UCOMB-real life data: treatment strategies for chronic urticaria patients with comorbidities

BACKGROUND

There is a lack of real-life safety data on treatment options for chronic urticaria in the presence of comedication and comorbidities.

METHODS

We present a single-center UCARE pilot study of 212 outpatients with chronic urticaria. Patients were divided into three groups according to different CU therapies according to international guidelines.

RESULTS

Of 212 patients, 108 (mean age 48.9 years, 71.3% female) had 59 comorbidities, including cardiovascular, autoimmune and malignant diseases. Patients were followed for a mean of 24.6 months (SD ± 21.3). Urticaria therapies were divided into three groups: A: 105 (97.2%) with omalizumab and 2nd generation antihistamines), B: 16 patients (14.8%): dual therapy with antihistamines and cyclosporine in 10 (9.3%), montelukast in five (4. 6%), dapsone in four (3.7%), hydroxychloroquine in one patient (0.9%), C: 12 (11.1%) patients received a third drug for 4.9 months (SD ± 3.2) and one quadruple therapy (2.1 months). 10 out of 12 (83.3%) patients received montelukast, two (16.7%) cyclosporine, two (16.7%) dapsone and one (8.3%) hydroxychloroquine as a third drug for chronic urticaria.

CONCLUSIONS

Combining treatment modalities for chronic urticaria and comorbidities are available and feasible with a good safety profile.

BTK signaling-a crucial link in the pathophysiology of chronic spontaneous urticaria

Chronic spontaneous urticaria (CSU) is an inflammatory skin disorder that manifests with itchy wheals, angioedema, or both for more than 6 weeks. Mast cells and basophils are the key pathogenic drivers of CSU; their activation results in histamine and cytokine release with subsequent dermal inflammation. Two overlapping mechanisms of mast cell and basophil activation have been proposed in CSU: type I autoimmunity, also called autoallergy, which is mediated via IgE against various autoallergens, and type IIb autoimmunity, which is mediated predominantly via IgG directed against the IgE receptor FcεRI or FcεRI-bound IgE. Both mechanisms involve cross-linking of FcεRI and activation of downstream signaling pathways, and they may co-occur in the same patient. In addition, B-cell receptor signaling has been postulated to play a key role in CSU by generating autoreactive B cells and autoantibody production. A cornerstone of FcεRI and B-cell receptor signaling is Bruton tyrosine kinase (BTK), making BTK inhibition a clear therapeutic target in CSU. The potential application of early-generation BTK inhibitors, including ibrutinib, in allergic and autoimmune diseases is limited owing to their unfavorable benefit-risk profile. However, novel BTK inhibitors with improved selectivity and safety profiles have been developed and are under clinical investigation in autoimmune diseases, including CSU. In phase 2 trials, the BTK inhibitors remibrutinib and fenebrutinib have demonstrated rapid and sustained improvements in CSU disease activity. With phase 3 studies of remibrutinib ongoing, it is hoped that BTK inhibitors will present an effective, well-tolerated option for patients with antihistamine-refractory CSU, a phenotype that presents a considerable clinical challenge.

Airway Involvement and Intervention in Non-ACE-Inhibitor-Induced Angioedema

OBJECTIVES

Characterize the presentation of patients with non-angiotensin-converting enzyme inhibitor (ACEI)-induced angioedema and determine risk factors associated with patient disposition and possible need for airway intervention.

METHODS

The medical records of adult patients in the Emergency Department (ED) and diagnosed with non-ACEI-induced angioedema over 4.5 years were included. Demographics, vital signs, etiology, timeline, presenting symptoms, physical exam including flexible laryngoscopy, medical management, and disposition were examined. Statistical analyses were conducted using SPSS V 23.0 software calculating and comparing means, standard deviations, medians, and correlation of categorical and ordinate variables.

