Section 3. Diaper Dermatitis and Rashes in the Diaper Area

Diaper dermatitis generally refers to the irritant contact dermatitis that may result from multiple factors in the area: macerated skin (softened by being wet), rubbing and wiping, and possibly the presence of ammonia in urine and proteases and lipases in stool, which cause skin irritation and breakdown. It can become complicated by secondary bacterial or yeast infections as well.

Insight

The so-called “Greek method” of washing the soiled diaper area under a running tap of warm water rather than using abrasive wipes is said to prevent diaper dermatitis.

Synonym Diaper rash, nappy rash.

Epidemiology

Age Most babies develop some form of diaper dermatitis during their diaper wearing years.

Gender M = F.

Prevalence At any one point in time, up to one-third of infants may have diaper dermatitis. The prevalence of severe diaper dermatitis (defined as erythema with ulcerations, oozing papules, and pustules) is 5%.

Etiology Excessive hydration of the skin and frictional injury leads to a compromised skin barrier and irritation from ammonia, feces, cleansing products, fragrances, and possible superinfection with Candida albicans or bacteria.

Season Reportedly highest during winter months, perhaps due to less frequent diaper changing.

Pathophysiology

The warm moist environment inside the diaper and frictional damage decreases the protective barrier function of the skin in the diaper area. Then predisposing factors such as seborrhea, atopic dermatitis, and systemic disease, as well as activating factors such as allergens (in detergents, rubbers, and plastic), primary irritants (ammonia from urine and feces), and infection (by yeast or bacteria) lead to a rash in the diaper area.

Physical Examination

Skin Findings

Type of Lesion Ranges from macular erythema (Fig. 3-1) to papules, plaques, vesicles, erosions, and rarely ulcerated nodules.

Color Ranges from mild erythema to diffuse beefy redness.

Palpation Ranges from nonindurated to prominently elevated lesions.

Distribution Diaper area, convex surfaces involved, folds spared. Severe cases may involve folds and have characteristic C. albicans satellite pustules.

Differential Diagnosis

Diagnosis The diagnosis of diaper dermatitis may be made clinically, although refractory response to conventional treatments should raise the suspicion of less common rashes in the diaper area.

Differential Diagnosis Diaper dermatitis must be differentiated from psoriasis, granuloma gluteale infantum (foreign body reaction, typically to baby powder, or topical steroids), primary candidiasis (perianal or intertriginous involvement with satellite lesions), seborrheic dermatitis, acrodermatitis enteropathica (AE; caused by zinc deficiency), and histiocytosis X.

Course and Prognosis