Getting massive number of database errors on sitemeta

I am getting a huge number of the same database error which is resulting in memory problems which is greatly impacting my server. Here it is:

[11-Mar-2014 12:15:56 UTC] WordPress database error Duplicate entry '4051' for key 'PRIMARY' for query INSERT INTO'ht_sitemeta'('site_id','meta_key','meta_value') VALUES (1,'_site_transient_timeout_theme_roots','1394541956') made by do_action_ref_array, call_user_func_array, wp_update_themes, wp_get_themes, search_theme_directories, set_site_transient, add_site_option, m_wpdb->query

Any thoughts on this?