Bradykinin and the pathophysiology of angioedema

Angioedema has different causes and different clinical presentations. Some types of angioedema may be mediated by bradykinin. We measured plasma levels of bradykinin-(1-9)nonapeptide by radioimmunoassay after high-performance liquid chromatography in patients with different types of angioedema during acute attacks and/or in remission, i.e. hereditary C1-inhibitor deficiency, angiotensin converting enzyme (ACE) inhibitor treatment, idiopathic non histaminergic and responders to antihistamines. Eleven patients with the deficiency of C1-inhibitor had very high levels of bradykinin during acute attacks of angioedema (18.0-90.0 pM) (normal range 0.2-7.1 pM). In three patients with history of ACE inhibitor-related angioedema, plasma bradykinin was high during ACE inhibitor treatment (62.0, 8.9 and 27.0 pM) and in a fourth patient was 47.0 pM during an acute attack and decreased by 93% to 3.2 pM after withdrawal of the ACE inhibitor. The patient with idiopathic angioedema, during an acute attack involving the right arm, had high levels of bradykinin in the venous blood refluent from the angioedematous arm (20.0 pM) while in the contralateral arm bradykinin levels were normal (6.6 pM), similarly to what we previously observed in cases of brachial angioedema due to C1-inhibitor deficiency. The four patients with angioedema responsive to antihistamines had normal levels of bradykinin even during acute attacks (5.7, 3.4, 4.7 and 1.2 pM). In one of these patients who had a brachial angioedema, bradykinin levels were normal in the venous blood refluent from both arms. Bradykinin is involved in hereditary C1-inhibitor deficiency angioedema, in ACE inhibitor-related angioedema, and in idiopathic non-histaminergic angioedema, while bradykinin is not related to allergen-dependent or idiopathic angioedema that are responsive to antihistamines.

[Urticaria and angioedema]

Urticaria is a common complaint characterized by the eruption of cutaneous wheals, accompanied by redness and itching and in which mast cells are thought to play a central role. Wheals range from a few millimeters to several centimeters in diameter and are usually short lasting, except in case of urticarial vasculitis in which they last longer than 24 hours. Urticaria may occur alone or be associated with angioedema, that can be defined as a deep dermal and subcutaneous edema typically affecting the lips, face, hands, feet, penis or scrotum. Angioedema may also involve the submucosal tissue, and when the swellings occur in the oropharynx they can be alarming and occasionally life-threatening. In many cases the cause of acute urticaria or angioedema may be determined, whilst the pathogenetic and diagnostic aspects of the chronic forms are more complex and variable. The clinical features of, as well as the diagnostic and therapeutic approaches to the different forms of urticaria and angioedema are here reviewed, focusing on chronic idiopathic urticaria.

[Non-allergic angioedema: update]

PURPOSE

Nonallergic isolated angioedema is an uncommon clinical syndrome raising difficult diagnosis and therapeutic problems. Occurrences linked to a C1Inh are the predominant ones and have to be examined as a priority, taking into account the specificity of the associated follow-up.

CURRENT KNOWLEDGE AND KEY POINTS

Diseases with a clinical profile close to hereditary angioneurotic edema, but without C1Inh anomaly, have been described recently. It is in fact family cases, concerning only women, where estrogens seem to play a dominant role. Angioedema's secondary aspects are gathering various pathologies (vasculitis, Gleich's syndrome, angioedema initiated by physical agents). The role played by some drugs must not be forgotten, mainly angiotensin converting enzyme inhibitors, which are at the origin of angiodema in nearly 0.5% of users.

FUTURE PROSPECT AND PROJECTS

Uncontrolled activation of the contact system seems to play a major role in the main part of these angiodemas. The efficiency of the tranexaminic acid (which modulates its activation) is to be taken as evident. The key to the future seems to be the development of plasmin and bradykinin inhibitors.

Drug-induced urticaria and angioedema: pathomechanisms and frequencies in a developing country and in developed countries

A careful drug history should be obtained from all patients with acute or chronic urticaria/angioedema, especially in the elderly. Although strictly comparable data are lacking, drug-induced urticaria appears to be more common in developed countries than in Malaysia, at least in a Hospital setting. Culprit drugs include antibiotics, analgesics and contrast media. Pseudoallergic drug-induced urticaria mimicks true allergic urticaria, but without an evident immunological basis, and is at least as common as the allergic type. In Malaysia, and in many other countries compulsory, ingredient labelling of 'traditional' medicines would do much to reduce the frequency of drug-induced urticaria.

