238 The Use of MRCP in the Assessment of Choledocholithiasis in Patients Presenting with Symptomatic Gallstone Disease

Abstract

Abstract Aim Magnetic Resonance Cholangiopancreatography (MRCP) is the investigation of choice for choledocholithiasis; however, use is varied and guidelines vague. The National Institute for Health and Care (NICE) recommend MRCP when common bile duct (CBD) dilatation ≥ 8mm or liver function tests (LFTs) are abnormal but do not quantify this further. The Sunflower Study classifies patients as “high-risk” for choledocholithiasis if alanine aminotransferase (ALT) ≥ 80 IU/L, alkaline phosphatase (ALP) ≥ 200 IU/L or CBD ≥ 8mm. We aimed to assess compliance with NICE criteria and determine what biochemical abnormalities are most associated with choledocholithiasis. Method A retrospective analysis of inpatient MRCPs performed at QEH between March and May 2021 was performed (n = 72). Pre-MRCP bloods and imaging were used to assess concordance with NICE guidelines. We compared LFTs between patients with and without choledocholithiasis, looking for significant differences. Results 84.7% of MRCPs were performed in accordance with NICE guidance, of which 31.1% demonstrated choledocholithiasis. No cases of choledocholithiasis were identified if NICE criteria were not fulfilled. A significant difference between the mean values of gamma glutamyltransferase (GGT) and ALP was noted between patients with and without choledocholithiasis. Conclusions We identified that the majority of MRCPs were performed in accordance with guidance. Significantly, no cases of choledocholithiasis were identified if these criteria were not met. Although our sample size was small, we found the most specific biochemical markers were ALP and GGT and propose that further research with larger cohorts may help develop a risk stratification tool to aid decision making.