Common Skin Disorders and Infections Flashcards

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1
Q

Name the followng skin conditions in each category:

  1. Acneiform lesions? 2
  2. Bacterial infections? 5 3. Pigmented lesions? 5
  3. Dermatophyte infections? 5
  4. Exanthems associated with systemic infections? 4
  5. Miscellaneous? 3
A

1.

  • Acne vulgaris
  • Rosacea

2.

  • Folliculitis
  • Pseudobarbae folliculitis
  • Furuncles
  • Carbuncles
  • Impetigo

3.

  • Moles
  • Solar lentigo
  • Seborrheic keratosis
  • Actinic keratosis
  • melasma

4.

  • Tinea capitis
  • Tinea corporis
  • Tinea pedis
  • Tinea cruris
  • Tinea versicolor (Pityriasis)

5.

  • Fifth’s disease
  • Hand-foot-mouth disease
  • Scarlatinia
  • Roseola

6.

  • Miliaria (Heat rash)
  • Skin tags
  • Corns and callouses
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2
Q

ACNE VULGARIS

  1. Is what?
  2. Menifest how? 3
A
  1. Inflammation of pilosebaceous units of certain body parts
    - Occur most frequently in adolescence
  2. Manifest as
    - comedones,
    - papulopustules, or
    - nodules plus cyst
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3
Q

ACNE VULGARIS

  1. Pathogenesis: Disease of what?
  2. 4 factors involved?
A
  1. Disease of pilosebaceous follicles
  2. 4 factors involved
    - Follicular hyperkeratinization
    - Increased sebum production
    - Propionibacterium acnes within the follicle
    - Inflamation
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4
Q

What are the four steps that create a blemish?

A
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5
Q

Acne vulgaris: Clinical presentation? 3

A
  1. Lesions on the skin
  2. Pain in lesions
  3. Skin lesions include:
    - Comedones
    - Papules and papulopustules
    - Nodules
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6
Q

Describe the 6 stages of acne

A
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7
Q

Acne grades

Describe Grades I (1) II (3) III (3) IV (3)

A

Acne grades

  1. Grade I
    - Minimal blackheads and a few papules
  2. Grade II
    - 10 or more
    - Blackheads, papules, pustules
    - Redness and inflammation
  3. Grade III
    - 15-20+
    - Blackheads, papules, pustules
    - Redness and inflammation
  4. Grade IV
    - Severe case
    - Extreme amount of pustules
    - Extreme edema
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8
Q

Acne Vulgaris is dx how?

Female patients with dysmenorrhea or hirsutism: What labs? 4

A
  1. Diagnosis

Clinical

  1. Female patients with dysmenorrhea or hirsutism
    - Total/Free testosterone
    - DHEA-S
    - LH
    - FSH
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9
Q

ACNE VULGARIS

Treatment

OTC? 2

Topical Retinoids? 3

Topical antibiotics (2nd line)? 2

Oral therapies? 2

Oral isotretinoin? 2

A

OTC

  1. Benzoyl peroxide
  2. Salicylic acid

Topical retinoids (first line)

  1. Adapalene (Differin): best tolerated
  2. Tretinoin (Retin-A)
  3. Tazarotene (Tazorac)

Topical antibiotics (2nd line)

  1. Clindmycin
  2. Erythromycin

Orall therapies?

  1. Doxycycline
  2. Minocycline (Minocin)

Oral isotretinoin

  1. For sever treatment failure
  2. Must register in the iPLEDGE program before using
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10
Q

What is Rosacea?

Epidemiology: Age and Gender?

A
  1. Chronic acneform disorder of facial poilosebaceous units
    - Increased reactivity of capillaries to heat
  2. Epidemiology

Onset at 30-50 years old

Females predominantly

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11
Q

Rosacea

  1. Exacerbating factors? 4
  2. Clinical Presentation? 2
A
  1. Exacerbating factors
    - Hot liquids
    - Spicy foods
    - Alcohol
    - Exposure to sun and heat
  2. Clinical presentation
    - Redness to the cheeks, nose, and chin
    - Burning or stinging with episodes
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12
Q

4 subtypes of Rosacea?

