or minimally raised
- colors ranging from brown to black

compound nevi
- pigmented papules
- vary in color from tan to medium brown

3. No interventions necessary

Question 66

Xerosis
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 66

1. Inherited skin disorder → extremely dry skin
2. • extremely dry skin
     - may involve mucosal surfaces (e.g., mouth [xerostomia] or conjunctiva of the eye [xerophthalmia])

3

Question 67

Acanthosis Nigricans
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 67

1. • Associated with diabetes, m etabolic syndrome, obesity, and cancer of the GI tract
2. • diffuse velvety thickening of skin
     - usually located behind neck and axilla

Question 68

Acrochordon
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 68

aka Skin Tags
1. up to 50% of adults
- more common in diabetics and obese

2. • painless and pedunculated outgrowths of skin
     - some are same color as pt’s skin
     - common locations: neck and axilla
     - when twisted or traumatized (ex, caught up on neckless), skin tag can become necrotic and drop off the skin

Question 69

Topical Steroids
1. What type of infection etiology should you avoid?
2. Potency classes
3. When are steroids most effective?
4. What type of skin can absorb more of the steroids?

Answer 69

1. Avoid in suspected fungal etiology because it will worsen the infection
2. Can range from class 1 (super potent) to class 7 (least potent)
3. Steroids are most effective when applied within 3 minutes after bathing
4. Sensitive skin – face, genitals, intertriginous areas (under breasts, intergluteal folds, inner things)

Question 70

Topical Steroids
1. General considerations regarding topical steroids in children and areas with sensitive skin

Answer 70

1. Do not use fluorinated topical steroids
   - Use class 7 (least potent) topical steroids
   - Class 6 (mild potency) (ex. fluocinolone acetonide [Synalar cream/solution]) are prescription drugs.
   - Go to next class of potency if OTC hydrocortisone is not working

Question 71

Topical Steroids
What happens with prolonged topical steroid use?

Answer 71

The hypothalamic-pituitary-adrenal (HPA) axis suppression may occur with excessive or prolonged use (>2 weeks), esp in infants and children, with use of potent to ultrapotent topical steroids.

→ can cause striae, skin atrophy, telangiectasia, acne, and hypopigmentation

Question 72

Topical Steroids
Super-high potency, uses and example(s)

Answer 72

Use for severe dermatoses (psoriasis, severe eczema) on nonfacial and nonintertriginous areas for up to 2 weeks.

Works well on palms, scalp, and soles, which have “thicker” skin

Ex: Class 1 (super high) - Halobetasol propionate 0.5% (Ultravate) Daily-BID (2 weeks max)

Class 2 (high) - Halcinonide 0.1% (Halog) BID-TID

Question 73

Topical Steroids
Medium-high potency, uses and example(s)

Answer 73

use on mild-to-moderate nonfacial and nonintertriginous areas

Ex: Class 3 (medium-high) - Triamcinolone acetonide 0.1% (Kenalog) BID-TID

Class 4 (medium) - Mometasone furoate 0.1% (Elocon) BID-QID

Question 74

Topical Steroids
Low-medium potency, uses and example(s)

Answer 74

Use on larger areas that need treatment

Ex: Class 5 (low-medium) - Desonide 0.05% (Desonate) BID-QID

Class 6 (low) Fluocinolone acetonide 0.01% (Synalar) BID-QID

Question 75

Topical Steroids
Low-potency, uses and example(s)

Answer 75

Use on eyelid and genital areas for limited duration. Ophthalmic form of topical steroid is used on eyelids

Ex: Class 7 (least potent) - Hydrocortisone 1% BID-QID (OTC; no Rx needed)

Question 76

Psoriasis
1. Definition/Etiology
2. Clinical Presentation
3. Treatment
4. Complications

Answer 76

1. Inherited skin disorder where squamous epithelial cells undergo rapid mitotic division and abnormal maturation. The rapid tumor produces the classic psoriatic plaque; there are several phenotypes:
   - plaques (80%)
   - guttate
   - inverse
   - erythrodermic
   - pustular psoriasis
   - psoriatic arthritis (accounts for 5-30% of cases)
   - Chronic disease with exacerbation (e.g., infections, stress)
2. • pruritic erythematous plaques covered with fine silvery-white scales along pitted fingernails and toenails
     - plaques are distributed in the scalp, elbows, knees, sacrum, and intergluteal folds
     - partially resolving plaques are pink-colored with minimal scaling
     - psoriatic arthritis → painful red, warm, and swollen joints (migratory arthritis) + skin plaques

Special findings:
- Koebner phenomenon: new psoriatic plaques form over areas of skin trauma
- Auspitz sign: Pinpoint areas of bleeding in the skin where scales from a psoriatic plaque are removed

3. • Topical steroids, topical retinoids (tazarotene),k tar preparations (psoralen drug class)
     - Severe disease → Methotrexate, cyclosporine, biologics (etanercept, adalimumab)
4. Guttate psoriasis (drop-shaped lesions): severe form of psoriasis → beta-hemolytic streptococcus group A infection (usually d/t “strep” throat)

Question 77

Koebner phenomenon

Answer 77

new psoriatic plaques form over areas of skin trauma

Question 78

Auspitz sign

Answer 78

Pinpoint areas of bleeding in the skin when scales from a psoriatic plaque are removed

Question 79

Black Box Warnings
Topical Tacrolimus

Answer 79

Rare cases of malignancy (including skin and lymphoma)
- Use sunblock
- Avoid if patient is immunocompromised

Severe disease → Antimetabolites (e.g., methotrexate), biologics/antitumor necrosis factor (TNF) agents

Question 80

Black Blox Warnings
Biologics/ Antitumor Necrosis Factor Agents

Answer 80

Humira, Enbrel, and Remicade → associated with ↑ risk of serious/fatal infections, malignancy, TB, fungal infections, and sepsis (baseline purified protein derivative [PPD]j, CBC w/ diff)

• Goeckerman regimen (UVB light and tar-derived topicals) may induce remission in severe cases

Question 81

Actinic Keratoses
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 81

1. Precancerous precursor to SCC.
   Highest RF:
   - Older adults with fair skin, light-colored hair (blond, red) and blue eyes with skin type I or II (white skin)
   - +/- hx of chronic sun exposure (UV light)
   - hx of blistering sunburns or frequent sunburned places as a child ↑ risk, esp melanoma
2. • numerous dry, round, and pink-to-red lesions with a rough and scaly texture, do not heal
     - lesions are slow growing
     - become more numerous with age
     - most common locations are sun-exposed areas (cheeks, nose, face, neck, arms, and back)
3. Refer to dermatology for biopsy (GOLD STANDARD)
   - surgery - cryotherapy - topical medications (e.g., fluorouracil cream 5% [5=FU], imiquimod)
   - If small # of lesions → cryo
   - large # → 5-FU over several wks; selectively destroys sun-damaged cells in skin but can cause inflammation that appears as erythema (redness), oozing, crusting, scabs, and soreness; disappears in a few weeks

Question 82

Tinea Versicolor
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostics
4. Treatment

Answer 82

1. Superficial skin infection caused by yeast Pityrosporum orbiculare or P. ovale
2. • multiple hypopigmented round macules on chest, shoulders, and/or back
     - usually “appear” after skin becomes tan from sun exposure
     - skin infection is asymptomatic
3. Potassium hydroxide (KOH) slide: Hyphae and spores (“spaghetti and meatballs”)
4. • Topical selenium sulfide
     - optical azole antifungals (e.g., ketoconazole [Nizoral] and terbinafine [Lamisil] cream BID x 2 weeks)
     - advise pt that hypopigmented spots will not spontaneously disappear after treatment; may take several months for pigment to fill in

Question 83

Atopic Dermatitis (Eczema)
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostics
4. Treatment

Answer 83

1. Chronic inherited skin ds marked by extremely pruritic rashes
   - located on hands, flexural folds, and neck (older child to adult)
   - rash exacerbated by stress and environmental factors (e.g., winter)
   - associated with atopic ds such as asthma, allergic rhinitis, and multiple allergies (check for fam hx of atopy)
   - infants and up to 2 y.o. → larger area of rash distribution compared with teens and adults
2. • rash typically found on cheeks, entire trunk, knees, and elbows for infants/children
     - older children/adults → rashes on hands, neck, and antecubital and popliteal space (flexural folds)
     - classic rash → starts as multiple small vesicles that rupture, leaving painful, bright-red, weepy lesions.
     - lesions become lichenified from chronic itching → can persist for months
     - fissures form that can be secondarily infected with bacteria
3. Clinical diagnosis
4. • First line: Topical steroids & emollients
     mild ds → hydrocortisone 2.5% (low-potency, class V)
     moderate ds → triamcinolone acetonide (medium-potency, class IV)
     - Facial skin and skin folds/intertriginous area → higher risk for skin atrophy → tx w/ hydrocortisone 1% (low-potency, class VII)
     - Halcinonide (Halog): high-potency (class II) topical steroid
     - Oral antihistamines for pruritus: diphenhydramine (benadryl) and hydroxyzine (vistaril)
     - avoid drying skin/xerosis → will exacerbate eczema (e.g., no hot baths, harsh soaps, chemicals, wool clothing)
     - hydrating baths (avoid hot water/soaps) → followed immediately by skin lubricants )Eucerin, Keri Lotion, Crisnco, mineral oil); do not wait until skin is dry before applying