RESULTS

A total of 181 patients with non-ACEI-induced angioedema were evaluated with flexible laryngoscopy by otolaryngology. Notably, 11 patients (6.1%) required airway intervention and were successfully intubated. Statistically significant factors (p ≤ 0.05) associated with airway intervention included the diastolic blood pressure (DBP) and mean arterial pressure (MAP) (p = 0.006 and 0.01 respectively), symptoms of dysphonia (p = 0.018), the presence of oropharyngeal, supraglottic, and hypopharyngeal edema (p ≤ 0.001 for each site), and the number of edematous anatomic subsites documented on physical exam (p < 0.001). Other patient demographics, prior history of angioedema, heart rate, systolic blood pressure, symptom onset, number of symptoms at presentation, and medication administered in the ED did not correlate with airway intervention.

CONCLUSION

Dysphonia, DBP, MAP, anatomic location of edema and edema in multiple sites are associated with airway intervention and a higher level of care in non-ACEI-induced angioedema and can be useful in risk assessment in patient management.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:2282-2287, 2024.

Hereditary angioedema with normal C1 inhibitor associated with carboxypeptidase N deficiency

Background

Hereditary angioedema (HAE) is a potentially life-threatening disorder characterized by recurrent episodes of subcutaneous or submucosal swelling. HAE with normal C1 inhibitor (HAE-nC1-INH) is an underdiagnosed condition. Although the association with genetic variants has been identified for some families, the genetic causes in many patients with HAE-nC1-INH remain unknown. The role of genes associated with bradykinin catabolism is not fully understood.

Objective

We sought to investigate the biological parameters and the genes related to kallikrein-kinin system in families with a clinical phenotype of HAE-nC1-INH and presenting with a carboxypeptidase N (CPN) deficiency.

Methods

This study includes 4 families presenting with HAE-nC1-INH and CPN deficiency. Patients' clinical records were examined, biological parameters of kallikrein-kinin system were measured, and genetics was analyzed by next-generation sequencing and Sanger sequencing. Predictive algorithms (Human Splicing Finder, Sorting Intolerant From Tolerant, Polymorphism Phenotyping v2, MutationTaster, and ClinPred) were used to classify variants as affecting splicing, as benign to deleterious, or as disease-causing.

Results

Patients presented with angioedema and urticaria, mainly on face/lips, but also with abdominal pain or laryngeal symptoms. Affected patients displayed low CPN activity-30% to 50% of median value in plasma. We identified 3 variants of the CPN1 gene encoding the catalytic 55-kDa subunit of CPN: c.533G>A, c.582A>G, and c.734C>T. CPN deficiency associated with genetic variants segregated with HAE-nC1-INH symptoms in affected family members.

Conclusions

CPN1 gene variants are associated with CPN deficiency and HAE-nC1-INH symptoms in 4 unrelated families. Genetic CPN deficiency may contribute to bradykinin and anaphylatoxin accumulation, with synergistic effects in angioedema and urticarial symptoms.

Meta-analysis of ACE inhibitor-induced angioedema identifies novel risk locus

BACKGROUND

Angioedema is a rare but potentially life-threatening adverse drug reaction in patients receiving angiotensin-converting enzyme inhibitors (ACEis). Research suggests that susceptibility to ACEi-induced angioedema (ACEi-AE) involves both genetic and nongenetic risk factors. Genome- and exome-wide studies of ACEi-AE have identified the first genetic risk loci. However, understanding of the underlying pathophysiology remains limited.

OBJECTIVE

We sought to identify further genetic factors of ACEi-AE to eventually gain a deeper understanding of its pathophysiology.

METHODS

By combining data from 8 cohorts, a genome-wide association study meta-analysis was performed in more than 1000 European patients with ACEi-AE. Secondary bioinformatic analyses were conducted to fine-map associated loci, identify relevant genes and pathways, and assess the genetic overlap between ACEi-AE and other traits. Finally, an exploratory cross-ancestry analysis was performed to assess shared genetic factors in European and African-American patients with ACEi-AE.

