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Angioedema
Essentials
- May occur as an independent symptom or be associated with urticaria Hives (Urticaria).
 - Angioedema without urticaria is usually either associated with an underlying drug reaction or idiopathic.
 - The treatment is symptomatic. If the triggering factor can be identified, it should be avoided.
 - It is important to identify laryngeal oedema and patients requiring acute hospital treatment.
 - Angioedema may be an anaphylactic symptom Anaphylaxis.
 
Clinical picture and symptoms
- Sudden-onset circumscribed oedema of deeper skin structures and/or mucosa.
 - The superficial skin is usually normal; there may be erythema.
 - The duration of symptoms varies from less than a day to even up to 5 days.
 - Typical sites include the lips, tongue, eyelids, face (picture 2); may also occur on the limbs (e.g. backs of the hands), trunk or genital area (such as the testes).
 - The oedema feels doughy on palpation, and there is no pitting.
 - There is usually tingling and pain, less often itching. Oedema may occur without any other symptoms.
 - There may be urticaria.
 - Oedema in the upper respiratory tract (laryngeal oedema) may lead to sudden respiratory insufficiency and may be fatal.
 - Symptoms of laryngeal oedema include a sensation of tight throat, voice change and respiratory difficulty.
 - During the attack, there may be gastrointestinal oedema and other gastrointestinal symptoms; these may rarely be the sole symptoms of angioedema.
 
Causes
- Drugs (ACE inhibitors, ARBs, non-steroidal anti-inflammatory analgesics, possibly also other drugs)
 - Association with urticaria, such as acute urticaria triggered by infections Hives (Urticaria)
 - Physical urticarias (pressure, vibration, heat or cold) Hives (Urticaria)
 - Idiopathic (e.g. autoimmune angioedema)
                    
- About 10% of chronic urticarias present only as paroxysmal angioedema without wheals.
 
                   - Allergic reactions: food allergies Food Allergy in Adults (oral allergy syndrome), allergy to Hymenoptera, latex allergy
 - Angioedema may be the first symptom of an anaphylactic reaction Anaphylaxis.
 - Hereditary angioedema Hereditary Angioedema (HAE) and ACE Inhibitor-Induced Angioedema; very rare, with a prevalence of about 1:50 000
 
Diagnosis
- The diagnosis is based on clinical findings.
 - It is important to exclude angioedema of the upper respiratory tract (e.g. laryngeal oedema) and to identify patients requiring emergency hospital treatment (with intubation available during treatment and monitoring).
 - Clinical examination
                    
- Pharyngeal and oral mucosa (uvular oedema, mucosal oedema?); palpation of the neck
 - Auscultation of the neck; inspiratory stridor?
 - Respiratory rate (more than 25/min usually abnormal); does dyspnoea prevent speaking?
 - Pulse oximetry (< 92% clearly abnormal)
 - Exclusion of anaphylactic reaction: blood pressure, lung auscultation (bronchial obstruction?)
 - Hot erythema, ulcers or symptoms of infection do not indicate angioedema.
 
                   - Patient history
                    
- Development of the disease, medication, allergies, food, family history
 - Is there a temporal association with any drug (new drug started before the onset of the symptoms)?
 
                   - Angioedema due to ACE inhibitors or ARBs Hereditary Angioedema (HAE) and ACE Inhibitor-Induced Angioedema may have a sudden onset even after long-term use. Symptoms may continue for 1-6 months after withdrawing the medication.
 
Differential diagnosis
- Erysipelas or cellulitis (glowing, hot erythema, fever, chills) Erysipelas; recurring erysipelas may also occur, for instance in the genital area
                    
- Incipient shingles (pain, erythema in the area of the dermatome, precisely restricted to one side of the median line, unilateral) Shingles (Herpes Zoster)
 
                   - Acute allergic contact dermatitis Allergic Contact Dermatitis (itching, papules and vesicles on the skin, eczematous clinical picture, restricted to area of exposure to contact allergen)
 - Local reaction to insect sting or bite Insect Stings and Bites (history of insect sting or bite, sting or bite mark and petechia in the centre of the oedema)
 - Other conditions causing oedema
                    
