How common ice lupus misdiagnosed for sarcoidosis?

Labs,imaging, biopsy: Lupus and sarcoidosis affects many organs and both can have similar symptoms.However doctor(rheumatologist) can differentiate these two diseases by various blood tests, imaging and sometimes biopsy - skin, liver and kidney depending on the organ involved.So the diagnosis is often clear, raraly misdiagnosed. The diagnosis must be confirmed as the treatment options are quite different.