Bradykinin Mediated: Response to a precipitant, including: meds, in particular ACE-I; Can occur soon after initiation or months/years later
Histamine Mediated: Response to a precipitant, including meds (e.g. NSAIDs, Opiates), IV contrast, food, latex, insect bite/stings, other environmental triggers
Hereditary: Rare condition related to C1 inhibitor deficiency
Symptoms
Bradykinin Mediated: acute, focal swelling of lips, upper airway→ acute sob, sometimes intestines→ abd pain; Can occur w/first exposure to meds, or months/years after started; Typically no urticara or itching;
Can be severe and life threatening due to airway issues; Can occur w/anaphylactic rxns→ low bp w/systemic sx
Histamine Mediated: Acute sob, edema, itching, flushing, abdominal pain; Can be severe and life threatening due to airway issues; Can occur w/anaphylactic rxns→ low bp w/systemic sx
Hereditary: Early age onset (sometimes family history); Sob, swelling, abdominal pain, no itching; Often no trigger; Can start in one area of body and spread; Sx last several days; Resolves in hours to days; Can be life threatening due to airway issues
Physical Exam Findings
Bradykinin Mediated: Diffuse swelling of lips/face/head/larynx/tongue if these are primary site; Stridor; Respiratory distress; no urticaria
Histamine Mediated: Redness, stridor, wheezing, hives/urticaria, swelling of face & other body parts, edema often asymmetric and non-pitting
Hereditary: Swelling of face, tongue; Stridor, respiratory distress; No urticaria; Non-pitting edema of face/hands/legs/genitalia/other body parts