Mesenteric blood flow is related to disease activity and risk of relapse in ulcerative colitis: a prospective follow up study

Background-The diagnostic significance of increased splanchnic blood flow i n ulcerative colitis is unclear. This prospective study was therefore under taken to define the role of Doppler sonography in the assessment of disease activity and in the prediction of early relapse. Subjects/Methods-Splanchnic flowmetry was performed in 76 patients with ulc erative colitis (47 with active disease and 29 in remission), six with infe ctious colitis, and 13 healthy controls during fasting and 30 minutes after ingestion of a standardised meal. Twenty seven of the patients with ulcera tive colitis and all patients with infectious colitis were investigated dur ing the active state as well as in clinical remission and followed up for s ix months. Flow velocity and pulsatility index (PI) of the superior (SIMA) and inferior (IMA) mesenteric arteries and the portal vein were related to clinical (Truelove index), laboratory (C-reactive protein), and endoscopic (Sutherland index) parameters of disease activity. Results-The mean flow velocity of the IMA correlated closest with clinical activity (Truelove, r = 0.41, p < 0.005), the PI with C-reactive protein (r = 0.30, p < 0.05), and endoscopic activity (r = 0.45, p < 0.001). All pati ents in remission after six months (14/14) or with infectious colitis (6/6) showed an increase in PI of the IMA compared with the initial measurement during active disease (mean increase for ulcerative colitis +36% and for in fectious colitis +77%). In contrast, most patients with later relapse or su rgery (11/13) had decreased PI during initial remission (mean decrease -12% ). The positive predictive value of this index for maintenance of remission was 0.77. Flow variables of the SMA and portal vein displayed weaker corre lations. Conclusions-Flow measurements in the IMA are closely related to clinical an d endoscopic disease activity in patients with ulcerative colitis. Repeated measurement of the PI allows estimation of the risk of recurrence.