Demographic and clinical characteristics of patients with hereditary angioedema in Canada.

BACKGROUND: Data on the clinical and demographic features of Canadian patients with hereditary angioedema (HAE) are lacking. OBJECTIVE: To describe the clinical and demographic features in a large Canadian HAE cohort and compare them with patients with HAE in other countries. METHODS: An online questionnaire was distributed to the members of 2 Canadian HAE patient groups to collect information on demographics and HAE clinical characteristics. All participants 18 years of age or older with HAE type I or II were eligible. Frequency, location, prodromes, and triggers of HAE attacks, including types of HAE treatment, were characterized. RESULTS: Among the 90 participants who completed the online survey, 57% self-identified as having HAE type 1 and 26% HAE type II. The average diagnostic delay was 11 years. In the preceding 6 months, 24% of the participants had no attacks and 35% experienced greater than 5 attacks. The most frequently affected regions of the body were the abdomen (83%), arms orlegs (63%), face (41%), and larynx or throat (41%). Approximately 87% of the participants reported having access to C1 inhibitor at home, and 69% reported using it for long-term prophylaxis. CONCLUSION: Canadian patients with HAE share common clinical characteristics with patients with HAE in other countries. They had a delay in HAE diagnosis and a high burden of disease, as indicated by the high frequency of attacks in the preceding 6 months. This study provides a better understanding of the demographic and clinical characteristics of Canadian patients with HAE.

Quality of life in patients with hereditary angioedema in Canada.

BACKGROUND: Hereditary angioedema (HAE) is associated with decreased quality of life (QoL), which has typically been measured using a generic non-disease-specific questionnaire. OBJECTIVE: We aimed to assess the QoL in patients with HAE type I and II in Canada using a previously validated HAE-specific questionnaire. METHODS: An online questionnaire was sent to the members of two Canadian HAE patient groups to collect data on demographics, HAE clinical course, and QoL scores. All patients 18 years of age or older with HAE type I or II were eligible. The impact of the available clinical factors on the QoL scores was evaluated. Multiple linear regression was performed using clinically relevant factors to predict HAE QoL outcome. RESULTS: Among the 72 patients in the study, the mean total HAE QoL score was 102 (±23) (SD) on a scale of 25 to 135, with higher scores indicating better QoL. Although the total QoL scores correlated positively with patients' level of satisfaction and perceived control (P < .001 for both), it correlated negatively with the number of acute attacks (P = .03). Yet, the types of treatment did not have an impact on the QoL. Predictors, including sex, comorbidities, and the number of attacks, only explained 12% of the variance in the total QoL scores. CONCLUSION: HAE continues to impair QoL in Canadian patients despite receiving recommended treatment. Although the frequency of attacks affects QoL, patients' experience with their HAE care also affects QoL substantially. The study highlights the importance of considering patients' experience with their HAE care as physicians develop an appropriate management plan.

RAPID DESENSITIZATION WITH INTRAVENOUS INSULIN IN A PATIENT WITH DIABETIC KETOACIDOSIS AND INSULIN ALLERGY.

OBJECTIVE: We report a case of insulin desensitization in a patient with known allergy to multiple insulin preparations who presented with diabetic ketoacidosis (DKA). METHODS: Clinical and laboratory data, and desensitization protocols are presented. RESULTS: A 65-year-old woman with type 2 diabetes and a documented insulin allergy presented with severe DKA. She was managed initially with intravenous (IV) fluids, sodium bicarbonate, and hemodialysis. An intradermal skin test was positive for 0.01 units/mL of human regular insulin. A rapid desensitization protocol for IV human regular insulin was initiated after pretreatment with methylprednisolone, ranitidine, montelukast, and cetirizine. An initial dilution of 1 unit of insulin in 100,000 mL of 0.9% sodium chloride was started at 5 mL/hour IV. The dilution was increased at 60-minute intervals to 1 unit/10,000 mL, 1 unit/1,000 mL, 1 unit/100 mL, 1 unit/10 mL, then 1 unit/1 mL. The dose was then increased from 1 to 7 units/hour (0.1 units/kg body weight/hour). The anion gap closed after 24 hours, and overlapping desensitization was started for subcutaneous (SC) human regular insulin starting with 0.00001 units with a gradual increase to 7 units before meals and 6 units at bedtime over 5 days. There were no anaphylactic reactions to IV or SC insulin. She was discharged with human regular insulin SC 4 times daily, oral montelukast, cetirizine, diphenhydramine as needed, and an epinephrine pen. No allergic reactions were reported at follow-up visits. CONCLUSION: Rapid insulin desensitization is possible to allow treatment of DKA with human regular insulin IV in patients with known insulin allergy.

