Frequency of indeterminate colitis in children and adults with IBD - a metaanalysis.

BACKGROUND

Indeterminate colitis (IC) remains an enigmatic inflammatory bowel disease (IBD) phenotype. It is currently not clear whether it constitutes merely a problem of terminology, classification, or possibly an early stage of IBD distinct from Crohn's disease (CD) and ulcerative colitis (UC).

METHODS

We analysed epidemiological data of studies comparing IC, UC and CD. We selected 14 studies investigating paediatric patients (10 prospective and 4 retrospective) and 18 studies investigating adult IBD patients (11 prospective and 7 retrospective) for this analysis.

RESULTS

Compared to adults (n=15,776) the frequency of IC is higher in children (n=6262) (children 12.7% versus adults 6.0%, p<0.0001). This difference between children and adults has been detected irrespective whether prospective or retrospective studies were selected. In both, children and adults IC was more frequent in prospective studies compared to retrospective studies (children p=0.0004; adults p=0.0024).

CONCLUSIONS

IC has been detected in a substantial proportion of paediatric patients with IBD. IC is more frequently found in children compared to adults. Further studies are required to clarify whether IC represents an IBD phenotype associated with childhood disease onset or whether the high IC frequency is due to difficulties in establishing a UC or CD diagnosis.