- Oedema caused by hypoproteinaemia (e.g. nephrotic syndrome, enteropathies)
 - Myxoedema (in most cases associated with hypothyroidism)
 - Factors obstructing veins and/or lymph vessels (e.g. compression of superior vena cava)
 - Lymphoedemas
 - Macroglossia (acromegaly, amyloidosis, hypothyroidism, Melkersson-Rosenthal syndrome)
 
                   - Angioedema associated with ACE inhibitor therapy or, more rarely, with other pharmacotherapy Hereditary Angioedema (HAE) and ACE Inhibitor-Induced Angioedema
 - Very rare hereditary angioedema (HAE) Hereditary Angioedema (HAE) and ACE Inhibitor-Induced Angioedema.
 
Workup
- Inflammation parameters (CRP, basic blood count with platelet count), as necessary for differential diagnosis, to exclude infection
 - In the case of recurring attacks (can be performed in the interim):
                    
- Targeted examination for IgE-mediated allergy (specific IgE antibodies, prick tests) if an allergic reaction (food allergy, for example) is suspected
 - If an autoimmune disease is suspected, thyroid tests TSH, free T4, TPO antibodies, as necessary, or other targeted examinations
 - Serum C1 esterase inhibitor, C1 esterase inhibitor biological activity, C3 and C4 (if hereditary angioedema is suspected)
 
                   
Treatment
- In patients who are in a good general condition and have no risk factors or signs of upper respiratory tract obstruction, monitoring and symptomatic treatment, as necessary, may be sufficient.
 - The triggering factor (e.g. drug) should be withdrawn, as far as possible, and a follow-up visit arranged, as necessary
                    
- If angioedema is suspected of being caused by an ACE inhibitor or ARB, this should be replaced by another antihypertensive drug, such as a calcium-channel blocker and/or diuretic. If the ACE inhibitor has been paused for 6 months and the patient has remained asymptomatic, an ARB can be tried based on case-by-case judgement, if this is necessary for the treatment.
 
                   - An antihistamine at 1-4 times the normal dose (1-2 tablets in the morning and in the evening, with sic! written in the prescription) for 1-2 weeks at a time
                    
- This is effective for urticaria (histaminergic angioedema), in particular.
 - However, antihistamines are often ineffective (so-called non-histaminergic angioedema, usually bradykinin-mediated).
 
                   - If the oedema is severe and disturbing, adults can be given oral glucocorticoids, such as prednisolone at a dose of 30-40 mg once daily (0.5 mg/kg in courses of 1-3 days), for example.
 - In some cases, tranexamic acid may help, given at doses of 1-1.5 g 2-3 times daily for a few days (until angioedema subsides).
                    
                  
 - Analgesics, as necessary (if there is no sign of a reaction triggered by non-steroidal anti-inflammatory analgesics)
 - Topical application of cold or a cooling gel may alleviate the symptoms.
 - For treatment of hereditary angioedema (HAE) and ACE inhibitor-induced angioedema, see Hereditary Angioedema (HAE) and ACE Inhibitor-Induced Angioedema.
 
If there are signs of upper respiratory oedema
- Emergency hospital care (transportation with intubation available); further treatment and monitoring in a unit with intubation and tracheostomy available.
 - Adrenaline will reduce the oedema: for adults 0.3-0.5 mg i.m. (0.01 mg/kg if patient weighs < 50 kg), repeated every 10-20 min, as necessary. See Anaphylaxis Anaphylaxis.
 - For patients with hypoxaemia symptomatic treatment with oxygen
 - Glucocorticoid i.v., such as a 40-80 mg bolus of i.v. methylprednisolone
 - I.v. fluid administration (Ringer or NaCl)
 - Causal treatment, as far as possible (such as withdrawal of ACE inhibitor)
 - For life-threatening ACE inhibitor-induced angioedema, in addition to the aforementioned treatments, also spesific therapies for HAE (e.g. C1 inhibitors) have been used.
 - For hereditary angioedema, specific treatment Hereditary Angioedema (HAE) and ACE Inhibitor-Induced Angioedema
 
