Add AI UCUM

[Susan]

Please add the UOM AI for Avidity Index to the UCUM standard for the autoimmune antibody testing (LUPUS) Ribosomal P SM RNP SSA/SSB SCL-70 Thyroid Peroxidase A

[Gunther Schadow]

Would you have a literature reference? I have Googled and can not find the unit "Activity Index" described.

[Gunther Schadow]

I have verified your user account, so from now on you can comment directly on the tickets.

Thanks for your reply. You wrote:

Quest Diagnostics reports AI (avidity index) on their autoimmune antibody test which uses Immunoassay. It can also be called Affinity Index as I've seen these two terms used interchangeably.

The literature can be found here:

• ​http://www.ncbi.nlm.nih.gov/mesh/?term=avidity
• ​http://www.ncbi.nlm.nih.gov/pubmed/3944471
• ​http://jcm.asm.org/content/49/7/2610.long

[Gunther Schadow]

Aha, first I have misread, "avidity". Sorry for that mistake.

So, now we just need to find a crisp definition of the Avidity Index as a unit. Particularly, can you speak about how much avidity index values are comparable between the Abbott assay and another company's assay? Or is it an Abbott specific measure?

Also, would you consider whether AI is not really a unit at all. AI is an index, an observation. You need a LOINC code for it for sure (is there one?) And once you have a LOINC code, why do you need a unit?

[Christof Gessner]

Rejected.

There are a number of LOINC codes that measure "avidity" as a ratio. One example is: 81119-0 Also there are a number of Lupus-related tests.

Please transfer to the LOINC committe in charge.

[Brenée Mitchell]

Decision from 17 February 2021 Board meeting:

Reject - Not a UCUM code request, it is an avidity measure and can be captured within a LOINC term.

No response will be sent due to the age of the request.