1. Skin lesion: shape
-Annular macules: drug eruptions, secondary syphilis, lupus.
2. Non Melanoma skin cancer
-Risk factors: >80% lifetime sun exposure before age 18 (single greatest risk factor). Other risk factors: (other than fair skin) smoking, psoralen/PUVA, coal-tar product use, M>>>F, chronic ulcers, burn scars, chronic draining sinus tracts. HPV.
3. Melanoma
-Nevi>6mm have increased risk of malignancy
-Cumulative sun exposure not a risk, or much less of a risk, compared to intermittent, intense sun exposure during childhood and adolescence-- i.e.blistering sunburns
-Other risk factors (in addition to fair skin): radiation exposure, immunosuppression, family history, familial atypical mole melanoma syndrome (FAMMS), lots of benign nevi, giant pigmented congenital nevi,
-1% of all skin cancers, 60% of all skin cancer deaths.
-Not always pigmented-- be wary of lesions that are slowly growing in size or bleed easily.
-In women, more than half of melanoma occur on legs.
4. Online tutorial of skin examination technique and findings:
http://www.logicalimages.com/educationalTools/learnDerm.htm
5. Squamous cell carcinoma
-Scaly and erythematous + raised base (vs actinic keratosis, no raised base)
-patch, plaque, or nodule, +/- scaling and/or an ulcerated center.
-Irregular borders, bleed easily
-Fleshy, heaped up edges (vs BCC: clear, heaped up edges)
-20% of all cases of skin cancer.
-Occurs on sun exposed areas, like extremities and face.
6. Basal cell carcinoma
-plaque-like or nodular. Waxy and translucent +/- ulcers or telangiectasia
-no associated itching or change in skin color.
-common on exposed skin surfaces but may occur anywhere.
-60% of primary skin cancers
-slow-growing lesions that invade local tissues but rarely metastasize.
7. Steroid vehicles & application:
-Cream: oil + water, drying effect with long-term use, good for acute inflammation.
-Ointment: oil-only base (i.e. petroleum jelly) with little water, excellent penetration (thus greater potency), good for dry skin
-Lotion: oil + water + alcohol, drying. Good for scalp, where it absorbs quickly without residue
-Gel: good for exudative lesions
-Apply 1-2 times a day. More frequent application does not lead to better results.
8. Steroid potency & side effects: (chart here)
-Psoriasis, lichen planus, hand eczema, alopecia need stronger steroids
-Atopic dermatitis, eczema, stasis dermatitis, seborrheic dermatitis need medium steroids
-Dermatitis on face, eyelids, diaper area - use weaker steroids.
-Side effects: skin atrophy (most common), hypopigmentation (more obvious in darker skinned people); however superpotent topical steroids can have the side effects of systemic steroids- HPA axis suppression, avascular necrosis of femoral head, HTN, hyperglycemia, glaucoma.
9. Tinea capitis: 
-Treat with systemic antifungals, as topical is unable to penetrate hair shaft.
-Griseofulvin is the only approved drug in the US
-20-25 mg/kg/day for 6-12 weeks using microsize formation
-10-15 mg/kg/day if ultramicrosize formation, as it is more easily absorbed.
10. Tinea unguium (onychomycosis):
-Treat with systemic antifungas, as topical cannot get into nail.
-Don't use griseofulvin, as it has low affinity for keratin and will take forever to work
-Treat with terbinafine 250 mg/day for 12 weeks (toenails) or 6 weeks (fingernails)
-Alternative: itraconazole pulses, 200mg BID, one week on, 3 weeks off. Fingernails need 2 rounds, toenails 3 rounds.