Objective: This study was undertaken to investigate the value of Doppler flow measurements of the superior mesenteric artery (SMA) as a marker for disease activity in patients with Crohn's disease.
Subjects and methods: Duplex Doppler sonography measurements of SMA blood flow volume were obtained in 29 consecutive patients with suspected Crohn's disease. We prospectively sought a correlation between the independent assessment of Doppler flow measurements and markers for disease activity: Crohn's disease activity index and fecal alpha 1-antitrypsin clearance and our reference standard based on clinical history, physical examination, laboratory values, endoscopy, surgery, and follow-up.
Results: In 27 of 29 patients, adequate measurements of SMA blood flow were obtained. In 15 patients no disease activity was judged to be present or no Crohn's disease (n = 2) was found at follow-up (group 1). In 12 patients, activity of Crohn's disease was diagnosed (group 2) on the basis of the reference standard. In group 2 the Doppler SMA blood flow values were significantly higher (p < .05) than those for group 1 (826 +/- 407 ml/min versus 323 +/- 103 ml/min). Of the other parameters investigated, only the alpha 1-antitrypsin value correlated with the reference standard but to a lesser degree than the values for SMA blood flow measurement.
Conclusion: This prospective study shows that SMA Doppler blood flow measurements can be used to assess disease activity in patients with Crohn's disease. This approach may be of value in the diagnosis and follow-up of patients with Crohn's disease, providing directly available, quantifiable, noninvasive information on disease activity.