Emerging concepts in the diagnosis and treatment of patients with undifferentiated angioedema

Corticosteroids in critically ill patients: A narrative review

Corticosteroids have been utilized in modern medicine for decades. Many indications have been investigated across various treatment settings with both benefit and harm observed. Given the instability of critically ill patients, the increased risk of corticosteroid-related complications, and the pervasive comorbidities, patients who receive corticosteroids must be carefully managed. Common critical care disease states in which corticosteroids have been studied and are routinely utilized include acute respiratory distress syndrome, adrenal insufficiency, angioedema, asthma, chronic obstructive pulmonary disease, community-acquired pneumonia, coronavirus disease 2019, septic shock, and spinal cord injury. Benefits of corticosteroids include an improvement in disease state-specific outcomes, decreased hospital length of stay, decreased mechanical ventilatory support, and decreased mortality. The harm of corticosteroids is well documented through adverse effects that include, but are not limited to, hyperglycemia, tachycardia, hypertension, agitation, delirium, anxiety, immunosuppression, gastrointestinal bleeding, fluid retention, and muscle weakness. Furthermore, corticosteroids are associated with increased health care costs through adverse effects as well as drug acquisition and administration costs. Given the assortment of agents, dosing, benefits, risks, and utilization in the critical care setting, there may be difficulty with identifying the appropriate places for use of corticosteroids in therapy. There currently exists no comprehensive report detailing the use of corticosteroids in the aforementioned disease states within the critical care setting. This narrative review sets out to describe these in detail.

Blood Adhesion Molecules as Biomarkers in Children with Chronic Urticaria

BACKGROUND

The prevailing etiological model of both acute and chronic urticaria implicates specific allergen exposure that triggers the local release of vasoactive factors and inflammatory adhesion molecules, including vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), endothelial leukocyte adhesion molecule 1 (ELAM-1), P-selectin and E-selectin in the superficial dermis. This study focused on the possible role of VCAM-1 and ICAM-1 as biomarkers in children with acute and chronic urticaria.

METHODS

This study involved 184 children, 40 with acute urticaria, 71 with chronic urticaria, and 73 matched comparison subjects. The serum levels of ICAM-1 and VCAM-1 were determined in venous blood in all the participants on enrollment. Antihistamine treatment was administered to all the patients. In the children with chronic urticaria, the Urticaria Activity Score Questionnaire (UAS7) was completed daily by the parents. In 16 of the patients with acute urticaria and 43 with chronic urticaria, the serum levels of ICAM-1 and VCAM-1 were determined at follow-up after 6-8 weeks of treatment.

RESULTS

The mean serum levels of both VCAM-1 and ICAM-1 were higher in both groups of children with urticaria than in the comparison subjects at the start of the study. In the chronic urticaria group, the levels decreased significantly (p = 0.03 and p = 0.01, respectively) following treatment. Similarly, the acute urticaria group exhibited significant reduction in the mean levels of VCAM and ICAM (p < 0.001). In both groups, the mean level of ICAM after treatment was comparable with that of the comparison group.

CONCLUSIONS

VCAM-1 and ICAM-1 are suggested as promising biomarkers for monitoring both acute and chronic urticaria in children. Future research should explore their utility in larger cohorts and investigate their role in personalized treatment strategies.

Bradykinin Metabolism and Drug-Induced Angioedema

Bradykinin (BK) metabolism and its receptors play a central role in drug-induced angioedema (AE) without urticaria through increased vascular permeability. Many cardiovascular and diabetic drugs may cause BK-mediated AE. Angiotensin-converting enzyme inhibitors (ACEIs) and neprilysin inhibitors impair BK catabolism. Dipeptidyl peptidase-IV (DPP-IV) inhibitors reduce the breakdown of BK and substance P (SP). Moreover, angiotensin receptor blockers, thrombolytic agents, and statins may also induce BK-mediated AE. Understanding pathophysiological mechanisms is crucial for preventing and treating drug-induced AE.

The multifactorial impact of receiving a hereditary angioedema diagnosis

Hereditary angioedema (HAE) is a rare, chronic, debilitating genetic disorder characterized by recurrent, unpredictable, and potentially life-threatening episodes of swelling that typically affect the extremities, face, abdomen, genitals, and larynx. The most frequent cause of HAE is a mutation in the serpin family G member 1 (SERPING1) gene, which either leads to deficient plasma levels of the C1-esterase inhibitor (C1-INH) protein (type I HAE-C1-INH) or normal plasma levels of dysfunctional C1-INH protein (type II HAE-C1-INH). Mutations in SERPING1 are known to be associated with dysregulation of the kallikrein-bradykinin cascade leading to enhancement of bradykinin production and increased vascular permeability. However, some patients present with a third type of HAE (HAE-nl-C1-INH) that is characterized by normal plasma levels and functionality of the C1-INH protein. While mutations in the factor XII, angiopoietin-1, plasminogen, kininogen-1, myoferlin, and heparan sulfate-glucosamine 3-O-sulfotransferase-6 genes have been identified in some patients with HAE-nI-C1-INH, genetic cause remains unknown in many cases with further research required to fully elucidate the pathology of disease in these patients. Here we review the challenges that arise on the pathway to a confirmed diagnosis of HAE and explore the multifactorial impact of receiving a HAE diagnosis. We conclude that it is important to continue to raise awareness of HAE because delays to diagnosis have a direct impact upon patient suffering and quality of life. Since many patients will seek help from hospitals during their first swelling attack it is vital that emergency department staff are aware of the different pathological pathways that distinguish HAE from other forms of angioedema to ensure that the most appropriate treatment is administered. As disease awareness increases, it is hoped that patients will be diagnosed earlier and that pre-authorization and insurance coverage of HAE treatments will become easier to obtain, ultimately reducing the burden of treatment for these patients and their caregivers.

Profiling the disintegration of BRPs released by massive wasp stings using serratiopeptidase: An in-silico insight

Serratiopeptidase is a multifaceted therapeutic enzyme renowned for its anti-inflammatory, analgesic, anti-biofilm, fibrinolytic, and anti-edemic properties. It is vital to uncover more about the assets of such efficacious enzyme in order to facilitate their contribution in all health-related issues, notably inflammatory ailments. The current study sought to determine whether serratiopeptidase would disintegrate bradykinin related peptides (BRPs) from wasp venom in the same manner as it does with human bradykinin. To accomplish this objective, we docked selected BRPs onto the binding pocket of wild and previously identified mutant (N412D) of serratiopeptidase. Based on their docked scores, the top two BRPs were selected, and their conformational behavior was analyzed employing molecular dynamics studies. Additionally, thermodynamics end-state energy analysis reported that both the complexes exhibited higher stability and identical ΔG values when compared to the reference complex. Further, we condemned the external pulling forces on both peptides to observe the force needed in the disassociation process to endorse the binding affinity findings in terms of unbinding mechanism. This analysis suggested that BRP-7 (Wasp kinin PMM1) peptide was tightly anchored and laid out the highest pulling force to get detach from the active pocket of serratiopeptidase in contrast to the BRP-6 peptide. The current study endorses up the present findings and paves the way for serratiopeptidase to be used as an anti-angioedemic peptidase as well as a fixed-dose combination (FDC) in hypotensive drugs.

