Elementary school (7-12 y) Colon transit time in healthy children S. Vande Velde, A. Notebaert, S. Van Biervliet, R. De Bruyne, M. Van Winckel Department of Pediatric Gastroenterology, Ghent University Hospital (UZG), Belgium Purpose 1 Aim of the study: describe normal Colon Transit Time (CTT) in healthy children, correlate results with age, Bristol stool scale and to evaluate intra-en inter-observer variability. Methods Inclusion criteria : - healthy children 3 to 18 years old normal defecation pattern no history of abdominal surgery or medication use Total and segmental CTT: 10 polythene radio-opaque markers during 6 consecutive days abdominal X-ray on day 7 total and segmental CTT are calculated by multiplying the number of markers by 2.4 [1]. Results Boys Girls Total Toddlers (3-6 y) 11 5 16 Elementary school (7-12 y) 10 9 19 Adolescents (13-18 y) 30 24 54 median age 10 y (3-18 y) median total CTT is 36h (0-86,4h) no difference for age category bristol stool scale correlates with total CTT (p=0,031) results are not different from CTT values in an adult population intra- and inter-observer variability displays an ICC of 0,999 for the total CTT Segmental CTT Right colon Left colon Rectosigmoid colon Total colon Median Upper limit Upper limit 3-6 years 2,4h 21,6h 26,4h 14,4h 52,8h 31,2h 74,4h 7-12 years 7,2h 28,8h 4,8h 19,2h 24h 55,2h 36h 79,2h 13-18 years 16,8h 9,6h 64,8h 43,2h 86,4h Total 19,8h* 26,4h* 63,0h* 79,2h* Conclusion The CTT of normal healthy children is not sex nor age related (above the age of 3 years). The Abrahamson’s method for CTT measurement using bony landmarks for determination of colon segments is easy to perform and well tolerated with a virtual inexistent rating difference between different observers. References 1. Abrahamsson H, Antov S, Bosaeus I (1988). Gastrointestinal and segmental colonic transit time evaluated by a single abdominal x-ray in healthy subjects and constipated patients. Scand J Gastroenterol 32:72-80.