Dermatology for the podiatrist

1. 4/23/10 Justin Endo, M.D. Dermatology for the podiatrist

2. Disclosure • No financial disclosures • Primary reference and images unless otherwise specified from Bolognia et al.

3. Objectives • Diagnose dermatologic conditions affecting the lower leg • Discuss management options • Understand the limitations of biopsies, especially shave biopsies, using standard breadloaf histologic grossing methods • Describe a lesion and consult dermatology appropriately

5. Vasculitis • Immune-mediated destruction of vessels • Often classified by vessel size involved • Small: • Sometimes renal involvement • Palpable purpura • Medium/large: • +/- systemic symptoms • Ulcers • Livedoreticularis • Nodules

6. Vasculitis • Dermatology and/or rheumatology consult to help rule out systemic involvement • If systemic involvement (or severely symptomatic small vessel disease without renal involvement) • Steroids or other immunosuppressants • Compression stockings for small vessel vasculitis

8. Pigmented purpuricdermatosis • Capillaritis • Various morphologies • Annular telangiectasias (Majocchi) • Cayenne pepper petechiae and macules (Schaumberg) • Eczematoid patches (Ducas and Kapetanakis) • Lichenoid patches (Gougerot and Blum) • Treatment • Observation • Topical steroids rarely helpful

9. Pyodermagangrenosum (PG) • Clinical features • Pathergy (sterile pustule at sites of trauma) • Wound or ulcer that keeps getting “infected” despite debridement • Undermining and rolled borders • Cribiform healing • Erythematous margins • Bullous and granulomatous variants

10. PG • Associated conditions • Inflammatory bowel disease • Hematologic malignancy (bullous variants) • Paraproteinemia • Up to 50% idiopathic • Diagnosis of exclusion • Infectious etiology workup needed • Biopsy will not RULE IN diagnosis but RULES OUT other causes of chronic ulcer

11. PG • Treatment • NO DEBRIDEMENT!!! • NO DEBRIDEMENT!!! • NO DEBRIDEMENT!!! • Dermatology consult • Steroids (often systemic) • Immunosuppressives

12. Premalignant & malignant • Kaposi’s sarcoma • Squamous cell carcinoma • Melanoma • Basal cell carcinoma • Cutaneous lymphoma

14. Kaposi’s sarcoma • Abnormal endothelial neoplasm caused by human herpes virus 8 (HHV-8) • Pink, black-violet nodules, plaques, or polyps • 4 variants • Chronic/classic (Mediterranean) • African endemic • Iatrogenically immunocompromised (CyA) • AIDS related

15. Kaposi’s sarcoma • Childhood lymphadenopathic variant is fulminant and fatal • Chemotherapy +/- XRT usually before surgery due to multifocality

17. Squamous cell carcinoma • Malignant infiltration of keratinocytes • Risk factors: • Immunosuppression (transplant) • Sun damage • Can follow nerves, invade into bone, and metastasize • Refer to dermatology to discuss treatment options, regardless of biopsy “margins”

18. Answers.com

20. Melanoma, acrallentiginous • Rarer type of melanoma • Significant proportion of melanoma type in Asian and African skin • Brown to black macule with irregular borders, color variegation, longitudinal melanonychia • Consider biopsy • Fair-skinned individuals • Width >=3mm • Changing lesion

21. Melanoma, acrallentiginous • Staging / prognosis depends upon • HistologicBreslow depth • Lymph node involvement • Mitotic rate • Ulceration • Treatment • Wide local excision • Sentinel lymph node biopsy for melanomas > 1 mm • Adjuvant treatments and clinical trials

22. dermoscopic.blogspot.com/

23. Basal cell carcinoma • Most common skin cancer • Least likely to metastasize • Recommend referral to dermatology, regardless of biopsy “margins” • Surgical management depends upon histologic appearance