A Comprehensive Review of Bradykinin-Induced Angioedema Versus Histamine-Induced Angioedema in the Emergency Department

Angioedema (AE) is a condition that is frequently encountered in the emergency department (ED). It is a rare condition with localized, asymmetrical swelling of the skin and/or mucosa that is frequently nonpruritic and primarily affects locations with loose connective tissue. Physicians must have a thorough understanding of this condition since it can cause fatal airway compromise, which might be the presenting symptom. Histamine-mediated AE is the most common type of AE seen in EDs. However, ED physicians must be on the lookout for the less common bradykinin-mediated types of AE as these do not respond to the same therapy as histamine-mediated AE. Hospitals may lack specialized drugs or protocols, and many ED staff may be unable to identify or treat bradykinin-mediated AE. It is crucial to understand the pathophysiology of the various kinds of AE in order to optimize treatment. The goal of this review paper is to provide an overview of the pathophysiology, clinical manifestations, and treatment options for bradykinin and histamine-induced AE in the ED.

A Case of Recurrent Isolated Uvula Oedema Secondary to Obesity and Obstructive Sleep Apnoea

A 34-year-old male presented as an emergency with sudden onset globus, stertor and choking whilst asleep. He had similar previous episodes that self-resolved. The patient's observations were all within normal range. On examination, he had a grossly enlarged, non-erythematous uvula and there were no signs of respiratory distress or stridor. He was managed with intravenous dexamethasone and an attempt at needle aspiration of the uvula was made but there was no clinical improvement in the patient's condition. Despite no improvement with therapy, he was monitored overnight for any signs of airway compromise and discharged the following morning. His symptoms completely resolved on follow-up in the otolaryngology clinic a week later. He was diagnosed with Quincke’s oedema caused by his obesity and background of obstructive sleep apnoea. We discuss the various aetiologies, assessment, and management of Quincke’s oedema.

Clinical Manifestations and Genetic Influences in Sulfonamide-Induced Hypersensitivity

Drug hypersensitivity is an inflammatory or immune reaction induced by drugs. It can be fatal if not appropriately treated and cause the risk of long-term complications. Sulfonamides are classified as antimicrobial drugs with a broad spectrum effective for gram-positive and gram-negative bacteria. This antibacterial agent works by competitively inhibiting folic acid synthesis, which prevents the growth and proliferation of microorganisms. In its use as antibiotics, sulfonamides can also cause adverse reactions in specific individuals. It has been widely reported that sulfonamide antimicrobials cause hypersensitivity reactions mediated by IgE or T cells. This review identifies symptoms or signs that can appear, as well as genes associated with sulfonamide hypersensitivity reactions, as sulfonamide may cause hypersensitivity in the form of uveitis, skin rash, Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN), parotitis, angioedema, drug reaction with eosinophilia and systemic symptoms (DRESS), and pruritus. In addition, several genes were found to be associated with sulfonamide hypersensitivity, including HLA-A29, HLA-B12, HLA-DR7, HLA-B44, and HLA A*11:01.

CAN'T INTUBATE, CAN'T OXYGENATE: A RARE CASE OF A DIFFICULT AIRWAY DUE TO NONHEREDITARY ANGIOEDEMA

Angioedema is a form of allergic mediated by histamine and non-allergic mediated by bradykinin and can be lethal if not recognized and treated promptly. This case demonstrates the proper diagnosis of and intervention in rapid onset severe angioedema. A 68-year-old male came to the emergency department with a complaint of dyspnea that started two hours before. He had type II diabetes, chronic kidney disease and several different antihypertensive medications, including an ACE inhibitor for hypertension. During physical examination, the patient was hypertensive, tachycardic, tachypnoic, and edematous. During his stay in the ED he was treated with a combination of corticosteroids, antihistamines and epinephrine, but the patient’s edema and dyspnea worsened and his oxygen saturation started to deteriorate with a progression of skin edema. Intubation was not possible due to the large edema of the tongue, so a tracheotomy was done. An ampule of icatibant was administered and rapid regression of the edema, along with the stabilization of the patient’s vital signs, followed after five minutes. The patient was discharged home after five days with a recommendation of discontinuing the ACE inhibitor. While non-hereditary angioedema is not a rare condition, emergency physicians should be adequately educated about it.

Assessment of Clinical Diagnostic Efficacy of Pulmonary Function Test Based on DBN-SVM of Pediatric Asthma and Cough Variant Asthma

The diagnosis of asthma depends on the unprejudiced proof of the varying airflow obstruction. The pulmonary function tests are carried out to evaluate the clinical value of different types of respiratory diseases in children or infants. This study is focused on the clinical evaluation of the pulmonary function tests in the diagnosis of pediatric asthma and cough variant asthma. A differential diagnosis method for chronic obstructive pulmonary disease (COPD) and asthma-COPD overlap with complementary diagnostic value is proposed. For the pulmonary function tests, the COPD gene dataset was selected and feature selection was performed using the DBN-SVM scoring method. For analysis and comparison, the differential diagnosis models were built using ROC curves for the accuracy of the deep belief network model and the support vector machine model. The sensitive features associated with COPD and ACO classification using the deep belief network model were found to be in good agreement with known clinical diagnostic strategies. The clinical diagnosis tests for pulmonary pediatric asthma and cough variant asthma were conducted on two groups of children, with both groups containing a basis of comparison. 80 cases of pediatric asthma and cough variant asthma were admitted from 2013 to 2014 and 80 cases of children with a healthy physical examination. The results of the two groups were compared. The results showed that the levels of FEV1, PEF, and FVC were significantly lower (P < 0.05), in healthy children, and FEV1/FVC%, RV, and RV/TCL% were significantly higher (P < 0.05) in children with asthma and cough variant asthma during acute exacerbation and chronic persistence. There were no statistically significant differences in the duration of clinical remission (P > 0.05). Thus, the study suggests that confirmed cases of the diagnosis of pediatric asthma and cough variant asthma by pulmonary function tests were significantly higher than those of conventional tests (P < 0.05). From this study, we can conclude that pulmonary function tests can accurately diagnose pediatric asthma and cough variant asthma, and also accurately reflect the development of the child's disease, which is of high clinical value.

Bradykinin-induced angioedema in the emergency department

Background

Acute airway angioedema commonly occurs through two distinct mechanisms: histamine- and bradykinin-dependent. Although they respond to distinct treatments, these two potentially life-threatening states present similarly. Poor recognition of the bradykinin-dependent pathway leads to treatment errors in the emergency department (ED), despite the availability of multiple pharmacologic options for hereditary angioedema (HAE) and other forms of bradykinin-induced angioedema. Here, we consider the pathophysiology and clinical features of bradykinin-induced angioedema, and we present a systematic literature review exploring the effectiveness of the available therapies for managing such cases.

Methods

PubMed searches using ‘emergency’, ‘bradykinin’ and various therapeutic product names identified studies reporting the efficacy of treatments for bradykinin-induced angioedema in the ED setting. In all, 22 studies met prespecified criteria and are analysed here.

