Psoriasis
Psoriasis is a long-lasting autoimmune disease characterized by patches of abnormal skin.[6] These skin patches are typically red, dry, itchy, 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, guttate, inverse, pustular, 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 studies, identical 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 creams, vitamin 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 arthritis, lymphomas, cardiovascular disease, Crohn’s disease and depression.[4] Psoriatic arthritis affects up to 30 percent of individuals with psoriasis.[11]
San Diego
San Diego (/ˌsæn diːˈeɪɡoʊ/, Spanish for “Saint Didacus“; Spanish: [san ˈdje.ɣo]) is a major city in California, United States. It is in San Diego County, on the coast of the Pacific Ocean in Southern California, approximately 120 miles (190 km) south of Los Angeles and immediately adjacent to the border with Mexico.
With an estimated population of 1,394,928 as of July 1, 2015,[9] San Diego is the eighth-largest city in the United States andsecond-largest in California. It is part of the San Diego–Tijuana conurbation, the second-largest transborder agglomerationbetween the US and a bordering country after Detroit–Windsor, with a population of 4,922,723 people.[11] San Diego has been called “the birthplace of California”.[12] It is known for its mild year-round climate, natural deep-water harbor, extensive beaches, long association with the United States Navy, and recent emergence as a healthcare and biotechnology development center.
Historically home to the Kumeyaay people, San Diego was the first site visited by Europeans on what is now the West Coast of the United States. Upon landing in San Diego Bay in 1542, Juan Rodríguez Cabrillo claimed the area for Spain, forming the basis for the settlement of Alta California 200 years later. The Presidio and Mission San Diego de Alcalá, founded in 1769, formed the first European settlement in what is now California. In 1821, San Diego became part of the newly independent Mexico, which reformed as the First Mexican Republic two years later. In 1850, California became part of the United States following the Mexican–American War and the admission of California to the union.
The city is the seat of San Diego County and is the economic center of the region as well as the San Diego–Tijuanametropolitan area. San Diego’s main economic engines are military and defense-related activities, tourism, international trade, and manufacturing. The presence of the University of California, San Diego (UCSD), with the affiliated UCSD Medical Center, has helped make the area a center of research in biotechnology.