A rare case of anaphylaxis to Indian jujube (Ziziphus Mauritiana Lam).

BACKGROUND: Indian jujube (Ziziphus Mauritiana Lam) is a sweet fruit from a tree native to tropical and subtropical regions of Asia and India. A few case reports have implicated Indian jujube to cause latex-fruit syndrome. We present the first case of an anaphylactic reaction to this fruit in a patient with no latex allergy. CASE PRESENTATION: A 55-year-old male was referred to the Outpatient Allergy Clinic at Queen's University for evaluation of anaphylaxis caused by ingestion of Indian jujube. He presented to the Emergency Department (ED) with scalp pruritus, dyspnea and generalized urticaria, which occurred two hours after he had consumed a homemade candied fruit cocktail consisting of Indian jujube, water, Thai and Indian sweetener. In the ED, he was treated with epinephrine, intravenous diphenhydramine and steroids. He did not have any previous history of environmental or food allergies but had consumed this fruit frequently since childhood. In clinic, he underwent skin-prick testing with a saline slurry of candied jujube, which resulted in a positive wheal and flare response with appropriate controls. On subsequent visit, skin-prick tests were performed with saline slurries of the Thai and Indian sweetener used to make the cocktail. Both tests were negative when applied to a healthy volunteer. Skin-prick testing to latex allergen and latex specific IgE were both negative. He was diagnosed with an IgE-mediated anaphylactic reaction to the Indian jujube fruit. He was advised to avoid consumption of Indian jujubes and carry an epinephrine autoinjector. CONCLUSIONS: Anaphylaxis secondary to Indian jujube ingestion is an extremely rare phenomenon in patients without a latex allergy. A possible allergy to Indian jujube should be taken into consideration when working up anaphylaxis, especially in patient of Asian and Indian descent who have ceased regular consumption of the fruit.

Correction to: The International/Canadian Hereditary Angioedema Guideline.

[This corrects the article DOI: 10.1186/s13223-019-0376-8.].

Development of the Hereditary Angioedema Rapid Triage Tool.

BACKGROUND: Patients with hereditary angioedema (HAE) present to the emergency department (ED), where their symptoms are often incorrectly attributed to common allergic and gastrointestinal conditions, resulting in major delays in diagnosis and treatment. OBJECTIVE: To develop a rapid triage HAE (Hereditary AngioEdema Rapid Triage [HAE-RT]) tool for ED settings. METHODS: A mixed-methods approach was used in 3 phases: Phase 1: A literature review on the current management of patients with HAE in the ED. Phase 2: A Delphi study with HAE specialists (N = 9) and Patient Advocacy Group Members (N = 3) to reach consensus on the predictor variables (PVs) to be included in the HAE-RT tool. Phase 3: A retrospective chart review to assess the performance of the PVs for HAE. RESULTS: The literature review informed the final list of PVs included in the HAE-RT prototype. Nine experts participated in the Delphi study. Of 8 identified HAE-specific PVs, 3 reached consensus: (1) absence of urticaria, (2) recurrent abdominal pain/swelling, and (3) lack of response to allergic-directed therapy. The retrospective study included 107 patients (N = 66 with HAE; N = 41 non-HAE). Patients with HAE were more likely to have a family history of HAE (71%; P < .0001), previous recurrent angioedema (96%; P < .002), and previous recurrent abdominal pain (77%; P < .0001), and only 6% responded to allergy treatments (P < .0001). The HAE-RT tool had 98% sensitivity and specificity. CONCLUSIONS: Expert consensus led to the identification and prioritization of variables that when incorporated into an HAE-RT tool were associated with a high level of sensitivity and specificity when applied to known patients.

The International/Canadian Hereditary Angioedema Guideline.