Findings

Whereas histamine-induced angioedema has a faster onset and often presents with urticaria, bradykinin-induced angioedema is slower in onset, with greater incidence of abdominal symptoms. Acute airway angioedema in the ED should initially be treated with anaphylactic protocols, focusing on airway management and treatment with epinephrine, antihistamine and systemic steroids. Bradykinin-induced angioedema should be considered if this standard treatment is not effective, despite proper dosing and regard of beta-adrenergic blockade. Therapeutics currently approved for HAE appear as promising options for this and other forms of bradykinin-induced angioedema encountered in the ED.

Conclusion

Diagnostic algorithms of bradykinin-induced angioedema should be followed in the ED, with early use of approved therapies to improve patient outcomes.

Resolution of Laryngeal Oedema in a Patient with Acquired C1-Inhibitor Deficiency. a Case Report

Introduction

Laryngeal oedema caused by acquired angioedema due to C1-inhibitor deficiency (C1-INH-AAE) is a life-threatening condition. The swelling is bradykinin mediated and will not respond to the usual treatment with antihistamines, corticosteroids, or epinephrine. Instead, kallikrein-bradykinin-targeted therapies should be used promptly to prevent asphyxiation.

Case presentation

A 43 years old female presented at the Hereditary Angioedema Centre reporting a one-year history of peripheral, facial, and neck oedema. Treatment with antihistamines and corticosteroids had been ineffective. Laboratory results showed complement level deficiencies and monoclonal gammopathy characterised as immunoglobulin M. An abdominal ultrasound revealed splenomegaly. A bone marrow biopsy was normal. Based on these data, the diagnosis of C1-INH-AAE associated with monoclonal gammopathy of uncertain significance (MGUS) was made. As C1-INH-AAE can present with life-threatening, standard treatment-resistant laryngeal oedema, an emergency care treatment plan was proposed, and the patient was advised to present to the emergency department (ED) with this medical letter. Based on these recommendations, three laryngeal attacks were successfully treated in the ED with recombinant human C1-inhibitor (two attacks) and fresh frozen plasma (one attack). After these episodes, the patient was prescribed prophylactic treatment with antifibrinolytics. No further angioedema attacks were reported by the patient at the 18 months follow-up visit.

Conclusions

Because angioedema of the upper airways is a life-threatening condition, recognising the specific type of swelling by the emergency physician is critical in providing immediate and effective treatment to reduce the associated risk of asphyxiation. C1-INH-AAE being a rare disorder, patients should have available an emergency care treatment plan with recommendations of acute treatment possibilities.

Angioedema: differential diagnosis and acute management

A clinical vignette illustrates a typical presentation of a patient seeking help for acute angioedema. Despite the risks of SARS-CoV-2 (COVID-19) exposure, it is critical to evaluate patients with acute angioedema in person, because there is always the potential for angioedema to progress to the head, neck, or lungs, which can rapidly compromise the airways and require immediate intervention to avoid potential asphyxiation. There are three mediators of angioedema, histamine, leukotriene, or bradykinin, each requiring different management. This article provides clinicians essential information for differentiating between these types of angioedema, including an overview of the underlying pathogenies of angioedema, and the subjective and objective findings that are useful in differentiating between angioedema types. The article ends with the appropriate management for each type of acute angioedema, including the medications approved by the FDA for on-demand treatment of an HAE attack.

Assessment of disease activity and quality of life in patients with recurrent bradykinin-mediated versus mast cell-mediated angioedema

Objective

Recurrent Angioedema (RAE) is characterized by sudden swelling of mucosal surfaces or deep dermis and is either mast cell-(MMAE) or bradykinin-mediated (BMAE). How patients with BMAE and MMAE differ in terms of disease activity and impact remains largely unknown. Here, we determined validity, reliability, and sensitivity to change of Turkish versions of angioedema activity score (AAS) and quality of life questionnaire (AE-QoL) and used both instruments to investigate and compare patients with BMAE and MMAE.

Methods

Turkish versions of AAS28 and AE-QoL were applied to 94 patients with RAE (18–72 years). Patients’ global self-assessment of QoL (PGA-QoL), disease activity (PGA-DA-VRS, PatGA-DA-VAS), and 12-Item-Short Form Survey were used at week 4 (visit 2), and week 8 (visit 3). Demographic characteristics, clinical features, and AAS28 and AE-QoL values were compared between 31 patients with BMAE and 63 patients with MMAE.

Results

Turkish AAS28 and AE-QoL showed excellent internal consistency, high reproducibility and known-groups validity. Compared to patients with MMAE, BMAE patients were younger (34.6 ± 10.7 vs. 40.7 ± 13.3 years), had longer disease duration (236 ± 178 vs. 51 ± 78 months), high prevalence of family history (63% vs 14%), longer duration of attacks (65 ± 20 vs. 40 ± 25 h), and they were more commonly affected by upper airway angioedema (70% vs 23%). Disease activity (AAS28) was lower (29.3 ± 24.6 vs 55.2 ± 52.9), but AE-QoL was higher (44.2 ± 16.1 vs 34.5 ± 22.5) in BMAE patients as compared to MMAE patients.

Conclusions

Patients with BMAE and MMAE have distinct disease characteristics. Recurrent bradykinin-mediated angioedema impacts quality of life more than mast cell-mediated angioedema. The discriminating characteristics of patients with BMAE and MMAE may help to improve the diagnosis and management of patients with RAE.

Roles of Immune Cells in Hereditary Angioedema

Hereditary angioedema (HAE) is a rare genetic disease, characterized by recurrent and unexpected potentially life-threatening mucosal swelling. HAE may be further classified into HAE with C1‐inhibitor deficiency (C1‐INH‐HAE) and HAE with normal C1‐INH activity (nlC1‐INH‐HAE), mostly due to mutations leading to increased vascular permeability. Recent evidence implicates also the innate and adaptive immune responses in several aspects of angioedema pathophysiology. Monocytes/macrophages, granulocytes, lymphocytes, and mast cells contribute directly or indirectly to the pathophysiology of angioedema. Immune cells are a source of vasoactive mediators, including bradykinin, histamine, complement components, or vasoactive mediators, whose concentrations or activities are altered in both attacks and remissions of HAE. In turn, through the expression of various receptors, these cells are also activated by a plethora of molecules. Thereby, activated immune cells are the source of molecules in the context of HAE, and on the other hand, increased levels of certain mediators can, in turn, activate immune cells through the engagement of specific surface receptors and contribute to vascular endothelial processes that lead to hyperpemeability and tissue edema. In this review, we summarize recent developments in the putative involvement of the innate and adaptive immune system of angioedema.

