Nickel sensitization in patients with gastro-esophageal reflux disease

Background: Gastro-esophageal reflux disease (GERD) leads to frequent medical visits, and available therapies fail in up to 40% of patients. Food allergies may be involved in GERD pathogenesis; however, allergens other than food have received little attention. Nickel allergy is common in the general population and some high-nickel foods are associated with GERD. However, the potential relationship between nickel allergy and GERD remains unaddressed. Aim: This study aimed to evaluate the prevalence of nickel sensitization in patients with and without GERD and to compare clinical and demographic features. Methods: This prospective, multicenter study included 210 adult GERD patients and 140 patients without GERD who presented at the general practitioner. All GERD patients had undergone treatment with proton pump inhibitors and upper digestive endoscopy within the previous five years. Demographic and clinical data were collected by questionnaire and patients underwent a nickel patch allergy test. Results: Patients with and without GERD presented similar characteristics, with the exception of nickel sensitization, which was significantly more prevalent among GERD patients than controls (39.5% vs. 16.4%; p=0.001). Nickel-positive GERD patients were more frequently female (90.4% vs. 65.4%, p=0.003) and asthmatic (18.1% vs. 4.7%; p=0.038), compared to nickel-negative GERD patients. At six-month follow-up, most of the patients, with or without nickel sensitization, reported improved symptoms without differences in drug prescription. Conclusion: Nickel sensitization is particularly prevalent in GERD patients seen in general practice. Whether allergies other than food allergy play a role in GERD remains to be elucidated.