The Angiotensin-Converting-Enzyme-Induced Angioedema

Pharmacovigilance study of the association between dipeptidyl peptidase-4 inhibitors and angioedema using the FDA Adverse Event Reporting System (FAERS)

Dipeptidyl peptidase-4 (DPP-4) plays a minor role in degrading vasoactive peptides that cause angioedema when angiotensin-converting enzyme (ACE) is present and fully functional. This study investigated the association between DPP-4 inhibitors (DPP-4Is) and angioedema, including cases where the concomitant use of ACE inhibitors (ACEIs) was absent. We obtained data from the US Food and Drug Administration Adverse Event Reporting System and performed a disproportionality analysis, using the reporting odds ratio (ROR) and information component (IC) for signal detection in patients aged ≥ 40 years, stratified by age group and sex. No signal was detected for DPP-4Is when the entire dataset was analyzed. However, a signal was detected for the entire female subset group, the three stratified female groups aged ≥ 60 years, and males in their 40 s. After excluding the data of concomitant ACEI users, most ROR and IC values were lower and significant only for females in their 60 s and males aged ≥ 80 years. Regarding individual DPP-4Is signals, those detected for saxagliptin and sitagliptin in some age groups disappeared after excluding the data of ACEI users. Notably, linagliptin was the only DPP-4I where signals were detected in most female groups, regardless of age and without concomitant ACEI use. Our findings suggest that some DPP-4Is were associated with a higher reporting of angioedema as per age and sex, even in the absence of concomitant ACEI use.

Molecular Genetic Screening in Patients With ACE Inhibitor/Angiotensin Receptor Blocker-Induced Angioedema to Explore the Role of Hereditary Angioedema Genes

Angioedema is a relatively rare but potentially life-threatening adverse reaction to angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARBs). As with hereditary forms of angioedema (HAE), this adverse reaction is mediated by bradykinin. Research suggests that ACEi/ARB-induced angioedema has a multifactorial etiology. In addition, recent case reports suggest that some ACEi/ARB-induced angioedema patients may carry pathogenic HAE variants. The aim of the present study was to investigate the possible association between ACEi/ARB-induced angioedema and HAE genes via systematic molecular genetic screening in a large cohort of ACEi/ARB-induced angioedema cases. Targeted re-sequencing of five HAE-associated genes (SERPING1, F12, PLG, ANGPT1, and KNG1) was performed in 212 ACEi/ARB-induced angioedema patients recruited in Germany/Austria, Sweden, and Denmark, and in 352 controls from a German cohort. Among patients, none of the identified variants represented a known pathogenic variant for HAE. Moreover, no significant association with ACEi/ARB-induced angioedema was found for any of the identified common [minor allele frequency (MAF) >5%] or rare (MAF < 5%) variants. However, several non-significant trends suggestive of possible protective effects were observed. The lowest p-value for an individual variant was found in PLG (rs4252129, p.R523W, p = 0.057, p.adjust > 0.999, Fisher’s exact test). Variant p.R523W was found exclusively in controls and has previously been associated with decreased levels of plasminogen, a precursor of plasmin which is part of a pathway directly involved in bradykinin production. In addition, rare, potentially functional variants (MAF < 5%, Phred-scaled combined annotation dependent depletion score >10) showed a nominally significant enrichment in controls both: 1) across all five genes; and 2) in the F12 gene alone. However, these results did not withstand correction for multiple testing. In conclusion, our results suggest that HAE-associated mutations are, at best, a rare cause of ACEi/ARB-induced angioedema. Furthermore, we were unable to identify a significant association between ACEi/ARB-induced angioedema and other variants in the investigated genes. Further studies with larger sample sizes are warranted to draw more definite conclusions concerning variants with limited effect sizes, including protective variants.

