This page includes all the relevant LOINC content changes to align with the LOINC Ontology, a collaboration between Regenstrief Institute and SNOMED International. These changes will be listed on this page for each new LOINC release starting with version 2.79.

We encourage you to review guidance regarding the LABORDERS.ONTOLOGY concepts added in the version 2.81 release.

The list below, arranged in reverse chronological order, contains all the individual changes that LOINC terminology applied in order to support computer readability of LOINC Parts, to apply post-coordination, and to clean up where needed to avoid redundancy, duplication, and consistency in expression or meaning.

Changes in version 2.83

  • Post-coordinated concepts in Microbiology genetics tests.
  • The concatenated values of gene mutation test and the method used in COMPONENT are separated in this version to display the gene mutation in COMPONENT and the targeted gene mutation analysis in METHOD.
  • Replacement of SYSTEM:XXX with {specimen} in Microbiology genetics tests.
  • Initial Clinical LOINC concepts set in LOINC Ontology version 2.83.

Changes in version 2.82

  • In collaboration with SNOMED International, we revisited all LOINC concepts in Class: Coagulation. It resuled in a combination of:
    • Components were revised and in the process Method as in Microviscometry and/or Technique as in “Factor induced” or “with excess phospholipids” were separated from Component and moved to Method. This project gave these concepts consistency in representation, better naming, and representation for use in post-coordination form.
    • A modeling project on how to create a consistent representation of coagulation observations in LOINC.
  • LOINC Components representing antimicrobial agents, their concentrations for susceptibility testing with “Method for Slow-growing mycobacteria,” cannot be defined in SNOMED CT. Therefore a new technique was created, removed from the Component Part as in “sulfiSOXAZOLE“ and added to Method as in “Method for Slow-growing mycobacteria.antibiotic concentration at 300.0 ug/mL” .
  • We improved representations of substances that are part of the Top 20,000 lab observables in LOINC, provided better representation of substance versus class (Antihistamines versus Histamine-H1 receptor antagonist), added Ag in Component Part where it should be represented and was missing.
  • Considerable maintenance work continues to add clarity to the content, and provide cleaner concepts for better computability, reduced errors, duplication, and improved standardized terminology:
    • Resolved duplication as result of identifying synonyms, related names, and correcting typographical errors
    • Deprecating old Part descriptions and replacing them with newer names (i.e. scientific names, changed and deprecated names) which resulted in cleaner LOINC Long Commong in some concepts
    • Continued effort in separating Component (Analyte) from Method in Component Part, the same effort is applied for Component with System

Changes to LOINC Parts in version 2.81

  • A clean-up project of stain techniques in LOINC – Method LPs took place as result of the collaboration work with SNOMED. The project addressed techniques needing adjustments (Hemosiderin stain) and removal of duplicate descriptions (Hall’s stain, Fouchet satin, etc.).
  • Component LP where analytes are either synonyms or represent an older description of a substance were updated. Several sources were used ChEBI, PubCHem, and Human Metabolite Database (Allo-tetrahydrocortisol and 5-apha-tetrahydrocortisol).
  • Component LPs that are very high level and clinically not useful were removed and their concepts deprecated.
  • Description of LPs were refined and made more precise. As result we eliminated duplication, and if not, then we added clarification to the description to separate between similar parts (Gliadin Ab and Gliadin peptide Ab; ).
  • Component LPs containing pesticides were replaced with insecticides to reduce ambiguity.
  • Continued the effort to clean the Component description by removing “Identified”, removing polymorphonuclear cells, separate Component from Method, and spelling errors.

Changes from LOINC version 2.79

  • This is a specific fraction case where the denominator is percentage or /100. Because the logic is that the fraction is captured by Property: NFr (Numeric Fraction), and by Unit: % (percentile), therefore, it is redundant to include “100” in the component, and the fraction is represented without prefix “100” in the denominator.
  • Hematocrit as a Component is not an expressive description for a ratio. Hematocrit is kept as a synonym, and the actual component is expressed as: Erythrocyte/Specimen.
  • eGFR measurement representation in LOINC has changed. Component: Glomerular filtration rate, Method: …/1.73 sq.M among non-black population or …/1.73 sq.M among black population, and similarly extended to other part of the Component descriptions.
  • Component where the description is property like as in Color, Appearance, Osmolality have changed to Component: Observation, and Property: Color, or Appearance, or Osmolality, and so forth, keeping the challenge and/ or adjustment in the Component description.