Is lupus a cause for permanent disability?!

Hi, after many breakouts/crisis related to lupus, a friend of mine was finally laid out from her job. She now is clinging on to the hope to be declared permanent disabled to then get entitled to pension/early retirement benefits. I am just not sure that lupus classifies as cause of permanent dissability. Is it? Have you or anyone you know affected by this condition been declared disabled and entitled to retirement because of lupus?