Rare Diseases of the Oral Cavity, Neck, and Pharynx

Diseases occurring with an incidence of less than 1-10 cases per 10 000 individuals are considered as rare. Currently, between 5 000 and 8 000 rare or orphan diseases are known, every year about 250 rare diseases are newly described. Many of those pathologies concern the head and neck area. In many cases, a long time is required to diagnose an orphan disease. The lives of patients who are affected by those diseases are often determined by medical consultations and inpatient stays. Most orphan diseases are of genetic origin and cannot be cured despite medical progress. However, during the last years, the perception of and the knowledge about rare diseases has increased also due to the fact that publicly available databases have been created and self-help groups have been established which foster the autonomy of affected people. Only recently, innovative technical progress in the field of biogenetics allows individually characterizing the genetic origin of rare diseases in single patients. Based on this, it should be possible in the near future to elaborate tailored treatment concepts for patients suffering from rare diseases in the sense of translational and personalized medicine. This article deals with orphan diseases of the lip, oral cavity, pharynx, and cervical soft tissues depicting these developments. The readers will be provided with a compact overview about selected diseases of these anatomical regions. References to further information for medical staff and affected patients support deeper knowledge and lead to the current state of knowledge in this highly dynamic field.

Angioedemas associated with renin-angiotensin system blocking drugs: Comparative analysis of spontaneous adverse drug reaction reports

INTRODUCTION

Angioedema is a subcutaneous swelling typically affecting the face, larynx or pharynx. It is a known adverse drug reaction (ADR) of ACE inhibitors (ACEi), angiotensin-II-receptor blockers (ARBs) and aliskiren (renin inhibitor). Several studies have reported pathophysiological mechanisms and risk factors of ACEi-associated angioedemas, whereas little is known for ARBs and aliskiren. The aim of the study was to analyze comparatively ACEi versus ARBs and aliskiren angioedema reports contained in the European ADR database EudraVigilance with regard to reported risk factors and clinical phenotypes.

METHODS

All spontaneous angioedema reports received between 01/2010-06/2017 reporting either an ACEi, ARB, or aliskiren as "suspected/interacting" drug were identified using the Standardized MedDRA Query "angioedema (narrow)". In order to perform a comparative analysis, odds ratios (ORs) were calculated for angioedema reports of ACEi (n = 3.194) versus ARBs (n = 687) and aliskiren (n = 162).

RESULTS

More patients with a history of allergy were included in angioedema reports of ARBs (6.8%) and aliskiren (13.6%) versus ACEi (4.3%). "Urticaria" as an ADR was reported more frequently in angioedema reports of ARBs (18.5%) and aliskiren (9.0%) versus ACEi (5.0%). ACEi-associated angioedemas were more often designated as "life-threatening" compared to ARBs (OR 2.2 [1.6-2.9]) and aliskiren-associated angioedemas (OR 14.2 (3.5-57.4). Concomitant therapy with mTOR inhibitors (OR 4.3 [1.0-17.9]) and fibrinolytics (OR 7.8 [1.1-57.2]) was reported more often in ACEi versus ARBs angioedema reports.

CONCLUSION

The reported clinical phenotypes differed between ACEi versus ARBs and aliskiren angioedema reports. Differences between the patient populations as observed in our study or differences with regard to underlying pathomechanisms could account for this finding. Due to the methodological limitations of spontaneous reporting systems, we cannot draw a firm conclusion in this regard. Hence, further research is necessary to confirm our observation and elucidate the underyling causes.

Genome-wide association study of angioedema induced by angiotensin-converting enzyme inhibitor and angiotensin receptor blocker treatment

