How to purge added records with doctrine fixtures

I'm using DoctrineFixturesBundle to create test records before each test is executed. But it created a mess in my database, so I want to remove those added records after each test is finished. How can I do this without removing the whole database?

   /**
     * Function initializing test environment
     */
    protected function setUp()
    {
        //
        // set the client object for easier access (and cleaner code)
        //
        $this->client = static::createClient();

        //
        // create database fixtures
        //
        $container = $this->client->getContainer();
        $doctrine = $container->get('doctrine');
        $entityManager = $doctrine->getManager();

        $userFixture = new LoadUsersData();
        $userFixture->load($entityManager);
    }

    /**
     * Function that runs when the testing is finished
     */
    public function tearDown()
    {
        parent::tearDown();

        //
        // purge database fixtures
        //


        //
        // close database connection
        //
        $this->em->close();
    }