Question 84

Atopy

Answer 84

the genetic tendency to develop allergic diseases such as allergic rhinitis, asthma and atopic dermatitis (eczema). Atopy is typically associated with heightened immune responses to common allergens, especially inhaled allergens and food allergens

Question 85

Contact Dermatitis
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostics
4. Treatment

Answer 85

1. Inflammatory skin reaction caused by direct contact with an irritating external substance
   - can be single lesion or generalized rash (e.g., sea bather’s itch)
   TWO TYPES: irritant and allergic
   - Common offenders: poison ivy (Rhus dermatitis), nickel, latex rubber, chemicals, etc.
   - Onset can occur within mins to several hours after skin contact
2. • acute onset of one/multiple bright-red and pruritic lesions
     - evolve into bullous or vesicular lesions; easily rupture → bright-red moist areas, painful
     - c/o burning or stinging
     - when rash dries → crusted, very pruritic, and lichenified from chronic itching
     - shape may follow a pattern (e.g., ring around a finger) or asymmetric distribution
3. Hx and clinical diagnosis
4. • stop exposure to substance
     - topical steroids applied 1-2x/day x1-2 weeks
     - if skin is lichenified or does not involve fact or flexural areas → high-potency steroid (triamcinolone, halcinonide), calamine lotion or oatmeal baths (aveeno) PRN
     - Consider allergist referral for patch testing

Question 86

Contact Dermatitis
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostics
4. Treatment

Answer 86

1. Inflammatory skin reaction caused by direct contact with an irritating external substance
   - can be single lesion or generalized rash (e.g., sea bather’s itch)
   TWO TYPES: irritant and allergic
   - Common offenders: poison ivy (Rhus dermatitis), nickel, latex rubber, chemicals, etc.
   - Onset can occur within mins to several hours after skin contact
2. • acute onset of one/multiple bright-red and pruritic lesions
     - evolve into bullous or vesicular lesions; easily rupture → bright-red moist areas, painful
     - c/o burning or stinging
     - when rash dries → crusted, very pruritic, and lichenified from chronic itching
     - shape may follow a pattern (e.g., ring around a finger) or asymmetric distribution
3. Hx and clinical diagnosis
4. • stop exposure to substance
     - topical steroids applied 1-2x/day x1-2 weeks
     - if skin is lichenified or does not involve fact or flexural areas → high-potency steroid (triamcinolone, halcinonide), calamine lotion or oatmeal baths (aveeno) PRN
     - Consider allergist referral for patch testing

Question 87

Superficial Candidiasis
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostics
4. Treatment

Answer 87

1. Superficial skin infection from yeast Candida albicans
   - environmental factors promoting overgrowth: ↑ warmth and humidity, friction, obesity, diabetes, and ↓ immunity
   - can infect skin and mucous membranes (thrush, vaginitis) and systemically
   - intertrigo/intertriginous areas can be infected by fungal (candidal intertrigo) and/or bacterial organisms
2. External (Skin)
   - bright red and shiny lesions, itchy or burns
   - located in intertriginous areas (under breasts [women], axillae, abdomen, groin, web spaces between toes)
   - rash may have satellite lesions (small red rashes around main rash)

Thrush
- severe sore throat with white adherent plaques with red base; hard to dislodge on pharynx
*Thrust in healthy adults, not on antibiotics, may indicate immunodeficient condition

4. • Nystatin powder and/or cream in skin folds BID
     - OTC topical antifungals are miconazole and clotrimazole; prescription required for terconazole and ciclopirox
     - keep skin dry and aerated
     - clotrimazole troches (one troche dissolved in mouth slowly 5x/day( or miconazole mucoadhesive buccal tablets
     - Nystatin (Mycostatin) PO suspension for oral thrust (swish and swallow) QID
     - “Magic mouthwash” (viscous lidocaine, diphenhydramine, maalox); compound for severe sore throat (thrush, canker sores, mouth ulcers)
     - HIV-seropositive pt: oropharyngeal candidiasis is most common opportunistic infection
     - mod-severe cases (or recurrent): oral fluconazole is preferred systemic antifungal agent

Question 88

Cellulitis
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostics
4. Treatment

Answer 88

1. Acute skin infection of deep dermis and underlying tissue
   - usually caused by gram+
   TWO forms: purulent and nonpurulent
   - points of entry: skin breaks, insect bites, abrasions, or preexisting skin infections (tinea pedis, impetigo)
   - Community-acquired MRSA strain (USA300 MRSA) → virulent strain that causes aggressive skin infections
   - See other cards for different types
2. • acute onset of diffused pink- to red-colored skin; poorly demarcated with advancing margins
     - lesions warm to touch
     - may become abscessed; abscess (boils) usually d/t staphylococcus or MRSA
     - may be fluctuant (pointing) or draining pus
     - infection may spread to lymph node chains (lymphangitis) → appears red streaks radiating from infected area
     - may involve lymphadenothy
     - may have systemic symptoms
     - most common is lower limb

3 & 4. Treatment depends on culture

Question 89

Cellulitis: Orbital cellulitis and peritonsillar cellulitis tx

Answer 89

Refer to ED for parenteral abx

Question 90

Cellulitis: Purulent form of cellulitis; location

Answer 90

S. aureus (gram+)
Community-acquired MRSA, now common
Most cases are located on lower leg 85%

Question 91

Cellulitis: Nonpurulent form of cellulitis

Answer 91

Usually d/t streptococci (but may also staphylococcal)

Question 92

Cellulitis: Cat bites, common pathogen

Answer 92

Pasteurella multocida (gram-)

Question 93

Cellulitis: Dog bites, common pathogen

Answer 93

P. multocida, P. canis, Capnocytophaga

Question 94

Cellulitis: Puncture wounds (foot)
What is it? possible pathogen

Answer 94

Contaminated with soft foam liner material or puncture wounds through sneakers.
May be at risk for infection with Pseudomonas aeruginosa

Question 95

Cellulitis: Vibrio vulnificus
1. Definition
2. Leading cause of what-related cause of death in the US?
3. Special population considerations.

Answer 95

1. Exposure of wound to brackish water or saltwater (or eating raw oysters/clams) from the Gulf Coast or Chesapeake Bay can cause infection with this bacterium
2. Leading cause of shellfish-associated death in the US
3. People with liver disease, immunocompromised status, or pregnant women → AVOID eating raw or undercooked oysters or clams d/t possibility of Vibrio vulnificus infection → high mortality (50%) from V. vulnificus septicemia

Question 96

Clenched-fist Injuries
1. High risk for what?
2. Treatment?

Answer 96

1. HIgh risk for infection of joints (e.g., knuckles), fascia, nerves, and bones (osteomyelities; esp if punched in the mouth or bitten by a human
2. Refer to ED! There may be foreign body embedded (e.g., tooth → Xray needed) and/or fracture

Question 97

Necrotizing Fasciitis (“Flesh-eating” Bacteria)

Answer 97

Reddish to purple-colored lesions that increases rapidly in size.
- may have bullae
- infected areas appears indurated (“woody” induration) with complaints of severe pain on affected size

Question 98

Folliculitis

Answer 98

Infection of the hair follicle(s)
- May involve several follicles
- Small (1 mm) round lesions filled with pus with erythema
- usually self-limiting
- Avoid shaving or scrubbing area
- Consider mupirocin (Bactroban) ointment or cream

Question 99

Furuncles (Boils)
1. Definition
2. Treatment

Answer 99

1. an infected hair follicle filled with pus (abscess)
   - may start out as folliculitis that worsened
   - round red bump; hot and tender to the touch
   - When it is fluctuant → can rupture and drain purulent green-colored discharge
2. • Apply antibiotic ointment BID and cover with dressing until healed
     - For small boils → use warm compress BID
     - If abscess >2cm, I&D and/or empiric antibiotic treatment
     - If located over a joint → Refer to ED for xray of joint to r/o osteomyelitis
     - MRI is best imagining to detect bone infection

Question 100

Carbuncles
1. Definition
2. Clinical Presentation
3. Labs/Diagnostic
4. Treatment
5. Follow-up
6. Complications