[Snakebite---intoxication by cobra venom]

A private reptile breeder who handled exotic snakes was bitten by a Cobra near his ear. An ambulance was immediately called and the patient was transferred under unstable hemodynamic conditions to the nearest major hospital. During transport the patient had to undergo cardiopulmonary resuscitation. In the hospital, his status again deteriorated and he was intubated at a Glasgow coma scale of 5 and vasoactive medications were given. The patient was transferred by helicopter to a university hospital, where several doses of antivenom were given. After 4 days of deep coma the patient regained consciousness and spontaneous respiration and was extubated. Around the location of the bite wound angioedema and local necrosis developed. Surgical treatment of the wound was not necessary and 8 days after the incident the patient was fully recovered and was discharged from the hospital.

Urticaria and angioedema from cyclooxygenase-2 inhibitors

Cyclooxygenase-2 (COX-2) inhibitors celecoxib and rofecoxib have generally been well tolerated. It has been unclear if specific COX-2 inhibitors would cross react with acetylsalicylic acid and typical nonsteroidal antiinflammatory drugs to cause urticaria or angioedema. There are no reports in the literature of hives or angioedema resulting from their use. We describe 3 patients who developed urticaria and/or angioedema from COX-2 inhibitors. With the increasing use of COX-2 inhibitors, one needs to be aware of these side effects and of possible cross reactivity between celecoxib and rofecoxib.

MR imaging and thermography of facial angioedema: a case report

Magnetic resonance imaging and thermography were performed in a 67-year-old man with idiopathic facial angioedema. Thermography suggested decreased heat emission in the region of the angioedema. Magnetic resonance imaging revealed diffuse high intensity in the subcutaneous interstitial tissue and dilated veins on T2-weighted images. Marked contrast enhancement was noted in the subcutaneous tissue on postcontrast T1-weighted images.

Natural course of physical and chronic urticaria and angioedema in 220 patients

BACKGROUND

Information about spontaneous remission of chronic urticaria is limited.

OBJECTIVE

To investigate the natural course of urticaria, we followed up 220 adults in a prospective study.

METHODS

Patients were followed up for 1 to 3 years to evaluate interventions, to detect latent causes, and to study the natural course of urticaria. The diagnosis was made by detailed history-taking as well as laboratory and provocation tests.

RESULTS

Thirty-five percent of all patients were free of symptoms after 1 year. In 28.9% of patients, symptoms had decreased. Spontaneous remission occurred in 47.4% of the patients in whom no cause of their urticaria and/or angioedema could be identified and in only 16.4% of the patients with physical urticaria. A cause could be identified in 53.1% of the patients. Thirty-six percent of the patients had idiopathic urticaria. Chronic idiopathic urticaria combined with physical urticaria occurred in 10.9%.

CONCLUSION

In general, the prognosis for spontaneous remission is reasonable, with the exception of the subgroup (33.2%) with physical urticaria.

Hereditary angioedema with a de novo mutation of exon 8 in the C1 inhibitor gene showing recurrent edema of the hands around the peripheral joints: importance for the differential diagnosis of joint swelling

We describe a patient with hereditary angioedema (HAE), showing recurrent edema around the peripheral joints. Her symptoms began at the age of 18 with hand swelling distal to the wrist joints. Until she was referred to our hospital 3 years after her initial symptoms, she was still undiagnosed, although she was suspected of having rheumatoid arthritis. Laboratory examination showed reduced levels of CH50 and C4 with normal C3 levels. The C1 inhibitor (C1-INH) was decreased to 5 mg/ml, with remarkably reduced activity. Although these findings were compatible with a diagnosis of HAE, there were no episodes of skin edema in her family. To establish the diagnosis, we carried out DNA analysis of the C1-INH gene, which revealed a newly identified de novo mutation of G to A at nucleotide 16869 in exon 8. As described in this patient, localized edema around the peripheral joints may be the only manifestation of HAE. HAE should therefore be taken into consideration for the differential diagnosis of joint swelling.

Nonepisodic angioedema associated with eosinophilia: report of 4 cases and review of 33 young female patients reported in Japan

BACKGROUND

In 1984, Gleich et al. described 4 patients with episodic angioedema associated with eosinophilia (EAE), which was characterized by recurrent episodes of angioedema and urticaria, eosinophilia, elevated serum IgM, fever, increased body weight and a benign course without involvement of the internal organs demonstrating that it was a clinical entity distinct from the hypereosinophilic syndrome. Thereafter, 37 cases of EAE have been reported in Japan, 33 cases of which, although similar, had a different evolution from classical EAE.

OBJECTIVE

To describe 4 cases and review the cases of angioedema associated with eosinophilia reported in Japan.

