Grevillea robusta (Silver-Oak) Dermatitis

Abstract

We have reported on three patients who developed an allergic contact dermatitis to silver-oak sawdust. Silveroak, Grevillea robusta A. Cunn. is native to eastern Australia but has been introduced to the warmer areas of the United States and to many tropical and subtropical countries. The allergens found in G robusta species are resorcinols. Silver-oak contains primarily 5-tridecylresorcinol (grevillol) and smaller amounts of 5-pentadecyl and 5-pentadecenylresorcinol. Grevillea species share common antigens with Philodendron species, which have also caused contact dermatitis. Silver-oak dermatitis occurs commonly in woodworkers, but their spouses are also susceptible from contamination of the home environment. The clinician must test with appropriate dilutions of sawdust and allergens to rule out false-positive patch test results.