[Immunologic methods of study for evaluating the risk of anaphylactic reactions in intradisk chymopapain injections]

According to results available to date, skin tests are of limited value in determining the risk of anaphylactic shock. By identifying specific IgE antibodies, e.g. via the Chymo-FAST test or the corresponding RAST, the risk of anaphylactic shock of 0.2%-1% in the total group of patients can be reduced to 0.05% in patients in whom the test was negative, whereas in test-positive patients the risk is above 60%. Previous intolerance reactions among the remaining 0.05% are probably due to a non-testable pseudoallergic reaction, just like the 6% mild late reactions after the injection. For the remaining risk of 0.05% in IgE-negative patients drug prophylaxis with antihistamines or if necessary even steroids will continue to be mandatory. Examination of histamine release from leucocytes, which can be conducted in very few centres only, may possibly be able to clarify in future to what extent reinjection is permissible if a disc on a different level is affected, besides other scientific problems.