Prevailence of Patch Test Positivity with Some Bases

Abstract

To evaluate the suitability of some chemicals to act as bases for antigens for patch tests, patch tests were performed with these agents in patients having contact dermatitis. Propylene glycol'used as such produced positive reactions in 25 (50%) patients of which 12 were 2 + or more, polyethylene glycol 200 produced positive reactions in 9 (18%) cases of which 4 cases were 2 + or more, a mixture of liquid paraffin and hard paraffin gave rise to positive reactions in 10 (10%) cases 3 of these being 2 +, a mixture of liquid paraffin and bees wax was positive in 14 (14,Yo) cases 3 of these being 2 +, yellow petrolatum was positive in 4 (8%) cases, one of which was 2 +, white petrolatum was positive in S (6%) cases all of these being + reactions only, and glycerol gave rise to a I + reaction in only one (2%) caw. In tropical countries, water should be as base for as many antigens as possible for others, a control test with the b must be included.