Answer 100

1 & 2. Several boils that coalesce to form a large boil or abscess
- may have several “heads”

3. • Culture and sensitivity (C&S) advancing edge of lesion (if fluid or pus, vesicles, drainage)
     - LE cellulitis, also fungal culture for tinea pedis (swab interdigital spaces)
     - CBC if fever or toxic or suspect necrotizing fasciitis → Refer to ED!
4. If toxic, rapid progression, immunocompromised, diabetic, or joint involvement → suspect osteomyelitis & refer to ED for parenteral antibiotics
   - Nonpurulent cellulitis (non-MRSA) → Dicloxacillin PO QID x 10 days (preferred d/t high rate of beta-lactam resistance); cephalexin QID or clindamycin TID x 10 days
   - Penicillin allergic: azithromycin (Z pack) x 5 days
   - Suspect MRSA: Bactrim DS 1 tab BID or doxycycline or minocycline PO BID x 10 days or clindamycin TID-QID x 10 days (mild case → 5 days)
   - Td booster: if last dose was >5 years ago
   - Elevate affected limb
5. Follow up within 48 hours; pt treated with PO antibiotics should start to show improvement in 48-72 hours. Refer cellulitis if:
   - systemic symptoms develop (3e.g., fever, toxic) or worsens
   - Cellulitis is not responding to treatment within 48 hours
   - Cellulitis is spreading quickly or is a small lesion with a black center (gangrene) associated with severe pain (necrotizing fasciitis)
   - Patient is diabetic, immunocompromised, or taking anti-TNF agents (RA)
6. • Osteomyelitis, septic arthritis, sepsis
     - Tendon and fascial extension
     - Rarely, death (high fatality rates for V. vulnificus infections)

Question 101

Erysipelas
1. Definition
2. Clinical Presentation
3. Treatment

Answer 101

1. A subtype of cellulitis involving upper dermis and superficial lymphatics, usually caused by Group A streptococcus
   - For facial erysipelas → assume MRSA and choose antibiotic that covers MRSA
2. • Sudden onset of one large hot and indurated red skin lesion
     - has clear demarcated margins
     - usually located on LE (the shins) or the cheeks
     - accompanied by fever and chills
3. Hospitalization since pt may be bacteremic

Question 102

Bites: Human and Animal
1. Human Bites definition
2. Dog and Cat Bites definition
3. Treatment

Answer 102

1. The “dirtiest” bite of all; watch for closed-fish injuries of the hands (may involve join capsule and tendon damage)
   - Eikenella corrodens and numerous bacteria may be involved
2. P. multocida (gram-) most common pathogen
   - dog bites also carry capnocytophaga canimorsus (gram-)
   - cat bites have ↑ risk of infection than dog

Signs of infection:
- redness
- swelling
- pain
- systemic symptoms may develop 12-24 hours

3. • Amoxicillin-clavulanate (Augmentin) 875 mg/125 mg PO BID x 10 days
     - Penicillin allergy: Doxycycline BID, Bactrim DS BID + coverage for anaerobes combined w/ metronidazole (Flagyl) BID or clindamycin TID
     - Irrigate copiously with sterile saline; all bites and infected wounds need wound C&S
     - Do NOT suture wounds at high risk for infection: puncture wounds, wounds >12 hours old (24 hours on face), infected bite wounds, cat bites
     - Cartilage injuries (cartilage does not regenerate) → Refer to plastic
     - Tetanus prophylaxis (if last booster >5 years, need boosters)
     - Follow-up w/ patient within 24-48 hours after treatment

Question 103

Bites: Human and Animal
Referral of Wounds

Answer 103

• Closed-fist injuries or crush injuries → Refer to hand surgeon
• Cartilage damage or wounds with cosmetic effects → Refer to plastic
• Compromised hosts → Consider adult diabetics, absent/dysfunction of the spleen, and immunocompromised

Question 104

Bites: Rabies
1. Definition/Etiology
2. Vaccination
3. Treatment

Answer 104

1. Consider bats, raccoons, skunks, foxes, and coyotes (domestic animals can also have rabies)
   - If dog, check if dog received rabies vaccine recent (within 1 year)
   - Rabies rarely seen in rodents such as mice, rats, squirrels, hamsters, guinea pigs, or rabbits

2 & 3. Rabies immune globulin + rabies vaccine may be required
- Call local health department for advice
- consider if wild animal acts tame, produces copious saliva, attacks without provocation, or looks ill
- Option: Quarantine a domestic animal for 10 days
- look for signs and symptoms of rabies

Question 105

Hidradenitis Suppurativa
1. Definition/Etiology/Stages
2. Clinical Presentation
3. Lab/Diagnostic
4. Treatment

Answer 105

1. Chronic and recurrent inflammatory disorder of the apocrine glands, resulting in painful nodules, abscesses, and pustules
   - locations: axilla (most common), mammary area, perianal area, and groin
   - More common in women 3:1
   - RF: smoking and obesity
   - No cure

Stages:
I - nodule, abscess formation without sinus tracts or scarring
II -
III - multiple interconnected tracts, abscesses, scarring

2. • Recurrent episodes of painful, large, dark-red nodules, abscesses, and pustules
     - Ruptured lesions drain purulent green-colored discharge
     - pain resolves when abscess drains and heals
     - lesions take from 10-30 days to heal
     - hx of recurrent episodes on the same area in the axilla results in sinus tracts, keloids, and multiple scars
     - may be anxious and/or depressed

3&4. Stage I
- Either systemic or topical antibiotics: clindamycin, clindamycin with benzoyl peroxide, chlorhexidine (Hibiclens) 4% solution
- PO antibiotics: tetracycline 500 mg BID; doxycycline or minocycline BID x 7-10 days

Stage II - III
- Topical antibiotics: clindamycin 1% solution w/ or w/out benzoyl peroxide, chlorhexidine (Hebiclens) 4% solution
- PO antibiotics: clindamycin, moxifloxacin, and metronidazole for 6 months

• Warm compresses, sitz bathjs, topical and/or oral pain meds for pain
• Diet: Avoid high glycemic foods, dairy
• Smoking cessation, weight loss if obese
• Refer to dermatologist. Options: surgery, hormonal therapy, interlesional steroids, PO retinoids, metformin, biologics, laser therapy, and cryotherapy

Question 106

Impetigo
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostic
4. Treatment

Answer 106

1. acute superficial skin infection caused by gram+ ( beta streptococcus or streptococcus aureus)
   - most common bacterial skin infection in young children ages 2-5
   - more common in hot and humid environments (summer, subtropics, tropics)
   - can appear on normal skin or skin breaks (scratches, insect bites, acne, varicella lesions)
   - if infection d/t beta streptococcus (S. pyogenes), postglomerular nephritis can be a complication
   - TWO types: bullous (30%) and nonbullous (70%)
2. • acute onset of itchy pink-to-red lesions → evolves into vesiculopustules that rupture
     - bullous impetigo appears as large blisters, ruptures easily
     - after rupture, red, weeping, shallow ulcers appear
     - when serous fluid dries up → looks like lesions covered with honey-colored crusts
     - can present with few (2-3) to multiple lesions
3. C&S of crusts/wound
4. • Severe cases: Cephalexin (Keflex) QID, dicloxacillin QID x 10 days
     - Penicillin allergic: azithromycin 250 mg x 5 days (macrolides), clindamycin x 10 days
     - If few lesions with no bullae, topical 2% mupirocin ointment (Bactroban) or fusidic acid 2% cream x 10 days may be useful
     - clean lesions w/ antibacterial soap, betadine, or chlorhexidine (Hibiclens), then apply topical antibacterial to lesions
     - shower/bath daily w/ antibacterial soap until healed; do not share towels
     - Children in daycare: do not return to school until 48-72 hours after initiation of treatment

Question 107

Meningococcemia
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostic
4. Prophylaxis
5. Treatment
6. Complications

Answer 107

1. serious life-threatening infection caused by N. meningitidis (gram- diplococci), spread by respiratory droplets
   - bacterial meningitis is a medical emergency!!!
   - mortality rate: 10-14%
   - use droplet precautions
   - do NOT delay treatment if high index of suspicion → Refer to ED stat!
2. “Danger signals”
3. • LP: culture cerebrospinal fluid (CSF)
     - Blood cultures, throat cultures, and the like (do NOT delay treatment to wait for lab results)
     - CT or MRI of the brain
4. • Close contacts (give as early as possible): Rifampin PO Q12H x 2 days
     - Close contacts: being in close proximity to patient (<3 feet) who has had prolonged contact (>8 hours) or directly exposed to pt’s PO secretions, going back to 7 days before onset of pt’s symptoms until 24 hours after initiation of antibiotics
     - Meningococcal vaccinations: The CDC recommends vaccination w/ meningococcal conjugate vaccine (MCV4 9or Menactra) for freshman college students living in dormitories, military recruits, persons w/ asplenia, or a nonfunctioning spleen (e.g., sickle cell), patients on eculizumab (Soliris), or others
     - Routine meningococcal polysaccharide (MPSV4 or Menomune) vaccine: recommended for all preteens and teens (age 11 dose w/ booster age 16)
5. • Ceftraixone (Rocephine) 2g IV Q12H + Vancomycin IV Q8-12H
     - Hospital, isolation precautions, supportive treatment
6. • Tissue infarction and necrosis (e.g., gangrene of the toes, foot, fingers) causing amputation
     - Death

