ORPHAcodes
Orphanet Nomenclature Pack

The Orphanet nomenclature is a multilingual, standardised, controlled medical terminology specific to rare diseases, that includes all clinical entities registered in the  Orphanet knowledge base. Each clinical entity (disorder, group of disorders, or subtype of a disorder) is associated with a unique numerical identifier named an ORPHAcode, as well as a preferred term, synonyms, and a definition.

The Orphanet nomenclature pack compiles a series of files (listed below) providing the necessary information to achieve implementation of ORPHAcodes in health information systems, and ensure easier and accurate coding. The files are updated every year in July to reflect the evolution of knowledge. Differential files are also provided to ensure traceability*.

The Orphanet nomenclature pack is released in 9 different languages: Czech, Dutch, English, French, German, Italian, Polish, Portuguese and Spanish. Excel and PDF files are available in English and are common to all Orphanet nomenclature pack**.

Orphacodes files are available via the CC BY 4.0 licence.

If you have any questions about tools, you can post an issue on our GithubTracker issue

* As per recommendation of the RD-ACTION working group for routine maintenance of codification.

** other languages (Chinese, Turkish and Ukrainian) are available in the Orphadata website.

The Orphanet nomenclature pack includes the following files:

• Orphanet nomenclature file ( XML Schema Definitions and JPEG representations for this file).
• Orphanet to ICD-10 ( XML Schema Definitions and  JPEG representations for this files) and ICD-11 mapping files ( XML Schema Definitions and  JPEG).
• Orphanet classifications files by medical specialities ( XML Schema Definitions and JPEG representations for these files).
• Linearisation file attributing one preferential medical specialty to every clinical entity ( XML Schema Definitions and JPEG representations for this file).
• Master file (Excel file), the minimal set of ORPHAcodes, aligned with ICD-10 codes, that should be used for data sharing and statistical purposes at EU-level. More information about the Master file can be found here.
• Orphanet nomenclature differential file (Excel file) which provides the key changes made to the nomenclature compared to the previous version.
• Description file ( PDF file describing the xml files enclosed in the Orphanet nomenclature pack for coding). More information about the Aggregation level can be found here.
• Recommendations and helpdesk for coding are available below in the dropdown menu.
• In addition, a human-readable mapping file ORPHAcodes-SNOMED CT is provided at the bottom of this page.

The last yearly version of the nomenclature is also available through dedicated API and a human-readable view is provided through Dataviz, a  classifications browser as well as a  mappings browser.

N.B. The previous versions as well as the related change logs remain accessible and downloadable in this GitHub.

A SNOMED CT-Orphanet nomenclature map has been produced in XLSX format in English. The product of a joint project carried out under a collaboration agreement between the Institut national de la santé et de la recherche médicale (INSERM) and SNOMED International.

Based on an agreed priority set, new concepts for rare diseases as defined in Orphanet have been added to SNOMED CT and a map from SNOMED CT to the Orphanet Nomenclature of Rare Diseases has been created.

Access to the human readable map is made available from Orphanet below, and the RF2 version is available from SNOMED International for Members and Affiliates from the organization’s Member Licensing and Distribution Service.

Release of October 2024

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It is the responsibility of those implementing this product to ensure that they are appropriately licensed and for more information on the license, including how to register as an Affiliate Licensee, please refer to :

• http://www.snomed.org/snomed-ct/get-snomed-ct 
• info@snomed.org.

Under the terms of the Affiliate License, use of SNOMED CT in countries that are not IHTSDO Members is subject to reporting and fee payment obligations.