# Prevalence of allergic sensitization to Platanus occidentalis among adults with allergic rhinitis: A multicenter study

## TL;DR

This study finds that about 20% of adults with allergic rhinitis in Mexico are sensitized to sycamore pollen, suggesting it should be considered in allergy testing.

## Contribution

The study provides the first multicenter data on sycamore pollen sensitization prevalence in allergic rhinitis patients in Mexico.

## Key findings

- The overall prevalence of sensitization to Platanus occidentalis was 20.8% among 404 patients.
- Tree pollens, weeds, fungi, and pet epithelia were associated with sycamore pollen sensitization.
- Sensitization rates varied by region, with the highest in the southeast (22.4%).

## Abstract

In the Americas there are few studies that have evaluated the frequency of allergic sensitization to Platanus occidentalis or sycamore pollen in adult patients with allergic rhinitis (AR).

To determine the prevalence of allergic sensitization to P. occidentalis and to identify factors associated with its presentation.

A cross-sectional study was carried out in 3 centers distributed in the northwest, west, and southeast of Mexico. Allergic sensitization to P. occidentalis was determined with a skin prick test. Prevalence and 95% confidence intervals (CI) were estimated.

A total of 404 patients were included, women were 233 (57.7%); the age mean was 33.8 ± 12.9 years. The overall prevalence of sensitization to P. occidentalis was 20.8% (95% CI, 17.1%–25.0%); in the northwestern: 15.9% (95% CI, 9.6%–25.1%); in the western: 21.8% (95% CI, 15.4%–29.9%); and in the southeastern: 22.4% (95% CI, 17.1%–38.8%). Multivariate analysis showed to the following allergens as factors associated with sycamore allergic sensitization: tree pollens (OR, 3.19; P = 0.001), weeds (OR, 2.49; P = 0.004), fungi (OR, 1.96; P = 0.014), and dog or cat epitheliums (OR, 1.88; P = 0.018).

Allergic sensitization to P. occidentalis pollen in AR patients is not an infrequent event; consequently, we recommend doing the challenge test in all patients with this allergen, especially in those regions where the tree is present.