Question 108

Early Lyme Disease
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostic
4. Treatment
5. Complications

Answer 108

1. • Erythema migrans, a skin lesion caused by the bite of an Ixodes tick infected with Borrelia burgdorferi
     - If untreated → infection becomes systemic → affects multiple organ systems
     - may have only rash or rash may be accompanied by flu-like symptoms
2. “Danger Signals”
3. Two-step (two tier) testing recommended (designed to be done together)
   - First step: enzyme immunoassay (EIS); if negative, no further testing is recommended
   - If first test is positive (or equivocal/indeterminate), the second step test is the indirect immunofluorescence assay (IFA, or immunoblot test or “western blot” test)
4. • Early Lyme Disease only: Doxycycline BID x 10 days (first line drug for both adults and children)
     - Alternative: Amoxicillin 500 mg TID or cefuroxime axetil (Ceftin) 500 mg BID x 14 days
5. Neuropathy (e.g., facial palsy, impaired memory
   - Lyme arthritis, chronic fatigue

Question 109

Rocky Mountain Spotted Fever
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostic
4. Treatment
5. Complications

Answer 109

1. Caused by the bite of a dog tick (wood tick), infected with parasite Rickettsia rickettsii
   - if high suspicion, do not delay treatment (do not wait for lab results)
   - Treatment most effective if treated within first 5 days of symptoms
   - First-line treatment: doxycycline for all age groups → drug of choice for RMSF and all other tickborne rickettsial disease for both children and adults
   - Check if resident of the southeastern or south-central states (NC, TN, OK, AK, MO) or visitor
   - Early diagnosis and treatment with doxycycline are critical to survival
   - RMSF = reportable disease
2. • “Danger signal”
     - can be difficult to diagnose d/t nonspecific s/s in early stages of infection; initially, diagnosis is based on s/s
     - ALWAYS take a thorough history and include important areas such as travel hx (esp from areas where RMSF is endemic) and exposure factors (brushy or woody areas with high grasses and leafy litter)
     - In Arizona & Mexico → ask about exposure to dogs
     - Rick bites are often painless; do NOT r/o RMSF even if pt does not remember a tick bite esp if hx of being in woody or bushy area with leaf and high grasses
3. • Diagnostics: Antibody titers to R. rickettsii (by indirect fluorescent IgG antibodies or IFA assay)
     - IgG IFA assays on paired acute and convalescent serum samples (collected 2-4 weeks apart) → e/o four-fold seroconversion
     - RMSF cannot be confirmed using a single acute antibody result; antibodies to R. ricketsii might remain elevated for many months after disease has resolved
4. NEVER delay or withhold treatment based on lab results, even if initially negative result. Antibody titers are frequently negative in the early phase of the infection.
   - Presumptive treatment with doxycycline is recommended in all pts of all ages, including children <8 years; children ≤45 kg are dosed by weight
   - Treated should be based on s/s + hx; lab testing can be done later
   - First line treatment (adults and children): Doxycycline 100 mg PO or by IV BID x 7 days or for 2 days after normothermic
   - AAP states doxycycline can be given for short durations <21 days regardless of age
5. • Death
     - Neurologic sequelae (e.g., hearing loss, paraparesis, neuropathy)

Question 110

How to Remove a Tick

Answer 110

1. Use fine-tipped tweezers to grasp the part of the tick closest to the skin
2. Pull it upward with steady, even pressure. Do not twist or jerk.
3. After removing the tick, clean bite area with rubbing alcohol, iodine scrub, or soap and water. Dispose of the tick by flushing it into toilet. Do not crush the tick with bare fingers.

NOT effective: Painting the tick with nail polish or petroleum jelly or using heat to make the tick detach. The goal is to detach the tick as quickly as possible after it is found.

Question 111

Varicella-Zoster Virus Infections
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostic
4. Treatment
5. Complications

Answer 111

1. Chickenpox (varicella) and herpes zoster (shingles) are both caused by the varicella-zoster virus (VZV)
   - primary infection is called chickenpox (varicella) and the reactivation of the infection is known as shingles (herpes zoster)
   - after chickenpox, virus becomes latent within dermatome (sensory ganglia) and is kept under control by an intact immune system
   * Chickenpox: Contagious 1-2 days before the onset of the rash until all of the lesions have crusted over (chickenpox and shingles); duration of illness is 2 weeks
   * Shingles: Contagious w/ the onset of rashes until all lesions have crusted over
   - A susceptible person (who has never had chickenpox or been vaccinated) can become infected from shingles, but that person’s initial infection will manifest as chickenpox
   - only a person who has had chickenpox (rarely the chickenpox vaccine) can get shingles
2. Chickenpox/Varicella
   - Prodrome of fever, pharyngitis, and malaise followed within 24 hrs by eruption of pruritic vesicular lesions in different stages of development over a period of 4 days
   - rashes start on the head and face and quickly spread to the trunk and extremities
   - takes 1-2 wks for crusts to fall off and skin to heal

Shingles
- Elderly or older adults
- acute onset of groups of papules and vesicles on red base that rupture and become crusted
- crusted lesions follow dermatomal pattern on one side of the body
- c/o pain, which can be quite severe
- some w/ prodrome may have severe pain/burning sensation at site before the breakout
- can last 2-4 wks
- immunocomproised and elderly pts are at higher risk for postherpetic neuralgia (PHN)
- early treatment ↓ risk
- tx within 48-72 hours after onset of breakout if pt is >50 or immunocompromised
- completely cover lesions until dry and crusted

3. • s/s of herpes zoster are distinctive → clinical diagnosis
     - if atypical case or if suspected disseminated herpes zoster (lesions that are seen outside the primary dermatomes) → GOLD STANDARD: polymerase chain reaction (PCR)
4. • Acyclovir (Zovirax) five times per day or valacyclovir (Valtrex) BID x 10 days for initial breakout and 7 days for flare-ups
     - Most effective when started 48-72 hours after appearance of rash
5. • PHN: more common in elderly & immunocompromised pts → tx w/ tricyclic antidepressants (TCAs; e.g., low-dose amitriptyline), anticonvulsants (e.g., Depakote), or gabapentin TID + lidocaine 5% patch (lidoderm) to intact skin
     - Herpes zoster ophthalmicus (CN V): can result in corneal blindness → refer immediately to ophthalmologist or ED
     - Others: If Ramsay Hunt syndrome (herpes zoster oticus) triad of ipsilateral facial paralysis, ear pain, and vesicles in the ear canal and auricle → refer to neurologist

Question 112

Varicella-Zoster Virus Infection
Vaccines

Answer 112

• Varicella vaccine (adolescents and adults): A person can still become infected with VZV but will have mild disease with fewer lesions (compared with the unvaccinated); may have lesions that do not crust; *advise reproductive-aged women not to get pregnant within the next month after vaccine administration
• Singles/zoster vaccine (2006): One dose is recommended for persons ≥60 yo; hx of shingles or no hx of chickenpox infection is not a contraindication to vaccine
• Contraindications: People with AIDS or those on chronic high-dose steroids, undergoing radiation 9or chemotherapy, and the immunocompromised should not get the vaccine

Question 113

Herpetic Whitlow
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 113

1. Viral skin infection of the finger(s) caused by herpes simplex (type 1 & 2) virus infection
   - results from direct contact with either a cold sore or genital herpes lesion
2. • acute onset of extremely painful red bumps and small blisters on the sides of the finger, the cuticle area, or on the terminal phalanx of one or more fingers
     - may have recurrent outbreaks
     - ask pt about coexisting symptoms of oral herpes or genital herpes
3. Usually symptoms are treated
   - Self-limited infection: analgesics or NSAIDs for pain as needed
   - Severe infections: treat with acyclovir (Zovirax)

Patient Education:
- Avoid sharing personal items, gloves, and towels
- Cover skin lesions completely with large adhesive bandage until they heal

