The "in vitro skin test": a reliable and repeatable assay of immune competence in the surgical patient.

In vitro blast transformation of human peripheral lymphocytes was tested using standard skin test antigens, the mitogens PHA and Con A, and the mixed lymphocytes reaction. The study group included 15 patients with multiple trauma, 40 with major burns, six following cholecystectomies, six following aortic reconstruction, and 30 normal volunteer controls. Repeated skin testing may sensitive patients to candida and streptokinase-streptodornase (SKSD), and desensitize them to mumps antigen. Blast transformation in response to PPD did not correlate with the clinical status of the patients; similarly, blast transformation in response to stimulation by the mitogens PHA and Con A could not reliably predict the occurrence of septic complications. Reactivity in response to stimulation by the soluble antigens SKSD and mumps and in the one-way mixed lymphocyte reaction accurately predicted the clinical course of patients. This method of "in vitro skin testing" is a reliable and repeatable method of monitoring the immunologic status of patients whose illness or injury requires longitudinal study.