Lecture 17: Dermatology II Flashcards
(88 cards)
1
Q
Acne
A
● Inflammatory skin disease affecting pilosebaceous glands ● Common on the face, back, chest, shoulders/arms, neck ● Most prevalent during adolescence ● Often correlates with onset of puberty ● Affects 85% of 15-24 year-olds ● Impacts quality of life ● Physical scarring ● Emotional impact
2
Q
Acne – Pathophysiology
A
1. Hormonal (androgenic) trigger ▪Associated with puberty; genetic risk 2. Sebum production 3. Altered keratinization/ Plugged duct 4. Propionibacterium acnes (P. acnes) follicular colonization ▪Break down sebum → irritating free fatty acids 5. Release of inflammatory mediators 6. Local tissue injury 7. Comedones → papules/pustules → nodules
3
Q
Acne Pathophysiology
A
● Pilosebaceous unit in the dermis
○ Hair follicle + sebaceous gland
○ Connected to skin surface by duct lined with epithelial cells
■ Hair shaft passes through
4
Q
Sebaceous gland produces
A
sebum
It:
● Protects skin from light and retain moisture
● Antibacterial properties, pro- and anti-inflammatory
● Involved in wound healing
5
Q
Acne – Clinical Presentation
A
Open or close comedones
Nodules
Pustules
Papules
6
Q
Open comedone
A
raised open follicle → black surface pigmentation (“black head”)
7
Q
Closed comedone
A
raised blocked follicle (“white head”)
8
Q
Nodule
A
disruption of follicular wall and release of
contents to surrounding dermis
9
Q
Pustule:
A
papule with noticeable white or yellow centered
center (purulence)
10
Q
Papule
A
closed, swollen, erythematous
11
Q
Acne – Risk/Exacerbating Factors
A
● Chemicals ● Cosmetics ● Diet (breads, starches, sugar) ● Excoriation (picking, squeezing) ● Hormones (pregnancy, puberty) ● Hydration (humidity, sweating) ● Mechanical (hats, headbands, helmets) ● Medications ● Occupational ● Stress
12
Q
Acne – Grading/Classification
A
Severity defined by the number and type of acne lesions
●Not standardized
13
Q
Mild acne
A
Few erythematous papules and occasional pustules mixed with comedones
14
Q
Moderate acne
A
Many erythematous papules and pustules and prominent scarring
15
Q
Severe acne
A
Extensive pustules, erythematous papules, and multiple nodules in an inflamed background
16
Q
Acne – Self-Treatment Pearls
A
Self-treatment is appropriate for mild acne only
• Address exacerbating factors – can be done before or in conjunction with treatment
• Treatment needs to be chronic, continuous, consistent -> adherence is important
• Set realistic goals: Symptoms likely to improve, but may not
resolve
17
Q
Acne – Exclusions to Self-Care
A
Moderate to severe acne
● Pregnancy
● Suspected rosacea
18
Q
Rosacea
A
- common skin condition that causes blushing or flushing and visible blood vessels in your face
- It may also produce small, pus-filled bumps
- These signs and symptoms may flare up for weeks to months and then go away for a while
19
Q
Acne – Non-Pharmacologic Therapy
A
● Avoid abrasive scrubs/brushes ○ May worsen acne ● Cleanse skin twice daily ○ Mild soap or cleanser ● Dietary changes? ● Hydration ● Limit/eliminate exacerbating factors ● Physical therapies – glue-based strips, light therapy ○ Evidence? ○ Considered adjunct to pharmacologic therapy
20
Q
Acne – Pharmacologic Therapy
A
Topical therapy is the standard of care ● Several OTC options • Adapalene • Benzoyl peroxide • Hydroxy acids (AHA, BHA) • Sulfur +/- resorcinol
21
Q
Adapalene Brand Name
A
Differin
22
Q
Adapalene MOA
A
- Anti-inflammatory; comedolytic; keratolytic
- Affects lesions not yet visible on the skin.
23
Q
Adapalene OTC
A
0.1% gel
24
Q
Adapalene Dosing
A
Apply daily at bedtime.
25
Adapalene Adverse Effects
allergic dermatitis; dry skin*; skin irritation*
| *Tend to improve after the first month of therapy
26
Adapalene Patient Education
Avoid prolonged sun exposure/use sunscreen.
| Full therapeutic effect takes 8-12 weeks.
