New LOINC Codes for Reporting Lyme Modified Two-Tiered Testing (MTTT)

Hi,
this may be the further mappings referred to above, but 101358-0 is a nominal LOINC. What are the answers going to be?
In Regenstreif I see the example answer list is LL6315-7:
IgG- and IgM- |  |  | LA33615-8  - not reportable in CT, any positives are
IgG- and IgM+ |  |  | LA33616-6
IgG+ and IgM- |  |  | LA33617-4
IgG+ and IgM+ |  |  | LA33618-2

Thanks in advance and sorry for my ignorance!

Nancy,
currently the interpretations differ slightly between manufacturers and also we are trying to align with APHL guidance (that last part has slipped through the proverbial cracks - I am fishing it back out and will post the updated document here by end of this week).
For the nominal LOINC so far I have this:
IgG- and IgM - = No evidence of infection. In case of clinical uncertainty (presence of tick bite or neurological symptoms), the patients should be followed up during time. = map to either a new code for "no serological evidence of prior exposure or infection" or 260415000^Not detected^SCT

IgG – and IgM + = Probable infection at an early stage. = map to: a new code for "serological evidence of probable infection at early stage"

IgG+ and IgM- =  Probable infection at any stage. = map to: a new code for "serological evidence of probable infection at any stage"

IgG+ and IgM+ = Probable acute infection. = map to: a new code for "serological evidence of probable acute infection"

Labcorp reports the MTT with separate tests.  First test is IgG and IgM combined, resulted as Ordinal so positive or negative.  If positive, it reflexes to separate IgG and IgM tests, with both reporting as Ordinal, pos/neg.  
The last is the Final Interpretation which is reported as Nominal and uses one of the following SNOMEDs.
 710604009     Immunoglobulin M antibody to Borrelia burgdorferi 
 710389009     Immunoglobulin G antibody to Borrelia burgdorferi 
 120714000     Borrelia burgdorferi antibody   (when pos IgM and IgG)
 38434005       No confirmation of    (Not reported to most states)

Thanks Carmen - I will take a look at these, too. Are you using LOINC 101358-0 for the Final Interpretation?
Riki

Yes, effective late yesterday, 3/14/23.  I haven't been able to find a SNOMED that indicates presence of IgG and IgM, so I just went with the B. burgdorferi Ab.  Not as specific as I would like, but was the best option.
Carmen  

Hi,
Some updated info that may help. With Riki's review, we told a lab to add these 2 SNOMEDs for more specific reporting of the 101352-3 results.  Our mapping currently looks like:

    | 101352-3  | Borrelia burgdorferi Ab.IgG and IgM with reflex to immunoassay panel - Serum or Plasma  | 10828004  | Positive  OR alternate result | 720735008  | Presumptive positive

 | 40612-4  | Borrelia burgdorferi IgM Ab [Presence] in Serum or Plasma by Immunoassay  | 10828004  | Positive

 | 16480-6  | Borrelia burgdorferi IgG Ab [Presence] in Serum or Plasma by Immunoassay  | 10828004  | Positive

Could we get the different manufacturers and related LOINC-SNOMED combos at some point?

I am trying to get some guidance here, as APHL also had guidance on how to interpret the MTTT - but they have 2 levels - the lab interpretation and the provider interpretation:
Bold is package insert for DiaSorin as an example:
IgG- and IgM - = No evidence of infection. In case of clinical uncertainty (presence of tick bite or neurological symptoms), the patients should be followed up during time. 

APHL guidance lab interpretation = Negative for AB to B. burgdorferii (Lyme disease)

APHL guidance provider interpretation = No laboratory evidence of infection with B. burgdorferii (Lyme disease)

APHL guidance lab interpretation = IgM-class antibodies to B. burgdorferi (Lyme disease) detected

APHL guidance provider interpretation = Results are consistent with acute or recent infection with B. burgdorferi (Lyme disease)

My original proposal to code to "serological evidence of probable infection at early stage" 

APHL guidance lab interpretation = IgG-class antibodies to B. burgdorferi (Lyme disease) detected

APHL guidance provider interpretation = Results are consistent with B. burgdorferi (Lyme disease) infection in the recent or remote past. IgG-class antibodies may remain detectable for months to years following resolution of infection.

My original proposal to code to "serological evidence of probable infection at any stage" 

 

APHL guidance lab interpretation = IgM and IgG-class antibodies to B. burgdorferi (Lyme disease) detected

APHL guidance provider interpretation = Results are consistent with B. burgdorferi infection (Lyme disease) in the recent or remote past. Antibodies may remain detectable for months to years following resolution of infection

 
Carmen is using codes from the substance hierarchy to indicate the detection of the specific antibodies, I would prefer to have codes in the finding hierarchy for those, if we are chosing to codify the lab interpretation.

Maybe we can discuss on the national ELR call today and decide what we want to use.

Hi all - I'm the guest host this month for the ELR call. I think we can add this topic, at least briefly. Maybe also on one of the Thursday extended calls as well?

Thanks
Nancy