Skin signs of systemic illness in children

San Francisco - Biologic drugs developed for treating psoriasis and other conditions also can help treat skin signs of systemic illnesses in children, says an expert.

"In the last 10 years," Amy E. Gilliam, M.D., says, "a number of new biologic agents have been approved for use in adults, and they're now being used increasingly for a variety of indications in children."

She says she considers these agents very promising for use in children because they possess comparable efficacy and better long-term safety profiles than conventional alternatives.

Kawasaki disease

Biologics appear helpful in treating Kawasaki disease (KD), which she says is inflammatory in nature although its true pathogenesis remains unknown. Its symptoms include perineal desquamation, particularly in the acute phase, that's often mistaken for severe diaper dermatitis

Dr. Gilliam reports that within the past year, diagnostic criteria for KD have been revised. Previously, these criteria included fever persisting for at least five days and at least four of the following symptoms - polymorphous exanthem, bilateral conjunctival injection, mucous membrane changes, acute nonpurulent cervical lymphadenopathy and changes in peripheral extremities.

"Now, because clinicians are making the diagnosis of KD much more rapidly, cases with even four or fewer febrile days - shortened by treatment with intravenous immunoglobulin (IVIG) - have been proposed to be equivalent to cases with five or more febrile days (Ayusawa M et al. Pediatr Int. 2005 April;47(2):232-234.)," she says.

Recent associations researchers have made with KD include onset of psoriatic lesions during KD's acute and convalescent phases (Boralevi F et al. Ann Dermatol Venereol. 2003 May; 130(5):528-531.), Dr. Gilliam adds.

Standard of care

Dr. Gilliam says the standard of care for treating KD involves giving 2 g/kg IVIG as a single infusion, along with aspirin 80 mg/kg to 100 mg/kg per day divided into four daily doses.

More recently, she says, researchers have reported promising results with infliximab at a dose of 5 mg/kg.

"Dr. Jane Burns and her colleagues have reported the use of infliximab in a series of 17 patients with refractory KD, and they found that most of these children responded rapidly and completely to the single infusion of infliximab without any adverse events (Burns JC et al. J Pediatr. 2005 May;146(5):662-667.)," she tells Dermatology Times.

As for the pathogenesis of KD, Dr. Gilliam says researchers believe the disease stems from an infectious trigger in genetically susceptible children.

"Because they have this genetic susceptibility," she explains, "it is thought that an abnormal immunologic response is triggered by an environmental agent, which results in inflammation of the blood vessels."

Other systemic illnesses

Juvenile dermatomyositis (JDM), on the other hand, involves a heliotrope rash in 50 percent to 90 percent of cases, Dr. Gilliam says. It's marked by erythema, edema of the face and sometimes swelling of the eyelids and can be mistaken for atopic dermatitis (AD) or an acute allergic reaction, she adds.

Dr. Gilliam says distribution of this rash distinguishes JDM from AD.

"The rash of JDM usually overlies the joints of the hands, as opposed to AD, which one sees more commonly in a flexural distribution, such as in the antecubital or popliteal fossae," she explains. These "Gottron's papules" occur over the metacarpophalangeal (MCP)/interphalangeal (IP) joints as well as on the elbows, knees and malleoli, Dr. Gilliam says.