Small Duct Primary Sclerosing Cholangitis: An Underdiagnosed Cause of Chronic Liver Disease and Cirrhosis

Abstract

Classic or large duct primary sclerosing cholangitis (PSC) is part of the PSC spectrum. It is diagnosed on clinical and biochemical findings of cholestasis supported by biliary tree changes on cholangiography, forgoing the need for an invasive liver biopsy. The spectrum contains various PSC variants with distinct clinical courses and outcomes. We present a case of small duct PSC, a rare variant that manifested insidiously with clinical and objective cholestasis but appeared negative on diagnostic cholangiography. Eventually, a liver biopsy was obtained that revealed chronic bilious disease of the small and microscopic ducts with simultaneous changes consistent with liver cirrhosis. Despite presenting like its classical counterpart, small duct PSC can remain undetectable on cholangiography due to the diminutive size of the bile ducts requiring histological confirmation. In contrast to classic PSC, small duct PSC portends a much better prognosis. However, it eventually progresses to the classic form or end-stage liver disease, requiring patients to receive timely surveillance and transplantation referrals. Due to the limited understanding of this disease process, patients with similar presentations often pose a diagnostic dilemma due to the clinical and cholangiographic mismatch. This case aims to reaffirm that a negative cholangiography does not rule out the PSC spectrum and that small duct disease is a rare but growing entity. The paucity in cases emphasizes the importance of isolated reports in guiding workup and management, especially since surveillance schedules and transplantation guidelines have not been formally established.

Primary Sclerosing Cholangitis-Autoimmune Hepatitis Overlap Syndrome: Significant Barriers in Liver Disease Diagnosis and Treatment Experienced by the Latino Community

“…Her history was deeply influenced by SDOH including lack of an insurance policy, language barriers as she can only speak Spanish, and receiving no continuity of care for her disease upon diagnosis (Figure 2). These SDOHs led the way to a delay in diagnosis and treatment, commonly faced by Hispanic patients, as shown in previous reports [3,7,10,11]. These factors convey more importance in the public health aspect of liver disease where Latinos have been shown to have higher disease prevalence and complications.…”

“…Standard therapy is immunosuppression with corticosteroids and azathioprine, while ursodeoxycholic acid is sometimes combined [ 1 ]. If medical treatment for the primary needs is impractical or complications like cirrhosis develop, leading to end-stage disease, liver transplantation (LT) must be considered as the treatment of choice [ 1 , 2 , 7 ].…”

“…At the time of disease presentation, it is more common for Hispanics to show characteristics of advanced liver disease, including portal hypertension and its complications. Additionally, the response to ursodeoxycholic acid treatment is less effective in Hispanics, especially with a younger disease presentation [ 7 ].…”

“…Cholankeril et al describe data on patients with PBC on the liver transplant waitlist, where it was found that African American and Hispanic patients were younger compared to other ethnicities and presented a higher model for end-stage liver disease (MELD) score in the transplant list. When listing for the LT, they were also found to give more frequent complications such as ascites, hepatic encephalopathy, and spontaneous bacterial peritonitis [ 7 ].…”

The Space of Disse: The Liver Hub in Health and Disease

“…Chronic cholestatic liver diseases including primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are associated with active hepatic fibrosis, and ultimately cirrhosis. The progressive structural damage of the intrahepatic biliary three leads to cholestasis, which has been traditionally considered an important pro-fibrogenic factor [136]. In experimental models of cholestasis, fibrogenic markers like TIMP-1, α-SMA, collagen 1 and TGF-β, and accumulation of B-cells and T-cells in the portal tracts generate ROS and liver damage [137].…”