When an amylase result is 550 U/L and a 1:4 dilution gives 180 U/L, what should the technologist report?

In this scenario, the initial amylase result is given as 550 U/L, but a further 1:4 dilution yields a result of 180 U/L. Understanding how to interpret these results involves knowledge of dilution calculations.

When a dilution is performed, the results need to be corrected to reflect the concentration in the undiluted sample. A 1:4 dilution means that the original sample is diluted to a volume four times greater than the original, effectively dividing the concentration by 4. Therefore, to find the equivalent concentration in the undiluted sample, you would multiply the diluted result by the dilution factor.

In this case, since the diluted result is 180 U/L and the dilution factor is 4, the calculation would be:

180 U/L (diluted result) x 4 (dilution factor) = 720 U/L (recalculated amylase concentration in the original sample).

This value should be reported as the amylase level, as it accurately reflects the concentration in the original, undiluted specimen. Reporting the 720 U/L is essential to ensure clinical decisions based on the correct amylase level.