Dietary Habits in Patients with Chronic Spontaneous Urticaria: Evaluation of Food as Trigger of Symptoms Exacerbation

BACKGROUND: Many patients with chronic spontaneous urticaria (CSU) identify different foods as triggers of their symptoms and frequently make dietary restrictions without enough information. OBJECTIVE: To explore the diet habits of CSU patients and estimate the clinical impact of the foods most frequently reported to be suspect. METHODOLOGY: Patients were interrogated about their clinical history of urticaria. Skin prick test and sIgE serum were done for most frequently reported foods by patients. Food challenge test was also performed. A group of healthy subjects was included to compare the dietary habits and the results of the diagnostic tests. RESULTS: Patients with CSU (n 245) and healthy (n 127) subjects were included. 164 (66%) subjects from CSU group and 31 (24%) from the control group reported at least one adverse reaction with foods. Food IgE sensitization was similar in both groups (17.5% versus 16.5%, respectively). 410 food challenge tests in 164 CSU patients and 38 in 38 control subjects were performed. 1.2% in CSU group and 0.7% in control group had a positive oral challenge test. CONCLUSION: Despite the high frequency of self-report by patients, foods are uncommon triggers of CSU. Nevertheless, food challenge tests have to be offered early during medical evaluation to avoid unnecessary restrictions.