Recognition, Evaluation, and Management of Pediatric Hereditary Angioedema

ABSTRACT

Hereditary angioedema (HAE) is a rare, often underrecognized genetic disorder caused by either a C1 esterase inhibitor deficiency (type 1) or mutation (type 2). This leads to overproduction of bradykinin resulting in vasodilation, vascular leakage, and transient nonpitting angioedema occurring most frequently in the face, neck, upper airway, abdomen, and/or extremities. Involvement of the tongue and laryngopharynx has been associated with asphyxiation and death. Hereditary angioedema is an autosomal-dominant condition; therefore, there is a 50% chance an offspring will inherit this disorder. Any patient presenting with isolated angioedema should be screened with a C4 measurement, as 25% of cases have no family history of HAE. All patients with HAE will have a functional deficiency of C1 esterase inhibitor. Contributors that delay the diagnosis of HAE include recognition delay by clinicians who confuse this condition with histaminergic angioedema, the disease's varied presentations, and limitations to timely testing. Pediatric emergency clinicians should be knowledgeable about how to distinguish between bradykinin- and histamine-mediated angioedema, as there are significant differences in the diagnostic testing, treatment, and clinical response between these 2 different conditions. Evidence indicates that early diagnosis and treatment of HAE reduces morbidity and mortality. Clinician recognition of the mechanistically different problems will ensure patients are appropriately referred to an expert for outpatient management.

Case Report: Compromised Airway Following Anesthesia and Its Correlation With the Use of ACE Inhibitors-An Unexpected Clinical Event and Review of Literature

Angiotensin-converting enzyme inhibitors associated angioedema involving the upper aerodigestive tract is indisputably a hazardous airway condition which is clinically poorly recognized and frequently underestimated. We describe and present case of a 70-year old man on ramipril who developed massive tongue swelling post-operatively after unremarkable laryngeal mask anaesthesia which was fortuitously managed conservatively. High index of suspicion, timely recognition and knowledge of pathophysiology and the clinical course should guide airway and further supportive management in these patients.

Extending our understanding of exenatide: a rare case of angio-oedema

Exenatide is a subcutaneous injectable glucagon-like peptide 1 receptor agonist that has been approved by the Federal Drug Administration for the treatment of type 2 diabetes mellitus. While side effects such as nausea, vomiting and local hypersensitivity reactions are more commonly described, angio-oedema has never been previously reported in the literature. We present the case of a 67-year-old woman who presented to the emergency department with acute-onset tongue swelling, difficulty breathing, dizziness and diffuse itching which began shortly after receiving her first dose of intramuscular extended release (ER) exenatide. This case aims to raise awareness of the potential adverse effect of angio-oedema secondary to exenatide ER and serves as a reminder to clinicians to discuss possible adverse effects of medications and early recognition of symptoms which would prompt further medical attention.

Evaluation of staging criteria for disposition and airway intervention in emergency department angioedema patients

AIM

Angioedema is a nonpitting edema that can lead to death secondary to airway obstruction. Previously, a staging system based on localization of the angioedema was proposed for risk stratification of likelihood of need for admission or airway intervention. This study aims to evaluate a staging system based on angioedema localization as a method of predicting need for admission or airway intervention.

METHODS

This was a retrospective chart review of angioedema cases that presented to an academic emergency department (ED) from August 1, 2006, to January 31, 2018. Data were collected on location of swelling, treatment setting, and medical and procedural interventions. Cases were categorized by modified Ishoo criteria, defined as follows: 1, lips, face, periorbital, extremities, total body/diffuse swelling; 2, soft palate, posterior pharynx; 3, tongue; 4, larynx. Predictive probability of disposition by stage was then compared.

RESULTS

A total of 320 patients were included in this study (median age, 44 years; 54.4% female). Stage 4 was more likely to require intensive care unit care without (probability 17%) and with (67%) airway intervention compared with stage 1 without (2.5%) and with (0.1%) airway intervention. Conversely, stage 1 was more likely to be treated in ED and discharged (85%) compared with stage 4 (0%). Stage 4 was also more likely to require airway intervention (67%) compared with other stages (1, 0.1%; 2, 8.6%; 3, 16%).

CONCLUSION

Higher-stage patients were more likely to require higher levels of care and airway intervention. Thus, the staging system appears to be a valid method of predicting risk among ED angioedema patients.

Tranexamic acid for ACE inhibitor induced angioedema - A case report

Tranexamic acid (TXA) is an antifibrinolytic agent which inhibits conversion of plasminogen to plasmin, a key step in kallikrein activation and bradykinin formation. Tranexamic acid is used in prophylactic management of hereditary angioedema; however, evidence for TXA in angiotensin converting enzyme (ACE) inhibitor-induced angioedema (ACEI-AE) is limited. We describe a patient who presented to the emergency department with ACEI-AE who was successfully treated with TXA. This case suggests that TXA may be a beneficial treatment modality in the management of ACEI-AE and warrants further investigation.

Angiotensin-converting enzyme 2, the complement system, the kallikrein-kinin system, type-2 diabetes, interleukin-6, and their interactions regarding the complex COVID-19 pathophysiological crossroads

Because of the current COVID-19-pandemic, the world is currently being held hostage in various lockdowns. ACE2 facilitates SARS-CoV-2 cell-entry, and is at the very center of several pathophysiological pathways regarding the RAAS, CS, KKS, T2DM, and IL-6. Their interactions with severe COVID-19 complications (e.g. ARDS and thrombosis), and potential therapeutic targets for pharmacological intervention, will be reviewed.

Ezetimibe: An Unusual Suspect in Angioedema

We describe a case of new onset angioedema likely due to Ezetimibe therapy in an elderly patient with a prior history of drug-induced bradykinin reactions who had been on the medication for multiple years. This is the second reported incidence of Ezetimibe-associated angioedema in literature. A 90-year-old African American female presented with angioedema of the face and oral mucosa with associated difficulty speaking developing hours after taking Ezetimibe 10 mg PO. She denied adding any new or unusual foods to her diet. A thorough clinical history determined Ezetimibe was the likely culprit. Ezetimibe was immediately discontinued. The swelling subsided after administration of methylprednisolone 125 mg, epinephrine 1 mg/mL, injection 0.3 mL, diphenhydramine 25 mg, and famotidine 20 mg BID within 48 hours. The patient's C1 esterase inhibitor level was measured to be within normal limits. Food panel allergy testing showed very low or undetectable IgE levels in all categories. Based on the limited reports in literature and our current case, we conclude that there is a likely association of angioedema with Ezetimibe. The mechanism, however, is unknown since it is not related to bradykinin or mast cell-mediated activation. Clinicians should advise patients taking Ezetimibe to report any swelling of the lips, face, and tongue and to immediately discontinue its use if these signs are present.

A novel functional C1 inhibitor activity assay in dried blood spot for diagnosis of Hereditary angioedema

BACKGROUND

Hereditary angioedema (HAE) is a rare genetic disease caused by deficiency or dysfunction of C1 esterase inhibitor (C1-INH). Timely and accurate diagnosis is an ongoing challenge. Measurement of plasma C1-INH activity is currently the critical standard test. We describe a novel and highly robust point-of-care assay to quantify C1-INH activity in dried blood spot (DBS).

METHODS

C1-INH was extracted from 3 mm punches of DBS samples and incubated with excess amount of C1 esterase (C1s). The mixture was subsequentially incubated with C1s substrate, followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) quantitation of the enzyme reaction product.

