Dermatology in Family Medicine 1
Clerkship Briefing
Dr. Clayton Dyck
Dermatology in Family Medicine 1
(Or, How To Suck Less in Derm)
Clerkship Briefing
Dr. Clayton Dyck
Objectives
1.
2.
3.
4.
Use appropriate terminology to describe
common skin presentations seen in family
medicine
Apply a systematic approach to their
diagnosis
Know the modalities used in their treatment
Understand basic principles of topical
therapy
A call from Victoria Beach…
Dermatologic Diagnosis
Approach is same as for any other
medical condition:
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History
Examination
Formulate differential diagnosis
Apply investigations to confirm/rule out
Dermatologic Diagnosis
Use whatever algorithm you like:
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TTIINNMAP
VITTAMIN DD
CITTIN VD
Tools Used in Dermatologic
Assessment
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Our ears
Our eyes
Our hands
Our noses (thankfully infrequently!)
Lab tests
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Biopsies
Scrapings/clippings
Blood and urine samples
Questions to ask
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Onset
Pattern
Skin symptoms
Systemic symptoms
Related factors
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Environmental
Occupational
Other medical conditions
Drugs
Others affected?
To name a few…
An overview of terms…
macule
papule
plaque
nodule
pustule
vesicle
bulla
ulcer
wheal
purpura
excoriation
papulosquamous
Some Common Conditions
Herpes Zoster
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VZV reactivation
Pain may precede rash
Usually dermatomal
Crusts usually fall off in 2-3 weeks
Worse in immunocomprimised, elderly
Herpes Zoster - Treatment
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Wet dressings
Antivirals
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May reduce post herpetic neuralgia
Within 48-72 hours of vesicle appearance
Eg famcyclovir 500 mg tid x 7 days
Ophthalmic Zoster Treatment
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Hutchinson’s sign
Refer to ophthalmologist urgently
50% complications if antivirals not given
Tinea infections
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Dermatophytes, candida
Topical antifungals
Keep dry!
If resistant/severe consider
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Scraping
DM, immunocomprimised
PO antifungals
Onychomycosis
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Trichophyton sp., Candida
Do KOH prep, culture first
Topical treatment only in simple cases
Usually needs oral treatment
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Eg Lamisil 250 mg od x 12 weeks
Watch for toxicity
Dyshydrotic Eczema
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Common if hands frequently moist/wet
Consider other irritants, allergens, fungi
Watch for superinfection
Treatment:
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Moisturize x 3
Topical steroids (usually moderate to high
potency)
Topical immune modulators
Psoriasis
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Peaks in 20s and 50s
Multifactorial
Exacerbated by trauma, infections,
drugs, winter
5-8% have psoriatic arthritis
Psoriasis - Treatment
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Topical tar (ick!)
High - ultrahigh potency steroids
Vitamin D analogues
Phototherapy
Immunosuppressive agents
Topical Therapy
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Choice of vehicle important:
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Powder
Paste
Solutions (water or alcohol based)
Gels
Lotions
Creams
Ointments
Topical Therapy
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Usually only a thin layer needed
1 gram = 10 cm x 10 cm area
OD to BID usually sufficient
Topical Steroids
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Consider thickness of skin, thickness of
lesion, moistness of area
Choose one drug of each potency
Consider occlusion with lower potency
steroids
Avoid extended periods of treatment
Topical Steroids - Examples
(by potency)
Low
Hydrocortisone 1 %
Medium
Betamethasone 0.1%
High
Mometasone
Ultrahigh
Augmented
betamethasone
Topical Steroids - Adverse Fx
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Irritation
Hypopigmentation
Skin breakdown
Rebound phenomenon
Atrophy
Striae
Systemic adsorbsion
And many more!
Nevus
Superficial spreading melanoma
Basal cell carcinoma
Cherry hemangioma
Actinic keratosis
When to biopsy
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Change in:
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Colour
Size (<6 mm)
Shape
Especially if weeks to months, rather than months
to years
Bleeding
Any doubt
Impetigo
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S. aureus, S. pyogenes, or both
Common in schools, daycares
Treatment
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Bactroban tid x 10 days
Cloxacillin 250 qid x 5-10 days
Keflex 250 qid x 5-10 days
Resistance common, may need swab
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Consider Bactroban in nares bid x 5 days
Fifth’s Disease
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Parvovirus B19
Peaks in school age children
Mild flu-like symptoms
Arthritis in 10%
Teratogenic, especially before 20 weeks
Erysipelas
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Group A Streptococci
Sudden onset, can be painful
Fever, sick
Penicillin V po/iv for 2 weeks
Macrolide if penicillin allergic
Hand Foot and Mouth Disease
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Coxsackie A16 virus
Mild flu Sx, fever
Usually children < 5 years
Self limited, resolve within 10 days
Scabies
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Itchy - worse at night
Usually more than one family member
A great mimic - consider if:
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Impetigo
Eczema
Idonomata
Scabies - Treatment
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Treat family concurrently
Wash all clothes/bedding/towels
Permethrin cream
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Everywhere but hair, mouth, eyes
Rinse after 12 hours
Infants - precipitated sulfur
Consider 2nd treatment
Itchiness persists days to weeks later
Some short snappers
Pityriasis rosea
paronychia
Molluscum contagiosum
rosacea
Stasis dermatitis
wart
Subungual hematoma
Take home “berries”
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Know your terminology
When in doubt - back to first principles
Always keep a differential diagnosis
Use the right topical for the job
Don’t be afraid to overbiopsy
Objectives
1.
2.
3.
4.
Describe common skin presentations
seen in family medicine
Apply a systematic approach to their
diagnosis
Know the modalities used in their
treatment
Understand basic principles of topical
therapy
References
Skin Diseases: Diagnosis and Treatment, T P
Habif et al, Elsevier 2005
Color Atlas and Synopsis of Clinical
Dermatology, T B Fitzpatrick, McGraw-Hill,
1997
Images.MD (NJM Library Database)
http://missinglink.ucsf.edu/lm/DermotologyGloss
ary
Questions?
Or itching to leave?