A
  1. Erythematotelangiectatic rosacea
  2. Papulopustular rosacea
  3. Phymatous rosacea
  4. Ocular rosacea
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13
Q

Rosacea Treatment

3

A
  1. Minimize precipitating factors
  2. Topical antibiotics are first line therapy for mild to moderate patient (typically without papules or pustules)
  3. Systemic antibiotics-moderate to severe symptoms (papules, pustules, or ocular involvement)
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14
Q

Rosacea: Topical antibiotics are first line therapy for mild to moderate patient (typically without papules or pustules). Which are they? 5

A
  1. Azelaic Acid (gel or cream) apply BID
  2. Metronidazole - 0.75% apply daily (cream or gel)
  3. Erythromycin (cream) apply thin layer bid
  4. Clindamycin (gel or solution) apply bid
  5. Brimonidine (gel) applied once a day
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15
Q

Rosacea: Systemic antibiotics-moderate to severe symptoms (papules, pustules, or ocular involvement)? 3

A
  1. Tetracycline 250-1000mg per day
  2. Doxycycline/Minocycline 100-200 mg per day
  3. Erythromycin 250-500mg qid
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16
Q

ROSACEA

Other treatment considerations

  1. Laser treatment can be helpful for what?
  2. Pulsed-light therapy can be helpful for what?
  3. What other two treatments may be helpful?
A
  1. telangiectasias
  2. facial erythema
  3. Cleansers and Photodynamic therapy
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17
Q

Complications of Rosacea? 4

A
  1. Eye involvement
  2. Gram negative folliculitis
  3. Permanent telangiectasias
  4. Rhinophyma
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18
Q

RHINOPHYMA

is what?

A

Soft tissue hypertrophy related to vasodilatation (Not well understood)

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19
Q

FOLLICULITIS

  1. What is it?
  2. Most common bug?
  3. Hot tub folliculitis is caused by what?
  4. Can also be caused by what but this is the exception to the rue?
A
  1. Infection of the hair follicles
  2. Most common pathogen Staphylococcus Aureus
  3. “Hot tub” folliculitis caused by Pseudomonas
  4. Can be caused by yeast, but this is the exception to the rule
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20
Q

FOLLICULITIS symtpoms? 3

A
  1. Looks like red pimples with a hair in the center
  2. May itch or burn
  3. “Hot tub” folliculitis appears about 72 after
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21
Q

Folliculitis treatment? 4

A
  1. Warm compresses 3 times daily
  2. Shaving should be avoided in involved areas
  3. Topical antibiotics such as Mupirocin (Bactroban)
  4. Recent research shows systemic antibiotics to be of no benefit.
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22
Q

FOLLICULITIS

Some principles

  1. Recurrent folliculitis is associated with what?
  2. ____________ used on anterior nares bid for 2-5 days once monthly decreases frequency
  3. What may predispose a patient to candida folliculitis? 3
A
  1. nasal carriage of S. Aureus
  2. (Bactroban (Mupirocin)

3.

  • Antibiotic therapy,
  • corticosteroid therapy, and
  • immunosuppression
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23
Q
  1. PSEUDOBARBAE FOLLICULITIS is what? ( Otherwise known as what?)
  2. Very common in who?
  3. Occurs when free ends of tightly coiled hairs reenter skin and cause a what?
  4. What do they look like?
  5. Diagnosis is made based on what?
A

1. Otherwise known as “razor bumps”

2. Very common in African Americans

3. a foreign body inflammatory response

4. Firm papules with embedded hair

5. Diagnosis is made based on clinical appearance

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24
Q

PSEUDOBARBAE FOLLICULITIS

Treatment? 5

A
  1. Most effective and safe is stop shaving (first line)
  2. Laser hair removal

Adjunctive medical therapy

  1. Topical retinoids (tretinoin)
  2. Low potency corticosteroids (treat only for 3-4 weeks)
  3. Topical antimicrobials (benzoyl peroxide 5% or clindamycin 1%)
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25
Q

What are furuncles?

