Lachnospira is a signature of antihistamine efficacy in chronic spontaneous urticaria.

Chronic spontaneous urticaria (CSU) is a mast cell-driven disease with many advances in its aetiology and pathogenesis over the past years. The main treatment of CSU is oral second-generation antihistamines. However, only an average of 50% of CSU patients responded adequately to conventional or quadruple doses of non-sedative antihistamines. Meanwhile, gut microbiota can affect the efficacy of drugs. The purpose of this study was to investigate the relationship between gut microbiota and the efficacy of antihistamines in patients with CSU. The patients with CSU were divided into responders and non-responders according to the efficacy of antihistamine monotherapy. The gut microbiota of faecal samples from 15 responders and 15 non-responders was detected by 16S rDNA sequencing, and the differential bacterial species between the two groups were verified by quantitative polymerase chain reaction (qPCR). Additional faecal samples from 30 responders and 30 non-responders were used as an extended cohort to further verify the above differential bacterial species by qPCR. Lachnospiraceae and its subordinate taxa were found to be the main differences in gut microbiota between responders and non-responders. The abundance of Lachnospira in responders was higher than that in non-responders. Lachnospira exhibits moderate diagnostic value in evaluating the efficacy of antihistamine. Lachnospira is a signature for predicting the efficacy of antihistamine in patients with CSU.

Clinical difference between single subtype and mixed subtype chronic urticaria: A retrospective study.

BACKGROUND: The subtypes of chronic urticaria share a common clinical expression, but may show differences phenotypically. Meanwhile, two or more different subtypes of chronic urticaria can coexist in any given patient which may involve different phenotypes. AIMS: The study aims to compare the two phenotypes in terms of demographics, clinical profile and treatment response. METHODS: In this retrospective study, 2678 chronic urticaria patients were divided into the single subtype chronic urticaria group and mixed subtype chronic urticaria group as was appropriate.The differences in the clinical features, possible causes, urticaria activity score of seven days, dermatology life quality index score, laboratory investigations and response to treatments were evaluated among the two groups. RESULTS: An obvious female predominance was detected in chronic urticaria, especially in mixed subtype chronic urticaria patients. Of the 2678 chronic urticaria patients, there were 837(31.25%) mixed subtype chronic urticaria. Chronic spontaneous urticaria combined with symptomatic dermographism was the most common group in the mixed subtype chronic urticaria. Patients with mixed subtype chronic urticaria were more likely to have associated chest tightness/shortness of breath and showed greater urticaria activity. In patients with single subtype chronic urticaria, the positive rate of family history with allergic rhinitis, asthma or urticaria was lower. Based on evaluation of the treatment, control with second-generation antihistamines at licensed doses was achieved in only 38.83% of mixed subtype chronic urticaria patients, compared with 56.32% of patients with single subtype. LIMITATIONS: First, this study was a single-center design retrospective study. Second, omalizumab treatment was not included. Third, the differences between different subtypes of mixed subtype chronic urticaria were not discussed in detail. CONCLUSION: This study showed that mixed subtype chronic urticaria had some distinct features. Comprehensive knowledge about it may help us define effective therapeutic strategies and improve symptom control and the quality of life for chronic urticaria patients.

Biomarkers of Gut Microbiota in Chronic Spontaneous Urticaria and Symptomatic Dermographism.

Background: Chronic urticaria (CU) is a chronic inflammatory skin disease associated with Th2 immune response. The two most common subtypes of CU, i.e., chronic spontaneous urticaria and symptomatic dermographism (CSD), often coexist. However, the pathogenesis of CSD is still unclear. Gut microbiota plays an important role in immune-related inflammatory diseases. The purpose of this study was to explore the correlation between gut microbiota and CSD. Methods: A case-control study was conducted on CSD patients as well as gender- and age-matched normal controls (NCs). The 16S ribosomal DNA sequencing of fecal samples was used to detect the gut microbiota of all subjects. QPCR was used to further verify the species with differences between the two groups. Results: The alpha diversity of gut microbiota decreased in CSD patients, accompanied by significant changes of the structure of gut microbiota. Subdoligranulum and Ruminococcus bromii decreased significantly in CSD patients and had a potential diagnostic value for CSD according to receiver operating characteristic curve (ROC) analysis. Enterobacteriaceae and Klebsiella were found to be positively correlated with the duration of CSD, while Clostridium disporicum was positively correlated with the dermatology life quality index (DLQI). Conclusions: The gut microbiota of CSD patients is imbalanced. Subdoligranulum and Ruminococcus bromii are the gut microbiota biomarkers in CSD.

Identification of gut microbiota signatures in symptomatic dermographism.

Symptomatic dermographism (SD) is a recurrent inflammatory skin disease related to immunity; however, the details remain elusive. In view of the important role of gut microbiota in immune regulation, the purpose of this study is to investigate the alterations of gut microbiota in SD and explore the potential bacterial biomarkers for diagnosis. A case-control study including SD patients and normal controls (NCs) was carried out. Gut microbiota of the participants was analysed by the 16S rDNA sequencing of faecal samples. The linear discriminant analysis effect size and the receiver operating characteristic curve (ROC) analysis were used to identify the bacterial biomarkers. Forty-four participants were included in this study. The alpha-diversity and beta-diversity of gut microbiota differed significantly between SD patients and NCs. The abundance of Verrucomicrobia, Ruminococcaceae and their subordinate taxa were reduced in SD patients, while Enterobacteriales and its subordinate taxon exhibited higher relative abundance compared with NCs. Subdoligranulum and Ruminococcus bromii showed a potential diagnostic value for SD, and Prevotella stercorea was negatively relevant to duration of SD. Furthermore, the pyruvate, butyric acid and histamine metabolism pathway were likely to be involved in the pathogenesis of SD. Our results revealed that the gut microbiota of SD patients experienced obvious changes, and Verrucomicrobia, Ruminococcaceae and Enterobacteriales were microbiota signatures for SD.