Apparent diffusion coefficient can predict Crohn disease activity: A systematic review and meta-analysis

Zielsetzung The aim of this retrospective study was to analzye the relationships between apparent diffusion coefficient (ADC) and different activity parameters of Crohn disease (CD), e.g. length and wall thickness, CRP, fecal calprotectin (FCP), magnetic resonance index of activity (MaRIA), Crohn disease activity index (CDAI), endoscopic activity score (SES-CD), histologic inflammatory activity score, and histological fibrotic score.

Material und Methoden We screeened MEDLINE library, SCOPUS and EMBASE data bases for association between ADC and activity parameters of Crohn disease in patients with Crohn disease up to May 2021. 21 studies with 1053 patients were included in the analysis. We extracted the following data from the literature: number of patients, correlation coefficients between ADC and length as well as wall thickness, CRP, FCP, MaRIA, CDAI, SES-CD, histologic inflammatory activity score, and the histological fibrotic score. Associations between ADC and activity parameters of Crohn disease were analyzed by Spearman's correlation coefficient.

Ergebnisse In the overall sample, the pooled correlation coefficient between ADC and CDAI was -0.8, (95% CI=[-0.94; -0.65]), between ADC and MaRIA -0.66, (95% CI=[-0.79; -0.53]). A strong association was observed between ADC and SES-CD with a pooled correlation of -0.66, (95% CI=[-0.87; -0.46]). Correlations between ADC and histologic inflammatory score was -0.51, with histologic fibrotic score 0.49. Correlations between ADC and blood inflammatory markers were -0.35 for CRP and -0.59 for FCP.

Schlussfolgerungen ADC showed strong inverse correlations with CDAI, MaRIA, and SES-CD scores. ADC has a limited capacity to indicate systemic inflammation or to assess fibrotic changes in the bowel wall. It appears that ADC can reflect acute bowel inflammation but not systemic inflammation in Crohn disease.

Publication History

Article published online:
13 April 2023