Influence of surgery, age and serum albumin on delayed hypersensitivity.

Delayed hypersensitivity was assessed with four antigens, viz. purified protein derivative of tuberculin (PPD), Candida albicans, streptokinase/streptodornase and mumps, 48 hours before and 24 hours after elective major abdominal surgery in 24 patients. Cumulated areas of skin response were recorded on the basis of readings 24 and 48 hours after antigen stimulation. A control group of 16 patients was similarly assessed, but without surgery between the two test occasions. Retesting in this control group increased the cumulated skin response area in all patients. The respective means for the two tests were 1 290 +/- 222 to 2 330 +/- 365 mm2 (p less than 0.0001), demonstrating a pronounced booster action by the initial test. In contrast, the surgical patients showed a decrease, from 1 559 +/- 203 preoperatively to 1 230 +/- 210 mm2 postoperatively (p = 0.14). The postoperative response was significantly lower than the retesting response in the controls without surgery (p = 0.02), indicating that surgery leads to depression of delayed hypersensitivity response. The preoperative cumulated skin test response correlated with age (r = -0.66, p less than 0.001) and with serum albumin (r = 0.59, p less than 0.01). Postoperative depression of the skin test response also was related to age (r = 0.53, p less than 0.01) and with postoperative fall in s-albumin (r = 0.51, p less than 0.05). The results emphasize that interpretation of serial skin testing in surgical patients is not adequate unless comparison is made with a similar retesting regimen in nonsurgical patients.