24. An Bras Dermatol 2005

25. Primary cutaneous lymphoma • Abnormal, clonal T or B cell proliferation • Violaceous nodules (B cell) or widespread eczematous-like plaques (T cell) • Differential includes “pseudolymphoma” benign lymphocytic hyperplasia • Referral to dermatology and hematology/oncology for treatment options

26. Benign neoplasms • Dermatofibroma • Disseminated superficial actinic porokeratosis • Kyrle’s disease • Poroma

28. Dermatofibroma • Pink to brown dome shaped papules (sometimes flatter) that dimples when squeezed • Thought to be reactive to trauma • Management options • Expectant (watchful neglect) • Punch / excise • Triamcinolone injection • Cordran tape

30. Disseminated superficial actinic porokeratosis (DSAP) • Multiple flesh colored, scaly papules or plaques with double edge rim of scale • Malignant transformation risk is low • Treatment is generally unsatisfactory • Expectant (watchful neglect) • Cryotherapy • Topical 5-FU or imiquimod • Topical retinoids • Curettage

31. VGDR.com

32. Kyrle’s disease • Keratin perforates through skin • ? form of prurigo nodularis associated with renal disease • Treatment (difficult) • Topical steroids • Antipruritic lotions • UV light • Laser

33. Emedicine.com

34. Poroma • Benign tumor of eccrine > apocrine duct origin • Palmo-plantar vascular papules, nodules, plaques • No treatment indicated (or excise if symptomatic)

35. Scaly eruptions • Lichen planus • Psoriasis

37. Lichen planus • Purple polygonal papules and plaques, sometimes with lacy netlike Wicham’sstriae • Affects wrists, arms, genitals, buttocks, oral mucosa • Association with hepatitis C, metal contact allergies, hepatitis B vaccine, medications • Can be difficult to treat • Topical steroids • Light • Antimalarials (hydroxychloroquine)

39. Photos AAFP.org Psoriasis • Polygenetic disorder • Itchy, red, well-demarcated plaques with silvery scale involving the scalp, torso, umbilicus, gluteal fold, extensor extremities • Often nail pitting and oil spots • Sometimes involving genitals, axillae • Rarely palmar or plantar distribution • Uncommonly pustular or erythrodermic Oil spot Nail pit

40. Psoriasis • Triggers • Trauma • Infection (streptococcal, HIV) • Hypocalcemia • Drugs (lithium, interferon, beta blocker, systemic steroid, antimalarials) • Major comorbidity: metabolic syndrome!

41. Psoriatic arthritis • Enthesitis • Morning stiffness lasting at least 1 hour • 5-30% of all psoriasis patients • 15% of cases arthritis precedes skin lesions

42. Psoriatic arthritis • Categories • Classic (DIP) • Mono/asymmetric arthritis • RA-like (small and medium joints) • Arthritis mutilans • Spondyloarthritis

43. Psoriasis: Treatment • Depends upon extent/sites of skin disease, arthritis, comorbidities, lifestyle • Topical steroids and vitamin D analogs • Light • Methotrexate • Biologics (e.g., etanercept, infliximab, adalimumab, ustekinumab)

44. Metabolic • Necrobiosis lipoidica (diabeticorum) • Erythema nodosum • Pretibial myxedema

46. Necrobiosislipoidica • Yellow-red-brown plaques +/- atrophy or ulceration on shins • NOT strictly associated with diabetes or glucose control • Treatment • Potent topical or intralesional steroid into active borders • Niacinamide • Light • Surgery as last line

48. Necrolyticacralerythema • Associated with hepatitis C • Obtain hepatitis C antibody study and refer to hepatology

49. eMedicine.com

50. Erythemanodosum (EN) • Tender, red, poorly demarcated, subcutaneous deep-seated nodules on anterior shins resolving like a bruise • +/- arthralgias and fevers • Typically young adults • RARELY (if ever) ulcerates • Usually acute and self-limited eMedicine.com