(PROSPECTOR) Screening Study Evaluating the Prevalence of the KIT D816V Mutation in Patients With Systemic Mast Cell Activation
(PROSPECTOR) Screening Study Evaluating the Prevalence of the KIT D816V Mutation in Patients With Systemic Mast Cell Activation
This is a multi-center screening study with the primary objective to determine the prevalence
 of KIT D816V mutation in peripheral blood in patients with evidence of systemic mast cell
 activation (MCA).
Inclusion Criteria:

 -  Presenting with at least one of the three criteria below as evidence of systemic mast
 cell activation:

 1. Involvement of 2 or more organ systems, characterized by skin (pruritus,
 urticaria, flushing and angioedema), cardiovascular (tachycardia, syncope, and
 hypotension), gastrointestinal (diarrhea, nausea, vomiting, and gastrointestinal
 cramping) or respiratory/naso-ocular (wheezing, conjunctival injection, and nasal
 stuffiness) AND serum basal tryptase levels ≥8 ng/ml. One of the organ systems
 must be the cardiovascular system.

 2. Severe, recurrent anaphylaxis (Ring and Messmer grading ≥II) due to Hymenoptera
 sting, regardless of serum basal tryptase levels.

 3. Severe, recurrent anaphylaxis (Ring and Messmer grading ≥II), with cardiovascular
 involvement and documented event-related tryptase elevation fitting the formula
 20% of baseline plus 2 ng/ml evaluated in at least 1 event.

 Exclusion Criteria:

 -  Patient previously diagnosed with any of the following WHO systemic mastocytosis (SM)
 sub-classifications: cutaneous mastocytosis only, indolent SM, smoldering SM, SM with
 associated hematological neoplasm, aggressive SM, mast cell leukemia, mast cell
 sarcoma

 -  Patient diagnosed with other myelo- or lympho-proliferative diseases, e.g.,
 myelodysplastic syndrome, myeloproliferative neoplasm, etc.