  1. What are a cluster of furnuncles?
  2. May progress from an erythematous lesion to a fluctuant lesion after __days
  3. Lesion may rupture spontaneously (What are extruded)?
A
  1. Furuncles (boils)
    - skin abscesses caused by staphylococcal infection of a hair follicle
  2. Carbuncles are a cluster of furuncles
  3. 4
  4. pus and necrotic tissue
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26
Q

FURUNCLES/CARBUNCLES

  1. Common areas include? 5
  2. Predisposing factors include? 4
A
  1. Common areas include
    - buttocks,
    - axillae,
    - neck,
    - face, and
    - waist
  2. Predisposing factors include
    - diabetes,
    - malnutrition,
    - obesity, and
    - hematologic disorders
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27
Q

FURUNCLES/CARBUNCLES

  1. Treatment? 2
  2. What may be necessary to do with the wound?
  3. What will you need if if constitutional symptoms or concomitant cellulitis > 5cm?
A

1.

  • Hot compresses to enhance drainage
  • Fluctuant lesions benefit from I&D
    2. Packing of the wound may be necessary
    3. System antibiotics if constitutional symptoms or concomitant cellulitis > 5cm
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28
Q

FURUNCLES/CARBUNCLES

System antibiotics if constitutional symptoms or concomitant cellulitis > 5cm. Which ones? 3

A
  1. Bactrim 1-2 tabs BID x 10 days
  2. Clindamycin and
  3. Cephalexin [Keflex] very effective against most staph and strep species
29
Q

Impetigo

  1. Usually caused by what bugs?
  2. What do the lesions start as?
  3. What do they progress to?
  4. Sores usually appear in what areas?
  5. Treatment of choice? 2
A

Contagious infection

  1. usually caused by staphylococcal or streptococcal bacteria
  2. Red lesions that can break open, ooze
  3. Develop a yellow-brown crust (honey colored)
  4. Sores usually appear around the mouth and nose.
  5. Topical antibiotic 2% ointment/cream (Bactroban) is the main treatment,
    - although oral antibiotics may be needed in severe cases.
30
Q

Describe a mole

A

Well defined borders

Uniform in color

Usually brown or black, moles can be anywhere on the body, alone or in groups, and generally appear before age 20.

31
Q

How can moles change over the years? 3

A

Some moles change slowly over the years:

  1. Becoming
    - raised,
    - developing hair, and/or
    - changing color

While most are non-cancerous, some moles have a higher risk of becoming cancerous.

32
Q

Describe the Clinical characteristics and histology of the followig moles:

  1. Junctional nevus
  2. Compound nevus
  3. Intradermal nevus
  4. Halo nevus
  5. Blue nevus
A
33
Q
  1. Moles Dx?
  2. What would make you concerned? 3
  3. Rx?
A

Diagnosis

  1. Biopsy
    - ABCDE

Certain characteristics of concern

  1. If mole becomes itchy, bleeds or ulcerates
  2. Treatment

Removed with shaving or excision

34
Q

SOLAR LENTIGO

  1. What is it?
  2. What do you get them from?
  3. Treatment? 4
A
  1. Solar lentigos are flat, brown areas of skin that can be up to one inch in diameter. They are benign and painless.
  2. Sun exposure- Areas that get a lot of sun; such as the face, hands, and arms.
  3. Treatment
    - Cryotherapy (first line)
    - Tretinoin cream or hydroquinone cream (lighten)
    - Triple combination cream
    - Bleaching solutions and chemical peels
35
Q

What are the triple combination creams that you would use with solar lentigo?

