The following information was updated in the Lab Catalog.
November 2022
Influenza cases numbers are currently increasing throughout West Michigan. Influenza prevalence guides the most appropriate testing approach and sufficient prevalence has now been reached for influenza rapid antigen testing (e.g. Sofia instrument) to have improved performance. The use of rapid antigen testing as a screening method during high prevalence reduces both the cost to the patient and turn-around-time as compared to lab-based molecular methods. Rapid antigen tests generally have high analytical specificity, but lack the sensitivity of nucleic acid amplification methods (e.g. PCR). For this reason, PCR testing is still recommended for hospitalized patients and for outpatients with a negative antigen result if influenza is still suspected and if the result will impact clinical decision making.
Starting November 29th, 2022, Corewell Health West, Hematology Laboratories will begin reporting absolute counts for white blood cell (WBC) manual differentials, in addition to relative (percentage) counts. The WBC differential count determines the number of each type of white blood cell present in the blood. It can be expressed as a percentage or as an absolute value. Of these, the absolute value is much more important than the relative value, given that clinically relevant WBC elevations and declines are defined by their absolute numbers, not by their relative proportions, and there is potential for error if this conversion is performed outside the laboratory.
Effective November 21, 2022, the following changes will be made to Meconium Drug Testing (LAB479).
- The cutoff for positivity for the opiate drug class (codeine, morphine, hydrocodone, hydromorphone, oxycodone, and oxymorphone) will increase to 20 ng/g from 10 ng/g.
- The format of reporting will be updated to include discrete reporting fields for all tested analytes. Positive results will no longer be denoted via comments.