diff --git a/src/proxy.php b/src/proxy.php
index a82f614..158955d 100644
--- a/src/proxy.php
+++ b/src/proxy.php
@@ -226,7 +226,7 @@ protected function _gatherRequestInfo()
      */
     protected function _loadRoute()
     {
-        if(!key_exists('route', $_GET))
+        if(!isset($_GET['route']))
             throw new Exception("You must supply a 'route' parameter in the request");
 
         $this->_route = $_GET['route'];
@@ -256,7 +256,7 @@ protected function _loadRequestMethod()
     {
         if($this->_requestMethod !== NULL) return;
 
-        if(! key_exists('REQUEST_METHOD', $_SERVER))
+        if(! isset($_SERVER['REQUEST_METHOD']))
             throw new Exception("Request method unknown");
 
         $method = strtolower($_SERVER['REQUEST_METHOD']);
@@ -281,7 +281,7 @@ protected function _loadRequestUserAgent()
     {
         if($this->_requestUserAgent !== NULL) return;
 
-        if(! key_exists('HTTP_USER_AGENT', $_SERVER))
+        if(!isset($_SERVER['HTTP_USER_AGENT']))
             throw new Exception("No HTTP User Agent was found");
 
         $this->_requestUserAgent = $_SERVER['HTTP_USER_AGENT'];
@@ -305,7 +305,7 @@ protected function _loadContentType()
     {
         $this->_loadRawHeaders();
 
-        if(key_exists('Content-Type', $this->_rawHeaders))
+        if(isset($this->_rawHeaders['Content-Type']))
             $this->_requestContentType = $this->_rawHeaders['Content-Type'];
     }
 
@@ -336,7 +336,7 @@ protected function _checkPermissions()
         if($this->_allowedHostnames === NULL)
             return;
 
-        if(key_exists('REMOTE_HOST', $_SERVER))
+        if(isset($_SERVER['REMOTE_HOST']))
             $host = $_SERVER['REMOTE_HOST'];
         else
             $host = $_SERVER['REMOTE_ADDR'];
@@ -579,7 +579,7 @@ protected function _buildProxyRequestCookieString()
     {
         $cookie_string  = '';
 
-        if(key_exists('Cookie', $this->_rawHeaders))
+        if(isset($this->_rawHeaders['Cookie']))
             $cookie_string = $this->_rawHeaders['Cookie'];
 
         return $cookie_string;