There are no known causes, but the condition appears to be inherited in some patients. Symptoms of<unk>  are caused by excessive chemical mediators inappropriately released by<unk> <unk> s. Mediators include leukotrienes, histamines, prostaglandin, and tryptase. The condition may be mild until exacerbated by stressful life events, or symptoms may develop and slowly trend worse with time.
Mast cell activation syndrome
CREST syndrome
Cytokine release syndrome
MOMO syndrome
SUNCT syndrome
Macrophage activation syndrome
Systemic inflammatory response syndrome
OSLAM syndrome