Adverse effect of abdominal operations on production of interferon-gamma.

OBJECTIVE: To assess the effects of abdominal operations on the production of cytokines as one of the mechanisms of postoperative immunosuppression.
DESIGN: Prospective study.
SETTING: University hospital, Belgium.
SUBJECTS: 19 Selected patients who underwent operations for benign (n = 10) or malignant (n = 9) diseases.
INTERVENTIONS: Whole blood was collected in heparinised tubes before operation and on postoperative days 1, 2, 3, 5, 7, and 9. After 1/10 dilution in culture medium the whole blood cells were stimulated with 5 micrograms/ml phytohaemagglutinin and 25 micrograms/ml lipopolysaccharide, and incubated at 37 degrees C in 5% carbon dioxide. Concentrations of interleukin 1 (IL-1), tumour necrosis factor alpha (TNF alpha), and interleukin 6 (IL-6) were measured at 24 hours, and interferon-gamma and interleukin 2 (IL-2) were measured at 72 hours, with commercially available assays.
OUTCOME MEASURES: Production of the monokines IL-1, TNF alpha, and IL-6, and of the lymphokines IL-2 and interferon-gamma, postoperatively. The monokines were expressed as a percentage of the preoperative values/monocyte, and the lymphokines as a percentage of preoperative values/lymphocyte.
RESULTS: Production of IL-1 and TNF alpha, but not IL-6, decreased immediately after operation then returned to preoperative values. Production of IL-2 and interferon-gamma were significantly reduced immediately after operation, and that of interferon-gamma was still depressed on the ninth postoperative day.
CONCLUSION: Cytokine production is altered after abdominal operations. The production of interferon-gamma may be a more sensitive indicator of altered immune response and vulnerability to infections and tumour growth than concentrations of other cytokines.