الفهرس 
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Abstract
Vitiligo is an acquired, usually asymptomatic pigmentary disorder that results in the loss of functional melanocytes and is often associated with other autoimmune diseases. At the onset of the disease white patches of different sizes appear on different parts of the body .Vitiligo affects approximately 1% of the world population of all skin types, usually before the age of 20 .Its psychological impact on the quality of life can be disastrous, as dissatisfaction with body image can smother self-esteem and develop a depressive state, especially among dark or tan-skinned patients .The course of the disease is unpredictable, with peaks of anxiety, which makes the patient feel an urge to try different types of treatments. The fact that it can be rather hard to hide the white patches from the eyes of other people makes it difficult for the patient to cope with the disease on a daily basis.
Vitiligo is multifactorial and polygenic disease. The precise pathogenesis remains elusive; however, several theories have been proposed to explain the loss of epidermal melanocytes in this disorder. Proposed mechanisms are autoimmune, biochemical, oxidant-antioxidant, neural, and viral.
Helicobacter pylorus is one of the most common pathogens affecting human, infecting approximately 50% of the world’s population. It is found more frequently in developing countries than in industrialized countries, presumably due to poor sanitary conditions.
Several studies have pointed to a possible role of H. pylori infection in the pathogenesis of various extra gastric diseases. In the last years, several studies suggested that Helicobacter pylori infections play a role in the pathogenesis of a variety of skin diseases. The best evidence for such a link is found for two diseases: chronic urticarial and immune thrombocytopenic purpura. Other diseases that have a purported, but not yet proven link to H. pylori, are: cutaneous pruritus, Behçet’s disease, nodular prurigo and lichen planus. Lastly, single or few case reports have documented associations between Helicobacter pylori infection and rosacea, Alopecia areata, aphthous stomatitis, atopic dermatitis, Henoch-Schoenlein purpura and Sjögren syndrome.
Various mechanisms have been proposed in an attempt to explain the extra intestinal manifestations of H. pylori infections. These include: atrophic gastritis, an increase in gastric vascular permeability during infection, release of inflammatory mediators, molecular mimicry and systemic immune response. As an example, antigastric autoantibodies have been found in more than 30% of patients who are infected with H. pylori.
An increase in permeability of the gastric and intestinal mucosa in infected patients has also been demonstrated, and may result in increased exposure to alimentary antigens. Of note is that it is well known that the immunological response elicited by H. pylori is an important determinant of the amount of gastric mucosal damage. Thus the production of large amounts of various proinflammatory substances, such as cytokines, eicosanoids, and proteins of the acute phase, follows gastric colonisation by H pylori .This inflammatory response may lead to the development of antigen antibody complexes or cross reactive antibodies (by molecular mimicry) resulting in damage to other organs
Thus, one may propose that H. pylori may play a role in vitiligo through triggering an immune response. The aim of the present study was to evaluate the occurrence of H. pylori infection in vitiligo patients in order to determine a possible contribution in its pathogenesis This case-control study was carried out on 100 subjects.these included 75 patients of different clinical varieties of vitiligo and 25 age and gender matched apparently normal subjects as a control group.
The diagnosis of vitiligo was made on the basis of the patient’s history and the typical clinical features of discrete, well circumscribed depigmented macules and patches.
Every Patient was subjected to:
1-History
A) Personal history: Name, age, sex and occupation.
B) Present history: Onset, course, duration of vitiligo and dyspeptic symptoms.
All the studied cases were either newly diagnosed or old patients with completely depigmented lesions.
2-Examination
A) Full general examination to exclude associated systemic diseases as autoimmune diseases.
B) Detailed dermatological examination to identify type and distribuation of vitiligo .Assessment of disease activity was done according to VIDA score.
Every case and control was subjected to laboratory investigations including;
1. H. pylori specific IgG antibody in the serum by Enzyme Linked Immuno sorbent Assay (ELISA).
2. H. pylori antigen in stool by Enzyme Linked Immuno sorbent Assay (ELISA).
The data were collected, tabulated, statistically analyzed using an IBM personal computer with Statistical Package of Social Science (SPSS) version 20.
Differences were considered as follow:
P value of >0.05 non-significant
P value of <0.05 significant
P<0.001 was considered statistically highly significant.
In the present study higher Ag and antibody titres were significantly present in patients compared to controls. Patients also had higher rate of H. pylori infection. This may provide evidence about the association between H. pylori infection and vitiligo.
In the present study, higher rate of infection was associated with a disease duration of 1-5 years, low VIDA score and with inactive disease.
Regarding our results, increased prevalence of Helicobacter pylori infection in association with vitiligo, together with high level of antigen and antibody titres in vitiligo patients more than the healthy control group, with our concept that H. pylori may play a role in the pathogenesis of vitiligo.
Although our study supports a causal role of H. pylori in the pathogenesis of vitiligo, a large scale study is needed to confirm our finding.