Magnetic Resonance Cholangiopancreatography for Cholangiopathy After Pediatric Liver Transplantation: A Retrospective Analysis and Correlation With Clinical Outcome

BACKGROUND: Magnetic resonance cholangiopancreatography (MRCP) is used to analyze anastomotic strictures (AS) and non-anastomotic strictures (NAS) after pediatric liver transplantation (LT). We aimed to determine the incidence and severity of AS and NAS after pediatric LT by means of MRCP, and to correlate these to clinical outcome severity.

METHODS: All children who underwent an LT in our center at age < 12 years between 2010 and 2022 were identified, and those who underwent MRCP were included. Next, two abdominal radiologists retrospectively graded AS (none/< 50%/≥ 50% stenosis) and NAS (none/mild/moderate/severe) on these MRCPs. After consensus, the grades of AS and NAS were correlated with incremental grades of severity of clinical outcomes, with a focus on non-invasive and invasive procedures. This was done for short- (≤ 3 months) and long-term follow-up.

RESULTS: Out of 216 LTs at age < 12 years old, 25.5% (55/216) underwent MRCP after LT (median age 2.6 years; IQR 0.7-5.8 years). In the entire LT population, 24.1% (52/216) had some degree of AS or NAS on MRCP, of which 19.4% (42/216) had at least one significant abnormality (≥ 50% AS or moderate/severe NAS). In 6.0% (13/216) the combination of both moderate/severe NAS and ≥ 50% AS occurred. No correlation between AS/NAS severity and clinical outcome severity was observed.

CONCLUSIONS: Incidences of high-grade AS and moderate/severe NAS after pediatric LT were considerable. However, AS/NAS severity on MRCP did not correlate with the severity of clinical outcomes.