Anaphylaxis is a serious allergic reaction that develops rapidly and can cause death. Some patients experience anaphylaxis is association with exercise, a disorder called exercise-induced anaphylaxis. A subset of patients with unexplained anaphylaxis, especially those with hypotension during the anaphylactic episodes, have been shown to have abnormal, clonal populations of a certain cell type, mast cells, in the bone marrow. This has been described in at least one patient with exercise-induced anaphylaxis. The investigators would like review the findings in a group of patients with exercise-induced anaphylaxis who have undergone evaluation for the presence of abnormal, clonal mast cells.
Description: Presence of clonal mast cells in bone marrow as assessed by D816V c-kit mutation or CD25 will be recorded for each participant.
Measure: Number of participants with presence of clonal abnormalities in the bone marrow specimen Time: BaselineDescription: Presence of clonal mast cells in bone marrow as assessed by D816V c-kit mutation or CD25 will be recorded for each participant. The data will be reported as the number of participant with exercise induced anaphylaxis carrying these clonal mast cells in this observational study. Presence of mast cells will be correlated with clinical parameters such as symptoms experienced during anapylaxis.
Measure: Number of participants with presence of clonal abnormalities in the bone marrow specimen Time: BaselineCohort
There is one SNP
Presence of clonal mast cells in bone marrow as assessed by D816V c-kit mutation or CD25 will be recorded for each participant.. Number of participants with presence of clonal abnormalities in the bone marrow specimen. --- D816V ---
Presence of clonal mast cells in bone marrow as assessed by D816V c-kit mutation or CD25 will be recorded for each participant. --- D816V ---