NEW YORK (Reuters Health) – In children with severe atopic dermatitis prone to infections, a regimen of dilute sodium hypochlorite baths and intermittent intranasal mupirocin reduces disease severity, according to physicians at the Feinberg School of Medicine in Chicago.

"We and others have found anecdotally the addition of dilute sodium hypochlorite baths to be helpful in decreasing infection rates and disease severity" in children with eczema, Dr. Amy S. Paller and associates note, but theirs is the first controlled trial of this strategy.

Their study in the May issue of Pediatrics included 22 patients ages 9 months to 17 years with moderate to severe atopic dermatitis and bacterial skin infections. On average, one third of body surface area was affected, and the mean Eczema Area and Severity Index (EASI) score was 19.7. Lesions in most patients were positive for Staphylococcus aureus.

All patients were initially treated for 2 weeks with oral cephalexin, and continued topical anti-inflammatory medication and emollient therapy throughout the 3-month trial.

The 9 patients randomly assigned to the treatment arm bathed in a dilute bleach solution (0.5 cup of 6% bleach in 40 gallons water, final concentration 0.005%) for 5-10 minutes twice a week. Additional plain-water baths were not restricted. In this group, mupirocin ointment was applied intranasally twice daily for 5 consecutive days per month.

The 13 placebo patients bathed in plain water and used petrolatum instead of mupirocin.

Compared to the placebo group, the treatment group showed significantly greater improvement on the EASI scores: -10.4 vs -2.5 at 1 month (p = 0.017) and -15.3 vs -3.2 at 3 months (p = 0.004).

The percentage of body surface area affected also significantly declined in the treatment group, by 23.7% at 3 months, versus 3% in the placebo group, p = 0.004.

Tolerability to the dilute bleach baths was "excellent," the authors say, although early on, infected lesions were made more painful. One patient who complained of skin irritation stopped the baths. However, after he developed a methicillin-resistant S. aureus skin infection requiring hospitalization, he resumed treatment, with no reported adverse effects.

Active treatment did not eradicate S. aureus, however, leading Dr. Paller and her team to suggest that longer duration of this treatment strategy may be required.

Reference:
Pediatrics 2009;123:e808-e814.