Antidiphtheritic immunization using sodium ricinoleate as a detoxifying agent.

The property of sodium ricinoleate to detoxify bacterial toxins has been pointed out in previous papers. 1 , 2 We have studied this problem further to determine whether it is possible to immunize children and adults against diphtheria with toxin which has been detoxified in this way.

A quantity of toxin was mixed with a 1 per cent solution of sodium ricinoleate, so that each cc. of the mixture contained 0.125 L+ toxin. Immediately after mixing, 1 cc. of the mixture was injected subcutaneously into the arms of a group of laboratory workers and volunteer medical students. In all the cases there developed a local redness with some induration, which persisted for five or six days. There were no general reactions observed. Another group was injected with like amounts of soap toxin which had stood at room temperature for six hours to allow the soap-toxin to come to equilibrium. In this group there were either no local reactions or mild reddening at the point of inoculation. No general reactions were observed. In another group, injected with soap-toxin which had stood at room temperature for twelve hours, there were no local reactions.

One hundred forty-nine cases of children and adults with positive Shick tests have been treated with one dose of soap-toxin. Sixty-nine of these have been retested within six weeks after treatment. Of this group 50.2 per cent gave negative skin reactions. We have frequently found the Shick test to be negative as early as four weeks after inoculation.

We wish to emphasize the importance of using only toxinsoap solutions which are perfectly clear. Injections of cloudy solutions are invariably followed by severe local reactions. This point has been emphasized in an earlier publication in which animal experiments were reported. 2