It appears that you have developed an autoimmune arthritis. An autoimmune condition is one where your own body defenses (white blood cells and antibodies) have mistakenly identified some of your own host tissues as “foreign invaders”. In your case, the proteins that appear “foreign” to your immune system are in the joints of your body.
You mention two separate conditions, rheumatic fever and rheumatoid arthritis. These are different problems but can lead to similar symptoms. Rheumatic fever starts with a strep infection in your throat (sore throat) and is found in younger individuals (10-20 years of age normally). In your case, this infecting bacteria has very similar proteins as some of the tissues of your body. Your body has mistakenly confused your own joint proteins as part of this streptococcus bacterial infection. Your body then goes forward attacking these proteins as it thinks that certain cells in your joints are this bacteria. The heart, brain and skin can also be involved. The joint inflammation is not normally destructive.
Rheumatoid arthritis has a similar mode of pathology but is a different disease process.
Dr. Corenman
Donald Corenman, MD, DC is a highly-regarded spine surgeon, considered an expert in the area of neck and back pain. Trained as both a Medical Doctor and Doctor of Chiropractic, Dr. Corenman earned academic appointments as Clinical Assistant Professor and Assistant Professor of Orthopaedic Surgery at the University of Colorado Health Sciences Center, and his research on spine surgery and rehabilitation has resulted in the publication of multiple peer-reviewed articles and two books.