Chronic spontaneous urticaria (CSU) - the frustrating condition causing recurrent hives without an obvious trigger - may have a surprising connection to the gut, according to a recent study published in Scientific Reports.
Researchers from Turkey compared serum zonulin levels (a marker of increased intestinal permeability, often called "leaky gut") in 65 patients with CSU and 65 matched healthy controls.
Zonulin regulates tight junctions in the intestinal lining; when elevated, it suggests greater gut permeability, potentially allowing antigens or bacterial products to enter the bloodstream and trigger immune responses.
Zonulin regulates tight junctions in the intestinal lining; when elevated, it suggests greater gut permeability, potentially allowing antigens or bacterial products to enter the bloodstream and trigger immune responses.
The results were clear: CSU patients had significantly higher mean serum zonulin levels (132 pg/ml) compared to controls (83 pg/ml), with a highly significant difference.
Interestingly, patients who also had concomitant inducible urticaria (e.g., triggered by cold, pressure, or other stimuli) showed even higher zonulin levels than those with pure spontaneous urticaria.
The findings support the idea that autoimmunity plays a role in CSU pathogenesis and suggest that increased intestinal permeability could contribute to the condition - perhaps by facilitating immune activation or molecular mimicry.
While this is an association (not causation), it opens doors for future research into gut-targeted approaches, such as microbiome modulation or zonulin-lowering strategies, as potential adjuncts to standard antihistamine or biologic therapies.
While this is an association (not causation), it opens doors for future research into gut-targeted approaches, such as microbiome modulation or zonulin-lowering strategies, as potential adjuncts to standard antihistamine or biologic therapies.
This small but intriguing case-control study adds to the growing evidence linking gut barrier function to chronic inflammatory and autoimmune skin diseases.
https://www.nature.com/articles/s41598-026-35394-9