RESULTS

The assay was validated within a quantification range from 100 to 1500 mU/mL. The intra-day precision and accuracy ranged from 4.0% to 11.6% and -11.1% to -2.1%, and the inter-day precision and accuracy were 8.1-13.1% and -10.3% to 0.9%, respectively. Normal C1-INH activity (n = 103) ranged from 311 to 1090 mU/mL, whereas 23 out of 24 HAE patients exhibited C1-INH activity lower than 100 mU/mL.

CONCLUSION

DBS specimen collection for measurement of functional C1-INH activity in a physician's office is straightforward and not limited by logistic considerations and therefore, appropriate for the diagnosis of HAE in high throughput diagnostic laboratories.

Angioedema associated with thrombolysis for ischemic stroke: analysis of a case-control study

BACKGROUND

Bradykinin-mediated angioedema (AE) is a complication associated with thrombolysis for acute ischemic stroke. Risk factors are unknown and management is discussed.

OBJECTIVES

To clarify risk factors associated with bradykinin-mediated AE after thrombolysis for acute ischemic stroke.

METHODS

In a case-control study conducted at a French reference centre for bradykinin angiœdema, patients with thrombolysis for acute ischemic stroke and a diagnosis of bradykinin-mediated angiœdema, were compared to controls treated with thrombolysis treatment without angiœdema.

RESULTS

Fifty-three thrombolysis-related AE were matched to 106 control subjects. The sites of attacks following thrombolysis for ischemic stroke mainly included tongue (34/53, 64%) and lips (26/53, 49%). The upper airways were involved in 37 (70%) cases. Three patients required mechanical ventilation. Patients with bradykinin-mediated angiœdema were more frequently women [33 (62%) vs. 44 (42%); P = 0.01], had higher frequency of prior ischemic stroke [12 (23%) vs. 9 (8%); P = 0.01], hypertension [46 (87%) vs. 70 (66%); P = 0.005], were more frequently treated with angiotensin-converting enzyme inhibitor [37 (70%) vs. 28 (26%); P < 0.001] and were more frequently hospitalized in intensive care medicine [ICU; 11 (21%) vs. 5 (5%); P = 0.004]. In multivariate analysis, factors associated with thrombolysis-related AE were female sex [odds ratio (OR), 3.04; 95% confident interval (CI), 1.32-7.01; P = 0.009] and treatment with angiotensin-converting enzyme inhibitors [(OR), 6.08; 95% (CI), 2.17-17.07; P < 0.001].

CONCLUSIONS

This case-control study points out angiotensin-converting enzyme inhibitors and female sex as risk factors of bradykinin AE associated with thrombolysis for ischemic stroke.

Acquired Angioedema: A Rare Manifestation of Angioimmunoblastic T Cell Lymphoma

The clinical presentation except age of onset is similar in different types of angioedema. A lymphoproliferative disorder like angioimmunoblastic T cell lymphoma (AITL) rarely presents with symptoms of angioedema. We present extremely rare case of elderly male with recurrent tongue swelling, pruritus with normal levels of complements and C1 esterase inhibitor protein featuring as acquired angioedema, a rare manifestation of AITL. Initial response to corticosteroids may be misleading and occurs as a result of immunosuppression of AITL. High index of suspicion may prompt need for histopathological diagnosis of lymph node biopsy. Definitive chemotherapeutic treatment may achieve long term remission.

A Case of Oropharyngeal Angioedema Following Intravenous Recombinant Tissue Plasminogen Activator (rt-PA) and Mechanical Thrombectomy

A 72-year-old housewife presented with ischemic cerebrovascular stroke. Intravenous thrombolysis using recombinant tissue plasminogen activator (rt-PA) followed by mechanical thrombectomy under general anesthesia were attempted. The patient developed stridor and tongue swelling, in addition to hypotension and bradycardia, 60 min after completion of the rt-PA infusion. The airway was intubated, and intramuscular adrenaline, together with intravenous hydrocortisone and diphenhydramine, were administered. On the second day, the tongue edema subsided, and the cuff leak test was negative. However, extubation was not attempted due to the development of brain edema. A tracheostomy was later performed, and the patient was weaned off mechanical ventilation.

Caution in diagnosing angioedema as anaphylaxis

Angioedema is one of the commonest life-threatening conditions with good outcome timely definitive treatment. However, failure to recognise the common presentation of an uncommon bradykinin-mediated angioedema in time may lead to fatal outcome in the emergency department (ED). We report a case of a 79-year-old male patient who presented to ED with features of ACE inhibitor-induced angioedema which was identified and resuscitated by the emergency physician with use of fresh frozen plasma (FFP) leading to prompt recovery and good outcome.

Evaluation and Management of Angioedema in the Emergency Department

Angioedema is defined by non-dependent, non-pitting edema that affects several different sites and is potentially life-threatening due to laryngeal edema. This narrative review provides emergency physicians with a focused overview of the evaluation and management of angioedema. Two primary forms include histamine-mediated and bradykinin-mediated angioedema. Histamine-mediated forms present similarly to anaphylaxis, while bradykinin-mediated angioedema presents with greater face and oropharyngeal involvement and higher risk of progression. Initial evaluation and management should focus on evaluation of the airway, followed by obtaining relevant historical features, including family history, medications, and prior episodes. Histamine-mediated angioedema should be treated with epinephrine intramuscularly, antihistaminergic medications, and steroids. These medications are not effective for bradykinin-mediated forms. Other medications include C1-INH protein replacement, kallikrein inhibitor, and bradykinin receptor antagonists. Evidence is controversial concerning the efficacy of these medications in an acute episode, and airway management is the most important intervention when indicated. Airway intervention may require fiberoptic or video laryngoscopy, with preparation for cricothyrotomy. Disposition is dependent on patient's airway and respiratory status, as well as the sites involved.

A Forgotten Cause of Allergy at ER That Is Still Difficult to Diagnose and Treat at Poor Resource Setting: Angioedema after Using Angiotensin Converting Enzyme Inhibitors for 4 Years

Angiotensin converting enzyme inhibitors (ACEi) are the most commonly used antihypertensives. Therefore, ACEI induced angioedema (ACEi-AE) is not uncommon. Physicians tend to miss the diagnosis whenever a patient is taking the drug for years due to misbelief of “a drug that was taken for years may not be the cause for an allergic reaction or an angioedema”. But ACEi can induce angioedema after many years of usage as well as sometimes after stopping the drug even. Most of the emergency physicians and centers are not aware of clinical diagnosis and diagnostic criteria including available diagnostic tests and more importantly the treatment options of ACEi-AE. Therefore not only the diagnosis is delayed or missing but also proper treatment options are not practiced at many emergency rooms and at wards.

