<unk>  is a long-term inflammatory arthritis that occurs in people affected by the autoimmune disease psoriasis. The classic feature of<unk>  is swelling of entire fingers and toes with a sausage-like appearance. This often happens in association with changes to the nails such as small depressions in the nail (pitting), thickening of the nails, and detachment of the nail from the nailbed. Skin changes consistent with psoriasis (e.g., red, scaly, and itchy plaques) frequently occur before the onset of<unk>  but<unk>  can precede the rash in 15% of affected individuals. It is classified as a type of seronegative spondyloarthropathy. Genetics are thought to be strongly involved in the development of<unk> . Obesity and certain forms of psoriasis are thought to increase the risk.<unk>  affects up to 30% of people with psoriasis and occurs in both children and adults. Approximately 40–50% of individuals with<unk>  have the HLA-B27 genotype. The condition is less common in people of Asian or African descent and affects men and women equally.
Psoriatic arthritis
Rheumatoid arthritis
Reactive arthritis
Inflammatory arthritis
Juvenile idiopathic arthritis
Post-traumatic arthritis
Enteropathic arthropathy
Oligoarthritis