Chronic inducible urticaria: a systematic review of treatment options.

BACKGROUND: Chronic inducible urticaria (CindU) is a condition characterized by the appearance of recurrent wheals, angioedema or both, as a response to specific and reproducible triggers. OBJECTIVE: To systematically assess the evidence on the efficacy and safety of treatment options for CindU. Results were used to inform the 2017 update of "The EAACI/GA METHODS: Randomised controlled trials (RCTs) and controlled studies (CCTs) were systematically searched in various databases. Included studies were evaluated with the 'Cochrane Risk of Bias tool'. Where possible, results from single studies were meta-analyzed, applying the Mantel-Haenszel approach using a random-effects model (Der Simonian-Laird). RESULTS: We identified 30 studies that included patients with cold urticaria, symptomatic dermographism, delayed pressure urticaria, or cholinergic urticaria,. No studies on other forms of CindU were eligible. Risk of bias was often rated as unclear or high. Overall, second generation antihistamines were more effective than placebo and the available data indicate that updosing may be effective. Omalizumab proved to be effective in patients with symptomatic dermographism, who did not respond to antihistamines. Detailed results are given for each type of CindU. CONCLUSIONS: The available evidence is limited by small samples, heterogeneous efficacy outcomes, and poor reporting quality in many of the included studies. The findings are congruent with the suggested stepwise approach to treating CindUs. However, the data do not allow for drawing specific conclusions for specific subtypes of CindU.