Question 114

Paronychia
1. Definition/Etiology
2. Clinical Presentation
3. Complications

Answer 114

1. Acute local bacterial skin infection of the proximal or lateral nail folds (cuticle), resolves after the abscess drains
   - Causative bacteria are S. aureus, streptococci, or Pseudomonas (gram-)
   - chronic cases are associated w/ coexisting onychomycosis (fungal infection of nails)
2. • acute onset of a painful and red, swollen area around nail on finger that eventually becomes abscessed
     - most common locations: index finger & thumb
     - reports a hx of picking a hangnail, biting off hangnail, or trimming of the cuticle during a manicure
3. • Soak affected finger or toe in warm water for 20 minutes TID
     - apply topical antibiotic, such as triple antibiotic or mupirocin, to the affected finger after soaking
     - Abscess: I&D (use no. 11 scalpel) or use the beveled edge of a large-gauge needle to gently separate the cuticle margin from the nail bed to drain the abscess

Question 115

Pityriasis Rosacea
1. Definition/Etiology
2. Clinical Presentation
3. Treatment

Answer 115

1. • Self-limiting illness (6-8 weeks)
     - this skin condition may be caused by a viral infection
2. • oval lesions with final scales following skin lines (cleavage lines) of the trunk or a “Christmas tree” pattern
     - salmon-pink color in white people
     - may be pruritic
     - “Herald patch” → first lesion to appear and is largest in size; appears 2 wks before full breakout; it is a single round-to-oval shape and about 2-5 cm in diameter
3. • Advise pt that lesions will take about 4 weeks to resolve
     - If high risk of STD, check rapid plasma reagent (RPR) to r/o 2º syphilis

Question 116

Scabies
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostic
4. Treatment
5. Complications

Answer 116

1. Infestation of the skin by the Sarcoptes scabiei mite
   - female mite burrows under the skin to lay her eggs; transmitted by close contact
   - may be asymptomatic the first 4-8 wks after infestation
   - even after treatment, the pruritis may persist for 2-4wks (sensitivity reaction to mites and their feces)
   - Higher incidence in crowded conditions (e.g., nursing homes) and homeless
2. • pruritic rashes located in the interdigital webs of the hands, axillae, breasts, buttock, folds, waist, scrotum, and penis
     - severe itching that is worse at nighttime and interferes with sleep
     - other family members may also have the same symptoms

Objective:
- rash appears as serpiginous (snakelike) or linear burrows
- lesions can be papular, vesicular, or crusted

3. Scrape burrow or scales with glass slide; use coverslip (wet mount). Look for mites or eggs.
4. • Permethrin 5% (Elimite): Apply cream from the neck to the sole of the feet after bathing or showering. Wash off after 8-14 hours. Repeat treatment in 7 days
     - The head/scalp, face, neck, palms, and soles are often involved in infants and very young children
     - Permethrin can be applied to scalp and face (sparing eyes and mouth) in infants and young children
     - Avoid using lindane lotion 1% (Kwell); BBW of severe neurologic toxicity
     - treat everyone in the same household at the same time; any clothes/bedding use 3 days before and during treatment should be washed and dried using the hot settings. another option is to place items in a plastic bag that is sealed for at least 72 hours
     - Pruritis usually improves in 48 hrs but can last up to 2-4 wks (even if mites are dead). Do NOT re-treat (do wet mount to check for live mites)
     - Treat itch with benadryl and topical steroids
     - Long-term care facility: Treat all patients, staff, family members, and frequent visitors for scabies!

Question 117

Norwegian Scabies

Answer 117

A severe form of scabies that affects the elderly and immunocompromised. Lesions are covered with fine scales (looks like white plaques) and crusts; involves the nails (dystrophic nails), scalp, body; absent-to-mild pruritis; very contagious. Itching may be absent. Treat with oral ivermectin combined with a topical agent (permethrin).

Question 118

Tinea Infections (Dermatophytoses)
1. Definition/Etiology
2. Lab/Diagnostic
3. Treatment

Answer 118

1. Infection of superficial keratinized tissue (skin, hair, nails) by tinea organisms
   - Tinea trichophyton, microsporum, and epidermophyton = dermatophytes
   - Tinea infection is classified by location
   - Most of tinea can be treated with topical antifungal medication except for tinea capitis and mod-severe onychomycosis or tinea unguium (toenails)
2. • Fungal culture of scales/hair/nails or skin lesions
     - KOH slide microscopy (low-medium power) reveals pseudohyphae and spores
3. • OTC topicals (cream, gels, sprays, solutions, powders)
     - OTC azoles/imidazoles: Clotrimazole (Lotrimin Ultra), naftifine (Naftin), once a day or BID, miconazole (Monistat) BID, ketoconazole (Nizoral) shampoo/cream once a day
     - Prescription topical azole: Terconazole (Terazol) BID
     - OTC allylamines: Terbinafine (Lamisil AT), butenafine (Lotrimin Ultra) once or BID
     - Tolnaftate (Tinactin): Apple BID
     - Avoid steroids unless severe inflammation (can ↓ effectiveness of antifungals)

Question 119

Tinea Capitis (Ringworm of the Scalp)
1. Definition/Etiology
2. Clinical Presentation
3. Treatment
4. Complications

Answer 119

1. Black dot tinea capitis (BDTC) → most common type in US.
   - African American children are at higher risk
   - Spread by close contact and fomites (shared hats, combs)
   - systemic treatment only (topicals are not effective)
2. • School-aged child with an asymptomatic scaly patch that gradually enlarges
     - hairs inside the patch break off easily by the roots (looks like black dots) → patchy alopecia
     - Black dot sign: Broken hair shafts leave a dot-like pattern on scalp
3. • Determine baseline LFTs and repeat 2 2wks after initiating systemic antifungal treatment → Monitor
     - GOLD STANDARD: Administer griseofulvin (microsize/ultramicrosize) daily to BID x 6-12 wks
     - Avoid hepatotoxic substances (alcohol, statins, acetaminophen)
     - Avoid sharing combs, headgear, towels, pillows, and clothes with others
4. Kerion: Inflammatory and indurated lesions that permanently damage hair follicles, causing patchy alopecia (permanent)

Question 120

Tinea Pedis (Athlete’s Foot)

Answer 120

Two types:
Scaly and dry form
- has scales, can include entire sole, edges of foot, or toes only

Moist type (strong odor)
- occur b/w toe webs
- have a strong unpleasant odor

Recurrences are common
- can spread to fingernails of the dominant hand from scratching feet (two feed-one hand syndrome)
- Ensure feet are dry after showering or bathing (can use blow-dryer to dry feet)

Question 121

Tinea Corporis or Tinea Circinata (Ringworm of the Body)

Answer 121

Ringworm causes ringlike pruritic rashes with a collarette of fine scales that slowly enlarge w/ some central clearing.

Most causes respond to topical azole antifungals (topical terbinafine 1%, butenafine 1%) for 2-3 wks

Question 122

Tinea Cruris (“Jock Itch”

Answer 122

• Perineal and groin area have pruritic red rashes with fine scales
• may be mistaken for candidal infection (bright-red rashes with satellite lesions) or intertrigo (bright-red diffused rash d/t bacterial infection)

Question 123

Tinea Manuum (Hands)

Answer 123

• Pruritic round rashes with fine scales found on hands
• Usually infected from chronic scratching of foot that is also infected with tinea (athlete’s foot)

Question 124

Tinea Barbae (Beard Area)

Answer 124

• Beard area is affected
• Scaling occurs with pruritic red rashes

Question 125

Onychomycosis (Nails)
1. Definition/Etiology
2. Clinical Presentation
3. Lab/Diagnostic
4. Treatment

Answer 125

1 & 2. - Nails become opaque, yellowed, and thickened with scaling under the nail (hyperkeratosis)
- also known as tinea unguium
- usually caused by dermatophytes but can be infected with yeast and molds
- most common type: distal subungual onychomycosis
- nail may separate from nail bed (onycholysis)
- great toe is most common location
- treated w/ systemic antifungals except for mild cases
- if mild → trial of topical treatment (penlac “nail polish”)

3. Funal cultures of affected nails for confirmation of infection; KOH for microscopy
4. • Both pulse therapy & continuous therapy are acceptable. Baseline LFTs. Monitor periodically
     - Administer oral terbinafine (Lamisil) x 12 wks or itraconazole for 1 wk per month for 2-4 cycles (pulse dosing). No need to monitor LFTs with pulse dosing
     - Mild-mod cases: Topical antifungals (efinaconazole [Jublia] and ciclopirox [Penlax]); apply nail lacquer x several weeks. Works best in mild cases on fingernails
     - Not all pts with onychomycosis require treatment. First line tx: oral antifungals but they may cause drug interactions and systmic effects

Question 126

Acne Vulgaris (Common Acne)