This is an update to the 2014 Canadian Hereditary Angioedema Guideline with an expanded scope to include the management of hereditary angioedema (HAE) patients worldwide. It is a collaboration of Canadian and international HAE experts and patient groups led by the Canadian Hereditary Angioedema Network. The objective of this guideline is to provide evidence-based recommendations, using the GRADE system, for the management of patients with HAE. This includes the treatment of attacks, short-term prophylaxis, long-term prophylaxis, and recommendations for self-administration, individualized therapy, quality of life, and comprehensive care. New to the 2019 version of this guideline are sections covering the diagnosis and recommended therapies for acute treatment in HAE patients with normal C1-INH, as well as sections on pregnant and paediatric patients, patient associations and an HAE registry. Hereditary angioedema results in random and often unpredictable attacks of painful swelling typically affecting the extremities, bowel mucosa, genitals, face and upper airway. Attacks are associated with significant functional impairment, decreased health-related quality of life, and mortality in the case of laryngeal attacks. Caring for patients with HAE can be challenging due to the complexity of this disease. The care of patients with HAE in Canada, as in many countries, continues to be neither optimal nor uniform. It lags behind some other countries where there are more organized models for HAE management, and greater availability of additional licensed therapeutic options. It is anticipated that providing this guideline to caregivers, policy makers, patients, and advocates will not only optimize the management of HAE, but also promote the importance of individualized care. The primary target users of this guideline are healthcare providers who are managing patients with HAE. Other healthcare providers who may use this guideline are emergency and intensive care physicians, primary care physicians, gastroenterologists, dentists, otolaryngologists, paediatricians, and gynaecologists who will encounter patients with HAE and need to be aware of this condition. Hospital administrators, insurers and policy makers may also find this guideline helpful.

The diagnosis of hereditary angioedema with C1 inhibitor deficiency: a survey of Canadian physicians and laboratories.

BACKGROUND: Hereditary angioedema due to C1 inhibitor deficiency (C1-INH-HAE) is an autosomal dominant disease resulting in random and unpredictable attacks of swelling. The swelling in C1-INH-HAE is a result of impaired regulation of bradykinin production. The fact that the array of tests needed to diagnose HAE is not always available to the treating physicians is challenging for them and their patients. METHODS: The data for this article were extracted from two distinct surveys. The first survey was conducted among HAE treating physicians and aimed to determine the availability and utilization of the various assays performed to help the diagnosis of C1-INH-HAE. The second survey was conducted with the various laboratories across Canada that performs the assays used in the diagnosis of HAE. The aim of this survey was to determine the availability and profile of the various assays used in the diagnosis of C1-INH-HAE in Canada, thereby ultimately bringing a rational basis for the biological testing. RESULTS: C1-INH functional assay was widely available in Canada (93%), but was only offered by a small numbers of hospitals meaning that there could be longer delays in the analysis of these samples that may explain why the physicians expressed a lower level of confidence in this assay (59%). Antigenic C1-INH was available to the vast majority of the physicians treating C1-INH-HAE (93%) and was considered reliable by 96% of the respondents. Antigenic C4 was found available to all Canadian physicians and, although with limited specificity, was considered very reliable by all the participants. This study revealed that 81% of physicians were able to order the antigenic C1q and the confidence in this assay was moderate (70%). Concerning genetic testing, the survey revealed that most of the CHAEN members never had to or couldn't order this test. CONCLUSION: This study highlights the need for improved education and knowledge exchange, about biological assays available to Canadian physicians and their performance in proper diagnosis of C1-INH-HAE to improve confidence and access to relevant tests.

ACE-I Angioedema: Accurate Clinical Diagnosis May Prevent Epinephrine-Induced Harm.

INTRODUCTION: Upper airway angioedema is a life-threatening emergency department (ED) presentation with increasing incidence. Angiotensin-converting enzyme inhibitor induced angioedema (AAE) is a non-mast cell mediated etiology of angioedema. Accurate diagnosis by clinical examination can optimize patient management and reduce morbidity from inappropriate treatment with epinephrine. The aim of this study is to describe the incidence of angioedema subtypes and the management of AAE. We evaluate the appropriateness of treatments and highlight preventable iatrogenic morbidity. METHODS: We conducted a retrospective chart review of consecutive angioedema patients presenting to two tertiary care EDs between July 2007 and March 2012. RESULTS: Of 1,702 medical records screened, 527 were included. The cause of angioedema was identified in 48.8% (n=257) of cases. The most common identifiable etiology was AAE (33.1%, n=85), with a 60.0% male predominance. The most common AAE management strategies included diphenhydramine (63.5%, n=54), corticosteroids (50.6%, n=43) and ranitidine (31.8%, n=27). Epinephrine was administered in 21.2% (n=18) of AAE patients, five of whom received repeated doses. Four AAE patients required admission (4.7%) and one required endotracheal intubation. Epinephrine induced morbidity in two patients, causing myocardial ischemia or dysrhythmia shortly after administration. CONCLUSION: AAE is the most common identifiable etiology of angioedema and can be accurately diagnosed by physical examination. It is easily confused with anaphylaxis and mismanaged with antihistamines, corticosteroids and epinephrine. There is little physiologic rationale for epinephrine use in AAE and much risk. Improved clinical differentiation of mast cell and non-mast cell mediated angioedema can optimize patient management.

