Dear Sirs
We would like to clarify the assignment of the LOINC Code 88880-0 to MDW® parameter (UniCel DxH 900, Coulter Cellular Analysis System, Beckman Coulter).
Currently the code 88880-0 is assigned to Monocyte distribution width
(Property: EntVol; Example_Units: fL; Shortname: MDW Bld Auto)
But the UniCel DxH 900 parameter MDW (Monocyte distribution width) not expressed in units. Being a parameter measuring the standard deviation of a cell population (monocytes) but derived from a multidimensional scatter plot. As certified in the official IFU. Source : UniCel DxH 900 Series with System Manager Software Coulter Cellular Analysis System Early Sepsis Indicator (ESId) Application Addendum PN C21894AD (April 2023)
With this difference in units, I understand that I cannot use code 88880-0 for this parameter. Do you think the same?
Is there a specific coding for expressing this parameter as standard deviation without units?
Beckman Coulter does not offer me another LOINC code alternative.
We look forward to your clarification or alternative coding or if it is necessary to request a new LOINC code for this parameter
Hello & Welcome to the Forum! I did some initial scanning of literature for scatter plots and the claim of no reporting unit. I understand there are variables identified to determine what the scatter plots will hold, and that the cells will perform in some way against those variable observations to identify what part of the plot they belong in. Something still tells me there’s numeric value in there, which may be accompanied by a unit of measure. Even if it’s just the arbitrary “U”. I’m going to ping the Lab LOINC Committee with this entry and see other perspectives. Bear with me for a time. If they agree, I can help you make a submission for a different MDW term. Best regards, Pam
LOINC Code 88880-0 is assigned to “Monocyte distribution width” with the property “EntVol,” example units “fL,” and shortname “MDW Bld Auto.” The MDW parameter on the UniCel DxH 900 measures the standard deviation of a monocyte population derived from a scatter plot and is not expressed in volumetric units. FC Scatter plots have the axes which represent the intensity of light scattered at different angles (forward scatter and side scatter), so arbitrary units (AUs) because they are relative measurements dependent on the specific settings and calibration of the flow cytometer. The FSC signal can be used to estimate cell size, but it does not provide a direct measurement of diameter in micrometers (µm) or femtoliters (fL).
I think there is a discrepancy in units and the measurement Pam. LOINC Code 88880-0 may not be suitable for this parameter. The MDW parameter, being a standard deviation measurement without specific units, requires appropriate code to reflect its unique characteristics accurately.
We night need to revisit additionally 32207-3, 74452-4, 21000-5 which are all the same.
Regarding your questions:
Agreement on Code 88880-0: I concur that Code 88880-0, defined for volumetric measurements, is not appropriate for a parameter representing the standard deviation of a cell population derived from a scatter plot without specific units.
Alternative Solutions: Beckman Coulter does not offer an alternative LOINC code for this parameter, it might be necessary to request the creation of a new LOINC code. This new code should reflect the nature of the MDW parameter as a unitless standard deviation derived from the scatter plot.
