Certain pediatric skin diseases more likely in children with skin of color

Chicago - Children with skin of color develop the same types of dermatoses as Caucasian patients, but there are certain disorders that occur with a greater incidence in youngsters with more darkly pigmented skin, said Patricia A. Treadwell, M.D., at the American Academy of Dermatology's Academy '05.

The list of dermatoses that are more common in children with skin of color includes transient neonatal pustular melanosis, acropustulosis of infancy, tinea capitis, dyspigmentation, lupus erythematosus and Kawasaki disease. Dr. Treadwell, assistant dean for cultural diversity, and professor of pediatrics, Indiana University School of Medicine, Indianapolis, reviewed some of the features of those disorders and considerations for diagnosis and treatment.

Diagnosing

"Histology will reveal an infiltrate of polymorphonuclear leukocytes, a specimen for culture will be sterile, and the eruption is self-limiting so that no treatment is needed," Dr. Treadwell says.

Acropustulosis of infancy usually onsets between six and 12 months of age and is characterized by the intermittently recurrent appearance of pruritic vesicopustules. The lesions of acropustulosis of infancy develop primarily on the hands and feet, although skin on the buttocks, trunk and extremities may also be involved. The diagnosis is established either clinically or by biopsy that will show subcorneal pustules with a neutrophilic infiltrate and occasionally eosinophils.

"There are a number of entities to consider in the differential diagnosis of this disorder, and often these children have been misdiagnosed as having scabies and treated with a scabicide," Dr. Treadwell notes.

Treatment

Acropustulosis of infancy can persist for years, but can be controlled with antihistamines and topical corticosteroids applied with or without occlusion. Dapsone may also be considered if a child is particularly symptomatic, but only after first screening for glucose-6-phosphate dehydrogenase deficiency.

Tinea capitis also occurs much more often in black children compared with Caucasians, although the reason(s) underlying that difference in prevalence remains unclear. Once the diagnosis is established, treatment requires an oral antifungal agent. A six to eight week course of griseofulvin remains the treatment of choice for Dr. Treadwell.

Azole antifungal agents, either itraconazole or fluconazole, as well as terbinafine represent second-line alternatives. The azoles are available in a liquid formulation while terbinafine is not. For infections caused by Trichophyton tonsurans, the most common pathogen in tinea capitis, a two to four week course of the azoles or terbinafine is adequate.

Prescribers should be aware Microsporum canis responds somewhat slowly to terbinafine.

Secondary skin disease

Children with skin of color are also especially likely to develop hypo-or hyperpigmentary changes after resolution of lesions of a dermatosis or secondary to other forms of skin trauma, including treatments administered for skin disorders.

"These pigmentary changes may be very distressing to the patient, particularly because they often resolve very slowly. Therefore, it is important to be cognizant of the effects of the various treatments we use and to discuss the possibility of pigmentary changes with the patient," Dr. Treadwell says.

While the peak incidence for onset of systemic lupus erythematosus (SLE) is in young adulthood, about 15 percent of cases first develop in children ages 9 to 15 years old. SLE in the pediatric age group occurs more commonly in blacks and other skin of color groups compared with Caucasians. Eighty percent of adolescents and young teens with SLE have cutaneous findings and so are likely to be seen by the dermatologist.

"In one-fourth of patients, the cutaneous findings are the presenting sign, and so the dermatologist has a role in the diagnosis of the systemic disease in these individuals," Dr. Treadwell says.