Table I.
Etiologic mechanisms of anaphylaxis and their distinguishing characteristics
| Type | Inciting Agents | Cells | Receptors | Mediators |
|---|---|---|---|---|
| IgE-Mediated | Food allergy Insect sting allergy Drug allergy |
Mast cells Basophils |
FcεRI | Histamine PAF |
| IgG-Mediated | Biologicals Drugs Dextrans Aprotinin Transfusions |
Macrophages Neutrophils Basophils |
FcγRIII FcγRI FcγRIV (mouse) FcγRIIA (human) |
PAF Histamine |
| Complement-Mediated | Lipid incipients Micellar drugs Liposome Other nanoparticles Polyethylene glycol Cellulose membranes |
Macrophages Mast cells |
C3aR C5aR |
PAF Histamine |
|
Direct Mast Cell Activation (mechanisms differ for different agents) |
NSAIDs, including aspirin Vancomycin Opiates Local Anesthetics Fluoroquinolone antibiotics Neuromuscular blockers Octreotide Leuprolide |
Mast cells Other myeloid cells |
MRGPRX2 Other receptors |
Cysteinyl leukotrienes Histamine |