map_loinc_to_snomed
Enter a LOINC code to get guidance on where to find LOINC to SNOMED CT mappings.
Instructions
This tool looks up a LOINC code in NLM Clinical Tables and returns guidance on where to obtain a LOINC → SNOMED CT mapping. It does not perform the mapping.
Direct LOINC → SNOMED CT mappings are not freely available via API. UMLS Metathesaurus contains the relationships but requires an individual UMLS Terminology Services license; the LOINC SNOMED CT Expression Association is published by Regenstrief Institute as part of the LOINC release and requires authenticated download from loinc.org under the LOINC license.
For programmatic LOINC → SNOMED mapping, use UMLS or the LOINC Expression Association files. For interactive lookup, use the SNOMED CT browser available to your organization or the Regenstrief RELMA desktop tool.
Provide a LOINC code like "2339-0" (Glucose) or "718-7" (Hemoglobin).
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| loinc_code | Yes | LOINC code (e.g., 2339-0 for Glucose) |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
| loinc_code | Yes | The LOINC code as submitted. | |
| loinc_details | Yes | NLM Clinical Tables details for the LOINC code (component, system, property, etc.). Null when the code was not found upstream. | |
| status | Yes | Always "guidance-only" — direct LOINC → SNOMED CT mappings require licensed sources (UMLS Metathesaurus or LOINC SNOMED CT Expression Association). This tool returns pointers, not the mapping itself. | |
| guidance | Yes | Short human-readable explanation of why this tool returns guidance instead of a mapping. | |
| mapping_sources | Yes | Structured list of authoritative LOINC → SNOMED CT mapping sources (UMLS Metathesaurus, LOINC SNOMED CT Expression Association, Regenstrief RELMA). |