Final answer:
An elevated serum lipase level would support the diagnosis of suspected acute pancreatitis.
Step-by-step explanation:
When reviewing the client's laboratory results to support the diagnosis of suspected acute pancreatitis, an elevated serum lipase level would be the most indicative finding. Lipase is an enzyme produced in the pancreas, and an elevated level suggests pancreas inflammation. Elevated serum bilirubin levels and decreased serum trypsin or amylase levels are not specific to pancreatitis and may be indicative of other conditions.