Delayed hypersensitivity skin testing does not influence the management of surgical patients.

Delayed hypersensitivity skin testing was performed at weekly intervals on 95 patients with major surgical illness. Patients with abnormal reactions on initial skin testing had a higher mortality than those who were normal initially (p less than 0.01), but this was not due to a greater rate of major septic complications. Significantly higher rates of sepsis (p less than 0.001) and mortality (p less than 0.001) were found in patients with abnormal reactions at any stage of their illness compared with patients who remained normal throughout. However, careful study of the temporal relationship between skin reactions and clinical events in individual patients suggested that these differences were not of value in clinical practice. Abnormal reactions usually followed obvious complications, such as sepsis or secondary hemorrhage, rather than predicted them. Deterioration of skin reactions from normal to abnormal was observed on 32 occasions in 25 patients but preceded the development of sepsis in only four patients.