Purpose: The aims of this study are to describe normal colon transit time (CTT) in healthy children, correlate results with age, the Bristol stool scale, and stool frequency, and to evaluate intra- and interobserver variability.
Methods: Inclusion criteria were as follows: healthy children between 3 and 18 years old with a normal defecation pattern, no history of abdominal surgery, and no medication use. Total and segmental CTT is measured by taking ten polythene radiopaque markers during six consecutive days followed by a single abdominal X-ray on day 7. Total and segmental CTT are calculated by multiplying the number of markers by 2.4 (Abrahamsson et al. Scand J Gastroenterol 32:72-80, 1988).
Results: Fifty-four children and adolescents have participated: 30 boys and 24 girls (median age 10 years (3-18 years)). Median total CTT is 36 h (<2.4-86.4 h). There is no significant difference for age category (toddlers 31.2 h (<2.4-74.4 h), elementary school 36 h (2.4-79.2 h), and adolescents 43.2 h (14.4-86.4 h)). Segmental CTT reveals a median right colon CTT of 4.8 h (0-28.8 h); a median left colon CTT of 2.4 h (0-31.2 h); and a median rectosigmoidal CTT of 24 h (0-64.8 h). The Bristol stool scale correlates with total CTT (p = 0.031). The intra- and interobserver variability displays an ICC of 0.999 for the total CTT.
Conclusion: The CTT of normal healthy children is not sex- or age-related (above the age of 3 years). The Abrahamson method for CTT measurement by using bony landmarks for the determination of colon segments is easy to perform and well tolerated with a virtual inexistent rating difference between different observers.