RESULTS

Four Japanese female patients had persistent angioedema mainly involving the hands and lower legs, and eosinophilia which resolved within a few months. The review of the 37 cases of EAE in the Japanese literature demonstrated that in 33 cases, there were common characteristics which differed from EAE. These included: (1) the absence of recurrent attacks; (2) the predominance of young females (20-37 years, with a mean of 26 years); (3) the localization of the angioedema to the extremities; (4) the absence of increase in the serum IgM level, and (5) the effectiveness of low-dose prednisone or even the occurrence of spontaneous remission.

CONCLUSION

We propose that persistent angioedema with eosinophilia can be classified into 2 types, i.e. one being an episodic (recurrent) type as reported by Gleich and a nonepisodic type as our 4 cases and others found in the Japanese literature.

Management of children with hereditary angioedema: a report of two cases

Dentists must take extreme care in treating patients with Hereditary Angioedema (HAE). Physical trauma, emotional stress, or anxiety during dental treatment could lead to an acute attack that may lead to a laryngeal obstruction. This article reviews clinical signs and symptoms, disease classification, pathophysiology, and treatment recommendations for HAE. Management of 2 patients with HAE is also presented.

Acquired angioedema with C1 inhibitor deficiency: is the distinction between type I and type II still relevant?

BACKGROUND

Acquired angioedemas are divided into type I associated with lymphoproliferation and type II caused by anti-C1-inhibitor antibodies. Recent reports have suggested that this distinction is not so clear-cut, mainly because of the presence of antibodies against the C1 inhibitor in some cases belonging to the type I group. We report herein 2 additional cases of acquired angioedema with anti-C1-inhibitor antibody.

MATERIAL AND METHODS

One man and 1 woman had had acquired angioedema for several years. In the man, a monoclonal component had been detected several years before the present study. In the second patient, a monoclonal component was detected during the study. The following data were studied on successive blood samples collected during angioedema manifestations: complement component levels, functional activity of the classical pathway, functional and antigenic C1 inhibitor doses, ELISA test to detect autoantibodies to C1 inhibitor and Western blot analysis of the C1 inhibitor.

RESULTS

In both patients, CH50 and C4 activities were decreased, and an autoantibody to C1 inhibitor was detected. In 1 case, the antibody appeared after the monoclonal component; in the second case, it appeared before and belonged to a different immunoglobulin class.

CONCLUSION

Our data suggest that the distinction between type I and type II acquired angioedema is no longer valid because of overlapping in some cases.

Transient myocardial dysfunction associated with angiotensin-converting enzyme inhibitor-induced angioedema: recognition by serial echocardiographic studies

We report a case of a 58-year-old woman who had angiotensin converting enzyme inhibitor-induced angioedema after she underwent a biopsy of a hypopharyngeal mass. The angioedema was associated with severe transient myocardial dysfunction documented on echocardiography. She did not have anaphylaxis or coronary artery disease. To our knowledge this is the first reported case of transient myocardial dysfunction in the setting of angiotensin converting enzyme inhibitor-induced angioedema without anaphylaxis.

Angioedema due to losartan

OBJECTIVE

To report a case of angioedema associated with the angiotensin II receptor antagonist losartan.

CASE SUMMARY

A 62-year-old African-American woman was admitted to the hospital for acute renal failure and uncontrolled hypertension. After attempting blood pressure control with three different agents, captopril was combined with metoprolol. The patient noted swelling of the lips combined with shortness of breath after four days of captopril. Losartan was substituted for captopril, which then produced similar swelling of the lips (without shortness of breath) after only one dose. These symptoms resolved after discontinuation of losartan and administration of antihistamines.

DISCUSSION

Losartan, like other angiotensin II receptor antagonists, blocks the action of angiotensin II at the receptor level. Five published case reports involved patients with a prior history of intolerance to the angiotensin-converting enzyme inhibitors. Two published case reports of similar reactions also occurred in patients with renal compromise. The mechanism for this reaction from losartan is not known, but may not be due to bradykinin excess.

CONCLUSIONS

Clinicians should be aware that angiotensin receptor antagonists may not be safe alternatives in patients who have a history of angioedema secondary to the angiotensin-converting enzyme inhibitors.

Losartan-induced angioedema

OBJECTIVE

To report a case of angioedema associated with losartan administration.

CASE SUMMARY

A 45-year-old white man with a history of hypertension and gout was treated with losartan/hydrochlorothiazide, allopurinol, and colchicine. The patient experienced two episodes of angioedema within a 10-hour period. On both occasions the symptoms resolved after treatment.

DISCUSSION

Angiotensin-converting enzyme (ACE) inhibitors are associated with a relatively high incidence of angioedema. The incidence of angioedema secondary to losartan, an angiotensin II receptor antagonist, is unknown. The patient reported in this case differs significantly from the two cases reported in the literature because he had normal renal function, no previous exposure to ACE inhibitors, the reaction was of late onset, and the symptoms recurred.