Consequences of Misdiagnosed and Mismanaged Hereditary Angioedema Laryngeal Attacks: An Overview of Cases from the Romanian Registry

Emergency department (ED) physicians frequently encounter patients presenting with angioedema. Most of these involve histamine-mediated angioedema; however, less common forms of angioedema (bradykinin-mediated) also occur. It is vital physicians correctly recognize and treat this; particularly since bradykinin-mediated angioedema does not respond to antihistamines, corticosteroids or epinephrine and hereditary angioedema (HAE) laryngeal attacks can be fatal. Here we present four case reports illustrating how failures in recognizing, managing, and treating laryngeal edema due to HAE led to asphyxiation and death of the patient. Recognition of the specific type of angioedema is critical for rapid and effective treatment of HAE attacks. Bradykinin-mediated angioedema should be efficiently differentiated from the most common histamine-mediated form. Improved awareness of HAE and the associated risk of life-threatening laryngeal edema among emergency physicians, patients, and relatives and clear ED treatment protocols are warranted. Moreover, appropriate treatments should be readily available to reduce fatalities associated with laryngeal edema.

Sirolimus-induced severe small bowel angioedema: A case report

RATIONALE

Drug-induced angioedema has been reported as an adverse effect of many different drugs. But small bowel angioedema associated with sirolimus (SRL) used was barely understood. It must be necessary to report a case suffering from small bowel angioedema with detailed discussion and literature review.

PATIENT CONCERNS

A 38-year-old Chinese woman presented with generalized gastric pain in the following day after renal transplantation. The patient began to crampy abdominal pain accompanied by nausea, vomiting, and diarrhea on postoperative day 6 (POD).

DIAGNOSES

We strongly suspected the angioedema was an adverse reaction to SRL.

INTERVENTION

The immunosuppressive regimen was switched from tacrolimus (TAC), SRL, and prednisone to TAC, mycophenolate and prednisone.

OUTCOMES

The symptoms were relieved within next 48 hours after withdrawing the SRL. One more CT scan showed complete resolution of bowel wall thickening and ascites.

LESSONS

This was the first report of small bowel angioedema associated with SRL. Drug-induced-angioedema is a relatively common presentation and is potentially fatal. It must be aware of potential adverse effects.

Fatal outcome of late-onset angiotensin-converting enzyme inhibitor induced angioedema: A case report

RATIONALE

Angiotensin-converting enzyme (ACE) inhibitors are one of the most used medication among patients with arterial hypertension. In most cases, ACE inhibitors caused side effects are mild; however, from 0.1% to 0.7% of patients can develop life threatening adverse effect, angioedema. Unlike histamine mediated, ACE inhibitor-related angioedema can develop at any time during the treatment course.

PATIENT CONCERNS

An 89-year-old woman with a medical history for arterial hypertension, ischemic heart disease, heart failure, chronic atrial fibrillation developed ACE inhibitor-induced angioedema after 5 years of daily ramipril administration.

DIAGNOSES

Arterial hypertension, ischemic heart disease, heart failure, chronic atrial fibrillation and late onset ACE inhibitor-induced angioedema.

INTERVENTIONS

The ACE inhibitor was used for arterial hypertension on a daily basis for the past 5 years. Patient developed airway obstruction requiring intubation. Standard therapy with epinephrine, methylprednisolone and clemastine was administered. Treatment was ineffective, considering that angioedema persisted.

OUTCOMES

Angioedema resolved after 13 days from the discontinuation of ramipril. Death due to cardiopulmonary insufficiency occurred 24 days after the admission to intensive care unit, despite full clinical resolution of ACE inhibitor-induced angioedema.

LESSONS

Our case highlight the importance of educating clinicians about ACE inhibitor-induced angioedema, as potentially fatal adverse drug reaction. Considering the fact, that no laboratory or confirmatory test exist to diagnose ACE inhibitor-induced angioedema, clinicians' knowledge is the key element in recognition of ACE inhibitor-related angioedema.

Diagnosis and treatment of upper airway oedema caused by acute angio-oedema in the emergency department: a French consensus statement

Angio-oedema is a transitory, localized, noninflammatory oedema of subcutaneous tissue or mucous. When the oedema affects the mouth, lips, tongue or larynx, it can result in fatal asphyxiation in the absence of specific treatment. Oedema secondary to plasma extravasation is usually mediated by either histamine or bradykinin. As laboratory tests are not available in an emergency setting, the implicated mediator cannot be readily determined. The challenge for the emergency physician is to determine the aetiological type, evaluate severity and initiate adapted treatment by means of a structured approach. A team of experts from the French Reference Centre for Angio-oedema reached a consensus for recommendations for the diagnostic and therapeutic strategy to be adopted by emergency departments faced with angio-oedema of the upper airways in adults. The experts defined 11 important questions. Responses were rated using a two-round Delphi methodology. The 11 recommendations were related to triage on admission, a step-by-step diagnostic protocol, definition of attack severity, discouragement of instrumental examination, prioritization of treatment for severe attacks according to clinical signs and anticipation of access to specific treatments by the hospital. Angio-oedema of the upper airways can be fatal and requires anticipation by the emergency department. A search for the aetiology, an evaluation of clinical symptoms and the availability of the treatments are challenges justifying these recommendations.

Omalizumab rapidly improves angioedema-related quality of life in adult patients with chronic spontaneous urticaria: X-ACT study data

Background

The X‐ACT study aimed to examine the effect of omalizumab treatment on quality of life (QoL) in chronic spontaneous urticaria (CSU) patients with angioedema refractory to high doses of H₁‐antihistamines.

Methods

In X‐ACT, a phase III, double‐blind, placebo‐controlled study, CSU patients (18‐75 years) with ≥4 angioedema episodes during the 6 months before inclusion were randomized (1:1) to receive omalizumab 300 mg or placebo every 4 weeks for 28 weeks. Angioedema‐related QoL, skin‐related QoL impairment, and psychological well‐being were assessed.

Results

Ninety‐one patients were randomized and 68 (omalizumab, n = 35; placebo, n = 33) completed the 28‐week treatment period. At baseline, the mean (SD) total Angioedema QoL (AE‐QoL; 56.2 [18.7] and 59.9 [19.2]) and Dermatology Life Quality Index (DLQI; 14.6 [5.7] and 16.6 [7.3]) score were high in the omalizumab and placebo group, respectively. At Week 4 (after the first treatment), the least squares mean difference in the AE‐QoL and DLQI score between groups was −17.6 (P < .001) and −7.2 (P < .001), respectively. Significant QoL improvements in the omalizumab vs placebo groups continued until Week 28, but returned to placebo levels at the follow‐up visit. The mean (SD) baseline 5‐item World Health Organization Well‐being Index was 10.0 (5.5, omalizumab) and 7.7 (5.3, placebo), which increased above the depression threshold (<13) from Week 4 and throughout with omalizumab but not placebo treatment. Compared to placebo, omalizumab was also associated with decreased fear of suffocation due to angioedema.

Conclusions

Our findings support omalizumab treatment in patients with severe H1‐antihistamine‐refractory CSU with angioedema.

