Affects about 5 percent of people with psoriasis, a chronic skin disease. Likely to affect fingers or spine. Symptoms are mild in most people but can be quite severe. Affects about 160,000 Americans. Systemic Lupus Erythematosus Involves skin, joints, muscles, and sometimes internal organs.
Symptoms usually appear in women of childbearing age but can occur in anyone at any age.
Also called lupus or SLE, it can be mild or life threatening. Affects at least 131,000 Americans, nine to ten times as many women as men. Other forms Arthritis can develop as a result of an infection. For example, bacteria that cause gonorrhea or Lyme disease can cause arthritis. Infectious arthritis can cause serious damage, but usually clears up completely with antibiotics.