RESUMO
BACKGROUND: The woods of trees of the genus Dalbergia are a frequent cause of allergic contact dermatitis. OBJECTIVES: To describe the different patterns of symptoms and sensitisation to woods of the genus Dalbergia in four patients whose regular work is linked to music, either as performers (two patients) or instrument makers. RESULTS: The patients showed extensive cross-reactivity between the different Dalbergia woods. The two musicians exhibited symptoms exclusively in the contact areas, while the instrument makers showed a pattern of airborne symptoms. The period from sensitisation to the development of symptoms varied greatly among the patients. CONCLUSIONS: The symptoms of allergic contact dermatitis to Dalbergia woods differ markedly depending on the route of contact. Cross-reactivity between the woods of this genus is very wide. The sensitising potential varies between the various Dalbergia woods, which require different contact periods depending on their sensitising power.
RESUMO
BACKGROUND: Iodinated contrast media produce non-immediate hypersensitivity reactions (NIHR). The goal of this prospective study was to determine the utility of skin tests and the subsequent tolerance to negative skin-tested iodinated contrasts in patients with NIHR caused by iomeprol. METHODS: Prick and intradermal tests with iomeprol, iopamidol, iopromide, and iobitridol were performed in all patients. IV challenge with the causative contrast (iomeprol in 90%) was made if skin tests were negative. In case of a positive skin test with the causal contrast, or a positive challenge test with it, IV challenge test with an alternative, negative skin-tested contrast was performed in all patients. RESULTS: Skin tests were positive in 47.6% (20/42) of patients with NIHR induced by iomeprol. Of the 66 challenge tests performed with negative skin-tested iodinated contrasts, tolerance was confirmed in 35 (53%): 32 iomeron, 2 iobitridol, 1 iopamidol. Cross-reactivity between iomeprol and iopamidol was 22% (4/20 in patients with positive skin tests and 5/21 in patients with negative skin tests). CONCLUSIONS: Sensitivity of the skin tests was less than 50% NIHRs due to iomeprol, while the negative predictive value of skin tests in patients who tolerated challenges with alternative contrasts (mainly iopamidol) was 53% (35 tolerated out of 66 performed). The cross-reactivity between iomeprol and iopamidol is high.