RETROGRADE COLONIC SPREAD OF A NEW MESALAZINE RECTAL ENEMA IN PATIENTS WITH DISTAL ULCERATIVE-COLITIS

Background: Rectal treatment with mesalazine enemas is the first-line therapy for distal ulcerative colitis. In order to improve the benefit s of rectal therapy, a new 60 mL 5-ASA rectal gel enema preparation ha s been developed using a device which excludes direct contact of the i nert propellant gas with the active drug. The purpose of the present s tudy was to assess by scintigraphy the colonic distribution of this ne w mesalazine rectal gel enema. Methods: Twelve patients with active ul cerative colitis were administered 4 g of the mesalazine rectal enema labelled with 100 MBq technetium sulphur colloid (Tc-99m-SC). Anterior scans of the abdomen were acquired at intervals for 4 h. Scans were a nalysed to evaluate the extent of retrograde now and homogeneity of di stribution of the radiolabelled enema in the rectum, sigmoid, descendi ng and transverse colon. In addition, plasma levels of 5-ASA and Ac-5- ASA were measured for 6 h. Results: All patients retained the entire r ectal gel throughout the course of the study without reporting adverse events. In 11 out of 12 patients (92%) the gel had spread homogeneous ly beyond the sigmoid colon and had reached the upper limit of disease in all cases. The maximum spread (splenic flexure) was observed in 6 out of 12 patients (50%) within the first 2 h. The systemic absorption of mesalazine and its metabolite Ac-5-ASA was low. Conclusions: The n ew mesalazine enema represents an adequate alternative and a further t echnological improvement in the topical treatment of distal ulcerative colitis.