Such an analysis might otherwise have added to the understanding of environmental factors in the pathogenesis of the two diseases. Rash and pruritus may occur in a number of disorders but many of these have distinct ICD codes and are not coded as urticaria. risk=47/100,000 person-years). Corresponding figures for chronic urticaria were 24/100,00 person-years and 12/100,000 person-years. Patients with CD Histone-H2A-(107-122)-Ac-OH were also at increased risk of having both urticaria (odds ratio, OR=1.31; 95%CI=1.12C1.52) and chronic urticaria (OR=1.54; 95%CI=1.08C2.18) the CD diagnosis. Conclusion This study suggests that CD is usually associated with urticaria, especially chronic urticaria. estimates that between 15C24% of people in the United States will experience acute urticaria, angioedema, or both at some point in their lives.[3] Chronic urticaria (duration 6 weeks)[1] is seen in about 0.5C1% of the general population.[4, 5] Although this is less common than acute urticaria, chronic urticaria is associated with a substantial decrease in Rabbit Polyclonal to ATG4D quality of life.[6] Celiac disease (CD) is an immune-mediated disease occurring in about 1C2% of the Western populace.[7] CD is triggered by gluten exposure in genetically sensitive individuals, requiring lifelong treatment with a gluten-free diet (GFD).[8] It has been linked to an excess risk of mortality,[9, 10] malignancy,[11, 12] and other comorbidities, especially autoimmune diseases.[13, 14] Over the past few years, a number of case reports have indicated a positive association between urticaria and CD, [15C18] but also with other autoimmune diseases[19]. Patients with CD also demonstrate an increased mucosal permeability and hypothetically an increased passage of antigens, and subsequently the formation of immune complex, may contribute to an extra risk of urticaria.[20] Recent reports link cold urticaria to CD[21] and to autoimmunity.[22] So far, there are only three case-control studies on urticaria and CD[19, 23, 24] (no cohort studies available) and these present discrepant results (Table 1). Explanations for the conflicting results include small sample size (together the two studies involved only five patients with both CD and urticaria),[23, 24] and single-center source populations with patient characteristics that may differ from that of the Histone-H2A-(107-122)-Ac-OH average patient with chronic urticaria. Additional limitations are the lack of adult patients and that none of the studies examined the relationship between CD and future urticaria. Just recently, Israeli researchers presented data from a health database on chronic urticaria and a number of autoimmune diseases.[19] That case-control study found an almost 27 occasions increased risk of CD in patients with chronic urticaria but confidence intervals were wide with the 95% upper confidence interval exceeding 100.[19] These data contrast with the prevalence of tissue transglutaminase antibodies in the same patients with chronic urticaria, (0.3% of female patients and 0.1% of male patients) were antibody positive),[19] levels that are actually lower than in most screening studies of the in the Western world.[25] Table 1 A summary of previous publications on celiac disease in patients with urticaria. analyses included stratifications for age (0C19; 20C39; 40C59 and 60+ years), calendar period (?1989, 1990C1999 and 2000?) and sex. Another analysis involved follow-up time ( 1 year 1C4.99 years and 5 years). The latter analysis was carried out because we have seen that patients with CD are often at high relative risks of any comorbidity in the first 12 months after biopsy, potentially because of increased surveillance and ascertainment bias. Secondary analyses In subanalyses we adjusted for the following potential confounders: education and country of birth; but also for type 1 diabetes, rheumatoid arthritis, lupus erythematosus and autoimmune thyroid disease (see Appendix for ICD codes) since both CD and urticaria have been linked to these autoimmune disorders. In a second subanalysis we excluded individuals with a record of diabetic sulphonylureas (ATC code A10BB), aspirin (N02BA01), non-steroidal anti-inflammatory drugs (M01A), Histone-H2A-(107-122)-Ac-OH penicillin (J01C), clotrimazole (D01AC01), sulfonamides (J01E) and anticonvulsants (N03) since these medications may cause itch or urticaria. We also excluded individuals with either a diagnosis of the parasitic contamination ascariasis or a record in the Swedish Prescribed Drug Register[32] of anti-parasitic treatment (P02C) that could signal ascariasis contamination (ascariasis may imitate urticaria). The Swedish Prescribed Drug Register[32] started in July 2005 and accounts for some 80C90% of all drug use in Sweden. In a fourth subanalysis we excluded individuals with a diagnosis of Histone-H2A-(107-122)-Ac-OH dermatitis herpetiformis to eliminate the possibility that one skin disorder would lead to an increased health care contact with surveillance bias and an increased risk of misdiagnosis as urticaria. In a fifth subanalysis we restricted our outcome to patients having urticaria and a record of either antihistamines (R06) or oral steroids (Betamethasone, H02AB01; Prednisolone, H02AB06) since these medications are the most common treatment for urticaria in Sweden. Because some reports indicate a link between Helicobacter pylori contamination and chronic urticaria[33] and because Helicobacter pylori may be misclassified as CD (or to a larger extent these patients may be.