Defeating diaper dermatitis-Mission impossible

Most cases of diaper dermatitis are irritant diaper dermatitis, Dr. Paller notes. It's estimated, however, that 40 percent to 75 percent of cases of diaper dermatitis lasting three or more days are complicated by documented candidiasis, which occurs after the skin barrier has been broken down by common diaper dermatitis.

Study specifics

The efficacy and safety of Vusion was demonstrated in a double-blinded, vehicle-controlled and parallel group study, the results of which were published in Cutis in 2006.

That study found that among 330 patients, seven days of application of topical miconazole nitrate ointment produced an overall cure rate that was twofold greater than with zinc oxide and white petrolatum (23 percent vs. 10 percent), which was statistically significant. Moreover, the rate of complete rash clearance, measured as zero at a follow-up visit on day 14, was 38 percent for those who received the active comparator and 11 percent for those who got placebo, a finding that was statistically significant. Discontinuation was significantly less for those who received miconazole nitrate compared with placebo: 4 percent versus 47 percent. Adverse events reported in the study were determined to be either unlikely to be related or unrelated to the active medication.

"The combination of antifungal and zinc oxide paste simplifies treatment of diaper dermatitis and provides a substitute for putting on treatment for the candidal infection and then a barrier," Dr. Paller tells Dermatology Times. "Moms won't need to put on the antifungal agent, clean off their hands, and then put on zinc oxide paste. It's one application, so it makes it less messy and easier for moms."

She notes, however, that the greater expense of the combination product is the cost for this convenience.

Ascertaining etiologies

Dermatologists see few cases of diaper dermatitis, with the condition mainly being treated by pediatricians and primary care physicians, according to Dr. Paller.

"It's really recalcitrant cases that are seen by a pediatric dermatologist," Dr. Paller notes.

The challenge for the pediatrician is to evaluate if there is a secondary candidal infection in addition to the dermatitis. Other inflammatory conditions in the diaper area may be misdiagnosed as irritant or candidal diaper dermatitis. Among these are:

On clinical examination, irritant diaper dermatitis most commonly presents with redness on convex surfaces in opposition to the diaper, compared with more inguinal fold involvement in candidal infection. However, irritant dermatitis may also show discrete erythematous papules, and it is difficult to distinguish from candidal infection on clinical grounds alone. While a KOH test, or potassium hydroxide preparation, can determine if there is a secondary Candida albicans infection, a busy pediatrician may not have the time to perform the test nor have the knowledge of how to perform the test and evaluate the results.

"Performing a culture is not terribly useful because many infants are colonized by Candida albicans, and the culture may not detect active infection," Dr. Paller says. "Some primary care physicians will instruct the patient to apply topical nystatin, which may not be as effective as azole antifungals, but will not take the time to educate patients about handling irritant diaper dermatitis and the role of protective agents like zinc oxide paste."

Take-home message

The introduction and improvements in commercially available superabsorbent disposable diapers have decreased the overall incidence of diaper dermatitis and particularly of severe diaper dermatitis, Dr. Paller observes.

Still, parents can take several preventive steps to avoid the development or recurrence of diaper dermatitis. These tactics include frequent diaper changes, gentle cleansing of the diaper area after stooling (not necessary with urine alone), and avoiding application of occlusive materials over the diaper.

If the condition still does not resolve with the application of topical therapies as prescribed by the primary care doctor, the patient should be referred to a pediatric dermatologist to rule out other conditions, Dr. Paller says.

"Diaper dermatitis may be a manifestation of uncommon disorders in the infant ... particularly cystic fibrosis or zinc deficiency and the infiltrative condition Langerhans cell histiocytosis," Dr. Paller notes.