Editorial comment: Readers should be aware that the content of this research paper has changed substantially from the version that was originally published on-line on 9 September 2009. A reappraisal of the data has resulted in substantial changes to the originally quoted reference ranges. One author of the originally posted article has disassociated herself from this final version of the paper.
AbstractObjective: Measurement of the faecal markers calprotectin, lactoferrin and tumour M2-PK has been reported to be useful in the diagnosis and management of a range of gastrointestinal disorders in both children and adults. The aim of this study was to investigate the requirement for age-related reference ranges. Methods: Faecal samples were obtained from 132 healthy subjects and analysis of calprotectin, lactoferrin and tumour M2-PK performed using commercially available enzyme-linked immunosorbent assay. Results: In the healthy subjects median concentrations were as follows: for calprotectin -2-9 y, 34 mg/g, 10-59 y, 22 mg/g and 60 y, 27 mg/g; for lactoferrin -2 -9 y, 2.2 mg/g, 10 y, 0.5 mg/g; and for tumour M2-PK all subjects ,1 U/mL. Significant differences between age groups for different markers resulted in the following age-related reference ranges: calprotectin -2 -9 y, ,166 mg/g, 10-59 y, ,51 mg/g, 60 y, ,112 mg/g; lactoferrin -2 -9 y, ,29 mg/g, 10 y ,4.6 mg/g.
Conclusion:In healthy individuals, we found there to be variation in the faecal inflammatory markers calprotectin and lactoferrin with age. For both calprotectin and lactoferrin children aged 2-9 y had significantly higher concentrations than subjects aged 10 y. For calprotectin but not lactoferrin, adults 60 years had a higher concentration than those aged 10-59 y. There was no change with age in the metabolomic marker faecal tumour M2-PK in healthy subjects. The knowledge of age-related reference ranges in healthy subjects is important to fully interpret changes in gastrointestinal disease.