Background: Chronic inducible urticaria (CIndU) is a subtype of chronic urticaria (CU) which require specific physical or non‐physical triggers to occur. They may be isolated or may coexist with chronic spontaneous urticaria (CSU). Despite their frequent appearance in dermatology clinics, there is scarce information on the distinguishing features among the most common subtypes of CIndU as well as isolated CIndU versus CSU plus CIndU.Objectives: To compare clinical and laboratory characteristics, and comorbid conditions among the most common CIndU types and isolated CIndU versus CSU plus CIndU.Methods: We retrospectively analysed CIndU patients and compared patients' demographic, clinical and laboratory characteristics across isolated CIndU, CSU plus CIndU, symptomatic dermographism (SD), cold urticaria (ColdU) and cholinergic urticaria (ChoU).Results: A total of 423 patients (~70% isolated CIndU, ~30% CSU plus CIndU, ~5% mixed CIndU subtypes) were included in the study. The most frequent CIndU subtypes were SD (68.6%; 290/423), ColdU (11.4%; 48/423) and ChoU (10.9%; 46/423). Isolated CIndU patients were younger than CSU plus CIndU (33.74 ± 12.72 vs. 37.06 ± 11.84, p = 0.010). Angioedema, emergency referrals, need for systemic steroids, comorbid systemic disorders were more frequent and baseline urticaria control test scores were lower in CSU plus CIndU patients (vs. CIndU, p < 0.001, p = 0.008, p < 0.001, p = 0.031, p = 0.036, respectively). Among CIndU subtypes, ChoU patients were younger (24.9 ± 12.2 vs. 34.47 ± 12.12 vs. 31.38 ± 14.95; p < 0.001) and had male predominance (p < 0.001) while SD patients had no angioedema (p < 0.001) and had higher frequency of increased total IgE levels (p = 0.006).Conclusions: Isolated CIndU and CSU plus CIndU seems to be different endotypes of CU where CSU plus CIndU presents a more severe and refractory course. There are distinctive features of each CIndU subtype. These suggest involvement of different pathomechanistic pathways in these subtypes that need to be clarified in future studies.

Chronic Spontaneous Urticaria (CSU) is characterized by recurrent wheals and/or angioedema for longer than 6-weeks. Guidelines recommend Omalizumab (Oma) as first-line and Cyclosporine-A (Cs-A) as second-line treatment in antihistamine resistant CSU. This step-wise algorithm might be time-consuming and costly. To determine indicators of response to Oma or Cs-A in CSU patients. We retrospectively analyzed data from seven centers in Turkey; the inclusion criteria for patients were to receive both Oma and Cs-A treatment (not concurrently) at some point in time during their follow-up. Clinical and laboratory features were compared between groups. Among 110 CSU patients; 47 (42.7%) were Oma-responders, 15 (13.6%) were Cs-A-responders, and 24 (21.8%) were both Oma and Cs-A responders and 24 (21.8%) were non-responders to either drug. High CRP levels were more frequent in Cs-A-responders (72.7% vs. 40.3%; p = 0.055). Oma-responders had higher baseline UCT (Urticaria Control Test) scores (6 vs. 4.5; p = 0.045). Responders to both drugs had less angioedema and higher baseline UCT scores compared to other groups (33.3% vs. 62.8%; p = 0.01 and 8 vs. 5; p = 0.017). Non-responders to both drugs had an increased frequency in the female gender and lower baseline UCT scores compared to other groups (87.5% vs. 61.6%; p = 0.017 and 5 vs. 7; p = 0.06). Retrospective nature, limited number of patients, no control group, the lack of the basophil activation (BAT) or BHRA (basophil histamine release assay) tests. Baseline disease activity assessment, which considers the presence of angioedema and disease activity scores, gender, and CRP levels might be helpful to predict treatment outcomes in CSU patients and to choose the right treatment for each patient. Categorizing patients into particular endotypes could provide treatment optimization and increase treatment success.

