The relationship between nutritional status and serum soluble interleukin-2 receptor concentrations in patients with Crohn's disease treated with elemental diet.

Serum soluble interleukin-2 receptor concentrations (sIL-2R) were measured and correlated with indices of disease activity and nutrition in 13 patients with active Crohn's disease treated with an elemental diet. The initial serum sIL-2R concentrations were raised, 1121 +/- 181 U/ml (mean +/- SEM) compared to controls, 177 +/- 22.9 U/ml (n = 18) (p < 0.001). Four weeks' treatment resulted in significant improvement in disease activity (Harvey-Bradshaw index) and 4-day faecal (111)Indium-leucocyte excretion. Serum sIL-2R concentrations did not change significantly after treatment, 789 +/- 79.8 U/ml (p > 0.05). Serum sIL-2R concentrations were inversely correlated with albumin, pre-albumin, creatinine-height index and total body potassium. Only those patients with markedly elevated sIL-2R concentrations (>800 U/ml) and severe nutritional depletion prior to treatment, showed significant reductions in sIL-2R levels with elemental dietary treatment. These results demonstrate an association between nutritional impairment and immune activation in Crohn's disease.