# Comparative Analysis of Pediatric and Adult Mastocytosis: Clinical Presentation, Triggers, and Treatment Patterns from a Tertiary Care Registry

## TL;DR

This study compares how mastocytosis presents and is treated in children versus adults, finding key differences in disease types and medication use.

## Contribution

The study provides new insights into age-related differences in mastocytosis clinical features and treatment patterns.

## Key findings

- Cutaneous mastocytosis was exclusive to children while systemic mastocytosis was more common in adults.
- Adults with systemic mastocytosis had higher median age and higher epinephrine use compared to children.
- No pediatric patients required epinephrine for symptom control.

## Abstract

Background: Mastocytosis is a rare hematologic disorder, classified into cutaneous mastocytosis (CM) and systemic mastocytosis (SM). Understanding age-related differences in presentation and management is essential for individualized care. Methods: Data from patients recruited from the Montreal Children’s and Montreal General Hospitals between 2015 and 2024 were analyzed. Descriptive statistics were employed to present patient demographics, clinical characteristics, and medication usage. Statistical analyses included Fisher’s exact test for categorical variables and t-tests or non-parametric equivalents for continuous variables. Results: A total of 63 patients were included, comprising 39 children and 24 adults. Children had a median age of 1.9 years, while adults had a median age of 49.3 years. CM was exclusively prevalent in children (100.0%), while SM was more common in adults (45.8%). Adults with SM had a significantly higher median age than CM (49.4 versus 44.7 years, respectively, p = 0.03). Epinephrine use was more frequent in adult SM patients (36.4% versus 0%, respectively, p = 0.03). No pediatric patients required epinephrine for symptom control. Conclusions: This study highlights important clinical differences between pediatric and adult mastocytosis. CM was more common in children while SM predominated in adults and was associated with greater flare severity and higher tryptase levels.