RESULTS

Three genome-wide significant risk loci were identified. One of these, located on chromosome 20q11.22, has not been implicated previously in ACEi-AE. Integrative secondary analyses highlighted previously reported genes (BDKRB2 [bradykinin receptor B2] and F5 [coagulation factor 5]) as well as biologically plausible novel candidate genes (PROCR [protein C receptor] and EDEM2 [endoplasmic reticulum degradation enhancing alpha-mannosidase like protein 2]). Lead variants at the risk loci were found with similar effect sizes and directions in an African-American cohort.

CONCLUSIONS

The present results contributed to a deeper understanding of the pathophysiology of ACEi-AE by (1) providing further evidence for the involvement of bradykinin signaling and coagulation pathways and (2) suggesting, for the first time, the involvement of the fibrinolysis pathway in this adverse drug reaction. An exploratory cross-ancestry comparison implicated the relevance of the associated risk loci across diverse ancestries.

Piperacillin-Tazobactam-Induced Urticaria and Angioedema: A Case Report With Literature Review

Drug-induced urticaria and angioedema cases are typically reversible upon discontinuation and can be triggered by antibiotics, angiotensin-converting enzyme inhibitors, or nonsteroidal anti-inflammatory drugs. Piperacillin-tazobactam, a common broad-spectrum antimicrobial, has been linked to severe adverse reactions, such as thrombocytopenia, hemolytic anemia, and Steven Johnson syndrome in some cases. A 35-year-old male presented to the emergency department with fever, cough, and acute breathlessness, complicating his ongoing treatment for pulmonary tuberculosis with bedaquiline and delamanid. He was admitted and received supportive care. On the third day of intravenous piperacillin-tazobactam, he developed drug-induced urticaria and angioedema, which resolved upon discontinuing the drug. Piperacillin/tazobactam-induced hypersensitivity reaction is an immunologic and IgE-mediated immediate reaction. IgE-mediated immediate reactions to three major phenotypes of allergic patients with confirmed to piperacillin/tazobactam are either (1) sensitized to the β-lactam ring or (2) sensitized to the lateral chain of aminopenicillins or (3) selective to piperacillin/tazobactam alone. A skin patch test is advised, or prescribed to avoid hypersensitivity reactions due to piperacillin/tazobactam. This case underscores the challenges of non-adherence to anti-tubercular therapy, leading to drug resistance and prolonged, costly, and sometimes intolerable treatments. Regular patient follow-up, counseling, monitoring, and healthcare provider involvement are essential to enhance treatment adherence. Adverse drug reactions must be promptly reported and managed, and patient-centric approaches are crucial. Digital patient records and standardized data collection are recommended for program evaluation and global policy development. Causality assessment for piperacillin-tazobactam was diagnosed as the probable cause of drug-induced urticaria and angioedema. This case highlights the importance of adherence to tuberculosis treatment to prevent drug resistance. Overall, patient-centered care, monitoring adverse events of drug added, and better data collection are crucial for successful tuberculosis management.

Deucrictibant for angioedema due to acquired C1-inhibitor deficiency: A randomized-controlled trial

BACKGROUND

Angioedema due to acquired C1-inhibitor deficiency is a very rare but serious disease, with an estimated prevalence of 1 per 500,000 persons. There are no approved therapies to treat or prevent angioedema swelling in patients with this condition. Deucrictibant is a specific, orally bioavailable, competitive antagonist of the bradykinin B2 receptor currently under investigation for hereditary angioedema.

OBJECTIVE

Our aim was to assess the efficacy and safety of deucrictibant as acute and prophylactic treatment for angioedema due to acquired C1-inhibitor deficiency.

METHODS

A 2-part, randomized, double-blind, placebo-controlled crossover study was conducted. In Part 1, 4 consecutive angioedema attacks were treated with 3 doses of deucrictibant (10 mg, 20 mg, and 30 mg) or placebo. In Part 2, deucricibant, 20 mg, or placebo was administered twice daily for 2 treatment periods of 8 weeks.

