--- a/src/pyams_content_es/component/theme.py	Mon Jun 11 12:42:04 2018 +0200
+++ b/src/pyams_content_es/component/theme.py	Mon Jun 11 12:43:02 2018 +0200
@@ -19,11 +19,13 @@
 from pyams_content.component.theme.interfaces import IThemesTarget, IThemesInfo
 from pyams_content.shared.view.interfaces import IWfView, IViewQueryEsParamsExtension, IViewThemesSettings
 from pyams_content_es.interfaces import IDocumentIndexInfo
+from zope.intid.interfaces import IIntIds
 
 # import packages
 from elasticsearch_dsl import Q
 from pyams_utils.adapter import adapter_config, ContextAdapter
 from pyams_utils.list import unique
+from pyams_utils.registry import get_utility
 
 
 @adapter_config(name='themes', context=IThemesTarget, provides=IDocumentIndexInfo)
@@ -33,17 +35,22 @@
     parents = []
     synonyms = []
     associations = []
+    intids = get_utility(IIntIds)
     for term in IThemesInfo(content).themes or ():
-        terms.append(term.label)
+        terms.append(term)
         if term.usage is not None:
-            terms.append(term.usage.label)
-        parents.extend([parent.label for parent in term.get_parents()])
-        synonyms.extend([synonym.label for synonym in term.used_for])
-        associations.extend([association.label for association in term.associations])
-    return {'themes': {'terms': unique(terms),
-                       'parents': unique(parents),
-                       'synonyms': unique(synonyms),
-                       'associations': unique(associations)}}
+            terms.append(term.usage)
+        parents.extend(term.get_parents())
+        synonyms.extend(term.used_for)
+        associations.extend(term.associations)
+    return {
+        'themes': {
+            'terms': [intids.register(term) for term in unique(terms)],
+            'parents': [intids.register(term) for term in unique(parents)],
+            'synonyms': [intids.register(term) for term in unique(synonyms)],
+            'associations': [intids.register(term) for term in unique(associations)]
+        }
+    }
 
 
 @adapter_config(name='themes', context=IWfView, provides=IViewQueryEsParamsExtension)