An ABC of the Warning Signs of Hereditary Angioedema

Hereditary angioedema (HAE) with C1 inhibitor deficiency is a genetic disorder that clinically manifests with attacks of angioedema in the subcutaneous and submucosal tissues, mainly in the extremities, abdomen, and upper airway. During attacks, vascular permeability is increased due to increased bradykinin (BK). This means that special therapies are needed for attacks that do not respond to traditional antiallergic therapies involving antihistamines, corticosteroids, and epinephrine. The recurring attacks may disable patients and lead to frequent visits to emergency rooms where misdiagnoses are common. HAE attacks may be fatal when upper-airway edema occurs, if proper treatment with a C1 inhibitor concentrate or BK receptor antagonist is not administered or an emergency tracheostomy is not performed. We propose a mnemonic method for the warning signs of HAE for the use as a diagnostic tool, i.e., the so-called "ABC" of the warning signs of HAE. The letters represent the following: A = Angioedema, B = Bradykinin, C = C1 inhibitor, D = Distress factors, E = Epinephrine nonresponsive, F = Family history, and G = Glottis/Gastrointestinal edema. To avoid fatalities, medical staff and patients, including family members, must be aware of HAE. An alphabetical mnemonic method has been developed and we hope it may benefit patients.

The Icatibant Outcome Survey: treatment of laryngeal angioedema attacks

Objective

To characterize the management and outcomes of life-threatening laryngeal attacks of hereditary angioedema (HAE) treated with icatibant in the observational Icatibant Outcome Survey (NCT01034969) registry.

Methods

This retrospective analysis was based on data from patients with HAE type I/II who received healthcare professional-administered or self-administered icatibant to treat laryngeal attacks between September 2008 and May 2013.

Results

Twenty centers in seven countries contributed data. Overall, 42 patients with HAE experienced 67 icatibant-treated laryngeal attacks. Icatibant was self-administered for 62.3% of attacks (healthcare professional-administered, 37.7%). One icatibant injection was used for 87.9% of attacks, with rescue or concomitant medication used for 9.0%. The median time to treatment was 2.0 h (n=31 attacks) and the median time to resolution was 6.0 h (n=35 attacks).

Conclusions

This analysis describes successful use of icatibant for the treatment of laryngeal HAE attacks in a real-world setting.

Using the Nursing Process to Identify and Treat Angioedema: A Case Study

The nursing process is the essential core of practice for registered nurses, independent of what field of nursing you have chosen. You learn it in nursing school and use it until you are no longer practicing. It is designed to train nurses how to develop a nursing care plan through critical thinking. Over the years it becomes a routine way of problem solving, but it is sometimes good to go back to the basics to remember the ground work. The focus of this article is to review the steps of the nursing process when faced with a complication, using our critical thinking skills.

Angioedema in the emergency department: a practical guide to differential diagnosis and management

Background

Angioedema is a common presentation in the emergency department (ED). Airway angioedema can be fatal; therefore, prompt diagnosis and correct treatment are vital.

Objective of the review

Based on the findings of two expert panels attended by international experts in angioedema and emergency medicine, this review aims to provide practical guidance on the diagnosis, differentiation, and management of histamine- and bradykinin-mediated angioedema in the ED.

Review

The most common pathophysiology underlying angioedema is mediated by histamine; however, ED staff must be alert for the less common bradykinin-mediated forms of angioedema. Crucially, bradykinin-mediated angioedema does not respond to the same treatment as histamine-mediated angioedema. Bradykinin-mediated angioedema can result from many causes, including hereditary defects in C1 esterase inhibitor (C1-INH), side effects of angiotensin-converting enzyme inhibitors (ACEis), or acquired deficiency in C1-INH. The increased use of ACEis in recent decades has resulted in more frequent encounters with ACEi-induced angioedema in the ED; however, surveys have shown that many ED staff may not know how to recognize or manage bradykinin-mediated angioedema, and hospitals may not have specific medications or protocols in place.

Conclusion

ED physicians must be aware of the different pathophysiologic pathways that lead to angioedema in order to efficiently and effectively manage these potentially fatal conditions.

Current and future therapies for the treatment of histamine-induced angioedema

INTRODUCTION

Angioedema, a sudden, self-limited swelling of localized areas of any part of the body that may or may not be associated with urticaria, is thought to be the result of a mast-cell mediated process versus a bradykinin etiology. Understanding the mechanism is key in determining the proper treatment. Areas Covered: Clinical presentation of varying angioedema types may be similar; however, the appropriate treatment algorithm is dependent upon clinicians' knowledge of the underlying pathophysiology and classification of angioedema. Literature review of recent guidelines, available medications, and alternative therapies was completed to provide an overview of options.

CONCLUSION

There are no formal guidelines for treatment of acute or chronic histamine-mediated angioedema, and therefore, algorithms for the treatment of acute and chronic urticaria should be followed until such information becomes available. Differentiating histamine-mediated versus bradykinin mediated angioedema is essential, as treatments and treatment responses are quite different. Further research is needed to better understand idiopathic angioedema that is unresponsive to H1/H2 antagonists, LTMAs, or medications designed to treat bradykinin-mediated angioedema.

A case report: Nursing interventions on a patient with anaphylactic shock in ICU

INTRODUCTION AND OBJECTIVES

The care plan of a 42-year-old woman with anaphylactic shock, secondary to ingestion of amoxicillin/clavulanic acid, with upper airway involvement due to laryngeal angioedema, is presented. Previously she had had two episodes of angioedema of unknown origin. The incidence of this phenomenon is between 3.2 and 10 cases/100,000 people/year.

CLINICAL OBSERVATION

An evaluation was made and three altered necessities stood out: breathing and circulation (she needed mechanical ventilation and noradrenalin perfusion), elimination (she required furosemide to keep an acceptable diuresis time), and hygiene and skin protection (she presented generalised hyperaemia, lip, lingual and oropharyngeal oedema). The hospital's Clinical Research Ethics Committee requested the patient's informed consent to access her clinical history.

INTERVENTIONS

According to the altered necessities, seven diagnoses were prioritised according to NANDA taxonomy: risk of allergic response, risk of infection, risk of ineffective renal perfusion, decreased cardiac output, impaired spontaneous ventilation, risk of unstable blood glucose level, and risk of dysfunctional gastrointestinal motility.

DISCUSSION AND CONCLUSIONS

Scores of outcome criteria showed a favourable evolution after 24hours. The development of a standardised NANDA-NOC-NIC language in the clinical case presented allowed us to organise the nursing work, facilitating recording and normalising clinical practice. As a limitation of this case, we didn't have serial plasma levels of histamine and tryptase to assess the evolution of anaphylactic symptoms. Highlight the importance of health education in a patient with a history of angioedema.

The burden of angioedema on United States emergency departments: 2006-2010

OBJECTIVES/HYPOTHESIS

Angioedema (AE) is a condition that may prompt a visit to an emergency department (ED), and can quickly progress to airway obstruction. To optimize treatment of AE, it is necessary to understand epidemiology and practice patterns. This study measured the magnitude of AE ED visits and characterized demographics, management, frequency of airway interventions, and mortality.

STUDY DESIGN

Analysis of two national data sets.

METHODS

From the Nationwide Emergency Department Sample and National Hospital Ambulatory Medical Care Survey, we identified all patients presenting from 2006 to 2010 with a primary diagnosis of AE, characterized by the International Classification of Diseases, Ninth Edition, Clinical Modification code 995.1. The discharges were weighted and stratified by comorbidities, age, treatments, and region. χ² , t test, and linear regression were employed for comparisons.