RESULTS

Three patients were enrolled; of those 3 patients, 1 completed both study parts and 2 completed only Part 2. In Part 1, a reduction in attack severity was observed in the 3 attacks treated with deucrictibant as opposed to an increase in severity of the attack treated with placebo. In Part 2, the individual mean monthly attack rates were 2.0, 0.6, and 1.0 during the placebo period and 0.0 across all patients during treatment with deucrictibant. There were no severe adverse events and 1 self-limiting treatment-emergent adverse event (abdominal pain).

CONCLUSIONS

Deucrictibant has the potential to effectively and safely treat and prevent angioedema attacks due to acquired C1-inhibitor deficiency.

Recurrent Isolated Uvular Angioedema Associated With Intranasal Cocaine Use: A Case Report

Isolated uvular angioedema, or Quincke's disease, is a rare manifestation with various potential causes. This article presents the first documented case of recurrent isolated uvular angioedema associated with intranasal cocaine use. The patient, a 43-year-old man, exhibited acute symptoms of sore throat, throat swelling, and difficulty breathing, with a history of a similar episode a few years prior. Both episodes occurred following intranasal cocaine use. Examination revealed an enlarged uvula obstructing the airway. The patient was treated with epinephrine, antihistamines, and corticosteroids with resolution of the uvular edema. This case highlights the importance of considering cocaine as a potential causative agent in isolated uvular angioedema and emphasizes the need for patient education to avoid further cocaine use.

Monitoring recurrent angioedema: Findings from the Turkish angioedema control test validation study

BACKGROUND

Determination of control level in recurrent angioedema (RAE) is necessary to guide management. Here, we validated a Turkish version of the angioedema control test (AECT) for 4-week (AECT-4wk) and for 3-month (AECT-3mth) and assessed their utility in monitoring RAE.

METHOD

The recommended structured translation process for patient-reported outcome measures was completed. The final versions were administered to 51 patients with mast cell-mediated angioedema (MMAE) and 38 patients with hereditary angioedema, and the minimal clinically important difference (MCID) was determined. Additionally, anchor surveys comprising angioedema activity score for 28 days (AAS-28 day), visual analog score for angioedema control, Likert scale for the control level from the patient's perspective (LS-AEC), angioedema quality of life, short form-12 (SF-12) and patients' assessment of treatment sufficiency were applied.

RESULTS

The Turkish AECT versions showed good convergent validity with a substantial correlation with anchor tools and known-group validity. Excellent internal consistency and reproducibility were observed. Equal or more than 10 of 16 points scored with the AECT-4wk and AECT-3mth identified patients with well-controlled disease. The disease activity, control and burden parameters were consistent with the disease control level defined depending on the cut-off point 10 of AECT. Three-point changes in AECT-4wk and -3 mt could detect MCID in disease control in all patients.

CONCLUSIONS

Turkish AECT versions are valid and reliable tools for assessing and monitoring disease control in patients with RAE. The use of the Turkish versions of the AECT in routine patient care, clinical trials and angioedema research is recommended.

Extremely Late Diagnosis of Hereditary Angioedema Type I in an Elderly Female

This case presents an instance of an extremely delayed diagnosis of hereditary angioedema (HAE) type I in an elderly female with no significant past medical history. The patient had a prolonged history of recurrent lip swelling and itchiness dating back to her teenage years, leading to multiple visits to the emergency room (ER). These recurrent episodes were characterized by random onset and accompanied by generalized pruritus and urticaria. During these ER visits, the patient would be inappropriately treated for presumed hypersensitivity reaction due to her confounding environmental allergies presenting with urticaria, complicating and significantly delaying her diagnosis. The patient was adopted, and the family history was unknown. There was no history of medication use suggestive of acquired angioedema. At the time of the visit, she had signs of chronic lip changes and atopy. After an extensive workup, it showed severely low levels of C1 esterase inhibitor and borderline low to normal C4 and C1q, consistent with the diagnosis of HAE type I. Initial treatment with an on-demand C1 esterase inhibitor reduced the recurrence of lip swelling and transitioned to long-term prophylaxis use. Overall, the treatment outcome was generally successful, with less recurrence of lip swelling and ER visits.

