LOINC Snomed link

Hi All,

Can one LOINC be linked with more than one snomed. And if this is the case what does that mean about the result.



Hi Razina,

Your question brought three scenarios to mind. Two of the scenarios have to do with answers encoded to SNOMED CT. Any of the microbiology LOINC terms with PRID property, such as 81655-3 Respiratory pathogens DNA and RNA identified in Respiratory specimen by NAA with probe detection, have an example answer lists containing types of organisms found, and each of them would have a SNOMED CT term. Example answers for 81655-3 are No organism(s) detected, Influenza A (H3N2), Adenovirus, Parechovirus, and much more. If more than one organism’s DNA is found, there are more than one SNOMED CT term in the answer.

The second scenario is of post coordination of phrased answers. LOINC term 36903-3 is testing for Chlamydia trachomatis & Neisseria gonorrhoeae DNA; example answers here are phrases: Chlamydia trachomatis detected; Chlamydia trachomatis not detected. Multiple SNOMED CT terms would need to be used for the organism and the qualifier.

The third scenario pertains to the composition of the LOINC Parts to a single LOINC term. Translating each LOINC Part to its SNOMED CT counterpart brings up a post coordinated expression, of which there’s been two subset file releases for public review in recent years. More explanation of post coordinated expressions can be found at https://confluence.ihtsdotools.org/display/DOCSTART/7.+SNOMED+CT+Expressions

With an abundance of possibilities, I’m not sure there’s an easy answer to your second question “what does that mean about the result.” Clinically, I wouldn’t be able to speculate. Theoretically in format, I would say it means the result has complexity.

Have a great day, Hope this helps



Could you provide more information about your use case/need?

In addition to what Pam wrote, LOINC is used for lab orders and lab results, while SNOMED CT can be used for qualitative results values associated with Lab results, organisms for culture result values, as well as specimen type for a lab order or result, or specimen source for lab results such as pathology testing or cultures. They can all be “linked” in the HL7 message fields, although they are not all “linked” per he LOINC Lists and LOINC Answers to the LOINC code due to their differences.

Further information would help us better address your question.