Angioedema in the mouth or upper airways is a feared adverse reaction to angiotensin-converting enzyme inhibitor (ACEi) and angiotensin receptor blocker (ARB) treatment, which is used for hypertension, heart failure and diabetes complications. This candidate gene and genome-wide association study aimed to identify genetic variants predisposing to angioedema induced by these drugs. The discovery cohort consisted of 173 cases and 4890 controls recruited in Sweden. In the candidate gene analysis, ETV6, BDKRB2, MME, and PRKCQ were nominally associated with angioedema (p < 0.05), but did not pass Bonferroni correction for multiple testing (p < 2.89 × 10⁻⁵). In the genome-wide analysis, intronic variants in the calcium-activated potassium channel subunit alpha-1 (KCNMA1) gene on chromosome 10 were significantly associated with angioedema (p < 5 × 10⁻⁸). Whilst the top KCNMA1 hit was not significant in the replication cohort (413 cases and 599 ACEi-exposed controls from the US and Northern Europe), a meta-analysis of the replication and discovery cohorts (in total 586 cases and 1944 ACEi-exposed controls) revealed that each variant allele increased the odds of experiencing angioedema 1.62 times (95% confidence interval 1.05–2.50, p = 0.030). Associated KCNMA1 variants are not known to be functional, but are in linkage disequilibrium with variants in transcription factor binding sites active in relevant tissues. In summary, our data suggest that common variation in KCNMA1 is associated with risk of angioedema induced by ACEi or ARB treatment. Future whole exome or genome sequencing studies will show whether rare variants in KCNMA1 or other genes contribute to the risk of ACEi- and ARB-induced angioedema.

ACE inhibitor-mediated angioedema

Angioedema (AE) occurring during ACE inhibitor therapy (ACEi-AE) is a rare complication involving between 0.1 and 0.7% of treated patients. AE can also complicate other therapeutic regimens that block the renin-angiotensin aldosterone system. Other drugs, such as immune suppressors, some type of antidiabetics or calcium antagonists, can increase the likelihood of ACEi-AE when associated to ACEi. There is a clear ethnic predisposition, since African-Americans or Hispanics show a higher prevalence of this condition compared to Caucasians. At least in African-Americans the genetic predisposition accounts for a general higher prevalence of AE, independently from the cause. People that experience ACEi-AE may have some recurrence when they are switched to an angiotensin-receptor blocker (ARB); however, epidemiological studies on large cohorts have shown that angiotensin receptor blockers (ARB) do not increase the likelihood of AE compared to other antihypertensives. Clinical manifestations consist of edema of face, lips, tongue, uvula and upper airways, requiring intubation or tracheotomy in severe cases. Attacks last for 48-72 h and require hospital admission in most cases. Intestinal involvement with sub-occlusive symptoms has also been reported. The pathogenesis of ACEi-AE depends mainly on a reduced catabolism and accumulation of bradykinin, which is normally metabolized by ACE. Genetic studies have shown that some single nucleotide polymorphisms at genes encoding relevant molecules for bradykinin metabolism and action may be involved in ACEi-AE, giving a basis for the ethnic predisposition. Treatment of ACEi-AE is still a matter of debate. Corticosteroids and antihistamines do not show efficacy. Some therapeutic attempts have shown some efficacy for fresh frozen plasma or C1 inhibitor concentrate infusion. Interventional studies with the specific bradykinin receptor antagonist icatibant have shown conflicting results; there might be a different ethnic predisposition to icatibant efficacy which has been proven in caucasian but not in black patients.

Significant predictive factors of the severity and outcomes of the first attack of acute angioedema in children

Background

The initial episode of angioedema in children can be potential life-threatening due to the lack of prompt identification and treatment. We aimed to analyze the factors predicting the severity and outcomes of the first attack of acute angioedema in children.

Methods

This was a retrospective study with 406 children (< 18 years) who presented in the emergency department (ED) with an initial episode of acute angioedema and who had subsequent follow-up visits in the out-patient department from January 2008 to December 2014. The severity of the acute angioedema was categorized as severe (requiring hospital admission), moderate (requiring a stay in the short-term pediatric observation unit [POU]), or mild (discharged directly from the ED). The associations among the disease severity, patient demographics and clinical presentation were analyzed.