A Case of Trauma-Related Angioedema of the Airway in a Patient on an Angiotensin Receptor Blocker

BACKGROUND Angioedema is non-pitting edema that occurs in the deep layers of the skin and subcutaneous tissue due to vascular leakage of plasma resulting from 1 of 2 major pathophysiological processes: mast cell-mediated angioedema and bradykinin-mediated angioedema. While it is a well-recognized adverse reaction of angiotensin-converting enzyme inhibitors, the association of angioedema with angiotensin receptor blockers is relatively less studied. Direct local trauma, although rarely, has been suggested to induce angioedema under certain conditions. We present a unique case of direct, local, trauma-related angioedema in a patient on an angiotensin receptor blocker. CASE REPORT The patient, an 83-year-old woman on telmisartan for hypertension, hit her neck against the edge of a chair during a fall. Shortly thereafter, she developed progressive airway compromise due to airway angioedema, as noted on direct laryngoscopy. A contrast CT scan of the neck also noted edema of the periglottic and supraglottic regions. She required intravenous corticosteroid administration and intubation in the emergency room and was successfully extubated 3 days after admission. She had no prior history of angioedema or allergy. We hypothesize that increased levels of circulatory bradykinin in the setting of telmisartan, combined with a local release of bradykinin from trauma, was the main pathophysiologic cause of the angioedema. CONCLUSIONS This case report highlights the rare and often forgotten adverse reaction of angioedema with use of angiotensin receptor blockers and confirms the finding of local trauma as a possible trigger.

The bradykinin-forming cascade in anaphylaxis and ACE-inhibitor induced angioedema/airway obstruction

Anaphylaxis is a potentially life-threatening multi-system allergic reaction to a biological trigger resulting in the release of potent inflammatory mediators from mast cells and basophils and causing symptoms in at least two organ systems that generally include skin, lungs, heart, or gastrointestinal tract in any combination. One exception is profound hypotension as an isolated symptom. There are two types of triggers of anaphylaxis: immunologic and non-Immunologic. Immunologic anaphylaxis is initiated when a foreign antigen directly binds to IgE expressed on mast cells or basophils and induces the release of histamine and other inflammatory substances resulting in vasodilation, vascular leakage, decreased peripheral vascular resistance, and heart muscle depression. If left untreated, death by shock (profound hypotension) or asphyxiation (airway obstruction) can occur. The non-immunologic pathway, on the other hand, can be initiated in many ways. A foreign substance can directly bind to receptors of mast cells and basophils leading to degranulation. There can be immune complex activation of the classical complement cascade with the release of anaphylatoxins C3a and C5a with subsequent recruitment of mast cells and basophils. Finally, hyperosmolar contrast agents can cause blood cell lysis, enzyme release, and complement activation, resulting in anaphylactoid (anaphylactic-like) symptoms. In this report we emphasize the recruitment of the bradykinin-forming cascade in mast cell dependent anaphylactic reactions as a potential mediator of severe hypotension, or airway compromise (asthma, laryngeal edema). We also consider airway obstruction due to inhibition of angiotensin converting enzyme with a diminished rate of endogenous bradykinin metabolism, leading not only to laryngeal edema, but massive tongue swelling with aspiration of secretions.

The Occurrence of Atopy in Patients with Isolated Spontaneous Mast Cell (or Nonallergic) Angioedema

BACKGROUND

Isolated mast cell angioedema (MC-AE) can be divided into allergic and nonallergic (spontaneous) forms. The former is often associated with food, Hymenoptera venoms or drug allergies. This study aimed to evaluate the relationship between the occurrence of atopic diseases and the risk of angioedema.