27
Benzoyl Peroxide Brand Name
Acne Medication®; AcneFree®; BPO®; PanOxyl®; etc
28
Benzoyl Peroxide MOA
Antibacterial; comedolytic; keratolytic
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Benzoyl Peroxide OTC Products
2.5-10% (higher strengths available as Rx)
| Creams, gels, washes
30
Benzoyl Peroxide Dosing
Initiate 2.5% with 1-2 applications daily.
Increase frequency/strength every 1-2 weeks.
May increase until a mild peeling occurs.
31
Benzoyl Peroxide Adverse effects
Allergic contact dermatitis/anaphylaxis; bleaching; photosensitivity;
skin irritation*
*Tend to improve after the first month of therapy
32
Benzoyl Peroxide Patient Education
Avoid contact with clothes or hair – product has bleaching effects.
Avoid prolonged sun exposure/use sunscreen.
Full therapeutic effect takes 4-6 weeks.
33
Hydroxy Acids - AHAs Types
Alpha hydroxy acids (AHAs): citric, glycolic, and lactic acids
34
Hydroxy Acids - AHAs MOA
Keratolytic (assist in skin turnover/exfoliation)
35
Hydroxy Acids - AHAs OTC Products
4-10% (higher strengths available through dermatologists)
36
Hydroxy Acids - AHAs Adverse Effects
irritation; stinging
37
Hydroxy Acids - BHAs Types
Beta hydroxy acids (BHAs): salicylic acid
38
Hydroxy Acids - BHAs MOA
Comedolytic; keratolytic
39
Hydroxy Acids - BHAs OTC Products
0.5-2% (higher strengths available as Rx)
| Gels, washes
40
Hydroxy Acids - BHAs Dosing
Gel: 1-2 times per day to affected area
Wash: 1-3 times per day
May increase until a mild peeling occurs
41
Hydroxy Acids - BHAs Adverse effects
Dryness; peeling
Toxicity: dizziness; hyperpnea; loss of hearing; nausea; tinnitus;
vomiting
42
Hydroxy Acids - BHAs Patient Education
Avoid excessive use.
Drug interactions – anticoagulants, NSAIDs, etc.
Full therapeutic effect takes 4-6 weeks.
Limit use to affected area.
43
Sulfur ± Resorcinol
Sulfur: precipitated or colloidal
Resorcinol: enhances effect of sulfur; not effective as monotherapy
44
Sulfur ± Resorcinol MOA
Antibacterial; keratolytic
45
Sulfur ± Resorcinol OTC Products
3-8% ± 2-3%
| Creams, gels, lotions
46
Sulfur ± Resorcinol Dosing
1-3 times per day
47
Sulfur ± Resorcinol Adverse effects
Chalky yellow color; unpleasant odor
| Avoid with allergy to sulfa drugs
48
Sulfur ± Resorcinol Patient Education
Not generally recommended for long-term use.
49
Creams/lotions as acne formulations
Less irritating/less effective – sensitive skin
50
Gels as acne formulations
Longest contact time – generally most effective
| • Drying effects
51
Ointments as acne formulations
Occlusive – not used, worsen acne
52
Soaps/cleansers as acne formulations
Short contact time – little value
53
Acne – Product Selection
Product selection is based on individual patient needs,
skin type and acne severity
● “start low go slow”
54
Acne Product efficacy
Adapalene and benzoyl peroxide have similar efficacy
• Benzoyl peroxide: efficacy low concentration = efficacy high concentration
• Salicylic acid: less effective than benzoyl peroxide or adapalene
• Sulfur: adjunct therapy
55
Acne Patient education
Avoid eyes, mouth, open skin (cuts/scrapes).