Answer 126

Inflammation and infection of the pilosebaceous units
- has multifactorial causes, such as high androgen levels, bacterial infection with cutibacterium (formerly known as Propionibacterium acnes), follicular hyperproliferation, and genetic influences)
- located mainly on face, shoulders, chest, and back
- highest incidence during puberty and adolescence

Question 127

Acne Vulgaris: Mild Acne
Open comedones vs closed comedones
Treatment

Answer 127

Open comedones (blackheads) and closed comedones (noninflammatory acne) with or without small papules → mild acne
- First-line: topical retinoids

Prescription medications; Tretinoin topical (retin-A), benzoyl peroxide gel with erythromycin (Benzamycin) or clindamycin topical (Cleocin)

Start at lowest dose: Tretinoin topical (Retin-A) 0.25% cream every other day at bedtime x2-3 wks then daily application at bedtime; alternative is azelaic acid or salicylic acid (OTC)

Retinoids also help ↓ facial wrinkles and hyper- or hypopigmentation.
- Advise pt that acne may worsen (first few weeks of use) with topical retinoids
- In about 4-6 wks, acene improves and clears up
- Facial skin can become red and irritated (dryness, itch, peeling) in the first few weeks of use
- Photosensitivity reaction is possible (use sunscreen)
- If no improvement within 8-12 wks, considering ↑ Retin-A dose or adding benzoyl peroxide with erythromycin

Question 128

Acne Vulgaris: Moderate Acne
Definition
Topicals + Antibiotics

Answer 128

Presence of papules and pustules (inflammatory lesions) w/ comedones is considered moderate acne

• First-line: Topical retinoids for comedonal acne – Topical retinoids (e.g., retinol, tretinoin, adapalene, tazarotene) → effective in both noninflammatory (comedones) and inflammatory (papules, pustules) acene; they come in cream, gel, or solution
• Apply topical retinoids about 20-30 mins after cleansing the face (avoid scrubbing face)
• Topical retinoids can be used alone in mild acne; with inflammatory acne, a topical retinoid can be used with a topical antimicrobial (benzoyl peroxide, erythromycin, clindamycin)
• If no improvement → oral antibiotics (tetracycline, minocycline, doxycycline,e rythromycin) at limited duration of 3-4 wks; use w/ topical benzoyl peroxide to ↑ effectiveness
• Tetracyclines can be given for acne from age 13, as growth of permanent teeth is finished except wisdom teeth (or third molars), which erupt b/w ages 17-25; tooth discoloration is not a consideration
• Tetracyclines (Category D): cause permanent discoloration of growing tooth enamel; NOT given during pregnancy or children <13 yo
• Certain oral contraceptives (Desogen, Yaz) are indicated for acne
• Role of diet: Limited evidence that some types of dairy (e.g., skim milk) may affect acne

Question 129

Acne Vulgaris: Severe Cystic Acne
Definition
Treatment

Answer 129

Consists of all of the preceding findings + painful indurated nodules, cysts, abscesses, and pustules over face, shoulders, and chest

• Isotretinoin (Accutane) is a category X (extremely teratogenic); can be prescribed only by prescribed who are registered in the iPLEDGE program
• Pt must use 2 forms of reliable contraception; prescribe 1-month supply only
• Monthly pregnancy testing w/ results shown to pharmacist is necessary before refills
• Pregnancy test is needed 1 month after treatment is discontinued
• Discontinue if the following are present: severe depression, visual disturbance, hearing loss, tinnitus, GI pain, rectal bleeding, uncontrolled hypertriglyceridemia, pancreatitis, hepatitis

Question 130

Rosacea (Acne Rosacea)
1. Definition
2. Clinical Presentation
3. Treatment
4. Complications

Answer 130

1. Chronic and relapsing inflammatory skin disorder that is more common in people with light-colored skin
   - First-line tx: aimed at symptom control and avoidance of triggers that cause exacerbations (e.g., spicy foods, alcohol, sunlight)
   - pt w/ rosacea have sensitive skin; advise to avoid irritating skin products (toners, alpha hydroxyl acids, strong soaps) and apply skin moisturizer frequently
   FOUR subtypes of rosacea:
2. • Light-skinned adult- older pt w/ Celtic background (e.g., Irish, Scottish, English) → chronic and small acne-like papule sand pustules around nose, mouth, and chin
     - Telangiectasis may be present on nasal area and cheeks
     - pt blushes eaily
     - usually blond or red-haired and has light-colored eyes
     - some have ocular symptoms such as red eyes, dry eyes, or chronic blepharitis (ocular rosacea)
3. • Lifestyle changes to ↓ flushing episodes (e.g., avoiding spicy foods, sunlight, alcohol, stressors)
     - sensitive skin, avoid scrubbing, strong soaps, cosmetic products that irritate the skin
     - frequent ski moisturization (avoid dry skin)
     - use mild sunblock

Meds:
- Metronidazole (Metrogel) topical gel
- Azelaic acid (Azalex) topical gel
- Lose-dose oral tetracycline or minocycline given over several wks
- alternative abx: clarithromycin w/ doxycycline for inflammatory lesions

4. • Rhinophyma: Hyperplasia of tissue at the tip of nose from chronic severe ds
     - Ocular rosacea: Blepharitis, conjunctival injection, lid margin telangiectasia

Question 131

Molluscum Contagiosum

Answer 131

Dome-shaped papules (2-4 mm diameter) w/ central umbilication (white plug)
- caused by skin infection with the poxvirus
- spread by skin-to-skin direct contact
- more common in children
- in immunocompetent host, usually clears up in 6-12 months
- CDC considers it an STD if lesions are located on the genitals in sexually active adolescents and adults

Question 132

Burns (Thermal Burns)
Minor Burn Criteria (American Burn Association)
Percentage of burn for the following:
- Partial-thickness
- Full-thickness
- Above criteria PLUS

Answer 132

Partial thickness:
- <10% of TBSA in pt 10-50 yo
- <5% of TBSA in pt <10 or > 50 yo

Full-thickness:
- <2% of TBSA in any pt without other injury

Above criteria PLUS
- May not involve face, hands, perineum, or feet
- May not cross major joints
- May not be circumferential
- No suspicion of inhalation injury
- No suspicion of high-voltage injury

Question 133

Superficial-Thickness Burns (First-degree)
Definition
Treatment

Answer 133

• Erythema only (no blisters
• painful (e.g., sunburns, mild scalds)
• Cleanse w/ mild soap and water (or saline)
• Cold packs for 24-48 hrs
• Intact skin doe snot require topical antibiotics
• apply a topical OTC anesthetic such as benzocaine if desired or aloe vera gel

Question 134

Partial-thickness Burns (Second-degree)
Definition
Treatment

Answer 134

• Red-colored skin w/ superficial blisters )(bullae)
• burn is painful
• Use water with mild soap or normal saline to clean broken skin (not hydrogen peroxide or full-strength Betadine)
• Do not rupture blisters
• Treat w/ silver sulfadiazine cream (Silvadene) or triple antibiotic ointment such as Polysporin (bacitracin zinc and polymyxin B) + nonadherent dressings
• Sulfadiazine can damage the eyes (do not use near eyes)
• Pregnant or breastfeeding women should not use sulfadiazine
• Apply biologic dressings (e.g., DuoDERM), Tegaderm, others
• Alternative medicine: use a topical application of honey or aloe vera

Question 135

Full-Thickness Burns (Third-degree_
Definition
Treatment

Answer 135

Initial assessment: r/o airway and breathing compromise
- Smoke inhalation injury is a medical emergency!
- Third-degree burns are painless
- Entire skin layer, subcutaneous area, and soft tissue fascia may be destroyed

REFER: Suspect inhalation injury if facial burns, electrical burns, or burns on cartilaginous areas such as the nose and ears (cartilage will not regenerate); also suspect if burns are on >10% of body, are circumferential (risk of compartment syndrome) and cross major joints

Question 136

Total percentage of Body Surface Area
1. Rule of Nines: Child
2. Rule of Nines: Adults

Answer 136

1. Arms: 9% each
   Legs: 14% each
   Trunk: 18% anterior trunk, 18% posterior trunk
2. Arms: 9% each
   Legs/trunk: 18% each leg, anterior trunk, and posterior trunk

Question 137

Criteria for Burn Center Referral

Answer 137

• Burns involving face, hands, feet, genitals, major joints
• Electrical burns, lightning burns
• Partial-thickness burns >10% TBSA
• Third-degree burn in any age group

Question 138

Bioterrorism: Anthrax
1. Definition
2. Clinical Presentation
3. Treatment

Answer 138

1. Infection caused by Bacillus Anthracis (gram+ rods)
   3 TYPES of anthrax: cutaneous, GI, and pulmonary
2. Cutaneous: begins as papule that enlarges in 24-48 hrs and develops eschar (necrosis) and ulcerations; lesion usually on arms, neck, or face
   - Check for hx of exposure or handling animals, hides, hair, or wool

