Which of the following findings is typical for primary biliary cholangitis?

In primary biliary cholangitis, increased alkaline phosphatase is a hallmark laboratory finding. This condition is characterized by the autoimmune destruction of the small and medium-sized bile ducts within the liver, leading to cholestasis and ultimately biliary fibrosis. As the bile accumulates, alkaline phosphatase levels rise, reflective of impaired bile flow.

This elevation is significant in diagnosing primary biliary cholangitis, as alkaline phosphatase is an enzyme that is primarily synthesized in the liver and its elevation indicates biliary tract obstruction or damage. While other liver enzymes may also be elevated, alkaline phosphatase is particularly associated with cholestatic liver diseases such as this one.

The other options do not typically correlate with the disease. Increased serum creatinine would suggest renal impairment, which is not a characteristic finding of primary biliary cholangitis. Decreased bilirubin levels are not expected, as bilirubin levels can be normal or elevated due to cholestasis. Similarly, decreased alkaline phosphatase would contradict the pathology of primary biliary cholangitis, where one expects to see an increase due to the underlying cholestatic process. Thus, the elevation of alkaline phosphatase is indicative of the disease and aids in its diagnosis.