Insights in Anaphylaxis and Clonal Mast Cell Disorders

Area of Science:

• Hematology
• Immunology
• Allergy

Background:

• Patients with clonal mast cell disorders (MCD) have a higher prevalence of anaphylaxis than the general population.
• Clonal MCD without skin lesions can be underdiagnosed due to subtle symptoms, with anaphylaxis frequently being the initial presentation.
• Mast cell (MC) mediator release in clonal MCD without skin involvement has characteristic clinical features despite a wide symptom spectrum.

Purpose of the Study:

• To review triggers, risk factors, clinical presentation, diagnosis, and management of mast cell activation syndromes (MCAS).
• To emphasize clonal MCAS, including systemic mastocytosis and mono(clonal) MC activation syndromes.

Main Methods:

• Review of clinical features, diagnostic criteria, and management strategies for MCAS.
• Emphasis on diagnostic approaches for clonal MCAS, including bone marrow studies.
• Discussion of triggers and risk factors for anaphylaxis in the context of clonal MCD.

Main Results:

• Anaphylaxis is a common presenting symptom in clonal MCD, particularly when skin lesions are absent.
• Specific clinical patterns characterize MC mediator release episodes in clonal MCD without skin involvement.
• Bone marrow studies are essential for definitive diagnosis and should be performed in specialized centers.

Conclusions:

• Early recognition and diagnosis of clonal MCD are vital, especially in patients presenting with anaphylaxis.
• A comprehensive approach to MCAS management, focusing on clonal disorders, is necessary.
• Reference centers are recommended for accurate diagnosis of clonal mast cell disorders.