Result

In total, 109 (26.8%) children had severe angioedema, and the majority of those children were male (65.1%). Most of the children were of preschool age (56.4%), and only 6.4% were adolescents. The co-occurrence of pyrexia or urticaria, etiologies of the angioedema related to medications or infections, the presence of respiratory symptoms, and a history of allergies (asthma, allergic rhinitis) were predictors of severe angioedema (all p < 0.05). Finally, the duration of angioedema was significantly shorter in children who had received short-term POU treatment (2.1 ± 1.1 days) than in those who discharged from ED directly (2.3 ± 1.4 days) and admitted to the hospital (3.5 ± 2.0 days) (p < 0.001).

Conclusion

The co-occurrence of pyrexia or urticaria, etiologies related to medications or infections, the presence of respiratory symptoms, and a history of allergies were predictors of severe angioedema. More importantly, short-term POU observation and prompt treatment might be benefit for patients who did not require hospital admission.

Novel Therapeutic Approaches Targeting the Renin-Angiotensin System and Associated Peptides in Hypertension and Heart Failure

Despite the success of renin-angiotensin system (RAS) blockade by angiotensin-converting enzyme (ACE) inhibitors and angiotensin II type 1 receptor (AT1R) blockers, current therapies for hypertension and related cardiovascular diseases are still inadequate. Identification of additional components of the RAS and associated vasoactive pathways, as well as new structural and functional insights into established targets, have led to novel therapeutic approaches with the potential to provide improved cardiovascular protection and better blood pressure control and/or reduced adverse side effects. The simultaneous modulation of several neurohumoral mediators in key interconnected blood pressure-regulating pathways has been an attractive approach to improve treatment efficacy, and several novel approaches involve combination therapy or dual-acting agents. In addition, increased understanding of the complexity of the RAS has led to novel approaches aimed at upregulating the ACE2/angiotensin-(1-7)/Mas axis to counter-regulate the harmful effects of the ACE/angiotensin II/angiotensin III/AT1R axis. These advances have opened new avenues for the development of novel drugs targeting the RAS to better treat hypertension and heart failure. Here we focus on new therapies in preclinical and early clinical stages of development, including novel small molecule inhibitors and receptor agonists/antagonists, less conventional strategies such as gene therapy to suppress angiotensinogen at the RNA level, recombinant ACE2 protein, and novel bispecific designer peptides.

Immune pathomechanism and classification of drug hypersensitivity

Drug hypersensitivity reactions (DHR) are based on distinct mechanisms and are clinically heterogeneous. Taking into account that also off-target activities of drugs may lead to stimulations of immune or inflammatory cells, three forms of DHR were discriminated: the allergic-immune mechanism relies on the covalent binding of drugs/chemicals to proteins, which thereby form new antigens, to which a humoural and/or cellular immune response can develop. In IgE-mediated drug allergies, a possible tolerance mechanism to the drug during sensitization and the need of a covalent hapten-carrier link for initiation, but not for elicitation of IgE-mediated reactions is discussed. The p-i ("pharmacological interaction with immune receptor") concept represents an off-target activity of drugs with immune receptors (HLA or TCR), which can result in unorthodox, alloimmune-like stimulations of T cells. Some of these p-i stimulations occur only in carriers of certain HLA alleles and can result in clinically severe reactions. The third form of DHR ("pseudo-allergy") is represented by drug interactions with receptors or enzymes of inflammatory cells, which may lead to their direct activation or enhanced levels of inflammatory products. Specific IgE or T cells are not involved. This classification is based on the action of drugs and is clinically useful, as it can explain differences in sensitizations, unusual clinical symptoms, dependence on drug concentrations, predictability and immunological and pharmacological cross-reactivities in DHR.

[Drug-induced angioedema : Focus on bradykinin]

On a pathophysiological level, angioedema can be differentiated into histamine- and bradykinin-mediated types. The prototype drug-associated, bradykinin-mediated form of angioedema is angiotensin-converting enzyme (ACE) inhibitor-induced angioedema. The hypothesized cause is a decrease in bradykinin degradation via ACE inhibition. In this scenario, other bradykinin-degrading enzymes assume major importance. When the effect of these enzymes is also diminished, e. g., due to genetic variants or external factors, compensation for the inhibition of ACE may be insufficient. An increased risk of angioedema has also been reported for other drugs, particularly when prescribed in combination with ACE inhibitors. Here, the suspected cause also relates to the degradation of bradykinin. When angioedema arises within the context of concomitant ACE inhibitor use, additive bradykinin degradation effects may be implicated.