| • Do not combine with other products (unless instructed)
56
Improvement of acne
Complete resolution is unlikely
○ Decrease in number and severity of lesions is realistic
○ No improvement in 6 weeks → REFER
57
Continuation
Once symptoms have improved, continue treatment for
prevention
○ May decrease dose/frequency as tolerated
58
UVC Rays
- are short and don't penetrate the ozone layer
59
UVB rays
- are longer and reach the skin, causing burning, tanning and signs of aging
60
UVA rays
- are the longest, they penetrate deep into the skin and cause the release of free radicals, as well as DNA changes that can result in skin cancer
61
Ultraviolet Radiation
Includes UVA and UVB rays
• Clouds only filter out 10-30%
• White or light colored surfaces reflect UVR
• Water reflects no more than 5% UVR (so you can burn
while under water…)
• Is cumulative
62
UVA
Majority of UVR
• Penetrates more deeply than UVB (dermis vs. epidermis)
• Less potent than UVB
• Immune system suppression and DNA damage
• Contributes to photoaging and skin cancer
• Primarily responsible for drug-induced photosensitivity
reactions
• Can penetrate window glass
63
UVB
```
1000x more potent than UVA
• Highest intensity from 10am to 4pm
• Primary cause of skin cancer
• Needed for vitamin D production
• Increases with increasing altitude
• Does not penetrate window glass
```
64
Suntan/Sunburn
```
Degree depends on
• Type and amount of radiation
• Thickness of skin layers
• Skin pigmentation
• Skin hydration
• Distribution and concentration of peripheral blood vessels
```
65
Suntan MOA
UVR → stimulates melanocytes → melanin generation and
| oxidation
66
Suntan Clinical presentation
Immediate/prolonged darkening of the skin
| -Does not offer “protection
67
Sunburn MOA
UVR → DNA damage → injury → inflammation + RBC leak
68
Sunburn Clinical Presentation
```
Superficial (partial-thickness) burn
• Mild erythema, tenderness, pain, edema
• Severe (full-thickness) burn
• Development of vesicles
• Fever, chills, shock
```
69
Sunburn Management
Symptomatic/supportive care
• Skin protectants – cocoa butter, petrolatum, aloe
• Systemic analgesics
• Topical anesthetics – benzocaine, dibucaine, lidocaine, tetracaine
70
Photoaging
Characterized by a breakdown of
| elastin
71
Photoaging Risk Factors
```
Chemical exposure
• Clinical and histologic changes
• Smoking
• UVR exposure
• Wind exposure
```
72
Photoaging Clincal Presentation
```
May present as changes in skin color,
surface texture, and functional
capacity
• May include development of pre and
cancerous lesions
```
73
Skin Cancer
- Non-melanoma skin cancers (NMSCs)
| - Melanoma
74
Non-melanoma skin cancers (NMSCs)
Basal cell carcinoma
| • Squamous cell carcinoma
75
Melanoma
Arises from normal skin or mole
76
Skin Cancer – Melanoma Assessment
ABCDE rule for the ealry detection of melanoma
A- asymmetry
B- Borders ( the outer edges)
C- Color ( dark black or have multiple colors)
D- greater than 6 mm)
E- Evolving ( change in size, shape and color)
77
Sunburn & Photoaging Risk Factors
```
Fair skin
• Blonde or red hair
• Blue, green, or gray eyes
• History of freckling
• History of ≥1 serious/blistering sunburn(s)
• Family history of melanoma
• Immunosuppressant use
• History of autoimmune disease
• Excessive lifetime UVR exposure
```
78
Exclusions to Self-Care
● Allergy to all sun protectant ingredients
| ● <6 month of age
79
Non-Pharmacologic Treatments
```
Avoidance
■ Avoid tanning equipment
■ Minimize exposure during peak hours
■ Seek shade
○ Protective clothing
■ Hat
■ Long sleeves
■ SPF clothing
```
80
Pharmacologic Treatments
Sunscreen
81
Prevention – Sunscreen Properties
“Broad spectrum”
82
Sun protection factor (SPF)
■ Increased SPF = increased protection
● SPF 15 blocks 93% UVB filtered
● SPF 30 blocks 96.7% UVB filtered
● MAX = SPF 50+
83
Water-resistant
■ Cream-based > alcohol-based
| ■ Duration listed on label
84
Prevention – Sunscreen Types Chemical
Absorb UVR
● Products combined to maximize
UVA/UVB absorption
85
Prevention: Sunscreen Types Chemical Examples
```
● Aminobenzoic acid and derivatives
● Anthranilates
● Benzophenones
● Cinnamates
● Dibenzoylmethane derivatives
● Salicylates
```
86
Prevention: Sunscreen Types Physical
Reflect/scatter UVR
87
Prevention: Sunscreen Types Physical Examples
Titanium dioxide
| ● Zinc oxide
88
Prevention – Sunscreen Application
Apply 15-30 minutes before exposure
• Reapply every 2 hours, or after 40-60 minutes of swimming or
sweating or after toweling off
• For sufficient protection, the average adult in a bathing suit should
apply 9 portions of sunscreen (approximately ½ teaspoon each)
• Face/neck = ½ teaspoon
• Arms/shoulder = ½ teaspoon per side
• Torso = ½ teaspoon front/back
• Legs/feet = 1 teaspoon per side