Canadian hereditary angioedema guideline.

Hereditary angioedema (HAE) is a disease which is associated with random and often unpredictable attacks of painful swelling typically affecting the extremities, bowel mucosa, genitals, face and upper airway. Attacks are associated with significant functional impairment, decreased Health Related Quality of Life, and mortality in the case of laryngeal attacks. Caring for patients with HAE can be challenging due to the complexity of this disease. The care of patients with HAE in Canada is neither optimal nor uniform across the country. It lags behind other countries where there are more organized models for HAE management, and where additional therapeutic options are licensed and available for use. The objective of this guideline is to provide graded recommendations for the management of patients in Canada with HAE. This includes the treatment of attacks, short-term prophylaxis, long-term prophylaxis, and recommendations for self-administration, individualized therapy, quality of life, and comprehensive care. It is anticipated that by providing this guideline to caregivers, policy makers, patients and their advocates, that there will be an improved understanding of the current recommendations regarding management of HAE and the factors that need to be considered when choosing therapies and treatment plans for individual patients. The primary target users of this guideline are healthcare providers who are managing patients with HAE. Other healthcare providers who may use this guideline are emergency physicians, gastroenterologists, dentists and otolaryngologists, who will encounter patients with HAE and need to be aware of this condition. Hospital administrators, insurers and policy makers may also find this guideline helpful.

Prognostic factors in outcome of angioedema in the emergency department.

Angioedema is a transient, localized swelling caused by two distinct mechanisms, mediated by histamine and bradykinin, respectively, although a proportion of cases remain idiopathic. Studies that characterize undifferentiated angioedema presenting in emergency departments (EDs) are limited. This study investigates the presentation patterns of undifferentiated angioedema in the ED based on the presumed mechanism of swelling. Medical records from all ED visits to two tertiary care hospitals from July 2007 to March 2012 were electronically reviewed. Records with documented visible swelling on general inspection and/or fiberoptic laryngoscopy and a diagnostic code for anaphylactic shock, angioneurotic edema, allergy unspecified, defects in the complement system, or unspecified drug adverse effects were included. Demographic, clinical, and outcome data were collected via a standardized form. Data were analyzed descriptively, including frequencies and percentages for categorical data and means and SDs for continuous data. Predictors for admission were identified using multivariate logistic regression models. ED records from 527 visits for angioedema by 455 patients were included in the study. Annual rate of angioedema was 1 per 1000 ED visits. Urticaria was associated with peripheral (p = 0.008) and lip angioedema (p = 0.001), and the absence of urticaria correlated with tongue angioedema (p = 0.001) and trended toward correlation with pharyngeal angioedema (p = 0.056). Significant predictors of admission included nonsteroidal anti-inflammatory drug-induced angioedema (odds ratio [OR], 15.3), epinephrine treatment (OR, 8.34), hypotension (OR, 15.7), multiple-site angioedema (OR, 4.25), and pharyngeal (OR, 1.23) and tongue angioedema (OR, 4.62). Concomitant urticaria was associated with a significant longer stay in the ED (p < 0.001). The presence of urticaria correlated with the location of angioedema, need for airway management, length of ED visit, and recurrence. A detailed drug and family history, screening blood work for C1 esterase inhibitor deficiency when indicated, and prompt management of angioedema based on presumed mechanism of swelling are crucial steps in managing undifferentiated angioedema in ED.

A case of anaphylaxis to peppermint.

