Dermatology in Family Medicine 1

1. Dermatology in Family Medicine 1 Clerkship Briefing Dr. Clayton Dyck

2. Dermatology in Family Medicine 1(Or, How To Suck Less in Derm) Clerkship Briefing Dr. Clayton Dyck

3. Objectives • 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

4. A call from Victoria Beach…

5. Dermatologic Diagnosis Approach is same as for any other medical condition: • History • Examination • Formulate differential diagnosis • Apply investigations to confirm/rule out

6. Dermatologic Diagnosis Use whatever algorithm you like: • TTIINNMAP • VITTAMIN DD • CITTIN VD

7. Tools Used in Dermatologic Assessment • Our ears • Our eyes • Our hands • Our noses (thankfully infrequently!) • Lab tests • Biopsies • Scrapings/clippings • Blood and urine samples

8. Questions to ask • Onset • Pattern • Skin symptoms • Systemic symptoms • Related factors • Environmental • Occupational • Other medical conditions • Drugs • Others affected? • To name a few…

9. An overview of terms…

10. macule

11. papule

12. plaque

13. nodule

14. pustule

15. vesicle

16. bulla

17. ulcer

18. wheal

19. purpura

20. excoriation

21. papulosquamous

22. Some Common Conditions

25. Herpes Zoster • VZV reactivation • Pain may precede rash • Usually dermatomal • Crusts usually fall off in 2-3 weeks • Worse in immunocomprimised, elderly

26. Herpes Zoster - Treatment • Wet dressings • Antivirals • May reduce post herpetic neuralgia • Within 48-72 hours of vesicle appearance • Eg famcyclovir 500 mg tid x 7 days

27. Ophthalmic Zoster - Treatment • Hutchinson’s sign • Refer to ophthalmologist urgently • 50% complications if antivirals not given

30. Tinea infections • Dermatophytes, candida • Topical antifungals • Keep dry! • If resistant/severe consider • Scraping • DM, immunocomprimised • PO antifungals

32. Onychomycosis • Trichophyton sp., Candida • Do KOH prep, culture first • Topical treatment only in simple cases • Usually needs oral treatment • Eg Lamisil 250 mg od x 12 weeks • Watch for toxicity

34. Dyshydrotic Eczema • Common if hands frequently moist/wet • Consider other irritants, allergens, fungi • Watch for superinfection • Treatment: • Moisturize x 3 • Topical steroids (usually moderate to high potency) • Topical immune modulators

37. Psoriasis • Peaks in 20s and 50s • Multifactorial • Exacerbated by trauma, infections, drugs, winter • 5-8% have psoriatic arthritis

38. Psoriasis - Treatment • Topical tar (ick!) • High - ultrahigh potency steroids • Vitamin D analogues • Phototherapy • Immunosuppressive agents

39. Topical Therapy • Choice of vehicle important: • Powder • Paste • Solutions (water or alcohol based) • Gels • Lotions • Creams • Ointments

40. Topical Therapy • Usually only a thin layer needed • 1 gram = 10 cm x 10 cm area • OD to BID usually sufficient

42. Topical Steroids • 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

43. Topical Steroids - Examples (by potency) Low Hydrocortisone 1 % Medium Betamethasone 0.1% High Mometasone Ultrahigh Augmented betamethasone

44. Topical Steroids - Adverse Fx • Irritation • Hypopigmentation • Skin breakdown • Rebound phenomenon • Atrophy • Striae • Systemic adsorbsion • And many more!

45. Nevus

46. Superficial spreading melanoma

47. Basal cell carcinoma

48. Cherry hemangioma

49. Actinic keratosis

50. When to biopsy • Change in: • Colour • Size (<6 mm) • Shape • Especially if weeks to months, rather than months to years • Bleeding • Any doubt