3

A
  • Fluocinolone acetonide 0.01%
  • Hydroquinone 4%
  • Tretinoin 0.05%
36
Q
  1. What is seborrheic keratosis?
  2. How may they present? 2
  3. Usually appear in what deecade of life?
A
  1. Common, multiple, benign skin lesion commonly found on the torso
  2. A person may have an isolated lesion or hundreds of lesions
  3. Usually appear in the 4th and 5th decade of life

Uncommon in people under 30 y/o

37
Q

SEBORRHEIC KERATOSIS

clinical manifestations?

4

A
  1. Well-circumscribed gray-brown-to-black plaques with a “stuck-on” appearance
  2. Warty
  3. often scaly
  4. hyperpigmented lesion
38
Q

SEBORRHEIC KERATOSIS

Do not require treatment unless causing discomfort or for cosmetic reasons.

Treatments includes? 5

A
  1. Cryotherapy
  2. Curettage & Cautery
  3. Laser surgery
  4. Shave biopsy
  5. Send any suspicious looking lesions for pathology
39
Q
  1. ACTINIC KERATOSIS (AKs) is what?
  2. Occurs in what areas of the body?
  3. More common in what individuals?
  4. Symtpoms? 4
A
  1. Rough, dry, scaly patch or growth that forms on the skin
  2. Extremely common, occurs in sun exposed areas
  3. More common in fair-skinned individuals
  4. Symptoms
    - Rough feeling patch on skin
    - Rough patch that feels painful when rubbed
    - Itching or burning
    - Lips feel constantly dry
40
Q

ACTINIC KERATOSIS

Causes? 2

60% of what arise from AKs!?

A
  1. Sun exposure
  2. Tanning beds

squamous cell carcinomas

41
Q

ACTINIC KERATOSIS

  1. Prevention?

2

A

Prevention

  1. No sun exposure
  2. Using sunscreens reduces development of AKs

SPF 15 or higher every day

Extended outdoor activity 30SPF or higher

42
Q

ACTINIC KERATOSIS

Treatment:

  1. Nonhypertrophic AKs?
  2. Hypertrophic AKs?
  3. Multiple AKs?
A
  1. Liquid nitrogen cryotherapy (most common used)
  2. Surgical curettage (send these to path)
  3. Topical 5-fluorouracil 5-FU (Efudex) or imiquimod (Aldara) are effective
43
Q
  1. MELASMA aka?
  2. What is it?
  3. Melasma occurs in what % of pregnant women?
  4. More often in women with what?
  5. Triggers? 3
A
  1. (PREGNANCY MASK)
  2. Tan or brown patches on the cheeks, nose, forehead, and chin.
  3. Melasma occurs in half of all women during pregnancy.
  4. More often in women and people with darker skin
  5. Triggers
    - Sun exposure
    - Change in hormones
    - Cosmetics
44
Q

MELASMA

Dx? 2

Rx? 3

A
  1. Diagnosis
    - Clinical
    - Biopsy
  2. Treatment
    - Will usually go away on own
    - Hydroquinone (first line)
    - Tretinion and corticosteroids (second line)
45
Q
  1. TINEA (RINGWORM) is what?
  2. There are various forms named after their location? 5
A
  1. Tinea is a dermatophytosis that is a superficial fungal infection caused by dermatophytes, most commonly Tricophyton rubrum.
  2. There are various forms named after their location:
    - Capitis
    - Corporis
    - Pedis
    - Cruris
    - Versicolor
46
Q
  1. TINEA CAPITIS is what?
  2. Dx? 3
  3. Rx? 2
A
  1. Gradual appearance of round patches of dry scale, alopecia, or both
  2. Diagnosis
    - Clinical
    - Wet mount
    - Woods lamp
  3. Treatment
    - Oral antifungals
    - Selenium sulfide shampoo
47
Q

TINEA CAPITIS

What oral antifungals would you use for kids?

Adults?

A

Griseofulvin (kids)

Terbinafine (adults)

48
Q
  1. What is tinea corporis?
  2. aka?
  3. Causes?
  4. Treatment:
    - MIld to Moderate?
    - Extensive or resistant lesions?
A
  1. Dermatophytosis that causes pink-to-red O-shaped patches and plaques
  2. Ringworm
  3. Causes
    - T. rubrum
  4. Treatment
    - Mild to moderate lesions

Imidazole bid

-Extensive or resistant lesions

Oral itraconazole 200mg q/day 2-3 weeks

49
Q

TINEA PEDIS (ATHLETE’S FOOT)

4 clinical forms?

