Allergic Contact Sensitivity in Atopic Dermatitis

TLDR

Atopic dermatitis may reflect a defect in cell‑mediated immunity, leading to resistance against Rhus sensitization that could arise from immunologic unresponsiveness, epidermal abnormalities, or genetic factors. The study examined Rhus contact sensitivity in 171 adults, including 40 with atopic dermatitis. Only 3 % of atopic patients and 15 % of patch‑test‑positive atopics showed Rhus dermatitis, compared with 37 % of healthy controls and 61 % of control patch‑test positives, and a second test revealed that 6 % of nonsensitive atopics versus 31 % of nonsensitive controls had become sensitized by the first test.

Abstract

Allergic contact sensitivity to<i>Rhus</i>was investigated in 171 humans, 40 of whom had atopic dermatitis. Rhus dermatitis was found in only 3% of the atopic subjects, while 37% of healthy nonatopic controls claimed to have had rhus dermatitis. Survey patch tests with rhus oleoresin were positive in 61% of controls but in only 15% of atopics. A second rhus patch test revealed that 6% of nonsensitive atopics and 31% of a nonsensitive control group had been sensitized by the first patch test. Resistance of individuals with atopic dermatitis to sensitization by rhus may be an example of immunologic unresponsiveness or due to an epidermal abnormality, and is possibly under genetic control. Atopic dermatitis is hypothesized to be a phenotypic marker for a defect in the human's cell-mediated immune system.