diff --git a/src/phi/ldap/client.py b/src/phi/ldap/client.py
index 17cd169..1c1e449 100644
--- a/src/phi/ldap/client.py
+++ b/src/phi/ldap/client.py
@@ -14,8 +14,7 @@ class Client:
                  host=None, port=389,
                  encryption=None, ciphers=None, validate=False, ca_certs=None,
                  username=None, password=None,
-                 base_dn=None,
-                 attribute_id='uid', attribute_mail='mail'):
+                 base_dn=None):
         log.info("Initializing LDAP Client.")
 
         self.host = host
@@ -31,9 +30,6 @@ class Client:
 
         self.base_dn = base_dn
 
-        self.attribute_id = attribute_id
-        self.attribute_mail = attribute_mail
-
         self.connection_lock = Lock()
         self.connection = make_connection(host=self.host, port=self.port,
                                           encryption=self.encryption,
diff --git a/src/phi/ldap/entry.py b/src/phi/ldap/entry.py
index c9e9a2c..27ec5a2 100644
--- a/src/phi/ldap/entry.py
+++ b/src/phi/ldap/entry.py
@@ -8,7 +8,7 @@ log = get_logger(__name__)
 def get_entry_by_uid(client, uid):
     log.info("Searching entry with identifier: {}".format(uid))
 
-    filter_ = "({}={})".format(client.attribute_id, uid)
+    filter_ = "({}={})".format('uid', uid)
     log.debug("Search filter: {}".format(filter_))
 
     response_id = client.connection.search(
diff --git a/src/phi/ldap/user.py b/src/phi/ldap/user.py
index 29e2e5a..1ab3642 100644
--- a/src/phi/ldap/user.py
+++ b/src/phi/ldap/user.py
@@ -1,26 +1,22 @@
 from phi.ldap.entry import get_entry_by_uid
-from phi.ldap.utils import flatten_attributes
-
-
-def user_attributes_mapping(client):
-    return {
-        client.attribute_id: 'uid',
-        client.attribute_mail: 'mail',
-        'createTimestamp': 'created_at',
-        'modifyTimestamp': 'modified_at'
-    }
 
 
 def get_user_by_uid(client, uid):
+    shown_keys = ['uid', 'mail', 'createTimestamp', 'modifyTimestamp']
+
     entry = get_entry_by_uid(client, uid)
 
     if not entry:
         return None
 
-    mapping = user_attributes_mapping(client)
+    def flatten(attr):
+        if isinstance(attr, list) and len(attr)==1:
+            return attr[0]
+        else:
+            return attr
 
-    user = {mapping[k]: v
-            for k, v in entry['attributes'].items()
-            if k in mapping.keys()}
+    user = {k: flatten(attr)
+            for k, attr in entry['attributes'].items()
+            if k in shown_keys}
 
-    return flatten_attributes(user)
+    return user
diff --git a/src/phi/ldap/utils.py b/src/phi/ldap/utils.py
deleted file mode 100644
index a44ab92..0000000
--- a/src/phi/ldap/utils.py
+++ /dev/null
@@ -1,3 +0,0 @@
-def flatten_attributes(d):
-    return {k: (v[0] if isinstance(v, list) else v)
-            for k, v in d.items()}
diff --git a/test/conftest.py b/test/conftest.py
index 4b0e168..bf569b6 100644
--- a/test/conftest.py
+++ b/test/conftest.py
@@ -11,8 +11,7 @@ def ldap_client():
         validate=False,
         username='uid=phi,ou=Services,dc=unit,dc=macaomilano,dc=org',
         password='phi',
-        base_dn='dc=unit,dc=macaomilano,dc=org',
-        attribute_id='uid', attribute_mail='mail')
+        base_dn='dc=unit,dc=macaomilano,dc=org')
     client.open()
     yield client
     client.close()