0071643192.pdf

DERMATOLOGY

CONTACT DERMATITIS

Contact dermatitis is an inflammatory reaction of the skin to a chemical,

physical, or biological agent. Clothing, jewelry, soaps, plants (including poi-

son ivy/oak), and topical medications (such as neomycin) are all causes. See

papules, vesicles, or bullae on an erythematous base, often in a linear configu-

ration. Treat by avoiding cause and with topical or oral steroids.

Plant Contact Dermatitis

SYMPTOMS/EXAM

■ Itching, burning, redness, and vesiculobullous formations occur 7–12 days after

first exposure. Often distribution is linear due to branch or leaf rubbing along

skin. Reactions may occur in <12 hours in individuals with prior exposure.

ETIOLOGY

■ Poison ivy (Toxicodendron radicans), poison oak, and poison sumac are the

most common causes. Other species in the Anacardiaceae family (includ-

ing mango tree, cashew nut tree) may also cause dermatitis.

■ The oil urushiol, common to all these plants, induces an allergic response

in approximately 70% of the population.

TREATMENT

■ Wash all contaminated skin and clothing with soap and water.

■ Antipruritic and topical therapies (oatmeal baths, ultrapotent topical

steroids, sedating antihistamines at night) are indicated. Oral steroids may

be necessary in patients with severe reactions. Taper over 1–2 weeks.

DIAPER RASH

SYMPTOMS/EXAM

■ Candidal diaper dermatitis is characterized by moist red patches with well-

demarcated borders and satellite papules or pustules. Usually involves

inguinal folds. Occurs in moist occluded areas exacerbated by heat, mois-

ture, friction, and the presence of urine or feces.

■ Diaper rash may also be due to irritant- or allergic-contact dermatitis.

These prefer the convexities (buttocks, thigh, abdomen, and perianal area)

and spare the inguinal creases. However, discriminating between these

causes may be difficult.

TREATMENT

■ Regular cleaning of skin and air exposure will treat most cases.

■ Consider Burrows solution for exudative lesions, topical anticandidal

agents such as nystatin with overlying zinc oxide paste for candidal infec-

tions, and topical corticosteroids for irritant/contact dermatitis.

PRESSURE ULCERS (DECUBITUS ULCERS)

Pressure ulcers cause significant morbidity in the elderly and the bed bound,

eg, obese, neurological impairment, postoperative patients particularly in nursing

homes and in the ICU.

Rashes with discrete

distributions (wrist, ears, neck,

belly button, fingers) suggest

contact dermatitis.