EFFECT OF HIGH-DOSE CHEMOTHERAPY ON INTESTINAL PERMEABILITY IN HUMANS

1. Mucositis is a common side-effect of chemotherapy which is difficul t to assess except by invasive means such as upper gastrointestinal en doscopy. Differential absorption of mono- and di-saccharides, such as rhamnose and lactulose, is a non-invasive measure of intestinal damage , 2. The purpose of the study was to assess the duration and severity of intestinal damage in patients undergoing high-dose chemotherapy and autologous blood stem-cell transplantation for malignant disease, 3. Thirty-five patients were studied before treatment and at 7, 28, 60 an d 90 days after treatment. 4. The median lactulose/rhamnose ratios bef ore treatment and at 7 and 90 days post-treatment were 0.09, 0.62 and 0.06 respectively. Altered permeability was due to both increased lact ulose permeation and decreased rhamnose absorption. These abnormalitie s suggest a defect in tight-junction integrity as well as a decrease i n surface area of small bowel. 5. We conclude that chemotherapy given for malignant disease is associated with a transient abnormality in in testinal sugar permeability, which peaks at 7 days after treatment and is composed of both mono- and di-saccharide absorption abnormalities.