A

Most common dermatophytosis

4 clinical forms

  • Chronic hyperkeratotic
  • Chronic intertriginous
  • Acute ulcerative
  • Vesiculobullous
50
Q

Tinea Pedis

Rx?

3

A

Topical and oral antifungals

Oral

  1. Itraconazole 200mg

Moisture reduction and drying agents

Drying agents

  1. Miconazole powder
  2. Burow solution soaks
51
Q
  1. Tinea Cruris aka?
  2. Risk factors? 3
  3. What do the lesions look like?
  4. Treatment? 2
A
  1. Jock Itch
  2. Risk factors
    - Warm weather
    - Wet restrictive clothing
    - Obesity
  3. Lesions are pruritic ringed lesions that extend from crural fold over adjacent upper thigh
  4. Treatment

Topical antifungal (cream, lotion, gel)

  • Clotrimazole
  • Ketoconazole
52
Q
  1. TINEA VERSICOLOR aka?
  2. Caused by what fungus?
  3. Manifest how?
  4. Risk factors? 4
A
  1. Pityriasis
  2. Skin infection from Malassezia furfur
  3. Manifest as multiple asymptomatic scaly patches varying in color
  4. Risk factors
    - Heat & humidity
    - Pregnancy
    - Diabetes
    - undernutrition
53
Q

Tinea Versicolor

  • Presentation? 2
  • Diagnosis? 2
A

Presentation

  1. Usually asymptomatic
  2. Appearance of multiple tan, brown, salmon, pink, or white scaling patches

Dx?

  1. Potassium hydroxide wet mount (Indentification of hyphae and budding cells (“spaghetti and meatballs”))
  2. Woods lamp
54
Q

Tinea versicolor Treatment:

  • Topical antifungal? 2
  • Oral antifungals? 2
A
  1. Topical antifungal
    - Slenium sulfide shampoo
    - Ketoconazole
  2. Oral antifungals
    - Ketoconazole
    - fluconazole
55
Q

TINEA FINDINGS

S and S? 3

Labs? 3

A

S/Sx’s:

  1. Pruritus
  2. Annular, scaly plaques with raised erythematous edges
  3. Central Clearing

Labs:

  1. KOH prep specimen will show hyphae
  2. Wood’s lamp = a brilliant silver-blue fluorescence of infected hair
  3. Culture (on Sabouraud’s medium)
56
Q

Fifth’s disease

  1. Caused by what?
  2. Aka?
  3. Medical name is what?
  4. Affects what age of children?
  5. Spread with what? 2
A
  1. Caused by human parvovirus B19
  2. Also called “slapped cheek disease”
  3. Medical name is erythema infectiosum
  4. Affects children 5-7 y/o
  5. Spread by contact with saliva or mucus
57
Q

Presentation of 5th’s disease

2

When does the rash usually go away?

A

Presentation

  1. Bright red raised rash on the face, then arms, legs and trunk
  2. Flu-like symptoms
    - Rash usually goes away within 2 weeks, fades from the center -outward causing a blotchy or “lacy” look
58
Q

Fifth’s Dz treatment? 1

Complications?

A
  1. Treatment

NSAIDS for symptomatic relief

  1. Complications

Pregnancy

Can cause the baby to develop severe anemia and miscarriage or stillbirth

59
Q

HAND-FOOT-MOUTH DISEASE

  1. Caused by what?
  2. This common, contagious childhood illness starts with a what? 3
  3. It spreads through what vectors? 2
  4. Treatment?
A
  1. Coxsackie virus A16
  2. This common, contagious childhood illness starts with a
    - Fever
    - Painful mouth sores
    - Non-pruritic rash with blisters on hands, feet, and sometimes buttocks and legs that follow
  3. It spreads through coughing, sneezing, so wash hands often when dealing with coxsackie.
  4. Home treatment includes ibuprofen or acetaminophen (do not give aspirin to children) and fluids. It will typically resolve in 7-10 days.
60
Q

SCARLATINA (SCARLET FEVER)

  1. Scarlet fever is caused by an infection with what?
  2. It has a characteristic rash, which appears how? 5
  3. How long will the rash last?
A
  1. group A streptococcus bacteria.

