diff --git a/src/routes/index.js b/src/routes/index.js
index 0cd9a65d9e..da96a2757d 100644
--- a/src/routes/index.js
+++ b/src/routes/index.js
@@ -199,7 +199,7 @@ module.exports = function(app, middleware) {
 	app.use(relativePath, pluginRouter);
 	app.use(relativePath, pageRouter);
 	app.use(relativePath, authRouter);
-	
+
 	if (process.env.NODE_ENV === 'development') {
 		require('./debug')(app, middleware, controllers);
 	}
diff --git a/src/topics.js b/src/topics.js
index 8aa69d268b..24535805e3 100644
--- a/src/topics.js
+++ b/src/topics.js
@@ -176,7 +176,7 @@ var async = require('async'),
 				return array.map(function(topic) {
 					return topic && topic[field];
 				}).filter(function(value, index, array) {
-					return value && array.indexOf(value) === index;
+					return utils.isNumber(value) && array.indexOf(value) === index;
 				});
 			}
 
diff --git a/src/user.js b/src/user.js
index ad2d5852f9..6cd8a125ea 100644
--- a/src/user.js
+++ b/src/user.js
@@ -109,6 +109,7 @@ var	async = require('async'),
 			}
 
 			if (!parseInt(user.uid, 10)) {
+				user.uid = 0;
 				user.username = '[[global:guest]]';
 				user.userslug = '';
 			}