diff --git a/src/categories/unread.js b/src/categories/unread.js
index 99c944b194..d62aaa3c6e 100644
--- a/src/categories/unread.js
+++ b/src/categories/unread.js
@@ -34,9 +34,7 @@ module.exports = function(Categories) {
 
 	Categories.markAsUnreadForAll = function(cid, callback) {
 		callback = callback || function() {};
-		db.delete('cid:' + cid + ':read_by_uid', function(err) {
-			callback(err);
-		});
+		db.delete('cid:' + cid + ':read_by_uid', callback);
 	};
 
 	Categories.hasReadCategories = function(cids, uid, callback) {
diff --git a/src/categories/update.js b/src/categories/update.js
index f1cf7c02af..e103d3e5dc 100644
--- a/src/categories/update.js
+++ b/src/categories/update.js
@@ -19,23 +19,6 @@ module.exports = function(Categories) {
 			}, next);
 		}
 
-		function updateCategoryField(cid, key, value, next) {
-			db.setObjectField('category:' + cid, key, value, function(err) {
-				if(err) {
-					return next(err);
-				}
-
-				if (key === 'name') {
-					var slug = cid + '/' + utils.slugify(value);
-					db.setObjectField('category:' + cid, 'slug', slug, next);
-				} else if (key === 'order') {
-					db.sortedSetAdd('categories:cid', value, cid, next);
-				} else {
-					next();
-				}
-			});
-		}
-
 		var cids = Object.keys(modified);
 
 		async.each(cids, updateCategory, function(err) {
@@ -43,4 +26,21 @@ module.exports = function(Categories) {
 		});
 	};
 
+	function updateCategoryField(cid, key, value, callback) {
+		db.setObjectField('category:' + cid, key, value, function(err) {
+			if (err) {
+				return callback(err);
+			}
+
+			if (key === 'name') {
+				var slug = cid + '/' + utils.slugify(value);
+				db.setObjectField('category:' + cid, 'slug', slug, callback);
+			} else if (key === 'order') {
+				db.sortedSetAdd('categories:cid', value, cid, callback);
+			} else {
+				callback();
+			}
+		});
+	}
+
 };
diff --git a/src/database/mongo/main.js b/src/database/mongo/main.js
index 4611ac7e11..0e6e471476 100644
--- a/src/database/mongo/main.js
+++ b/src/database/mongo/main.js
@@ -81,7 +81,9 @@ module.exports = function(db, module) {
 		if (!key) {
 			return callback();
 		}
-		db.collection('objects').remove({_key: key}, callback);
+		db.collection('objects').remove({_key: key}, function(err, res) {
+			callback(err);
+		});
 	};
 
 	module.deleteAll = function(keys, callback) {
diff --git a/src/database/redis/main.js b/src/database/redis/main.js
index 986c3a7bc8..e021a5e82c 100644
--- a/src/database/redis/main.js
+++ b/src/database/redis/main.js
@@ -70,7 +70,9 @@ module.exports = function(redisClient, module) {
 	};
 
 	module.delete = function(key, callback) {
-		redisClient.del(key, callback);
+		redisClient.del(key, function(err, res) {
+			callback(err);
+		});
 	};
 
 	module.deleteAll = function(keys, callback) {