Chapter 6: DERMATOLOGY

GENERAL DERMATOLOGY

CONTACT DERMATITIS, A DIAPER RASH

Contact dermatitis is a diaper rash that spares the inguinal folds. Treat with more frequent diaper changes and a topical barrier, such as zinc oxide.

(DOUBLE TAKE) CUTANEOUS CANDIDIASIS, A DIAPER DERMATITIS

Cutaneous candidiasis, a diaper dermatitis, can occur secondary to a contact dermatitis or recent antibiotic use. It presents as a beefy red rash with papular satellite lesions. This rash goes into the inguinal folds. Use a KOH prep to confirm diagnosis, and treat with a topical antifungal, such as nystatin or clotrimazole.

IMAGE (includes satellite lesions): www.pbrlinks.com/CUTASCAN1

(DOUBLE TAKE) ATOPIC DERMATITIS (ECZEMA)

In babies, atopic dermatitis (eczema) SPARES the diaper folds/flexural surfaces (but not in older kids). It is PRURITIC and LICHENIFIED. Food allergies CAN exacerbate eczema. The contribution of early food ingestion to the development of atopic dermatitis is controversial. Eggs, fish, milk, peanut, soy, wheat and strawberries are the foods thought to possibly contribute, but delaying their introduction doesn’t help. Positive skin and RAST tests for foods are not predictive, either. Treatment options include emollients and topical steroids. Avoid use of steroids in areas where the skin is thin. Use the lowest potency steroids that work. Non-steroidal treatment options include topical calcineurin inhibitors (tacrolimus and pimecrolimus) and topical PDE4 inhibitors (crisaborole). Watch for superinfection if the eczema is not improving with appropriate therapy.

IMAGE: www.pbrlinks.com/ECZEMA1

NUMMULAR ECZEMA

Nummular eczema refers to coin-shaped eczematous lesions usually on the extensor surfaces of extremities. Lesions are uniform, without any central clearing. Lesions may ooze, crust, or have a scaling pattern. Treat with steroids.

IMAGE: www.pbrlinks.com/NUMMULAR1

MNEMONIC: Imagine that you are standing with your arms in abduction, and you are balancing silver COINS that are UNIFORM in color (without central clearing) on the BACK of both of your arms (extensor surface).

(DOUBLE TAKE) ECZEMA HERPETICUM

Eczema herpeticum is a potentially life-threatening disseminated herpes (HSV) infection occurring at sites of skin damage, including sites of eczema. Look for HSV Vesicles + Crusted Lesions. Even if a description is not given of a vesicular rash, have a high index of suspicion for a rash “not improving with steroids and/or antibiotics.” Diagnose with HSV PCR or a viral culture, but do not delay treatment. A Tzanck smear can support the diagnosis. Treat by STOPPING topical steroids and/or immunosuppressants and starting Acyclovir.

IMAGE: www.pbrlinks.com/ECZEMAHERPE1
IMAGE: www.pbrlinks.com/ECZEMAHERPE2
IMAGE: www.pbrlinks.com/ECZEMAHERPE3