Psoriasis

Abstract Psoriasis is a common inflammatory skin disease with an incompletely understood etiology. The disease is characterized by red, scaly and well-demarcated skin lesions formed by the hyperproliferation of epidermal keratinocytes. This hyperproliferation is driven by cytokines secreted by activated resident immune cells, an infiltrate of T cells, dendritic cells and cells of the innate immune system, as well as the keratinocytes themselves. Psoriasis has a strong hereditary character and has a complex genetic background. Genome-wide association studies have identified polymorphisms within or near a number of genes encoding cytokines, cytokine receptors or elements of their signal transduction pathways, further implicating these cytokines in the psoriasis path mechanism. A considerable number of inflammatory cytokines have been shown to be elevated in lesional psoriasis skin, and the serum concentrations of a subset of these also correlate with psoriasis disease severity. The combined effects of the cytokines found in psoriasis lesions likely explain most of the clinical features of psoriasis, such as the hyperproliferation of keratinocytes, increased neovascularization and skin inflammation. Thus, understanding which cytokines play a pivotal role in the disease process can suggest potential therapeutic targets. A number of cytokines have been therapeutically targeted with success, revolutionizing treatment of this disease. Here we review a number of key cytokines implicated in the pathogenesis of psoriasis.

Some autoimmune conditions have been associated with reduced vitamin D levels, has been associated with vitamin D insufficiency. Reports showed that serum 25-hydroxyvitamin D levels are inversely associated with chronic inflammatory systemic diseases. The main objective of this study was to estimate 25-hydroxyvitamin D level in patients with psoriasis in comparison with control subjects without this disease. Total of 188 (90 male and 98 female) patients with psoriasis were selected and included in the study. Eighty non-psoriatic individuals (40 male and 40 female) with different ages were included as controls.Levels of 25-OH vitamin D were determined using ELISA test kits (Euroimmun-Germany). serum concentrations of vitamin D were significantly lower in psoriatic patients than in control 19.52±10.03 pg/ml, and 40.39±9.06 pg/ml, respectively. The mean of duration of the disease was 13.08±10.5. The mean age of patient was 33.7±14.6 and of control group was 28.0±7.4. There is insignificant difference between concentrations of vitamin D in female compared to male 21.8±10.7 and 17.2±8.9, respectively, P=0.143. Insignificant correlation was found between duration of disease concentration of Vitamin D, P=0.259. The finding of this study showed that the hypovitaminosis Dwas associated with psoriasis disease in Sudan. Gender and duration of the disease were not associated with vitamin D level.