RESULTS

Total discharges increased from 87,481 (29.3 of 100,000 people) to 111,116 (35.8 of 100,000 people). More females were afflicted (57%), and 41.1% were African American. The majority (83%) of patients were discharged from the ED. Twelve percent of cases were attributed to antihypertensive adverse reaction, and these patients were older (P < .0001, odds ratio [OR] = 1.02), and had more comorbidities (P < .0001, OR = 5.66), hospital admissions (P < .0001, OR = 4.83), and intubations (P < .03, OR = 2.07). Overall, patients required intubation infrequently (<1%) and mortality was low (0.08%).

CONCLUSIONS

The AE burden on EDs has increased over time. Patients with adverse reactions to antihypertensives are older, have more comorbidities, and require admission and intubation more frequently. Further investigation is needed to better delineate causation and outcome predictors, and to understand regional practice variance.

LEVEL OF EVIDENCE

2c. Laryngoscope, 127:828-834, 2017.

Angioedema: Classification, management and emerging therapies for the perioperative physician

Angioedema is a rare condition which manifests as sudden localised, non-pitting swelling of certain body parts including skin and mucous membranes. It is vital that anaesthesiologists understand this condition, as it may present suddenly in the perioperative period with airway compromise. To identify literature for this review, the authors searched the PubMed, Medline, Embase, Scopus and Web of Science databases for English language articles covering a 10-year period, 2006 through 2016. Angioedema can be either mast-cell mediated or bradykinin-induced. Older therapies for histaminergic symptoms are well known to anaesthesiologists (e.g., adrenaline, anti-histamines and steroids), whereas older therapies for bradykinin-induced symptoms include plasma and attenuated androgens. New classes of drugs for bradykinin-induced symptoms are now available, including anti-bradykinin, plasma kallikrein inhibitor and C1 esterase inhibitors. These can be used prophylactically or as rescue medications. Anaesthesiologists are in a unique position to coordinate perioperative care for this complex group of patients.

Angioimmunoblastic T Cell Lymphoma Mimicking Chronic Urticaria

Angioimmunoblastic T cell lymphoma (AITL) is a rare but distinct type of T cell lymphoma with an aggressive course and high mortality. Most patients are diagnosed late in the disease and usually present with generalized lymphadenopathy. A minority have skin lesions at the time of diagnosis, more commonly in the form of nonspecific maculopapular rash with or without pruritus. We report a rare case of AITL presenting with chronic, recurrent angioedema and urticaria-like lesions and no palpable peripheral adenopathy. Primary Care physicians, dermatologists, and allergists must maintain a high index of suspicion for cutaneous manifestations of lymphoma, especially if the skin lesions are refractory to standard treatment. Timely diagnosis is essential to improve survival.

Lingual angioedema after alteplase treatment in a patient with acute ischemic stroke

BACKGROUND

In recent years, thrombolytic therapy has become the main treatment of ischemic stroke. But the increasing use of alteplase in ischemic stroke has made some complications more evident. Angioedema is a rare but potentially life-threatening complication of alteplase treatment. Only a few studies have examined the incidence of angioedema after treatment with alteplase for stroke.

METHODS

A 75-year-old man complaining of right hemiparesis was admitted to our emergency department. He was diagnosed as having acute ischemic stroke, and alteplase infusion was given two hours after the onset of stroke symptoms. Immediately after the completion of infusion he was noted to have a large swollen tongue.

RESULTS

His neurological symptoms resolved gradually within 4 hours, whereas his upper extremity strength improved to 4/5 and lower extremity 5/5. Lingual edema resolved within 16 hours without any complication. He died from presumed nosocomial infection 5 days later.

CONCLUSIONS

Lingual angioedema may appear as a possible complication in patients who were treated with alteplase. The management of these patients should be very careful.

Clinical similarities among bradykinin-mediated and mast cell-mediated subtypes of non-hereditary angioedema: a retrospective study

Background

Non-hereditary angioedema (non-HAE) is characterized by local swelling due to self-limiting, subcutaneous or submucosal extravasation of fluid, and can be divided into three subtypes. These subtypes are believed to have different pathophysiological backgrounds and are referred to in recent guidelines as bradykinin-mediated (e.g. caused by angiotensin-converting-enzyme-inhibitors), mast cell-mediated (e.g. angioedema with wheals) or idiopathic (cause unknown). Bradykinin-mediated subtypes are more closely related to hereditary angioedema than the other forms. Because clinical features of these non-HAE subtypes have not been studied in detail, we have looked at the clinical characteristics of symptoms and potential differences in clinical presentation of bradykinin-mediated and mast cell-mediated angioedema (AE) subtypes.

Methods

A questionnaire was sent to patients presenting with AE at our tertiary outpatient clinic to document clinical characteristics, potential triggers and location of AE. The severity of AE attacks was analysed using visual analogue scales (VAS).

Results

The questionnaire was returned by 106 patients, of which 104 were included in the analysis. AE with wheals, idiopathic AE, and drug-associated AE occurred in 64 (62%), 25 (24%) and 15 patients (14%) respectively. Most patients (62%) reported prodromal symptoms while 63% reported multiple locations for an attack. Face and oropharynx were the main locations of AE attacks of any subtype while swelling was the symptom most frequently reported as severe. Overall severity of the last attack was indicated as severe by 68% of the patients. There were no differences between the subgroups.

Conclusion

This similarity in clinical presentation raises the possibility that ACEi-induced, mast cell-mediated and idiopathic AE share common pathways.

Electronic supplementary material

The online version of this article (doi:10.1186/s13601-015-0049-8) contains supplementary material, which is available to authorized users.

Effectiveness of ecallantide in treating angiotensin-converting enzyme inhibitor-induced angioedema in the emergency department

BACKGROUND

Angiotensin-converting enzyme inhibitor-induced angioedema (ACEI-AE) is mediated by bradykinin. There remains an unmet treatment need because these patients, when presenting to the emergency department (ED), do not respond to conventional therapies, such as antihistamines and corticosteroids.

OBJECTIVE

To estimate the treatment effect of ecallantide, a recombinant plasma kallikrein inhibitor, in ED patients with ACEI-AE in whom conventional therapy fails.

METHODS

This was a triple-blind (patient, physician, and statistician), randomized, controlled, phase 2 study to estimate the magnitude of safety and efficacy signals for designing a definitive phase 3 trial comparing conventional therapy with ecallantide to conventional therapy with placebo. Patients were enrolled from April 1, 2010, through January 31, 2013. The primary efficacy study end point was achieving discharge criteria from the ED within 4 hours after initiating study-related treatment.

RESULTS

Discharge criteria from the ED was met in 4 hours or less for 8 (31%) of 26 patients receiving ecallantide vs 5 of (21%) 24 patients receiving placebo (difference in proportions, 10%; 95% confidence interval, -14% to 34%). Ecallantide was well tolerated in both groups.

CONCLUSION

The results from this preliminary study reveal that ecallantide is safe to use and may increase the proportion of patients who meet early discharge criteria by approximately10%. A larger phase 3 study is necessary to confirm the efficacy and evaluate the cost-effectiveness of ecallantide use for ACEI-AE in the ED setting.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01036659.