METHODS

A retrospective study analyzed 304 patients with confirmed MC-AE and 1066 controls. All were analyzed for allergic asthma (AA), atopic dermatitis (AD) and allergic rhinitis (AR) based on ICD-10 codes. In addition, total IgE and peripheral eosinophilia were calculated.

RESULTS

The analyzed atopic diseases were more frequent in the group of patients diagnosed with MC-AE than in the controls: 78 (25.7%) vs. 173 (16.2%) for p < 0.01. Patients diagnosed with AD had a higher risk of MC-AE (hazard ratio (HR) = 1.48,) similar to those diagnosed with AR (HR = 1.51). However, in patients with two or three atopic comorbidities, the risk increased significantly to HR = 2.45 or HR = 4.1, respectively. There was a positive correlation between the serum total IgE concentration or eosinophilia and the risk of angioedema (p < 0.01).

CONCLUSION

Patients with MC-AE had a more frequent occurrence of atopic diseases associated with inhalant allergies. This risk increased in patients with IgE-mediated polymorphic disease.

Sirolimus potentiated angioedema: A case report and review of the literature

Introduction

In the realm of organ transplantation, particularly heart transplantation, angioedema presents a significant challenge. This clinical condition ranges from minor facial edema to life-threatening swelling of vital structures. Its multifactorial etiology involves various factors and mechanisms, including C1 esterase inhibitor deficiency, food allergen hypersensitivity, and adverse drug reactions, notably involving angiotensin-converting enzyme (ACE) inhibitors and mechanistic target of rapamycin inhibitors (mTOR-Is). We present a rare case of sirolimus potentiated angioedema in a patient with long-standing ACE inhibitor therapy.

Case

A 52-year-old male with a history of heart transplant developed severe upper and lower lip edema. The patient had been on Lisinopril without any adverse events. However, sirolimus was recently added to his drug regimen. Sirolimus potentiated angioedema was suspected.

Intervention

Intravenous methylprednisolone, famotidine, and diphenhydramine were initiated, and both lisinopril and sirolimus were discontinued. The patient showed improvement and was discharged with oral antihistamines.

Lessons

Transplant physicians should be aware of the life-threatening interaction between ACE inhibitors and mTOR-Is like sirolimus. Consideration should be given to switching from an ACE inhibitor to an angiotensin-receptor blocker when initiating patients on mTOR-Is.

Pharmacogenetic markers of development of angioneurotic edema as a secondary side effect to enalapril in patients with essential arterial hypertension

BACKGROUND

Angioneurotic edema is the most dangerous complication in angiotensin-converting enzyme inhibitors (ACEIs) therapy. Based on the current data, the clinical and genetic predictors of angioedema development are still understudied, which demonstrates the relevance of this study.

OBJECTIVE

To reveal the pharmacogenetic predictors of the angioedema as a secondary side effect to enalapril in patients with essential arterial hypertension.

METHODS

The study enrolled 111 subjects randomized into two groups: study group, patients with the angioedema as a secondary side effect to enalapril; and control group, patients without adverse drug reaction. All patients underwent pharmacogenetic testing.

RESULTS

An association between the development of the angioneurotic edema and the genotypes AA rs2306283 of gene SLCO1B1, TT rs4459610 of gene ACE, and CC rs1799722 of gene BDKRB2 in patients was revealed.

CONCLUSION

The findings justify further investigations of the revealed genetic predictors of angioedema with larger-size patient populations.

