From the Guidelines
Inflammatory bowel disease (IBD) is strongly correlated with liver inflammation, with up to 30% of patients experiencing altered biochemical liver tests and 5-10% developing primary sclerosing cholangitis (PSC) or other liver disorders. The connection between IBD and liver inflammation stems from shared immune-mediated inflammatory pathways and the gut-liver axis, where intestinal inflammation can affect liver function through portal circulation 1. Patients with IBD, particularly ulcerative colitis and Crohn's disease, have an increased risk of developing various liver disorders, including PSC, autoimmune hepatitis, and non-alcoholic fatty liver disease.
Some key points to consider in the correlation between IBD and liver inflammation include:
- The prevalence of PSC in extensive colitis IBD is around 5% 1
- A concomitant diagnosis of PSC in IBD is often overseen and the prevalence underestimated, with screening using MRCP revealing an increase in prevalence from 2.2% to 7.5% in one large population-based study 1
- The strong association between PSC and IBD is well established but varies geographically, with the highest prevalence in Northern Europe (around 80%) 1
- IBD in PSC represents its specific phenotype, characterized by a high prevalence of pancolitis, a mild disease course, predominant inflammation on the right side and rectal sparing, pouchitis, and a high risk of developing colorectal cancer 1
Regular liver function tests are recommended for IBD patients, especially those on hepatotoxic medications, to enable early detection of liver abnormalities. Managing both IBD and liver inflammation simultaneously often requires a multidisciplinary approach involving gastroenterologists and hepatologists to optimize treatment outcomes 1. Medications used to treat IBD, such as azathioprine, methotrexate, and infliximab, can also cause drug-induced liver injury, further complicating the relationship between IBD and liver inflammation.
In terms of specific recommendations, annual surveillance colonoscopy with biopsies is recommended in all adult PSC-IBD patients regardless of the duration of IBD or liver transplant status 1. A diagnostic colonoscopy can be considered every 5 years in people with PSC where no IBD is present or whenever complaints suspicious for IBD occur 1.
From the Research
Correlation between IBD and Liver Inflammation
- Inflammatory bowel disease (IBD) has been associated with primary sclerosing cholangitis (PSC), a chronic progressive disease that causes liver inflammation 2, 3, 4, 5, 6.
- The prevalence of PSC in IBD patients is estimated to be around 60-80% in western countries, suggesting a strong correlation between the two conditions 2.
- Studies have shown that patients with PSC-IBD have a distinct clinical phenotype, with an increased incidence of pancolitis, backwash ileitis, and rectal sparing 6.
- The gut-liver axis plays a crucial role in the pathogenesis of PSC-IBD, with gut inflammation influencing the liver through immune cells and the microbiota, and the microbiota in the gut modifying bile acids produced by the liver 4.
Clinical Implications
- The association between IBD and PSC has important clinical implications, including an increased risk of malignancies, such as colorectal cancer and cholangiocarcinoma 2, 6.
- Lifelong annual surveillance colonoscopy is currently recommended for patients with PSC-IBD to monitor for colorectal neoplasia 2, 6.
- Liver transplantation is the only potential curative therapy for PSC, but it carries a risk of PSC recurrence, worsening of IBD activity, and de-novo IBD occurrence after transplantation 2, 5.
Pathophysiology
- The exact pathophysiology of PSC-IBD is still unclear, but it is thought to involve a complex interplay between genetic and environmental factors, including the gut microbiota and immune system 3, 4, 5.
- Further studies are needed to understand the underlying mechanisms of PSC-IBD and to develop effective therapeutic strategies for this condition 2, 3, 4, 5, 6.