DISCREPANCY IN PATCH TEST-RESULTS WITH WOOL WAX ALCOHOLS AND AMERCHOL(R) L-101

Wondering why Amerchol(R) L-101 (containing wool wax alcohols obtained from the hydrolysis of wool fat) appears as a test material (100%) in a cosmetics series (Chemotechnique Diagnostics AB), as wool wax alcoh ols were already tested in the European standard series, we added Amer chol(R) L-101 (100%) systematically to the standard series. From 8 Apr il 1991 to 28 February 1992, a total of 393 patients were tested: 3.05 % (n=12) showed positive test results (+, ++, +++) for wool wax alcoho ls as well as Amerchol(R) L-101 (100%), 0.3% (n=1) for wool wax alcoho ls only, and 11.1% (n=44) for Amerchol(R) L-101 (100%) only. Thus, the positive tests for Amerchol(R) L-101 (100%) had a higher frequency of 3.4 compared to those for wool wax alcohols. In the meantime, we also added Amerchol(R) L-101 50% (Trolab) to the standard series. Of all p atients tested (n=223) 2.7% (n=6) had positive reactions to wool wax a lcohols and 12.1% (n=27) to Amerchol(R) L-101 100% and/or 50%. Thus, p ositive reactions to Amerchol(R) L-101 (100% and 50%) were 4.5 higher, whereas the rate of concordancy decreased. It is remarkable that 8 pa tients only had a positive reaction to Amerchol(R) L-101 50% and 9 onl y to Amerchol(R) L-101 100%. It seems that we miss many diagnoses in c ontact allergy by using only the standard wool wax alcohols test (30%) . (C) Munksgaard, 1997.