Clinical Evaluation and Outcome Measures of Chronic Spontaneous Urticaria and Chronic Inducible Urticaria

Chronic spontaneous urticaria (CSU) and chronic inducible urticaria (CIndU) are debilitating skin diseases characterized by recurrent itchy wheals and/or angioedema, with a considerable negative impact on the patient’s quality of life (QoL). Accurate clinical evaluation is important for diagnosis, disease monitoring, and guiding treatment. In CSU, it is primarily based on a detailed history, selected laboratory investigations, and patient-reported outcome measures (PROMs). In CIndU, objective provocation tests and critical threshold testing (CTT) are additionally useful. PROMs have emerged as indispensable tools in assessing disease activity, impact, and control from the patient’s perspective. They enhance disease monitoring, support treatment decisions, and facilitate individualized, patient-centered care, and are recommended in routine clinical care and research. Recently, digital tools such as the CRUSE (Chronic Urticaria Self Evaluation) app have further advanced PROM integration, enabling real-time disease tracking and improved clinical workflows. In CIndU, objective provocation tests and CTT help to identify specific triggers and quantify individual stimulus thresholds. A structured approach based on the "Assess–Act–Adjust" principle facilitates optimal management by linking PROM results, diagnostic tests (eg, CTT), and other data with therapeutic strategies. Its implementation in urticaria care supports personalized medicine, aiming to achieve complete disease control and to normalize the patient’s QoL.