alopecia areata ( aa ) is a nonscarring alopecia that genetic and immunological causes have been suggested to be affective in the pathogenesis of the disease . prevalence of aa in the united states is 0.10.2% with an estimated lifetime risk of 2% . aa is characterized by sudden onset of hair loss in one or more regions , generally head , and some other parts of the body covered with hair that can be patchy , totalis ( 100% terminal hair loss on the scalp ) , universalis ( 100% terminal hair loss on the scalp and body ) , and ophiasis ( hair lose around the periphery of the scalp ) . about 766% of the patients have nail involvement , and the most common form of nail involvement is pitting . various studies revealed that aa can accompany with anxiety disorders , depression , and social phobia . the psychological and social role of hair , particularly scalp hair , is much more important , in comparison to the biological aspect . hair can be a social characteristic of sex , age , values , and even being the member of a group . beyond the social meaning of hair , it plays an important role in the identity and self - imagination of the body . hair also plays a role in physical attraction and is an important factor in interpersonal relationships . in some studies , aa is reported accompanied with other autoimmune illnesses such as hashimoto 's thyroiditis , vitiligo , diabetes , lichen planus , and also in a few reports , celiac disease ( cd ) ( gluten - sensitive enteropathy ) . although diagnosis of aa is usually facile , treatment is not . curative treatment does not exist yet cd is a small intestinal disease characterized by villous atrophy , mucosal inflammation , and crypt hyperplasia , which occurs upon exposure to dietary gluten and which exhibits improvement after the removal of gluten from the diet . for the diagnosis of cd , initially , serological tests are recommended . other diagnostic procedures include endoscopy , biopsy of the small intestine , oral tolerance tests ( xylose and lactulose ) , and radiographic studies of small intestine . the prevalence of gliadin antibody in patients with aa is estimated to be about 1 in 116 . in another study , prevalence of anti - gliadin in patients with aa is estimated to be about 18 in 100 . the chronic and recurrent nature of aa and its stressful effect on patients make this study important . unfortunately , there is no cure for aa . according to most of the reports , hair regrew in patients with aa and cd after they accepted a gluten - free diet . aa is a skin disease and can be easily diagnosed , but can be a manifestation of an internal disease such as celiac , so cd can be treated before any complication . in previous studies , assessment of these three antibodies at the same time can help to understand the relationship between these two diseases . it was a case  control study conducted at one of the biggest university of medical sciences of center of iran , in which patients with aa referred to dermatology clinics were analyzed and studied . thirty - five patients were selected through simple sampling in patients with aa and control group . data such as age , sex , duration of disease ( classified according to the olsen 's study ) , family history of aa ( first degree ) , and nail involvement were collected in questionnaires . all patients with aa were considered to be the case group and all healthy participants without a past history and family history of aa , cd , and other autoimmune diseases ( vitiligo , hashimoto 's hypothyroidism , etc . ) were considered as the control group . exclusion criteria included patients who were treated with a gluten - free diet , pregnant women , nursing mothers , and people who did not cooperate with the investigation . after an explanation of how the process works , a written informed consent was signed by the participants . ethical approval for our study was obtained from the isfahan university of medical sciences ( ethical code : 393232 ) . both groups were referred to an accredited laboratory for the following tests : anti - gliadin iga , anti - gliadin igg , and anti - tissue transglutaminase iga . for this purpose , first , taking a small sample of blood ( 5 ml clot blood without anticoagulant ) from a vein in arm was necessary and then it was centrifuged for 10 min at around 25003000 . finally , the laboratory examined the obtained serum samples from centrifugation in elisa method with binding site 's kits of the uk . a normal range of tests was defined according to the laboratory standards and finally was reported as positive / negative . the statistical analyses of the results were performed using chi - square test ( for qualitative data ) and t - test ( to compare the means of two groups and for quantitative data ) in spss 16 for windows ( ibm corporation , ny , usa ) . in this study , the significance level was set at p < 0.05 . it was a case  control study conducted at one of the biggest university of medical sciences of center of iran , in which patients with aa referred to dermatology clinics were analyzed and studied . thirty - five patients were selected through simple sampling in patients with aa and control group . data such as age , sex , duration of disease ( classified according to the olsen 's study ) , family history of aa ( first degree ) , and nail involvement were collected in questionnaires . all patients with aa were considered to be the case group and all healthy participants without a past history and family history of aa , cd , and other autoimmune diseases ( vitiligo , hashimoto 's hypothyroidism , etc . ) were considered as the control group . exclusion criteria included patients who were treated with a gluten - free diet , pregnant women , nursing mothers , and people who did not cooperate with the investigation . after an explanation of how the process works , a written informed consent was signed by the participants . ethical approval for our study was obtained from the isfahan university of medical sciences ( ethical code : 393232 ) . both groups were referred to an accredited