الفهرس 
Overview of Alopecia Areata
Neopterin and Neurodegenerative Diseases:Only 14 pages are availabe for public view
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Abstract
Alopecia areata is a chronic inflammatory condition causing nonscarring hair loss. It may be patchy, involve the entire scalp (AT) or whole body (AU).
Although several hypotheses have been proposed, the exact pathogenesis of hair loss is not clear. Among the many factors which appear to be implicated are the patient’s genetic constitution, nonspecific immune and anagen-specific autoimmune reactions and possibly emotional stress.
Most evidence supports the hypothesis that AA is T-cell mediated autoimmune disease and their cytokines and chemokine play an important role. The immune response present in AA is associated with aberrant lesional expression of IFN-, IL-2 and IL-1 and over expression of ICAM-1 and MHC molecules on hair follicle keratinocytes and dermal papilla cells. NP is a pyrazino-pyrimidine compound derived from GTP and is produced by human monocytes and macrophages upon stimulation by IFN-γ released from activated T-cells. Significant elevation of serum NP level in patients with AA may reflect activation of (T cell mediated) immuno-pathogenic mechanisms of AA.
Phototherapies such as PUVA or NB-UVB therapy have become one of the most commonly used modalities for the treatment of a variety of skin diseases. PUVA is an immuno-suppressant treatment that may be effective in AA especially with extensive scalp and body hair loss. NB-UVB has the same immunosuppressive action as PUVA and is used in the treatment of many autoimmune diseases as psoriasis and vitiligo; also few studies reported use of NB-UVB in AA.
This work was performed to compare the effect of NB-UVB and PUVA on serum level of NP as a marker of T-cell activation in patients with AA before and after treatment.
This study included 60 subjects: 30 patients with AA were divided into 3 equally distributed groups: 10 patients subjected to treatment by topical PUVA (group 1), 10 patients subjected to treatment by systemic PUVA (group 2) and 10 patients subjected to treatment by NB-UVB (group 3) and 30 age and sex matched healthy controls.
Each patient was subjected to a detailed history taking and examination to detect type, extent (SALT score) of AA. Blood samples were taken from all subjects to assess serum level of NP by ELISA technique that probably reflects activation of T cell-mediated immuno-pathogenic mechanisms. Correlation between the serum concentration of NP and the SALT score measurement of disease activity was done. We also determined the effects of PUVA and NB-UVB on the following indices of disease activity, serum NP levels and SALT scores in patients with AA.
The obtained data are tabulated and subjected to statistical analysis using different tests of significance.
In our study, patients with AA were found to have elevated levels of pretreatment and posttreatment serum NP in comparison to controls with significant reduction of mean serum NP levels and SALT scores after topical PUVA, systemic PUVA and NB-UVB. No significant difference in mean serum NP levels and SALT scores between the three groups of patients before and after treatment. However, serum NP levels and SALT scores for patients receiving either topical or systemic PUVA (Groups 1 and 2) were lower than in those receiving NB-UVB (Group 3) after 3 months of treatment. This difference was not statistically significant indicating that both lines of treatment are comparable. There was significant correlation between serum NP levels and SALT scores among three groups of patients with AA before and after treatment. There was no significant correlation between pretreatment serum NP levels and duration of disease in patients with AA.