Introduction: Chronic inducible urticaria (CIndU) is a subtype of chronic urticaria (CU), which requires specific triggers to occur. Despite their common occurrence, treatment response rates and predictors of treatment responses are largely lacking in the literature. This study evaluates antihistamine (AH) and omalizumab response rates in the most common CIndU subtypes and examines whether certain features can predict treatment responses. Methods: We retrospectively analyzed CU patients with at least one CIndU subtype and performed comparisons between subgroups, in a total of 423 patients (70% CIndU, 30% chronic spontaneous urticaria [CSU] plus CIndU). Results: The treatment response rates in CIndU were 51.6%, 51.5%, and 86.5% with standard-dose second-generation H1-antihistamines (sgAHs), updosed/combined sgAH, and omalizumab, respectively. Overall AH response was higher in CIndU than CSU plus CIndU (78.3% vs. 62%, p = 0.002) and in symptomatic dermographism (SD) and cold urticaria (ColdU) than cholinergic urticaria (ChoU) (83.2% vs. 78.3 vs. 60.9%, p = 0.04). AH-refractory patients had a longer disease duration (45.2 ± 56.7 months vs. 37 ± 51.9 months, p = 0.04), more angioedema, accompanying CSU, mixed CIndU subtypes (37.5% vs. 21.1%, p = 0.003; 45.1% vs. 27.1%, p = 0.002; 8.8% vs. 2.4%, p = 0.014), and lower baseline urticaria control test scores (5.86 ± 3.3 vs. 8.6 ± 3.6, p < 0.001) than AH-responsive patients. Conclusion: CIndU exhibits a good response to both AHs and omalizumab. Notably, the response to AHs is more pronounced in SD and ColdU compared to ChoU. Disease duration, angioedema, accompanying CSU, mixed CIndU, and lower baseline UCT scores may be used to predict AH treatment outcome in CIndU.

Background: Chronic urticaria (CU) is a systemic disorder which is characterized by recurrent wheals and/or angioedema lasting more than 6 weeks. Sex hormones have been suggested to play a role in CU pathogenesis, however, their clinical implications have not been adequately described in the literature. Objective: To determine whether conditions that change sex hormone levels such as puberty, menstruation, pregnancy, breastfeeding, and menopause affect the course of CU. Methods: This cross-sectional questionnaire study was conducted on female CU patients at Okmeydani Training and Research Hospital UCARE Center between 2016 and 2017. The open-ended questionnaire consisted of questions evaluating the effects of hormonal changes on disease course. Results: A total of 111 female CU patients were included in the analysis. During the perimenstrual period, CU symptoms worsened in 29% of patients but improved in 4.8%. The disease course did not change in the majority of patients during puberty, pregnancy, lactation, or menopause (100%, 96%, 83.8%, and 95.6%, respectively). Conclusions: Contrary to expectations, a change in sex hormone levels had no effect on the course of CU in the majority of cases. However, disease activity increased in one-third of CU patients during the perimenstrual period.

Aims: Chronic spontaneous urticaria (CSU) is one of the most prevalent skin disorders. Helicobacter pylori (HP) infection has been linked to CSU, and HP eradication therapy has been questioned as a viable treatment option. However, studies have produced contradictory results. In addition, recent studies suggest that gastritis, rather than HP bacteria, may be responsible for CSU symptoms. Herein, we aimed to ascertain the prevalence of HP infection in CSU, explore associations between HP infection, gastritis, and CSU severity or treatment response in CSU, and investigate the impact of HP eradication therapy on the CSU course. Methods: We retrospectively analyzed CSU patients who were investigated for HP infection. Patient characteristics, in-clinic urticaria activity scores (ic-UAS) and urticaria control test (UCT) scores, and CSU treatment responses were compared across different patient groups. Results: The study included 325 CSU patients, of whom 57.2% were HP-positive and 60.9% had gastritis. The mean baseline ic-UAS showed no difference between HP-positive and HP-negative patients (2.55±2 vs 2.45±1.98, p>0.05) or between patients with and without gastritis (2.33±2 vs 2.51±2, p>0.05). HP-positive patients had higher rates of elevated CRP levels (45% vs 29.9%, p=0.023) and ASST positivity (54.8% vs 29.8%, p0.05). Conclusion: Over half of CSU patients have been found to be infected with HP. However, the HP bacterium itself, the eradication of HP, or gastritis have no significant effect on CSU severity or treatment response.