Hong Kong-Macau Severe Hives and Angioedema Referral Pathway

Background

Urticaria (defined as the presence of hives, angioedema, or both) can be caused by a variety of etiologies ranging from more common conditions such as chronic spontaneous urticaria (CSU) to rarer conditions such as hereditary angioedema (HAE). Specialist referral may be necessary in cases of severe urticaria or HAE, but access to specialist services remains limited in certain regions, such as the Greater Bay Area (GBA) of China. To address this, the Hong Kong-Macau Severe Hives and Angioedema Referral Pathway (SHARP) was initiated by the Hong Kong Institute of Allergy and Macau Society of Dermatology to promote multidisciplinary collaboration and regional exchange of expertise in the diagnosis and management of severe urticaria.

Methods

A nominated task force of dermatologists and immunologists who manage patients with severe urticaria formulated the consensus statements (CS) using the Delphi method. The consensus was defined a priori as an agreement of ≥80%.

Results

A total of 24 CS were formulated, including four statements on classifications and definitions, seven statements on diagnosis, and 13 statements on management and referral. The definitions for acute/chronic urticaria and severe CSU were stated. Unnecessary investigations and inappropriate medications were discouraged. The characteristics and recommended approach to suspected bradykinergic angioedema were specified. Stepwise treatment options using second-generation antihistamines, omalizumab, or cyclosporin for patients with CSU were addressed, and the importance of access to HAE-specific medications was emphasized. Furthermore, an integrated referral pathway for patients with severe hives and angioedema was constructed.

Conclusion

The SHARP provides guidance for the management and specialist referral of patients with severe hives and angioedema in Hong Kong and Macau.

Pharmacogenomic knowledge and awareness among diverse patients treated with angiotensin converting enzyme inhibitors

We developed novel electronic phenotyping algorithms for the BioMe biobank data, which accurately identified angiotensin converting enzyme inhibitor (ACEi)-induced angioedema cases and controls. A survey was mailed to all 1075 patients and 91 were returned. Over a third reported that prescribing physicians had not discussed with them the concepts of interindividual drug response variability or adverse event risk, and 73% of patients were previously unaware of pharmacogenomics; however, most patients were interested in having pharmacogenomic testing. Moreover, 67% of patients indicated that pharmacogenomic testing would positively influence their medication compliance. In addition to identifying an innovative approach to define biobank cohorts for pharmacogenomic studies, these results indicate that patients are interested in pharmacogenomic testing, which could translate to improved adherence.

Atypical Myasthenia gravis in an older person resulting in delayed diagnosis: a case report

Myasthenia gravis (MG) is a rare autoimmune neuromuscular disorder characterised by varying degrees of skeletal muscle weakness. Diagnosing MG represents a challenge for clinicians due to the diversity of disease manifestations. We present an unusual case of this disease in an older gentleman in which the patient reported swollen tongue and lips which was incorrectly diagnosed and treated as angioedema. Months later, he developed progressive dysphagia, dysarthria and weight loss. The diagnosis was further delayed by the identification of a hiatal hernia and Zenker's diverticulum after extensive investigation for dysphagia. A total of 15 months on prompted by persistent symptoms, the patient was found to have MG by positive antibody test and Electromyogram. Treatment was initiated which led to a rapid and significant relief of his symptoms.

Universal Access to On-Demand Treatment of Patients with Hereditary Angioedema, the Chilean Experience

Background: In Chile, patients with hereditary angioedema (HAE) type I and type II are protected under Ley Ricarte Soto (LRS), which guarantees access to on demand plasma-derived C1-INH (pdC1-INH) since 2018. We aimed to analyze the first 3 years of LRS. Methods: Review of the LRS database between 2018 and 2021. Results: During the study period, 154 patients were covered by LRS, with an estimated prevalence of HAE in Chile at 0.8:100,000 inhabitants. A delay in diagnosis of 22 years was noted, 50 patients received epinephrine during an attack before the diagnosis of HAE. Mean number of attacks per year was 8, with 50% of adults and 42% of children experiencing more than 1 attack per month. Conclusion: Disease awareness must improve to reduce the diagnostic delay of HAE. Long-term prophylactic medications should be included in LRS to treat patients with high attack rates and control the costs of frequent on-demand treatment with pdC1-INH.