Psoriatic arthritis of psoriatic arthritis include the following: Other symptoms that are more typical of psoriatic arthritis than other forms of arthritis include enthesitis (inflammation in the Achilles tendon (at the back of the heel) or the plantar fascia (bottom of the feet)), and dactylitis (sausage-like swelling of the fingers or toes). Several conditions can mimic the clinical presentation of psoriatic arthritis including rheumatoid arthritis, osteoarthritis, reactive arthritis, gouty arthritis, systemic lupus erythematosus, and inflammatory bowel disease-associated arthritis. In contrast to psoriatic arthritis, rheumatoid arthritis tends to affect the proximal joints (e.g., the metacarpophalangeal joints), involves a greater number of joints than
Psoriatic arthritis as a type of seronegative spondyloarthropathy. Genetics are thought to be strongly involved in the development of psoriatic arthritis. Obesity and certain forms of psoriasis are thought to increase the risk. Psoriatic arthritis affects up to 30% of people with psoriasis and occurs in both children and adults. Approximately 40–50% of individuals with psoriatic arthritis have the HLA-B27 genotype. The condition is less common in people of Asian or African descent and affects men and women equally. Pain, swelling, or stiffness in one or more joints is commonly present in psoriatic arthritis. Psoriatic arthritis is inflammatory, and affected joints are