There is no general agreement regarding the assessment of disease activity in CD. The clinical index most frequently used is the Crohn's Disease Activity Index (CDAI), but its value is widely disputed. Most studies continue to use the CDAI because of the lack of a better index. Many complications of CD elevate the CDAI yet do not reflect active inflammation (4); this was illustrated by the increased stool frequency after small-bowel resection observed in our study. As we pointed out, all

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... s had stable body weights, no significant acute phase response (ie, normal C-reactive protein values), and no change in medication during the 3 mo preceding the study. This indicated that the patients included in the study were clinically in remission. Capristo et al suggested that patients with and without smallbowel resection should not be pooled to study nutritional or metabolic changes. However, we were interested in the nutritional status of a representative sample of patients with long-standing CD. Exclusion of patients with small-bowel resections would have greatly impaired the clinical value of such a study. Second, in our opinion there is no essential metabolic difference in small-bowel function between patients with small-bowel resections and those in whom a small-bowel segment has been destroyed as the result of a previous inflammation. In both cases, small-bowel function is impaired, eventually resulting in malnutrition. In our study, absolute daily fat intake was not significantly different between CD patients (35.1% of energy intake) and matched control subjects (33.6% of energy intake). Patients were clinically in remission and were not anorexic, in contrast with the patients in the study of Rigaud et al (5) who lost weight and reported decreased food intake. Although we did not measure energy metabolism directly, the patients in our study were presumably in energy balance because they all had stable body weights during the 3 mo preceding the study. It would be interesting from a scientific point of view, however, to measure energy expenditure in these patients because this may further our understanding of the pathophysiology of malnutrition in CD. Because of possible differences in daily total energy expenditure between patients and control subjects as a result of quantitative and qualitative differences in daily activities, the predictive value of resting energy expenditure measured by indirect calorimetry is limited. Hence, in this respect, the doubly labeled water technique seems to be the most adequate method (6).