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.
In these people, the bacteria are inactive (latent) and cannot be transmitted to others. If the body's immune system weakens, tuberculosis can become active and cause disease. Worldwide, tuberculosis is second only to the human immunodeficiency virus (HIV) in causes of death by infectious disease among adults.