Pulmonary anthrax (inhalational anthrax): inhaling aerosolized spores through 1) working with animals, wool, or animal hides/hair or 2) bioterrorism
- Fulminant inhalational anthrax → death within days
- Symptoms are flu-like and associated w/ cough, chest pain w/ cough, hemoptysis, dyspnea, hypoxia, and shock

3. • Cutaneous anthrax (naturally acquired): Doxycycline BID, ciprofloxacin BID, levofloxacin BID x 7-10 days (if bioterrorism suspected, treat for 60 days)
     - Without treatment, 20% of people w/ cutaneous anthrax may die; mortality rate for pulmonary anthrax w/out treatment is 90%
     - Postexposure prophylaxis (bioterrorism suspected): Doxycycline 100 mg PO BID x 60 days
     - Pathogens that have high mortality rates are easily spread and are airborne (i.e., aerosolized route) can be used for bioterrorism

• High risk pathogens: Anthrax bacilli (Bacillus anthracis), smallpox virus, botulism (Clostridium botulinum), plague (Yersinia pestis), viral hemorrhagic fevers (Ebola, Marburg)

Question 139

Smallpox (Variola Virus)
1. Definition
2. Clinical Presentation
3. Treatment

Answer 139

1. Infection targets respiratory and oropharyngeal mucosal surfaces
   - “Eliminated” in 1977
   - Incubation period: 2 weeks
   - Mortality rate: 20-50%
2. • Flu-like symptoms
     - Numerous large nodules appear mostly in center of face and on arms & legs
3. First antiviral approved: tecovirimat (Tpoxx)
   - If vaccine is given within 2-3 days postexposure, it can lessen severity of illness
   - Vaccinia immune globulin (e.g., for pregnant, immunosuppressed) available

Question 140

Difference b/t contact dermatitis and atopic dermatitis

Answer 140

Best clue: unilateral location and shape of lesions in contact dermatitis

Question 141

Preferred antibiotic for human, dog, and cat bites:

Answer 141

amoxicillin-clavulanate (Augmentin)

Question 142

MRSA infection: if pt is allergic to bactrim, which antibiotic should you use?

Answer 142

Doxycycline or minocycline or clindamycin

Question 143

Anthrax prophylaxis

Answer 143

Postexposure prophylaxis: Doxycycline 100 mg PO BID x 60 days

Question 144

Tx for adult on recluse spider bite:

Answer 144

• Antibiotic on wound
• Cold packs
• Nsaids

Question 145

For moderate acne on 2 prescrip9tion topicals who is not responding to treatment, what is your next step:

Answer 145

Add minocycline, tetracycline, or doxycycline.

Acne causation includes; androgens (hormones), bacteria (cutibacterium acnes), genetics, and possibly diet

Question 146

Example of an antimetabolite or disease-modifying antirheumatic drug (DMARD)

Answer 146

methotrexate

Question 147

How is mild acne treated?

Answer 147

Only with topicals

Question 148

What is the hallmark pattern found in pityriasis rosacea?

Answer 148

“herald patch” or “Christmas tree” pattern

Question 149

PHN prophylaxis:

Answer 149

Use TCAs (amitripyline [Elavil])

Question 150

What is trephination? What does it treat?

Answer 150

Straighten one end of a large paper clip or 18g needle and heat it with a flame, then gently drill down the nail until blood seeps out

Subungual hematoma

Question 151

What does the FDA recommend regarding oral antifungals for fungal skin and nail infections?

Answer 151

Avoid prescribing oral ketoconazole (Nizoral PO) for fungal skin and nail infections because the harm (e.g., serious liver damage) outweighs the benefit. Topical ketoconazole shampoo is safe.

Question 152

What should pt use for rashes near the eys?

Answer 152

Ophthalmic-grade sterile cream and ointments

Question 153

Which pts are at higher risk for developing postglomerular nephritis?

Answer 153

Scarlet fever (compared with “strep” throat)

Question 154

Pts on anti-TNF are at a higher risk for what?

Answer 154

• Melanoma
• SCC

Question 155

Wounds
1. Definition
2. Stages & Healing Event

Answer 155

1. A disruption or damage to the skin. Four phases involved.
   - Some factors impairing wound-healing process are older/mature age, poor nutrition, impaired immune system, impaired mobility, stress (affects immune system), diabetes, certain medicines (drugs that impair clot formation,s teroids), pressure loading, cigarette smoking, and 2º bacterial infection
2. Phases of Wound Healing
   - Hemostasis → Constriction of local blood vessels, platelet aggregation, fibrin (clot) formation
   - Inflammation → Macrophages and lymphocytes proliferate, presence of inflammatory mediators such as cytokines and leukotrienes
   - Proliferation → Proliferation of basal and epithelial cells (angiogenesis)
   - Remodeling → Remodeling of collagen, scar formation (cicatrix)

Question 156

Categories of Wound Healing
1. Primary healing (primary closure)
2. Secondary intention
3. Tertiary intention (delayed primary closure)

Answer 156

1. Wound is closed within 24 hrs by suturing or applying tissue glue or butterfly strips (so wound edges are well approximated); causes least amount of scarring
2. Would is left open with formation of granulation tissue and scarring; wound heals from bottom of the wound up; wound edges are not well approximated; causes more scarring than primary closure
3. Wounds with heavy contamination or poor vascularity (crush injuries) are best left open to heal by secondary intention (granulation) and wound contraction → wound edges approximated in 3-4 days; produces the most scar tissue

Question 157

High-Risk Wounds that may warrant Referral

Answer 157

• Infected wounds (pus is present, wound not healing, devitalized tissue, wound becomes hot and swollen)
• Closed-fist injuries → Refer to ED or urgent care, esp if join is involved (septic joint)
• Facial wounds w/ risk of cosmetic damage (e.g., large wound, bites, cartilage injury)
• Suspected foreign body or embedded object in wound that cannot be removed
• injury to a joint capsule; if joint capsule penetrated, joint can become infected
• electrical injuries
• paint-gun or high-pressure wounds
• Chemical wounds (esp alkali-related damage) of the eyes or skin
• Suspected physical or child abuse
• Wounds with cosmetic concerns (cartilage wounds in the ears, nose); cartilage does not heal → Refer to plastic or ED

Question 158

Infected Wounds - General treatment

Answer 158

• Do not suture infected wounds (open >24 hours); infected wounds will heal by secondary intention

Mild cellulitis:
- Without abscess: treat w/ abx → cdephalexin (keflex) 250 mg QID or 500 mg BID, dicloxacillin (Dynapen) 500 mg Q6H x 10 days
- if PCN allergy → azithromycin or clarithromycin (Biaxin)
- With abscess, treat for MRSA: culture purulent wounds and follow up in 48 hours → give trimethoprim-sulfamethoxazole (bactrim DS) BID, doxycycline, or minocycline BID x 10 days

Severe cellulitis or if systemic symptoms (fevers) or if diabetic (or immunocompromised) → hospitalize for treatment with systemic antibiotics

Question 159

Closed-fist Injuries and Bite Wounds - General Treatment

Answer 159

• Refer closed-fist injuries to ED or urgent care
• Xray of hand to r/u foreign body (i.e. teeth) and fracture
• Sometimes US is used to view foreign bodies that do not show up on xrays
• Test distal pulses, skin color, ROM, tendon damage, nerve damage, and fracture
• Do not suture bite wounds or puncture wounds d/t high risk of infection
• Antibiotic prophylaxis is required for animal and human bite wounds
• First line: amoxicillin-0clavulanic acid (Augmentin PO BID x 10 day)
• Tetanus vaccine required if last dose wad >5 years ago
• Use Tdap vaccine (tetanus, diphtheria, and acellular pertussis, if never had Tdap) in pt >7 yo

Question 160

Retained Foreign Bodies - General Treatment

Answer 160

• Higher risk of infection; if unable to remove or locate in high-risk area → Refer to ED
• First-line imaging: Plain Xray
• US used if suspected object or object does not show on xrays (radiolucent)
• may not be visible on xrays: small glass splinters or particles, splinters, thorns, fish bones, plastics

Question 161

Minor Burns (Superficial- and Partial-Thickness): General treatment

Answer 161

• Wash area with water and mild soap
• using sterile tongue blade, apply thin layer of 1% silver sulfadiazine (Silvadene) to burned area
• cover burned are w/ nonstick gauze (e.g. Telfa). Secure w/ stretch-conforming gauze (e.g., Kerlix)
• Apply Silvadene once to BID until burn is healed. after healed, consider using Desitin daily for 1-2 wks to protect area from sunlight. Do not expose recently healed burned skin to sunlight (causes hyperpigmentation)

NOTE: Silver sulfadiazine is contraindicated if pt has sulfa allergies. Do not apply to face (will stain). If facial burns, use triple antibiotic or mupirocin (Bacroban) ointment.

