Before reacting to any single value, check whether it is outside the interval by an amount larger than the assay's own variation.
Haemolysis in the sample raises potassium and several enzymes spuriously. If a result is bizarre, ask whether the sample was flagged before building a theory on it.
A twenty-analyte panel run on a healthy person will produce, on average, one out-of-range result purely from how reference intervals are constructed. That is arithmetic rather than pathology.
External quality assurance schemes document between-laboratory differences on common analytes that routinely exceed the size of clinically interesting changes.
Decide the action for each result before you order the test.
edited 26 Apr 2025 by Dr_Marek_Zielinski — reworded for clarity after a comment