Beyond the Rash: Recognizing and Managing Systemic Mastocytosis in Clinical Practice by Madaline Spencer| Published on: Apr 10, 2026

Systemic mastocytosis can present as a simple rash, cutaneous lesions, generalized fatigue, or even spontaneous anaphylaxis, said Dr. Foy. That is one of the greatest challenges in diagnosing the disorder. “We have a bias that allergists deal with these types of problems in general,” he noted. A patient with skin lesions and an unexplained elevation of blood tryptase level (>15 ng/mL) should tip off that the cause is systemic, not an external allergen, and systemic mastocytosis may be the cause. https://checkrare.com/beyond-the-rash-recognizing-and-managing-systemic-mastocytosis-in-clinical-practice/