Question 162

Wound Care - General Principles

Answer 162

• During hx, ask about mechanism 9of injury and other details about the incident
• Check for allergy to iodine, rubber, latex, or lidocaine. If pt has rubber or latex allergy, do NOT use latex gloves, use silicone-based disposable gloves
• Remember tetanus prophylaxis; if last dose was >5 years ago, give Tdap booster
• Irrigate wound w/ NS (do not mix w/ Betadine, hydrogen peroxide,n Hibiclens) and/or wash area w/ mild soap and water; remove dirt
• Assess wound for neurovascular and tendon damage. Check distal pulses. Check ROM. Check sensation (sharp and dull). Depending on injury, r/o foreign body
• Specific treatment depends on type of wound and pt characteristics

Question 163

Primary Care Practice: Procedures
Informed Consent

Answer 163

Informed consent should be obtained (verbal or written) prior to performing any procedure. Discuss the benefits and risks of the procedure, including bleeding risk, infection, scarring, depigmentation, damage to underlying structures (e.g., blood vessels, nerves), recurrence, or incomplete treatment of the lesion

Question 164

PCP: Procedures → Local Anesthesia
1. Types of lidocaine
2. Drugs
3. Contraindications
4. Adverse Complications
5. Examples of use

Answer 164

1. Two types of lidocaine 1%: plain or mixed with epinephrine
   - Do not use lidocaine w/ epinephrine on areas of the body at high risk of ischemia (tip of nose, ears, fingertips, toes, penis)
2. Drugs:
   - Lidocaine 1% (plain) onset of action is 2-5 min
   - Duration of action: 30 min - 2 hours
   - Advised pt of burning sensation at start of injection; this will disappear
3. • Do not give if an infected injection site
     - allergy to anesthetic
     - devascularized/ischemic tissue damage
4. • Complications may arise if pt has allergic reaction or infection
     - solution is injected directly into blood vessel
     - injury to nerves and tendons in area
5. • Use for wounds that need suturing, incisions (e.g., embedded splinter or paronychia) and, biopsy

Question 165

Digital Nerve Block (Fingers): Instructions

Answer 165

1. Clean web space on each side of involved finger w/ alcohol or betadine swab and allow to dry
2. Draw up ~3 L of plain lidocaine 1% from vial using a 5- to 10-mL syringe w/ an 18g needle. Then change needle to smaller gauge (25- to 30-gauge, 1 1/2 inches)
3. Place needle in perpendicular position above w3eb space and insert into subcutaneous tissue space
4. Before injecting, aspirate first to check for placement. If no blood, slowly inject lidocaine into web space (volar aspect). Inject slowly and use small amounts
5. If blood is aspirated, withdraw needle slightly and reposition slightly (without removing needle from skin)
6. Reposition needle slightly and continue to infiltrate drug into web space on each side of injured finger
7. Instruct pt that it may take 15 mins for anesthesia to become effective. Ask pt if area is numb (test by using tip of needle to test sensation) before suturing

Question 166

Infiltration Technique

Answer 166

1. Apply Betadine on intact skin around wound
2. Slowly insert syringe (as directed above) into subcutaneous layer only and aspirate for blood
3. Slowly infiltrate the edges of the wound, then withdraw slightly to move it to another area. The amount of lidocaine that is used varies based on size of wound and location

Question 167

Suturing: General Rules

Answer 167

• Do not suture puncture wounds or human or animal bites
• Do not suture heavily contaminated wounds
• Lacerations >12 hours old are at higher risk for infection. Do not suture infected wounds
• Do not suture wounds that have been open >24 hours (high bacterial load)

Question 168

Types of Sutures and Needles
Example: Skin laceration

Answer 168

• Use nonabsorbable synthetic suture (i.e. nylon, prolene)
• Preferred needle type of suture skin is a curved cutting needle
• Suture size: The US Pharmacopeia (USP) classified suture by diameter size w/ ↓ diameters correlated to ↓ USP sizes
• Suture sizes smaller than 0 are denoted w/ ↑ # of 0s. The ↑ the # of 0s (e..g, 5-0 is = 00000), the smaller the diameter. Suture sizes range from 10 to 12-0; the smallest diameter suture used in human surgery is 11-0 (about the size of human hair) and is used to repair small blood vessels. The preferred suture size for a skin laceration repair is 3-0 to 5-0.

Question 169

Suture Placement

Answer 169

1. Evert the edges of the wound by inserting needle at 90º angle (ensures that wound edges are well approximated)
2. Use needle holder to hold needle; use forceps to grab wound edges
3. Usually, simple sutures are used on skin lacerations. Each suture is individually tied, then cut (simple interrupted sutures)
   When cutting suture thread, do not cut too short, leave a shorttail (easier to remove)
4. Nonabsorbable synthetic sutures are preferred for lacerations/wounds of skin
5. if suturing scalp of a person w/ black hair, blue-colored suture thread is easier to visualize (for removal)

NOTE: Do NOT suture deep puncture wounds, animal bites (except if cosmetic area like the face), or actively bleeding wounds (will form a subcutaneous hematoma). Control bleeding first, esp. arterial bleeds

Question 170

Suture Removal: General Guidelines
- When to remove sutures for the following: face, scalp, upper extremities, lower extremities

Answer 170

Most sutures are removed within 7-10 days. Stitcujes that are left beyond 10 days may develop scars that resemble a “railroad track.” Use forceps and lift suture from the skin. Cut suture with scissors. Use forceps to grasp the knot and pull the suture gently out of the wound.
- Face: 5-7 days
- Scalp: 7-10 days
- UE: 7-10 days
- LE: 10-14 days

Question 171

Skin Biopsy: Punch Biopsy
Definition/HPI/PE

Answer 171

• Check for hx of bleeding ds and use of drugs that affect bleeding time (aspirin, warfarin). pt with INR >2.5 should not be biopsied
• Check scar history (e.g hx of keloids or hypertrophic scarring)
• Refer to dermatologist for facial biopsies, biopsy of areas w/ cartilage, suspected melanoma, hx of keloid/hypertrophic scarring, bleeding ds, and the like
• Ask whether pt is allergic to lidocaine or rubber/latex (use silicone)glovees)

Question 172

Skin Biopsy: Punch Biopsy
Procedure

Answer 172

1. “Prep” skin site w/ alcohol wipes and allow to dry
2. Using a tuberculin syuringe, draw lidocane 1% and epinephrine 1:100 (do not use w/ epinephrine if area is on the nose, ears, fingertips, toes, penis)
3. Inject slowly under the spidermis until a small bleb is formed. The color of the skin over the bnleb area becomes paler d/t vasoconstricting effect of epinephrine
4. Check site for numbness by using the point of the syringe and testing sensation on the bleb area. The skin will become nujmb within 5-10 mins (lasts about 45-60 mins)
5. Using a 3-mm skin punch, position instrument at 90º (perpendicular to the skin)
6. Twist the punch instrument gently using a “drilling” motion until it has pierced the epidermis (there should be about 1/2 inch of the blade visible on top of the skin)
7. Remove from skin and lift plug gently with forceps (do not crush). Use a scalpel to cut the plug at the base. Immediately place it on the biopsy specimen container. Do not forget to lavel the specimen cup w/ the patient’s name, location of the biopsy site, and type of tissue obtained
8. Cover area w/ sterile 2x2 gauze w/ tape (if bleeding) or w adhesive bandage if minimal bleeding. Instruct pt to change bandage once daily
9. Instruft pt ti keep site dry. Ismtruct to avoid submerging site in water (avoid bath tubs, swimming, hot tubs) until it is healed. Site will scab within a few days

Question 173

Cryotherapy (Cryosurgery)
1. Definition
2. Contraindications

Answer 173

1. • Cryotherapy causes ice crystals to form inside the cells and destroys them; rarely requires anesthesia. There are several methods that can be used such as open sprays, dipstick, contact, and tweezer technique
     - Expected outcome is blistering of treated are w. the first 12-24 hr and crusting. Blistered skin will shed and a shallow ulcer will be left; will heal within a few days
2. • Area has impaired circulation and/or neuropathy, open wounds, cold hypersensitivity (Raynaud’s phenomenon, cold urticaria, cryobulinemia, and paroxysmal cold hemoglobinuria), angina, or severe cardiac disease
     - Certain locations should be avoided:
     - eye area, vermilion border of lip, nail matrix, and areas w/ cartilage
     - an adverse effect is hypopigmentation although darker-skinned individuals can develop hyperpigmentation
     - other effects: scarring, alopecia, tissue distortion