Share +. Text A A A. Rheumatoid arthritis (RA) is an autoimmune disease where the body's immune system attacks normal joint tissues, causing inflammation of the joint lining. This inflammation of the joint lining (called the synovium) can cause pain, stiffness, swelling, warmth, and redness.ext A A A. Rheumatoid arthritis (RA) is an autoimmune disease where the body's immune system attacks normal joint tissues, causing inflammation of the joint lining.
Tuberculosis. Tuberculosis (TB) is an infectious disease caused by a bacterium that usually attacks the lungs. TB is spread through the air from one person to another. The bacteria are put into the air when a person with active TB disease of the lungs or throat coughs, sneezes, speaks, or sings.
1 Tuberculosis is only infectious if the disease is in the lungs (pulmonary TB) and the person is coughing the germ into the air. 2  People then breathe the germ into their lungs and become infected. 3  It usually requires close, prolonged contact with the case to get the TB germ.