# Increased Risk for Infections and Allergic Disease in Hereditary Hemorrhagic Telangiectasia

## TL;DR

People with hereditary hemorrhagic telangiectasia face higher risks of infections and allergies compared to others, suggesting a need for better awareness and preventive measures.

## Contribution

This study identifies increased infection and allergy risks in HHT patients and highlights gaps in prophylactic antibiotic use.

## Key findings

- HHT patients had significantly higher rates of allergies and infections like sinusitis and pulmonary infections.
- Only 38% of HHT patients took antibiotics before dental/surgical procedures, and 10% had undetected PAVMs.
- Iron-supplemented HHT patients had a 9-fold higher risk of sepsis compared to non-supplemented patients.

## Abstract

Background/Objectives: Hereditary hemorrhagic telangiectasia (HHT) is a rare disorder characterized by dilated blood vessels. Different immunological changes have been described in these patients. In this study, the predisposition of patients with HHT to infections and allergic diseases was assessed. Methods: Patients with HHT completed an online survey in English or German. Their data were compared to non-affected partners or friends. Results: A total of 430 out of 588 respondents with HHT answered our questions about infections and allergies. Patients with HHT suffered significantly more often from various types of allergies than their partners, especially type I allergies (n = 226/276, 82%), and had a higher risk for sinusitis, urinary tract infections, pulmonary infections, and abscesses. A total of 38% of the patients took antibiotics prior to dental or surgical procedures (n = 57/152), and, in 10% of these patients, pulmonary arteriovenous malformations (PAVMs) were not detected. On the other hand, 51% of patients with PAVM did not report a prophylactic antibiotic intake (n = 40/79). The patients who needed iron supplementations suffered more often from sepsis (OR: 9.00, 95%CI: 0.92–88.16). Conclusions: Compared to their non-affected controls, patients with HHT showed an increased risk for infections in different organs and allergic diseases. There is a need for campaigns raising greater awareness recommending prophylactic antibiotic intake in patients with PAVM.