P22 Identifying treatment naïve and undiagnosed primary biliary cholangitis patients using a novel case finding database and treatment pathway

<h3>Introduction</h3> Primary Biliary Cholangitis (PBC) is a chronic under-diagnosed condition with treatment available. In the Somerset Liver Improvement Project (SLIP) we developed a unique case-finding tool (covering &gt;0.5M patients) enabling rapid longitudinal analysis of blood test results to identify cohorts at risk of liver disease. We aimed to a) identify patients who had blood markers suggestive of PBC, b) develop a recall treatment pathway co-designed with our public and patient reference group (PPRG) and c) offer clinical review and treatment where appropriate. <h3>Method</h3> Blood test results from 2005 to 2020 were analysed to a) identify the overall number of patients who had ever had a positive mitochondrial antibody (AMA) b) find those that had AMA reversal on last testing from positive to negative AMA (reverted) and c) identify patients aged 18–70 years with persistent positive AMA and Alkaline Phosphatase (ALP) above 130U/L to call to clinic. Patients unknown to us were invited to clinic. Those who attended had confirmatory blood tests. Communication materials were developed with our PPRG to maximise response rates. <h3>Results</h3> Our database showed 267 males with positive AMA at some point, 31 having reverted AMA on last testing. 951 females had a positive AMA at some point with 107 having reverted AMA on last testing. Overall, 40 patients (9M, 31F) met the criteria for clinic invitation. 20 responded to the invitation and were seen face to face in clinic with 18 having repeat blood tests (2 patients had already been started on treatment in another setting). 4 of those attending were patients who had been lost to follow up or previously discharged. Of the 18 patients to have repeat bloods, 10 had a positive AMA on repeat testing and 8 had reverted. 1 patient had reverted twice over time with the last result being negative. 10 patients were considered treatment naive and started on Ursodeoxycholic acid. <h3>Conclusion</h3> Our novel case finding database can be used to identify treatment naive and undiagnosed PBC patients. We achieved a 50% response rate and patients with PBC were commenced on treatment where appropriate. Variability in AMA status and liver enzyme levels emphasises the importance of longitudinal analysis of past blood results. The AMA reversion rate seen here has not been previously reported in the scientific literature to our knowledge. We demonstrated a powerful methodology for identifying and engaging treatment naïve patients with benefits for prognosis, and potentially for clinical trial recruitment.