diff --git a/arkindex/documents/api/elements.py b/arkindex/documents/api/elements.py
index 0538463f91d71cd110e6033e4968bc28b681d11a..c80f734a43cc899cc7a01c50ef11b42e6096ac6c 100644
--- a/arkindex/documents/api/elements.py
+++ b/arkindex/documents/api/elements.py
@@ -149,7 +149,7 @@ class ElementsList(CorpusACLMixin, ListAPIView):
         if structure_param is not None:
             filters['metadatas__in'] = MetaData.objects.filter(
                 type=MetaType.Structure,
-                value__contains=structure_param
+                value__icontains=structure_param
             )
 
         if 'corpus' in self.request.query_params:
@@ -421,7 +421,7 @@ class ElementParents(ListAPIView):
         if structure_param is not None:
             filters['metadatas__in'] = MetaData.objects.filter(
                 type=MetaType.Structure,
-                value__contains=structure_param
+                value__icontains=structure_param
             )
 
         recursive_param = self.request.query_params.get('recursive')
@@ -573,7 +573,7 @@ class ElementChildren(ListAPIView):
         if structure_param is not None:
             filters['metadatas__in'] = MetaData.objects.filter(
                 type=MetaType.Structure,
-                value__contains=structure_param
+                value__icontains=structure_param
             )
 
         recursive_param = self.request.query_params.get('recursive')