2.

  • fine, red, and rough-textured
  • appears 12–48 hours after the fever
  • generally starts on the chest, armpits, and behind the ears
  • spares the face
  • Swollen red tongue (strawberry tongue)
    3. The rash can last for more than a week
61
Q

SCARLATINA (SCARLET FEVER)

  1. If left untreated what may it lead to?4
  2. First line?
  3. Second line?
A
  1. If left untreated may progress to rheumatic fever, glomerulonephritis, meningitis and pneumonia
  2. First-line treatment is

Penicillin

  1. Second-line

First-generation cephalosporin

62
Q

ROSEOLA (ROSEOLA INFANTUM)

  1. What is it?
  2. Most common in what ages?
  3. Rare after what?
  4. Presentation?
  5. What follows the initial presentation?
  6. Treatment?
A
  1. A mild, contagious illness
  2. Most common in children age 6 months to 3 years
  3. Rare after age 4
  4. The symptoms are respiratory illness, followed by a high fever (which can trigger seizures) for 3-5 days
  5. Fevers abruptly end and are followed by a rash of small, pink, flat, or slightly raised bumps on the trunk–then the extremities
  6. Treatment is supportive.
63
Q
  1. What is heat rash also called?
  2. Looks like what?
  3. Treatment?
  4. Where does the rash appear? 3
  5. Often happens how?
  6. How should a baby dress?
A
  1. The result of blocked sweat ducts
  2. Looks like small red or pink pimples.
  3. Benign and does require treatment.
  4. Appearing over an infant’s head, neck, and shoulders,
  5. The rash is often caused when well-meaning parents dress babies too warmly, but it can happen to any infant in very hot weather
  6. A baby should be dressed as lightly as an adult who is resting
64
Q

Heat rash most likely to appear where? 5

Treatment? 2

A

Most likely to appear in :

  1. Neck
  2. Groin
  3. Underneath the breasts
  4. In creases of elbows
  5. Armpits

Treatment

  1. Keep skin cool and dry

Cool down

Dry off

Reduce friction

  1. Treat fever
65
Q

SKIN TAGS

  1. What is it?
  2. Appear most often where?
  3. Treatment? 2
A
  1. A skin tag is a small flap of flesh-colored or slightly darker tissue that hangs off the skin by a connecting stalk
  2. Appear most often in women and the elderly.

Usually benign

  1. Treatment

They can be easily removed by cutting or cryotherapy

66
Q

What are the following pictures showing?

A

Corn

Callus

67
Q

CORNS AND CALLOUSES

  1. Caused by?
  2. Leads to? 3
  3. Describe the difference b/w corns and calluses?
  4. What can they be confused with?
  5. Common cause?
A
  1. Caused by friction and pressure on the skin overlying bony prominences which…
  2. Leads to
    - hyperemia,
    - hypertrophy of dermal papillae, and
    - proliferation of keratin
  3. Corns often have a central hard core that is painful if lesion is pressed

Calluses do not contain a central core

  1. Corns and calluses can be confused with plantar warts
  2. Ill fitting shoes are the common cause
68
Q

Corns and Callouses

Prevention

A

Eliminate friction and pressure through

Shoes that fit correctly and distribute pressure evenly

Softer shoe materials

69
Q

Corns and Callouses treatment

3

A
  1. Paring down of hyperkeratotic lesions with a scalpel blade
  2. Keratolytic agents can be used intermittently (in this case, salicylic acid often used)
  3. Pumice stone