Systemic mastocytosis (SM) causes more severe symptom flares than cutaneous mastocytosis (CM), found a study examining mastocytosis in adults and children. Results from the study were recently published in the journal Children.
Researchers studied patients treated at the Montreal Children’s Hospital and the Montreal General Hospital between 2015 and 2024. The study included 63 patients: 39 children and 24 adults. The median age was 1.9 years for children and 49.3 years for adults.
All children in the study had CM, the form of mastocytosis where abnormal mast cells build up in the skin and create itchy sores. Meanwhile, nearly half of the adults in the study (45.8%) had SM.
Adults with SM were older than those with cutaneous mastocytosis (49.4 versus 44.7 years).
Antihistamines were the most common treatment in both children and adults, followed by steroids.
More than one-third of adults with SM needed epinephrine to treat severe reactions, while none of the adults and children with cutaneous mastocytosis required it. This shows that SM carries a higher risk of dangerous allergic reactions.
Read more about SM treatment and care
Adults with SM also had higher levels of tryptase, a blood marker that shows how many mast cells are in the body. High tryptase levels are used to help diagnose SM and are linked to a greater risk of anaphylaxis.
The researchers think that different things may cause SM and cutaneous mastocytosis. SM is often connected to a change in a gene called KIT. About eight out of 10 adults with mastocytosis have this gene change, but children with mastocytosis may or may not have it. This could help explain why cutaneous mastocytosis in children often gets better over time, while mastocytosis in adults usually lasts long-term.
“This study highlights important clinical differences between pediatric and adult mastocytosis,” the researchers said. “Understanding these differences is crucial for age-specific diagnosis, management, and follow-up.”
Sign up here to get the latest news, perspectives, and information about SM sent directly to your inbox. Registration is free and only takes a minute.
