Critical assessment of small bowel biopsy in children.

176 biopsies of small bowel mucosa taken during a 5-year period from 162 children were reviewed, and 92 of them were subjected to quantitative measurement using surface/volume ratio and intraepithelial lymphocyte counting. There was good general agreement between stereomicroscopical appearance of fresh tissue, routine pathology reporting, and our independent histological assessment. Most of those in which there was divergence of opinion (11--15%) had intermediate mucosal changes. There was a significant difference between the surface/volume ratio for each of the three grades of histology (P less than 0.001, less than 0.001, less than 0.01), indicating a relationship between qualitative and quantitative methods of assessment. The range of measurements in intermediate biopsies overlapped those of the other two grades. In the 92 biopsies there was a correlation between surface/volume ratio and intraepithelial lymphocyte count (r = -0.56; P less than 0.001) which may reflect our clinical experience, in that 88% of the biopsies were graded as either normal or flat (probable coeliac disease). Very short children had shorter villi than those with nonspecific diarrhoea and a more normal height.