The natural history of pruritus in primary biliary cirrhosis (PBC) is unclear.
In this study, researchers from Rochester, Minnesota, evaluated outcomes of pruritus in clinical trials for ursodeoxycholic acid (UDCA).
The team found that in a UDCA-placebo trial, which was begun in 1988 and included 180 subjects, there was a 55% prevalence rate for pruritus.
They identified serum alkaline phosphatase level and Mayo risk score as independent risk factors for pruritus.
|Serum alkaline phosphatase level and Mayo risk score are independent risk factors for pruritus.|
|Clinical Gastroenterology and Hepatology|
Among the placebo-treated patients, the annual risks for development or improvement/resolution of pruritus were found to be 27% and 23%, respectively.
In the UDCA-treated patients there was a trend toward improvement after 1 year (30%), compared to placebo (23%). This was not observed at 2 or 3 years.
In a further UDCA trial begun in 1995, which included 155 subjects, the overall prevalence of pruritus was found to be 37%. This was significantly lower than in the 1988 trial.
The team found that this study also identified baseline serum alkaline phosphatase level and Mayo risk score as independent risk factors for pruritus.
Of the 13 patients with refractory pruritus, symptom resolution, or improvement, occurred with the use of oral rifampin (300 or 600 mg daily).
However, 2 patients treated with rifampin developed biochemical evidence for hepatotoxicity.
Dr Jayant Talwalkara's team concluded, "Although less prevalent among recently diagnosed individuals, more than one third of PBC patients develop pruritus".
"No significant risk reduction in developing pruritus with UDCA therapy was observed compared to placebo-treated patients".
"The long-term administration of rifampin for refractory pruritus is associated with occasional hepatotoxicity".