Barium enema preparation: a study of low-residue diet, "Picolax' and 'Kleen-Prep'.

A prospective, randomized three-arm trial is presented of 150 consecutive patients attending for double-contrast barium enema (BE). This compares 'Picolax' (a combined stimulant and osmotic agent), 'Picolax' following a 3 day low-residue diet and 'Kleen-Prep' (a polyethylene-glycol osmotic agent). Faecal clearance, mucosal coating and colon fluid were scored in four colonic segments by two radiologists working independently and blinded to the preparation used. Analyses of an elderly subgroup and of side effects was performed. Low-residue diet conferred no benefit to Picolax preparation, which was satisfactory (ability to exclude 5 mm polyps) in 80% of patients. Kleen-Prep failed to achieve adequate preparation in 46%, due to excess fluid and poor mucosal coating. Kleen-Prep caused more patient nausea, abdominal bloating and pain than Picolax. Patients 70 years and older had similar results. Low-residue diet need not be used in addition to Picolax. Kleen-Prep as a single agent is not recommended for BE preparation.