The Mast Cell Connect Registry is a voluntary, observational database that will capture demographic, socioeconomic, and disease information directly from patients with mastocytosis via a secure web-based tool. No experimental intervention is involved.

Mastocytosis is an extremely rare and heterogeneous spectrum of diseases characterized by the buildup of genetically altered mast cells. Patients experience a wide range of symptoms and in some cases, mast cell buildup can lead to organ dysfunction and failure. Current treatments address disease symptoms and not the underlying cause. To facilitate the development of new therapies for mastocytosis, it is important for the community to support clinical trials and to document the impact of the disease, including disease natural history and the impact on patients, in a systematic way. Mast Cell Connect is a web-based registry that allows mastocytosis patients and caregivers to enter information about the experience of the patient living with mastocytosis directly into an online data collection tool.

The Mast Cell Connect Registry allows mastocytosis patients and caregivers to enter information about the experience of the patient living with mastocytosis directly into a web-based data collection tool. Two forms of data will be collected: responses to surveys administered on the web-based portal, and de-identified data curated from medical reports uploaded by patients or their caregivers.

Inclusion Criteria:

• Any patient with a diagnosis of mastocytosis, including systemic mastocytosis and cutaneous mastocytosis and any subtypes of these diseases, who is willing and able to provide written online informed consent

Exclusion Criteria:

• None

Patients with a diagnosis of mastocytosis, including systemic mastocytosis and cutaneous mastocytosis and any subtypes of these diseases.