Platinum salts prick tests

R. Merget, G. S. Weminghaus, F. Bode, E. M. Bergmann, W. Zachgo, J. Meier-Sydow, Quantitative skin prick and bronchial provocation tests with platinum salt, Br. J. Indust. Med., 48 (1991), 830D837. 

Figure 4.1. Probability of platinum refinery workers remaining skin prick test negative to complex platinum salts, by smoking and exposure categories (reproduced from Calverley et a., 1995, with permission).

Little is known about the actual hapten-carrier linkages of the halide platinum salts except for their affinity for proteins in general and for sulphydryl bonds in particular. There is some limited evidence of sensitisation of rats by injection of platinum-protein conjugates (Khan et al. 1975). Such conjugates are not effective for skin prick tests and studies of platinum-human albumin conjugates have shown the presence of 26 platinum molecules for every 10" molecules of albumin. Under these conditions steric hindrance and paucity of available platinum-specific determinants are probably responsible for the poor eliciting capacity of such conjugates. 

Passive transfer tests with the sera of six sensitive refinery workers were made with unheated serum for IgE, long-term sensitising antibody and with heated serum for short-term sensitising, presumably IgG antibody to prick tests (Pepys et al. 1979). Table 5 shows positive reactions with all of the unheated sera in one or more of the three human Prausnitz-Kiistner recipients and with two and probably three of the sera in Prausnitz-Kiistner tests in the monkey. These findings support the possibility of specific IgE antibodies to the platinum salts. 

Exposure to chloropalatinates can give rise to immunologic contact urticaria, accompanied by asthma and rhinitis ( platinosis ). Cases of allergic contact dermatitis due to occupational exposure to platinum or platinum compounds were first reported in the 1950s (Levene 1971). In a more recent study (Baker et al. 1990), 28% of former employees had a positive prick test to platinum salts. They were not patch tested and the dermatitis reported could, in fact, have been an expression of contact urticaria. 

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