A. Type 1 diabetes: The pancreas produces the hormone insulin, which helps regulate blood sugar levels. In type 1 diabetes, the immune system attacks and destroys insulin-producing cells in the pancreas. High blood sugar can damage blood vessels, as well as organs like the heart, kidneys, eyes, and nerves.

B. Rheumatoid arthritis (RA): In rheumatoid arthritis (RA), the immune system attacks the joints. This attack causes redness, warmth, soreness, and stiffness in the joints.

C. Psoriasis/psoriatic arthritis: Skin cells normally grow and then shed when they're no longer needed. Psoriasis causes skin cells to multiply too quickly. The extra cells build up and form red, scaly patches called scales or plaques on the skin. About 30 percent of people with psoriasis also develop swelling, stiffness, and pain in their joints. This form of the disease is called psoriatic arthritis.

D. Multiple sclerosis: Multiple sclerosis (MS) damages the myelin sheath - the protective coating that surrounds nerve cells. Damage to the myelin sheath affects the transmission of messages between your brain and body. This damage can lead to symptoms like numbness, weakness, balance issues, and trouble walking. The disease comes in several forms, which progress at different rates. About 50 percent of people with MS need help walking within 15 years after getting the disease.

E. Systemic lupus erythematosus (lupus): Although doctors in the 1800s first described lupus as a skin disease because of the rash it produces, it actually affects many organs, including the joints, kidneys, brain, and heart. Joint pain, fatigue, and rashes are among the most common symptoms.