الفهرس 
PSORIASISOnly 14 pages are availabe for public view
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Abstract
soriasis is a common chronic, immune-mediated skin disease with many provocative factors, clinically characterized by red, scaly, small to large plaques of diseased skin covered with silvery white scales, commonly affecting the scalp, trunk, elbows, knees and genital areas but can affect any part of the body including nails.
Understanding the pathogenesis events leading to psoriasis has improved significantly lately. It is well established that interplay of environmental, genetic and immunological mechanisms is associated with the development of the disease.
Psoriasis is a T –cell mediated inflammatory process with the production of free oxygen radicals, leading to the activation of tumor necrosis factor alpha (TNF-α) in psoriatic plaques, TNF-α is a cytokine that plays a crucial role in the pathogenesis of psoriasis
In psoriasis an impaired antioxidant barrier in skin results in a rise of free reactive oxygen species. Oxidative stress and the generation of excessive free radicals have been related to skin inflammation in psoriasis. These Oxygen Species show its harmful effects mostly on the cell parts, including the DNA, membrane lipids and proteins.
Selenium is an essential trace element, which among other trace elements has anti-oxidant, immune-modulating and anti-proliferative properties. Anti-oxidant and immune modulating actions through a change in the expression of cytokines and respective receptors by inhibition of mRNA for these cytokines in human keratinocytes or by making immune cells more resistant to the oxidative stress, so it can act as an inhibitor of oxidative stress and inflammation.
As such, selenium compounds (inorganic selenium salts) induce inhibitory effects on inflammatory cytokine production: interleukin-1α, interleukin-6, and tumor necrosis factor alpha (TNF-α) in vitro. Selenium has also a particularly strong influence on the activation, proliferation, and differentiation of naive T cells during the initiation of immune responses.
So, the aim in this study was to use the level of selenium scalp hair as a tool for the evaluation the level of the body selenium, one of the anti- oxidants in psoriasis as an inflammatory disease, characterized by production of ROS.
Twenty patients diagnosed clinically with psoriasis were enrolled in our study. All patients were subjected to full history taking, full clinical and dermatological examination and assessment of the degree of severity using PASI score. Twenty healthy age and sex matched individuals were studied as the control.
Scalp hair samples weighing approximately 1.0g taken from the occipital region of the head of patients and controls with stainless steel scissors and stored plastic bags. The mineral element Se will measure by inductively coupled plasma mass spectrometry (ICP_MS).
The level of selenium (ng/gm) was then correlated with age gender, family history, medical history, age of onset of psoriasis, duration, course of the disease, and severity of psoriasis.
As regard the patients group, the age of onset of the disease ranged between 13 and 40 years (mean±SD 24.5±6), the duration of the disease ranged from 5 to 25 yrs (mean±SD13.8±6.3), the course of diseases was progressive in 17(85%) patients and stable in 3(15%), the selenium level (ng/gm) ranged between (182.2-311.7ng/gm) (mean±SD274.1±32). PASI score ranged (5.1-20.2) (mean±SD10.9±5.1).
There was a highly statistically significant difference between patients and controls as regard selenium level (274.1±32.0, 354.7±38.1
P <0.001, respectively), with significant negative correlation between Se. Level (ng/gm) and PASI (P=0.002, r= -0.638) was found.
There was no statistically significant differences between selenium levels as regard sex between female and male (mean±SD, 280.33±19.89, 264.79±44.56, P=.0299, t=-1.069, respectively).
There was neither significant correlation found between the onset of the disease and selenium level (P=0.249, r=0.270), nor between the duration of the disease and Selenium level (ng/gm), (p =0.263, r= -0.263).
No statistically significant difference was found between the patients with positive family history versus the patients with negative family history (262.41, ±37.20, 277.04 ± 31.17, P= 0.428, t -.811, respectively).
No statistically significant difference in scalp selenium level with progressive course of disease versus stable course (271.41±33.39, 289.45±19.32, p=0.382, t= -0.897, respectively).
Information on selenium in psoriasis is scarce. It was found that serum selenium level in psoriasis patients is lower than that of healthy individuals, but there are few studies on its role in the pathogenesis of the disease. Disturbances in keratinization, leading to excessive loss of trace elements with desquamation, malabsorption, or tissue distribution abnormalities and insufficient dietary intake of selenium in psoriasis patients were suggested as explanations of this phenomenon.
The study showed that the discrimination of the severity of psoriasis by using the level of the scalp hair selenium(ng/mg) as diagnostic tool can be reliable with 100% sensitivity, 95% specificity and 98.3% dignostic accuracy
Taken together, our findings indicated the possibility of assessingselenium in scalp hair. Lower selenium level was evident in psoriasis vulgaris patients. Lower selenium level correlated negatively with disease severity, whichpointed to the role and the influence of selenium on psoriasis pathogenesis and severity.