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Melanocytic Nevi (Moles)

  • Benign growths composed of nests of melanocytes.

  • More common in light/fair skin.

  • First appear in childhood as flat brown macules, evolve during adulthood into dome-shaped and fleshy papules or nodules with loss of pigmentation.

  • Divided into various subtypes: Acquired melanocytic nevi, Spitz nevi, blue nevi.

  • Many nevi regress in late adulthood.

  • Need monitoring, biopsy if melanoma suspected.

Congenital Nevi

  • Present at birth or become apparent during infancy.

  • Often larger than typical melanocytic nevi and have associated hair.

  • Need monitoring, biopsy if changing or if melanoma suspected.

  • Small = <1.5 cm; medium = 1.5 cm — 19.9 cm; large = >20 cm.

  • Giant congenital nevi associated with increased melanoma risk.

Dysplastic Nevi (Atypical Nevi, Clark’s Nevi)

Nevi with irregular outline, variable pigmentation, indistinct borders, and often >6 mm.

Multiple dysplastic nevi herald an increased risk for developing melanoma.

Need careful monitoring, biopsy if change in size/color.

Ephelides (Freckles)

Small brown macules on sun- exposed skin; more common in fair- complexioned.

Darken in response to the sun and fade with UV abstinence.

No risk of melanoma if diagnosis certain.

Lentigines (Solar Lentigines, Simple Lentig- ines, “Liver Spots”)

  • Occur in response to sunlight and persist even in absence of sunlight.

  • Vary in color from tan to dark brown, and can be up to 1 cm in diameter.

  • Location: Dorsal hands and face.

Spitz Nevus

  • Smooth-surfaced, firm, round, brown to pink-red papule usually developing in childhood. Often on face.

  • Benign, but histologically can be confused with melanoma.

DDx: Melanoma, pigmented BCC, SK.


Surgical excision if malignancy suspected.


Etiology: Dermatophyte infection of nail plate, often associated with tinea pedis. Less commonly due to yeasts and nondermatophyte molds.

History: Change in nail color and more brittle; usually asymptomatic.

Physical: Yellow discoloration, thickening, nail dystrophy, subungual hyperkeratosis, onycholysis. Toenails > fingernails.

Patterns include the distal subungual form (most common), the proximal white subungual form (may be a sign of HIV disease), and the white superficial form.

Investigations: 20% KOH direct microscopy, nail clipping/scraping for culture.

DDx: Nail psoriasis or trauma, eczema, lichen planus.


  • Topical antifungals much less effective. Ciclopirox (Penlac®) nail lacquer may be tried if po Tx not an option.

  • Important to culture fungus prior to initiating oral Tx

  • Terbinafine (Lamisil) 250 mg po qd × 6 wk for fingernails, × 12 wk for toenails; itraconazole (Sporanox) 200 mg po bid × 7 d, then 3 wk off—2 pulses for fingernails, 3 pulses for toenails.

  • Other less common options: Griseofulvin (esp. in kids), fluconazole.

  • Hepatotoxicity and ...

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