Recurring angioedema
- Avoid the cause (drugs, allergies) as far as possible
 - In idiopathic angioedema, it is worth trying regular prophylactic medication with an antihistamine. If the treatment does not work, it is suggestive of so-called non-histaminergic, i.e. usually bradykinin-mediated, angioedema.
 - Prophylactic antihistamines: 1-4 times the normal dose (1-2 tablets every morning and evening), with the patient titrating the dose according to the response and symptoms
 - For attacks, a glucocorticoid at doses of, for example, 30-40 mg once daily (0.5 mg/kg in courses of 1-3 days) and an oral antihistamine
 - In severe cases, the patient may be prescribed a disposable adrenaline syringe for use as needed. Instructions for its use must be given to the patient and the family.
 - Tranexamic acid may also be useful for attacks.
 
Specialist consultation
- For patients with respiratory tract obstruction, emergency hospital care and monitoring (preparedness for intubation and tracheostomy)
 - Specialized care should be consulted if symptoms are persistent or severe (unit with special expertise in the treatment and diagnosis of angioedema)
 - An allergologist should be consulted if allergy is suspected but its cause remains unclear.
 - For hereditary angioedema, monitoring and treatment in a specialized care unit specializing in familiar angioedema
 
References
- Powell RJ, Leech SC, Till S et al. BSACI guideline for the management of chronic urticaria and angioedema. Clin Exp Allergy 2015;45(3):547-65. [PubMed].
 - Moellman JJ, Bernstein JA, Lindsell C et al. A consensus parameter for the evaluation and management of angioedema in the emergency department. Acad Emerg Med 2014;21(4):469-84. [PubMed]
 - Sánchez-Borges M, Asero R, Ansotegui IJ et al. Diagnosis and treatment of urticaria and angioedema: a worldwide perspective. World Allergy Organ J 2012;5(11):125-47. [PubMed]
 - Hébert J, Boursiquot JN, Chapdelaine H et al. Bradykinin-induced angioedema in the emergency department. Int J Emerg Med 2022;15(1):15. [PubMed]
 - Caballero T, Baeza ML, Cabañas R et al. Consensus statement on the diagnosis, management, and treatment of angioedema mediated by bradykinin. Part II. Treatment, follow-up, and special situations. J Investig Allergol Clin Immunol 2011;21(6):422-41; quiz 442-3. [PubMed]
 - LoVerde D, Files DC, Krishnaswamy G. Angioedema. Crit Care Med 2017;45(4):725-735. [PubMed]
 - Stoldt J, Cox C, Matusz E. Tranexamic acid use in the setting of ACE inhibitor induced angioedema. Am J Emerg Med 2022;(55):230.e3-230.e4. [PubMed]
 - Zuberbier T, Aberer W, Asero R et al. The EAACI/GA²LEN/EDF/WAO guideline for the definition, classification, diagnosis and management of urticaria. Allergy 2018;73(7):1393-1414. [PubMed]
 - Bernstein JA, Cremonesi P, Hoffmann TK et al. Angioedema in the emergency department: a practical guide to differential diagnosis and management. Int J Emerg Med 2017;10(1):15. [PubMed]
 - Riha HM, Summers BB, Rivera JV et al. Novel Therapies for Angiotensin-Converting Enzyme Inhibitor-Induced Angioedema: A Systematic Review of Current Evidence. J Emerg Med 2017;53(5):662-679. [PubMed]
 - Lawlor CM, Ananth A, Barton BM et al. Pharmacotherapy for Angiotensin-Converting Enzyme Inhibitor-Induced Angioedema: A Systematic Review. Otolaryngol Head Neck Surg 2018;158(2):232-239. [PubMed]
 - Zuberbier T, Abdul Latiff AH, Abuzakouk M et al. The international EAACI/GA²LEN/EuroGuiDerm/APAAACI guideline for the definition, classification, diagnosis, and management of urticaria. Allergy 2021 Sep 18. doi: 10.1111/all.15090 [PubMed]
 - Jeon J, Lee YJ, Lee SY. Effect of icatibant on angiotensin-converting enzyme inhibitor-induced angioedema: A meta-analysis of randomized controlled trials. J Clin Pharm Ther 2019;44(5):685-692. [PubMed]