Rapid amylase and lipase determinations by nephelometry.

The Coleman 91 nephelometer provides rapid, simple amylase and lipase assays, which are particularly suited to emergency requests. Linearity of amylase compares favorably with that of the Phadebas assay, and comparable precision was obtainable with serum and urine. Normal ranges for serum amylase are slightly higher than those based on the amyloclastic end-point assay. The serum lipase assay shows improved linearity over titrimetric procedures, although kinetics remain variably non-linear. Occasional sera show discordantly elevated nephelometric lipase and normal titrimetric lipase. Precision of the nephelometric lipase assay is somewhat lower than that of amylase; normal ranges are considerably higher than those based on titrimetry. Extremely lactescent sera may yield falsely low nephelometric amylase and lipase activities: these sera must be serially diluted to achieve actual values.