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UMLS API Technical Documentation

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Retrieving UMLS Atom Ancestors and Descendants

URIs | Query Parameters | Sample Output

URIs with /ancestors or /descendants support the following use cases:

  • Retrieve all ancestors of a known UMLS atom.
  • Retrieve all descendants of a known UMLS atom.

Note that ‘current’ in the URI can always be used to search against the latest UMLS publication.
You may use any valid UMLS release back to 2008AA in your URI if you would like to search against a particular version of the UMLS.


The base URI is https://uts-ws.nlm.nih.gov/rest

Sample URI Description Returned JSON Object classType
/content/current/AUI/A10134087/ancestors Retrieves ancestors of a UMLS atom Atom
/content/current/AUI/A10134087/descendants Retrieves descendants of a UMLS atom Atom

Query Parameters

Parameter name Required? Y/N Description Valid Values Default value Usage Note
ticket Y A single-use service ticket is required for each call to the API. See authentication for more information n/a n/a n/a
pageNumber N Whole number that specifies which page of results to fetch. 1,2,3, etc 1 n/a
pageSize N Whole number that specifies the number of results to include per page. 1,2,3, etc 25 n/a

Sample Output

Sample output for https://uts-ws.nlm.nih.gov/rest/content/current/AUI/A10134087/descendants?ticket=ST…

	"pageSize" : 25,
	"pageNumber" : 1,
	"pageCount" : 15,
	"result" : [{
			"classType" : "Atom",
			"ui" : "A10133773",
			"suppressible" : "false",
			"obsolete" : "false",
			"rootSource" : "HL7V3.0",
			"termType" : "PT",
			"code" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/HL7V3.0/_IntrabursalRoute",
			"concept" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/CUI/C1522205",
			"sourceConcept" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/HL7V3.0/21172",
			"sourceDescriptor" : "NONE",
			"attributes" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133773/attributes",
			"parents" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133773/parents",
			"ancestors" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133773/ancestors",
			"children" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133773/children",
			"descendants" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133773/descendants",
			"relations" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133773/relations",
			"name" : "IntrabursalRoute",
			"language" : "ENG",
			"contentViewMemberships" : []
		}, {
			"classType" : "Atom",
			"ui" : "A8317632",
			"suppressible" : "false",
			"obsolete" : "false",
			"rootSource" : "HL7V3.0",
			"termType" : "PT",
			"code" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/HL7V3.0/IBURSINJ",
			"concept" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/CUI/C0848586",
			"sourceConcept" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/HL7V3.0/14643",
			"sourceDescriptor" : "NONE",
			"attributes" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A8317632/attributes",
			"parents" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A8317632/parents",
			"ancestors" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A8317632/ancestors",
			"children" : "NONE",
			"descendants" : null,
			"relations" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A8317632/relations",
			"name" : "Injection, intrabursal",
			"language" : "ENG",
			"contentViewMemberships" : []
		}, {
			"classType" : "Atom",
			"ui" : "A10133791",
			"suppressible" : "false",
			"obsolete" : "false",
			"rootSource" : "HL7V3.0",
			"termType" : "PT",
			"code" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/HL7V3.0/_IntraepidermalRoute",
			"concept" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/CUI/C1512941",
			"sourceConcept" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/HL7V3.0/21190",
			"sourceDescriptor" : "NONE",
			"attributes" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133791/attributes",
			"parents" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133791/parents",
			"ancestors" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133791/ancestors",
			"children" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133791/children",
			"descendants" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133791/descendants",
			"relations" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/AUI/A10133791/relations",
			"name" : "IntraepidermalRoute",
			"language" : "ENG",
			"contentViewMemberships" : []