Allergy Testing of Multiple Patients with a Common Syringe

To the Editor: Lutz et al. (May 17 issue)* demonstrated bacterial contamination of syringes used for intradermal skin testing after contaminated needles had been removed from the syringes. The contamination apparently occurred when relatively small volumes of Escherichia coli broth were inadvertently aspirated into the syringe when the needles were changed. The authors correctly raise concern regarding the use of single syringes with multiple needles for intradermal skin testing of more than one patient, However, in our office, we tested an alternative technique for changing needles on skin-test syringes. Before the needle is removed from the syringe, approximately 0.05 ml.