Psoriasis is a long-lasting autoimmune disease characterized by patches of abnormal skin.[6] These skin patches are typically reddryitchy, and scaly.[3] On people with darker skin the patches may be purple in colour.[9] Psoriasis varies in severity from small, localized patches to complete body coverage.[3] Injury to the skin can trigger psoriatic skin changes at that spot, which is known as the Koebner phenomenon.[10]

There are five main types of psoriasis: plaque, guttateinversepustular, and erythrodermic.[6] Plaque psoriasis, also known as psoriasis vulgaris, makes up about 90 percent of cases.[4] It typically presents as red patches with white scales on top.[4] Areas of the body most commonly affected are the back of the forearms, shins, navel area, and scalp.[4] Guttate psoriasis has drop-shaped lesions.[6] Pustular psoriasis presents as small non-infectious pus-filled blisters.[11] Inverse psoriasis forms red patches in skin folds.[6] Erythrodermic psoriasis occurs when the rash becomes very widespread, and can develop from any of the other types.[4]Fingernails and toenails are affected in most people with psoriasis at some point in time.[4] This may include pits in the nails or changes in nail color.[4]

Psoriasis is generally thought to be a genetic disease that is triggered by environmental factors.[3] In twin studiesidentical twins are three times more likely to be affected compared to non-identical twins. This suggests that genetic factors predispose to psoriasis.[4] Symptoms often worsen during winter and with certain medications, such as beta blockers or NSAIDs.[4] Infections and psychological stress can also play a role.[3][6]Psoriasis is not contagious.[4] The underlying mechanism involves the immune system reacting to skin cells.[4] Diagnosis is typically based on the signs and symptoms.[4]

There is no cure for psoriasis; however, various treatments can help control the symptoms.[4] These treatments include steroid creamsvitamin D3 cream, ultraviolet light and immune system suppressing medications, such as methotrexate.[6] About 75 percent of cases can be managed with creams alone.[4] The disease affects two to four percent of the population.[8] Men and women are affected with equal frequency.[6] The disease may begin at any age, but typically starts in adulthood.[5] Psoriasis is associated with an increased risk of psoriatic arthritislymphomascardiovascular diseaseCrohn’s disease and depression.[4] Psoriatic arthritis affects up to 30 percent of individuals with psoriasis.[11]

Sioux Falls

Sioux Falls (/ˌs ˈfɔːlz/) (LakotaÍŋyaŋ Okábleča Otȟúŋwahe;[8] “Stone Shatter City”) is the largest city in the U.S. state of South Dakota. It is the county seat of Minnehaha County,[9] and also extends into Lincoln County to the south. It is the 47th fastest-growing city in the United States[10] and the fastest-growing metro area in South Dakota, with a population increase of 22% between 2000 and 2010.[11]

As of 2016, Sioux Falls had an estimated population of 178,500. The metropolitan population of 251,854 accounts for 29% of South Dakota’s population. It is also the primary city of the Sioux Falls-Sioux City Designated Market Area (DMA), a larger media market region that covers parts of four states and has a population of 1,043,450.[12] Chartered in 1856 on the banks of the Big Sioux River, the city is situated in the rolling hills on the western edge of the Midwest at the junction of Interstate 90 and Interstate 29.

The history of Sioux Falls revolves around the cascades of the Big Sioux River. The falls were created about 14,000 years ago during the last ice age. The lure of the falls has been a powerful influence. Ho-Chunk, Ioway, Otoe, Missouri, Omaha (and Ponca at the time), Quapaw, Kansa, Osage, Arikira, Dakota, Nakota and Cheyenne people inhabited and settled the region previous to Europeans and European descendants. Numerousburial mounds still exist on the high bluffs near the river and are spread throughout the general vicinity. Indigenous people maintained an agricultural society with fortified villages, and the later arrivals rebuilt on many of the same sites that were previously settled. Lakotapopulate urban and reservation communities in the contemporary state and many Lakota, Dakota, Nakota, and numerous other Indigenous Americans reside in Sioux Falls today.[13]