Dr Bergquist, Dr Lindberg, Dr Saarinen, and Dr Broomé undertook a study in order to investigate the familial occurrence of autoimmune diseases in a large group of patients with primary sclerosing cholangitis (PSC).
The research team included a total of 145 patients with PSC who had been treated at Huddinge University Hospital between 1984 and 1999.
For every patient with primary sclerosing cholangitis and inflammatory bowel disease (IBD, n=126), the researchers randomly selected a control patient with IBD (n=126), matched for age, sex and type of IBD.
The researchers asked all patients and controls to answer a questionnaire comprising information about autoimmune diseases among first-degree relatives.
The researchers identified 22 index cases with PSC from 21 families with a first-degree relative with either chronic liver disease and/or IBD.
| The prevalence of PSC among first-degree relatives was 1%.|
In siblings the prevalence was 2%
|Journal of Hepatology|
The research team found that 5 patients with PSC had a first-degree relative with PSC (3%).
In addition, the researchers noted that the prevalence of PSC among first-degree relatives was 1%. In siblings the prevalence was 2%.
The researchers found that the prevalence of first-degree relatives with autoimmune diseases outside the liver was similar in PSC patients and controls.
Dr Lindberg concluded, "First-degree relatives of patients with PSC have a PSC prevalence of 0.7%."
"This represents a nearly 100-fold increased risk of developing PSC compared with the general population, supporting the hypothesis that genetic factors are of importance for development of PSC."