BACKGROUND: Anaphylaxis, a form of IgE mediated hypersensitivity, arises when mast cells and possibly basophils are provoked to secrete mediators with potent vasoactive and smooth muscle contractile activities that evoke a systemic response. We report a case of IgE mediated anaphylaxis to peppermint (Mentha piperita) in a male shortly after sucking on a candy. CASE PRESENTATION: A 69 year old male developed sudden onset of lip and tongue swelling, throat tightness and shortness of breath within five minutes of sucking on a peppermint candy. He denied lightheadedness, weakness, nausea, vomiting, or urticaria. He took 25 mg of diphenhydramine, but his symptoms progressed to onset of cough, wheeze and difficulty with talking and swallowing. He was rushed to the nearest emergency department, where he was treated with intramuscular epinephrine, antihistamines and steroids. On history, he reported recent onset of mouth itchiness and mild tongue and lip swelling after using Colgate peppermint toothpaste. He denied previous history of asthma, allergic rhinitis, food or drug allergies. His past medical history was remarkable for hypercholesterolemia, gastroesophageal reflux and gout. He was on simvastatin, omeprazole, aspirin, and was carrying a self-injectable epinephrine device. He moved to current residence three years ago and cultivated mint plants in his backyard. He admitted to develop nasal congestion, cough and wheeze when gardening. Physical examination was unremarkable apart from slightly swollen pale inferior turbinates. Skin prick test (SPT) was strongly positive to a slurry of peppermint candy and fresh peppermint leaf, with appropriate controls. Same tests performed on five healthy volunteers yielded negative results. Skin testing to common inhalants including molds and main allergenic foods was positive to dust mites. Strict avoidance of mint containing items was advised. Upon reassessment, he had removed mint plants from his garden which led to resolution of symptoms when gardening. CONCLUSION: IgE mediated anaphylaxis to peppermint is rare. This case demonstrates a systemic reaction to a commonly consumed item, incapable of triggering anaphylaxis in the far majority of the population, yet causing a severe episode for our patient.

Cardiac rhythm device contact dermatitis.

We present a series of three cases of patch testing confirmed cardiac rhythm device induced contact dermatitis. In the first two cases, there was complete resolution with device extraction and reimplantation with another device with either an absence of the offending agent or a coating with another resin or metal. These cases illustrate the difficulties in diagnosing pain, tenderness, and dermatological manifestations in patients with cardiac rhythm devices (pacemakers and implantable cardioverter defibrillators).

DRESS with delayed onset acute interstitial nephritis and profound refractory eosinophilia secondary to Vancomycin.

BACKGROUND: Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) is a relatively rare clinical entity; even more so in response to vancomycin. METHODS: Case report. RESULTS: We present a severe case of vancomycin-induced DRESS syndrome, which on presentation included only skin, hematological and mild liver involvement. The patient further developed severe acute interstitial nephritis, eosinophilic pneumonitis, central nervous system (CNS) involvement and worsening hematological abnormalities despite immediate discontinuation of vancomycin and parenteral corticosteroids. High-dose corticosteroids for a prolonged period were necessary and tapering of steroids a challenge due to rebound-eosinophilia and skin involvement. CONCLUSION: Patients with DRESS who are relatively resistant to corticosteroids with delayed onset of certain organ involvement should be treated with a more prolonged corticosteroid tapering schedule. Vancomycin is increasingly being recognized as a culprit agent in this syndrome.

Monitoring of peanut-allergic patients with peanut-specific IgE.

Peanut allergy affects approximately 1% of the population. Double-blind placebo-controlled food challenges are gold standard for diagnosis. Serum peanut-specific IgE (PN-IgE) is used in clinical practice as an additional diagnostic and monitoring tool. The purpose of this study was to characterize the clinical features of a peanut-allergic patient's cohort and determine the optimum frequency of measuring PN-IgE to predict the outcome of future peanut challenges. Retrospective chart review was performed of peanut-allergic patients followed up and serially tested for PN-IgE with a qualitative antibody fluorescent-enzyme immunoassay performed at the Immunology Laboratory, London Health Sciences Center, from 1997 to 2004. One hundred eighteen patients (median age at first reaction to peanut, 1.5 years; median baseline PN-IgE, 18.75) were reviewed. Younger age at first reaction and first PN-IgE measurement predicted slower decline of PN-IgE values (p < 0.001 and p = 0.044). At 2 and 5 years post-initial measurement, 12.9 and 66%, respectively, of all patients had a significant decrease of PN-IgE values. Twenty percent of the patients experienced elevation of PN-IgE levels during follow-up. For most patients with significant history of reaction to peanuts and positive skin-prick test, it is probably adequate to measure serum PN-IgE levels every 3-5 years to screen for development of tolerance and predict the outcome of future peanut challenges. More frequent measurements might be considered in older patients with lower initial PN-IgE levels.