What is an autoimmune disease.?how could it be diagnosed.?

Body attacks self: Rheumatoid arthritis and lupus are examples where the body attacks itself.The diagnosis is complicated requiring an expert ( typically a rheumatologist ) abd requires extensive lab work.

An autoimmune : Disease is one that is caused by the immune system reacting against the patient themselves. It is hard to be more speicific, as this can affect a large number of different tissues or organs. There would not be "one" way to diagnose.

Autoimmune diseases : In auto immune disease the enemy is from with in . One 's own immune system for unknown reason turns against self and destroys or damages tissues , cells and targeted organs. Diagnosis depends upon which tissue , cell or organ is affected . Diagnosis is made on clinical picture with immunological studies targeted to cell, tissue organ involved and at times biopsy of affected tissues and organ.