diff --git a/src/server/ch/epfl/lca1/medco/util/Constants.java b/src/server/ch/epfl/lca1/medco/util/Constants.java
index d9db43c..6a9eb8f 100644
--- a/src/server/ch/epfl/lca1/medco/util/Constants.java
+++ b/src/server/ch/epfl/lca1/medco/util/Constants.java
@@ -1,67 +1,67 @@
 package ch.epfl.lca1.medco.util;
 
 import java.util.regex.Pattern;
 
 public class Constants {
 
     // -----------------------------------------------------
     // XML formats -----------------------------------------
     // -----------------------------------------------------
 
     public static String
             DDT_REQ_XML_EL = "unlynx_ddt_request",
             DDT_REQ_XML_START_TAG = "<" + DDT_REQ_XML_EL + ">",
             DDT_REQ_XML_END_TAG = "</" + DDT_REQ_XML_EL + ">",
             DDT_RESP_XML_EL = "unlynx_ddt_response",
             DDT_RESP_XML_START_TAG = "<" + DDT_RESP_XML_EL + ">",
             DDT_RESP_XML_END_TAG = "</" + DDT_RESP_XML_EL + ">";
 
     public static String
             AGG_REQ_XML_EL = "unlynx_agg_request",
             AGG_REQ_XML_START_TAG = "<" + AGG_REQ_XML_EL + ">",
             AGG_REQ_XML_END_TAG = "</" + AGG_REQ_XML_EL + ">",
             AGG_RESP_XML_EL = "unlynx_agg_response",
             AGG_RESP_XML_START_TAG = "<" + AGG_RESP_XML_EL + ">",
             AGG_RESP_XML_END_TAG = "</" + AGG_RESP_XML_EL + ">";
 
 
     // -----------------------------------------------------
     // DB formats ------------------------------------------
     // -----------------------------------------------------
 
     public static String PATIENT_DUMMY_FLAG_COL_NAME = "enc_dummy_flag_cd";
 
 
     // -----------------------------------------------------
     // Ontology formats ------------------------------------
     // -----------------------------------------------------
 
 
     public static String
             CONCEPT_KEY_ENCRYPTED_FLAG = "ENCRYPTED_KEY",
             CONCEPT_PATH_TAGGED_PREFIX = "\\\\SENSITIVE_TAGGED\\medco\\tagged\\", // todo: should be configurable
             CONCEPT_NAME_TEST_FLAG = "TESTKEY";
 
     /**
      * Regex patterns that matches query keys with encrypted term
      * todo: replace path encrypted / tagged
      */
     public static final Pattern REGEX_QUERY_KEY_ENC =
-            Pattern.compile("^\\s*\\\\\\\\" + CONCEPT_KEY_ENCRYPTED_FLAG + "\\\\([a-zA-Z0-9+/=]+)\\\\\\s*$");
+            Pattern.compile("^\\s*\\\\\\\\" + CONCEPT_KEY_ENCRYPTED_FLAG + "\\\\([a-zA-Z0-9+/=]+)(\\\\)?\\s*$");
 
 
     /**
      * Prefixes to the MedCo concept codes.
      * <p>
      * QUERY_ITEM_KEY_ENC_PREFIX: collectively encrypted (or to be) codes
      * QUERY_ITEM_KEY_CLEAR_PREFIX: clear-text codes
      * QUERY_ITEM_KEY_TAG_PREFIX: tagged codes
      */
     public static final String
             PREFIX_QUERY_ITEM_KEY_ENC = "C_ENC:",
             PREFIX_QUERY_ITEM_KEY_TAG = "TAG:",
             PREFIX_QUERY_ITEM_KEY_CLEAR = "CLEAR:";
 
     
 }