Contact dermatitis of the lips due to late-type sensitization against dalbergiones in a wooden recorder

Background: Late-type sensitizations against wood are rare and are mostly seen in patients with occupational contact with saw dust. Generally, commercial wooden products only lead to sensitization or dermatitis in cases when contact to the unprotected skin is direct, intensive and of longer duration, i.e. by wearing wooden jewelry or by playing wooden instruments. Causative for the sensitization process are ingredients of the wood core such as alkaloids, glycosides, anthrachinones, saponines, phenols, catechols, flavonoids, cumarins, and benzo-, naphtho-, furano-, and phenanthrenquinones and their precursors. Case report: We report the case of a 70-year-old patient who developed cheilitis after playing different wooden recorders made of African blackwood, rosewood, cedar, olive, and pear. Methods: Patch testing with baseline series of contact allergens and saw dust of the recorders were performed as well as skin prick tests with common inhalant allergens and saw dust of the recorders. Results: Patch testing showed sensitizations against African blackwood, rosewood, fragrance mix 2 and hydroxyisohexyl-3-cyclohexene carboxaldehyde. Skin prick testing was without pathological results. Conclusion: African blackwood and rosewood contain (S)-4’-hydroxy-4-methoxydalbergione and (S)-4-methoxydalbergione. As a result of the chemical affinity between the dalbergiones, cross-reactions between different woods are observed. The case presented shall show the diagnostic procedure in cases in which sensitizations against wood components are suspected.