Phototoxicity Photoallergy Sunburn reaction, erythema, edema. Direct tissue injury Occurs after first exposure. Onset minutes to hours. Large dose of agent needed for eruption. Pruritic, eczematous lesions. Type IV delayed hypersensitivity. Does not occur after first exposure. Onset 24-48 hours. Small dose of agent.
Resin from plant called urushiol can oxidize and turn black on the skin which is called a “black lacquer spot”
Treatment Ultra potent topical steroids if a localized area such as clobetasol propionate 0.05% Systemic steroids often needed Medrol dose pack too little, and too short Prednisone 40-60mg with a slow taper over 12-18 days, maybe longer if reactivation
Ivy Block etc. may help prevent the oils from the plant getting to the skin by acting as a barrier which you apply as a lotion prior to potential contact Wash all clothes, tools, shoes, and gloves after contact since resin may last for years even when air dried.
Swimmer’ Itch Sea Bather’s Erupt. Water: fresh or salt Body part: uncovered Locale: North US and Canada Cause: cercarial forms of nonhuman schistosomes(snails) Water: salt Body part: covered Locale: Florida and Cuba Cause: larval forms of marine coelenterates (sea anemone, jellyfish)
Treatment/Prevention Swimmer’s itch: symptomatic Rx for itch. Vigorous towel drying may prevent penetration of the cercariae Sea Bather’s eruption: symptomatic Rx for itch. Remove swimwear before shower since fresh water may cause discharge of nematocysts. Heat dry swimwear
Treatment Perioral Dermatitis Avoid high potency topical steroids. If topical steroids have been used for longer than 1 month prior to diagnosis, may need to use a mild (1%) hydrocortisone cream to prevent rebound flare.
Treatment Perioral Dermatitis Oral antibiotics: Doxycycline, and minocycline good choices Topicals: Clindamycin lotion, metronidazole gel, lotion Elidel and Protopic have shown some promise
Perioral Dermatitis Remember : topical steroids are most often the cause, not the cure.
Be careful with betamethasone/clotrimazole combination Never more than 2 weeks The betamethasone component too potent for most fungal infections, and high risk of steroid atrophy Worsening tinea Striae
Live up to 48hrs off host Nursing homes, group homes etc. Scraping may be negative
If your patient has: Chronic itch Worse at night Others with itch in household No other obvious cause Be Suspicious of Scabies
Scabies Treatment 5% Permethrin cream (Elimite) neck to toes (occasionally face and scalp ) overnight. Repeat in 1 week Treat others in house No need for lindane Change bedding after each treatment Ivermectin 150-200 mcg/kg single dose. May repeat in 1 week
Dermatology “Doc, I Have This Rash…” Joseph S. Baler M.D. September 7, 2013