[Acquired C1 esterase inhibitor deficiency via bradykinin-mediated angioedema: Four cases]

BACKGROUND

Acquired C1-esterase inhibitor (C1-INH) deficiency angioedema (C1-INH-AAE) is a form of bradykinin-mediated angioedema. This rare disorder is due to acquired consumption of C1-INH, hyperactivation of the classic pathway of human complement, and potentially fatal recurrent angioedema symptoms. Clinical symptoms of C1-INH-AAE are very similar to those of hereditary angioedema (HAE) but usually appear after the fourth decade of life and induce abdominal pain less frequently. Laboratory tests are essential in establishing the diagnosis with low levels or abnormal structure and function of C1-INH. Most patients present C1-INH autoantibodies. Furthermore, C1q is reduced in AAE, contrary to HAE. The long-term prognosis is determined by associated hematologic malignancies.

PATIENTS AND METHODS

We report 4 cases of C1-INH-AAE associated with lymphoproliferative disorders referred to the Reference Centre for Angioedema of Besançon, France. The patients were aged between 60 and 77 years. C1 INH antibodies were found in three patients. Symptoms were triggered by angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) in 3 patients. Hematologic malignancy was present at diagnosis (one case of chronic lymphoid leukemia) or was diagnosed during follow-up (one case of indolent marginal zone non-Hodgkin lymphoma and two cases of monoclonal gammopathy).

DISCUSSION

C1-INH-AAE induced by ACE inhibitors or ARBs may be associated with hematologic malignancies. This form of revelation does not necessarily indicate a diagnosis of ACE or ARBs angioedema, and screening should therefore be performed for C1 Inh and C1q. An underlying hematologic malignancy should be routinely sought and the long-term prognosis determined.

Pharmacotherapy for Angiotensin-Converting Enzyme Inhibitor–Induced Angioedema: A Systematic Review

Objective

Angioedema is a potentially life-threatening complication of angiotensin-converting enzyme inhibitor (ACEI) use, occurring in up to 0.5% of users. Although the pathophysiology of ACEI-induced angioedema is attributable to elevated serum bradykinin, standard management typically includes corticosteroids and antihistamines. We sought to summarize the evidence supporting pharmacotherapy for ACEI-induced angioedema.

Data Sources

PubMed, MEDLINE, and Embase portals.

Methods

A systematic literature review was conducted according to the PRISMA guidelines. Databases were queried by 3 independent reviewers for English-language studies published between 1980 and 2017. The initial search screened for all occurrences of “angioedema” and then was further refined to include studies of ACEI-related cases and exclude hereditary angioedema.

Results

Five articles representing 218 cases were identified, including 3 randomized controlled trials and 2 prospective case series with historical controls. One of 2 studies of icatibant (bradykinin B2 receptor antagonist) found more rapid symptom improvement than that with a control group of corticosteroids and antihistamines. Two studies of ecallantide (plasma kallikrein inhibitor) and 1 study of C1 inhibitor replacement found no significant benefit over control. No studies were identified that compared the efficacy of corticosteroids with antihistamines, of one dose with another, of fresh frozen plasma, or of combination therapy.

Conclusion

The efficacy of treatment of ACEI-induced angioedema with bradykinin antagonists, kallikrein inhibitor, and C1 inhibitor warrants further study. Although consistent benefit of these medications has not been demonstrated, their use has not caused harm. One study examining off-label use of icatibant has demonstrated efficacy over control. In addition, further study is needed to establish the efficacy and mechanism of action of standard pharmacotherapy such as corticosteroids and antihistamines in treatment of this condition.