[Energy losses from a short bowel: not only fat]

Two adult patients, men aged 43 and 45 years, with Crohn's disease, complicated by high-output small-bowel-stomy and short-bowel syndrome due to several intestinal resections, presented with extreme weight loss. Although both patients followed a high-calorie diet combining solid foods and enteral nutrition by nasogastric tube, containing 16,000 kJ and 21,000 kJ, respectively, weight loss continued. Faecal fat excretion and basal metabolic rate were determined, but these could not explain the caloric deficit. Therefore, faecal bomb calorimetry, a measurement of total faecal energy content, was also performed, revealing a considerably higher faecal energy loss than had been calculated from faecal fat excretion; this indicates that faecal carbohydrate loss plays an important supplementary role. A stable weightwas achieved in both patients by prescribing extra food. Therefore, faecal fat excretion is an insufficient indicator of total faecal calorie loss in patients with high-output stomata and short-bowel syndrome. Bomb calorimetry may be considered as a tool to determine the remaining absorptive capacity in short-bowel patients.