Urinary neopterin, a marker of clinical activity in patients with Crohn's disease.

Urinary neopterin excretion was measured in 34 patients with Crohn's disease. Neopterin excretion showed a significant correlation with disease activity using a clinical activity score. An interacting effect of previous medical or surgical therapy on neopterin excretion could be ruled out. Disease localization and extent did not exert any influence on neopterin excretion. Neopterin values were significantly correlated with disease duration, body weight and the presence of a palpable abdominal mass. Multiple stepwise regression analyses identified the combination of neopterin, hematocrit, weekly stool frequency, palpable abdominal mass and related symptoms as predicting clinical activity better than Crohn's Disease Activity Index (CDAI). Thus, neopterin determination may be introduced as an additional biochemical parameter in the assessment of disease activity.