The issue of getting an autoimmune disease through a transfusion is not settled medically I believe. Below is a link to a discussion on the subject. Lupus is normally caused by multiple factors....a set of genes that predisposes your immune system to a misdirection to attack your own body and some type of environmental trigger that causes a particular autoimmune response. In most individual cases it is not possible to determine exactly what causes lupus or another autoimmune disease. Many patients grasp at events or simple answers that just are not right or could never be connected scientifically to the disease. The other thing is that it could be multiple triggers...not just one. And they could occur over years eventually pushing your immune system over the edge.
One of the interesting things is that IVig which is a blood product from 000s of patients is often the treatment of last resort for autoimmune patients. It is thought that the reason it works is because it injects antibodies into the patient which somehow reset or normalize the immune system. It was the treatment that saved my life 10 years ago.
If I needed a blood transfusion or IVig again I would do it without hesitation. Lupus and other AI diseases remain a mystery that will be unraveled someday in the distant future.
MCTD (SLE Lupus, polymyositis, scleroderma). Diagnosed 2005. Kidney, liver, GI tract, dysphagia, raynauds, barretts esophagus, quadriplegic in 2005. Recovered and now active in downhill skiing, golf, hiking. Meds: amlodipine, benezapril, omeprazole, potassium, folic acid, vitamins, maxide.
Remain Optimistic and you can overcome.