laboratory for the following tests : anti - gliadin iga , anti - gliadin igg , and anti - tissue transglutaminase iga . for this purpose , first , taking a small sample of blood ( 5 ml clot blood without anticoagulant ) from a vein in arm was necessary and then it was centrifuged for 10 min at around 25003000 . finally , the laboratory examined the obtained serum samples from centrifugation in elisa method with binding site 's kits of the uk . a normal range of tests was defined according to the laboratory standards and finally was reported as positive / negative . the statistical analyses of the results were performed using chi - square test ( for qualitative data ) and t - test ( to compare the means of two groups and for quantitative data ) in spss 16 for windows ( ibm corporation , ny , usa ) . in this study , the significance level was set at p < 0.05 . the average age in the case and control group was 28.11  7.1 and 27.6  7.2 years , respectively ( p = 0.62 ) . nearly , 58.8% and 41.2% of the patients of the case and control groups were males , respectively ( p = 0.15 ) . regarding the type of aa , 88.6% of the patients had patchy aa , 8.6% and 2.8% of them had totalis and universalis aa , respectively . concerning the nail involvement , 88.5% of the patients had no involvement , but 5.7% , 2.9% , and 2.9% of them had pitting , ridging , and onycholysis , respectively . most of the participants in the case group did not have any positive familial history of aa ( 82.9% ) . forty percent of the patients suffered from the disease for <3 months and 8.6% of the patients suffered from aa over 5 years [ table 1 ] . frequency and duration of alopecia areata in the case group the serum of one aa patient ( 2.8% ) was positive for antibodies . there was no significant difference between the two groups based on chi - square test ( p = 0.31 ) . in the current study , the serum of one aa patient ( 2.8% ) was positive for antibodies . the control group was seronegative for these antibodies . until now , the results of studies about the relationship between aa and cd are controversial . several studies declare an association between aa and cd . in 1995 , one of the first research reports connecting aa with cd was published . they reported a 14-year - old boy with universalis alopecia , completely regrew after he accepted a gluten - free diet . this case report , and a few others , alerted the physicians to monitor a large group of patients with alopecia for cd . in fact , they did determine a relatively high rate of cd in their patients , much greater than accidental . on the basis of this analysis , they suggested that cd antibody testing should be carried out in all patients with aa . a few case reports proposed an association between cd and aa . in a prospective trial of 256 aa patients , 6 had positive tissue transglutaminase and endomysial with positive biopsy . in another study , volta et al . estimated that the prevalence of gliadin antibody in patients with aa was 1 in 116 , which was about 2.5 times more than the prevalence of this antibody in normal people . estimated the prevalence of anti - gliadin antibodies in patients with aa to be about 18100 . however , results of this study showed that in this population , there was no significant difference between the two groups in terms of celiac autoantibodies ( anti - gliadin iga , anti - gliadin igg , and anti - tissue transglutaminase iga ) , which could be due to different demographic compositions . in this study , the prevalence of antibodies had not been determined , but compared between the case and control groups . on the other hand , in this study , all these three antibodies had been checked at the same time , which seems to increase the accuracy of this study . if the previous studies had checked these three autoantibodies at the same time , they could not find statistically significant positive results . however , it seems that evaluating the prevalence of antibodies instead of frequency distribution of the antibodies was the advantage of other studies . in general , aa may occur at any age , but the disease was more common in younger age and under 20 years . in seirafi 's study , it can be explained through the fact that children 's clinics were separated from adult 's clinics . in one study , more than 66% of the patients were younger than 30 years old and only 20% were over 40 years old . aa affected both males and females . in one study , the affected men were more than women . in this study , in halaji 's study , the most frequent form of aa was patchy which was consonant with this study . the prevalence of nail involvement in aa patients was estimated at a wide range of 7% to 66% in different studies . , most patients ( 88.5% ) did not have nail involvement in the study group . perhaps , the reason was that over 50% of our patients suffered from the disease less than a year , and still there had not been enough time for nail involvement . reported that 72% of the patients had nail changes and the most common form was pitting , which was similar to this study . , the frequency of positive familial history had been reported about 327% . in another study , the prevalence of positive familial history of aa was estimated to be about 1422% . in this study , 17.1% of the cases had a positive familial history , which was in the range of other studies . forty percent of the patients suffered from aa for <3 months , and 6.8% of the patients suffered from aa over 5 years . in some studies , the average duration of disease was 10.3 months with a range within 1 week to 8 years which was similar to this study . unlike many studies , this study shows that the frequency distribution of celiac autoantibodies ) anti - gliadin iga , anti - gliadin igg , and anti - tissue transglutaminase iga ) in patients with aa does not differ from the normal population . thus , we show here that the biological tests to search for cd do not bring information and proof enough , and it is why we recommend another approach to disclose gluten intolerance in aa patients .