F. Menezes Brandão

Contact dermatitis to Disperse Blue 106

9 patients with typical textile dermatitis were found to be allergic to dark polyester blouses. Thin‐layer chromatography of the dyes extracted from the fabrics identified the presence of several dyes, from which Disperse Blue 106 was positive in all patients.

Sensitivity to thimerosal and photosensitivity to piroxicam

17 patients allergic to thimerosal. with no previous history of photosensitivity or piroxicam ingestion. 2 patients with piroxicam‐induced photosensitivity, and 10 controls were patch or photopatch tested, with 1 or more of the following thimerosal, thiosalicylic acid, irradiated and non‐irradiated solutions of piroxicam alone, L‐cysteine alone and piroxicam plus l‐cysteine, and piroxicam in petrolatum, The results of the tests supported the hypothesis that there are cross reactions between thiosalicylic acid and piroxicam, a photosensitizer. The mechanism of the cross‐reactions may involve photoproduts of piroxicm and L‐cysteine, as patients allergic to thiosalicylic aid, who have positive photopatch tests to piroxicam, also had positive patch tests to the irradiated solution of piroxicam plus L., cysteine.

Allergy to oil of turpentine in Portugal

Oil of turpentine is still a common allergen in Portugal although it does not contain Δ3‐carene, as ascertained by gas chromatography. Patch tests with 6 terpenes on 22 patients revealed that 17 were allergic to α‐pinene and 15 to dipentene: 12 were allergic to both. 4 patients were sensitive to Δ3‐carene, 3 to α‐terpineol and 2 to β‐pinene. These results explain the incidence of allergy to oil of turpentine in Portugal.

Photodermatitis from anthraquinone

All the cases reported so far m the literature refer to employees m either pharmaceutical or vetennary laboratones, where they were m close contact with the vitarrun. However, our patient had only slight contact with it m p1g feed m1xes, where vitamm K3 accounted for only about 0.13% and 0.2% of the total m1xture. What 1s surpnsmg m th1s patient 1s the rapid sensitization and the very acute climcal picture he presented, probably elicited mamly by airborne contact. References