CONCLUSIONS

This case suggests that losartan can induce late-onset angioedema in patients with normal renal function and that the reaction can recur after initial resolution of the symptoms.

Hereditary angioedema with gastrointestinal involvement: endoscopic appearance

We present the first reported case of hereditary angioedema (HAE) with gastric involvement to be successfully evaluated by endoscopy both during and after an attack. A 31-year-old man who had a family history of angioedema was admitted to our hospital with complaints of abdominal pain and swelling of extremities. Computed tomography scan and endoscopy carried out during this attack revealed transient gastrointestinal wall edema which, along with decreased levels of serum C4 and C1 inhibitor, confirmed the diagnosis of HAE with gastrointestinal involvement. During the attack, the gastric mucosa was erythematous and edematous, and parts of its surface bulged into the gastric lumen, resembling a submucosal tumor, as a result of massive submucosal edema. During the healing process, a number of small nodules and raised erosions developed over the entire gastric mucosal surface after healing of prominent gastric edema. Within 55 days, the gastric mucosa had returned to normal. The endoscopic findings for the stomach in HAE have not, to our knowledge, been previously described.

[Impossibility of intubation due to angioedema secondary to an angiotensin-converting enzyme inhibitor]

Angioedema secondary to treatment of one year's duration with angiotensin converting enzyme inhibitor (ACEI) (lisinopril) in a 56-year-old man scheduled for elective cardiac surgery led unexpectedly to impossible intubation. Surgical access (tracheostomy) was required when airway control was threatened. We review the clinical course, etiology and treatment of angioedema secondary to ACEI therapy. This is a life threatening complication which, though rare, is becoming increasingly frequent with increased use of such drugs.

Coincidence of hereditary angioedema (HAE) with Crohn's disease

A patient with two diseases, based presumably on different immunopathological mechanisms, hereditary angioedema (HAE) and Crohn's disease, was followed for 8 years. For more than three years of this observation period, detailed laboratory data were also available and could be analyzed. Both diseases had severe courses requiring chronic treatment with danazol and sulfasalazine, respectively. During exacerbation of Crohn's disease, the levels of C4 was found to be significantly lower than during the periods free of symptoms of both diseases. This drop was probably due to an impaired C1-inhibitor activity. HAE attacks and acute exacerbation of Crohn's disease never occurred simultaneously. This finding may be a mere chance but may also indicate that the different immunopathological processes underlying HAE and Crohn's disease influence each other.

Regulation of C1 inhibitor synthesis

The primary biologic roles of C1 inhibitor (C1-INH) are the regulation of activation of the classical complement pathway and of the contact system of kinin formation. Heterozygosity for deficiency or dysfunction of C1-INH results in hereditary angioedema (HAE). This deficiency results in loss of homeostasis with unregulated complement and contact system activation. Due to the consequent C1-INH consumption, plasma levels of C1-INH in patients with HAE are decreased below 50% of normal. In addition, diminished synthesis contributes to the lowered levels in some patients. The hepatocyte is the primary source of C1-INH, although a number of other cell types, including peripheral blood monocytes, microglial cells, fibroblasts, endothelial cells, the placenta, and megakaryocytes also synthesize and secrete the protein both in vivo and in vitro. Interferon-gamma and alpha (IFN), colony stimulating factor-1, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) all induce C1-INH synthesis in a variety of cell types. The IFN-response elements in the 5'-flanking region and in the first intron have been partially characterized, as have several of the promoter elements that direct basal transcription of the gene. However, although androgen therapy, in vivo, results in an increase in C1-INH plasma levels, a direct effect of androgens on C1-INH synthesis has not been convincingly demonstrated. Although the C1-INH gene contains a potential glucocorticoid/androgen response element, this element does not appear to respond to androgen. Continued analysis of the transcriptional regulation of the C1-INH gene may lead to new approaches to therapy of HAE.

[Recurrent angioedema with gastroenteritis in blood and tissue eosinophilia]

A 23-year-old patient suffered from episodic angioedema of the face and neck, accompanied by diarrhea and abdominal pain. Additionally, the patient had bronchial asthma, recurrent nasal polyps and allergic rhinoconjunctivitis. Blood examination revealed leucocytosis with eosinophilia. Histological studies showed eosinophilic infiltrates in the skin and the gastrointestinal mucosa. Allergic food reactions and parasites were ruled out. With systemic corticosteroid treatment, the clinical symptoms and the eosinophilia disappeared. This case shows some parallels to previously described syndromes (eosinophilic gastroenteritis, Samter's syndrome, episodic angioedema with eosinophilia), but to the best of our knowledge this combination of symptoms has not yet been reported.