Gut microbiome alterations in hereditary angioedema

Area of Science:

• Microbiome research
• Immunology
• Gastroenterology

Background:

• Hereditary angioedema (HAE) is a rare genetic disorder with unpredictable clinical variability.
• Current clinical practices lack reliable predictors for HAE onset and severity.
• Investigating the gut microbiota may elucidate HAE pathogenesis and heterogeneity.

Purpose of the Study:

• To determine if HAE patients exhibit gut dysbiosis.
• To identify potential gut microbial biomarkers for HAE episodes.

Main Methods:

• Collected fecal samples and clinical data from HAE patients and healthy family members.
• Sequenced the 16S ribosomal RNA gene to analyze gut microbiota diversity.
• Grouped patients based on recent HAE attack status and clinical symptoms.

Main Results:

• Reduced microbial richness and diversity were observed in HAE patients with recent attacks, especially those with abdominal symptoms.
• Patients with recent attacks showed decreased Firmicutes, increased Proteobacteria, and a rise in pathogenic bacteria.
• Gut dysbiosis improved with danazol or tranexamic acid treatment.
• A five-bacterial biomarker (Bifidobacterium, Lachnospira, Paraprevotella, Desulfovibrio, Staphylococcus) was proposed for detecting recent HAE episodes.

Conclusions:

• Gut microbiome alterations are associated with HAE.
• Bacterial changes may play a role in HAE etiology and edema episodes.
• Findings suggest potential for microbial biomarkers in predicting HAE course and evaluating treatment efficacy.