Survey of actual conditions of erythema marginatum as a prodromal symptom in Japanese patients with hereditary angioedema

Hereditary angioedema with normal C1 esterase inhibitor: Current paradigms and clinical dilemmas

Background: A diagnosis of hereditary angioedema (HAE) with normal C1 esterase inhibitor (HAE-nl-C1-INH) can be challenging and pharmacologic management is not well defined. Objective: The objective was to discuss practical considerations in the clinical management of HAE-nl-C1-INH by using illustrative clinical vignettes to highlight and/or address select challenges. Methods: This was a narrative review. Results: Symptoms of HAE-nl-C1-INH overlap with HAE types I and II; the heterogeneity of presentation and symptom burden are diagnostic challenges. A patient history, with particular attention to whether urticaria or other symptoms of mast cell mediator release are present, is important because such symptoms would strongly suggest a mast cell-mediated pathway. A family history of angioedema is informative but a lack thereof does not rule out diagnosis. Expected laboratory findings would be normal for C4, C1-INH level and function, and Complement 1q; a genetic mutational analysis may be helpful, but current assays do not include all known mutations; most cases are categorized as unknown. To align with guideline-directed treatment approaches, the following stepwise approach is suggested for suspected HAE-nl-C1-INH: (1) thoroughly investigate the possibility of response to histaminergic and/or mast cell-targeting treatments; (2) if patients with normal C4, C1-INH level and/or function fail adequate trials with histamine/mast cell-directed therapy or have a mutation that suggests bradykinin pathway involvement, follow HAE type I and II treatment guidelines. Response to medications approved for HAE types I/II provides compelling support for a high clinical suspicion of HAE-nl-C1-INH. De-labeling an HAE-nl-C1-INH diagnosis may be appropriate if the initial diagnosis was made without adequate evaluation or if new information and/or testing indicates that the patient does not actually have HAE. Conclusion: Key unmet needs in HAE-nl-C1-INH include lack of confirmatory biomarker(s) for diagnosis and lack of prospective controlled clinical studies of pharmacologic products in this patient population.

Urticaria and mimickers of urticaria

Urticaria is a common skin condition encountered across various specialties in medicine, especially in dermatology and allergy/immunology practice. It has a heterogeneous presentation hence it is unsurprising that many skin conditions may be confused with urticaria. Urticaria may present as acute or chronic urticaria, the latter can be further categorised into chronic spontaneous and chronic inducible. In this article, we explore, explain, and summarise various skin lesions that are considered mimickers of urticaria, to promote understanding of each of the conditions highlighted, improve recognition, and reduce misdiagnosis.

National survey on clinical and genetic characteristics of patients with hereditary angioedema in Latvia

BACKGROUND

Hereditary angioedema (HAE) is a rare and life-threatening inborn error of immunity. HAE is mostly caused by pathogenic variations in the serine protease inhibitor gene 1 (SERPING1), leading to deficient or dysfunctional C1-inhibitor (C1-INH), overproduction of bradykinin, and development of recurrent subcutaneous and/or submucosal oedema. The prevalence of HAE is 1 in 50,000 - 100000 people worldwide. We aimed to describe the clinical features and genetic spectrum of hereditary angioedema with C1-INH deficiency (C1-INH-HAE) in Latvia.

METHODS

All patients from Latvia diagnosed with HAE (types I/II) from 2006 to March 2022 were included in the study. Laboratory tests and clinical data were analysed, and genetic tests with Sanger sequencing and whole genome sequencing were performed.

RESULTS

The study identified 10 C1-INH-HAE patients (nine females, one male) from eight families. The point prevalence of HAE in Latvia is 0.53 per 100 000 inhabitants. Of all patients, seven (70%) had HAE type I and three (30%) had HAE type II. The median age of patients was 54 years and the median age at onset of symptoms was 15 years. A significant delay (median 20.5 years) until diagnosis was observed, and 60% of patients had a positive family history of angioedema. All HAE patients have been hospitalised a median two times during their lifetime. Skin (100%), abdominal (80%), and airway (80%) oedema were the most frequent symptoms. Triggering factors (60%) and prodromal symptoms (90%) were referred. Attacks were severe in 50% of patients, moderate in 10%, and mild in 40%. Pathogenic variations of SERPING1 were identified in eight patients (six families), confirming the diagnosis molecularly. In two patients (two families), no pathogenic variations in the genes were found even after whole genome sequencing.

CONCLUSIONS

Current data shows a significant delay and clear underdiagnosis of HAE in Latvia. Higher awareness and better information and communication between doctors would improve the diagnosis and management of HAE; as would screening of family members, patients with recurrent angioedema unresponsive to antihistamines and glucocorticoids, and patients with recurrent episodes of severe, unexplained abdominal pain.

Hereditary Angioedema: Diagnostic Algorithm and Current Treatment Concepts

Hereditary angioedema (HAE) is an uncommon disorder with a global prevalence of approximately 1 in 10,000 to 1 in 50,000 population. This disease is grossly underrecognized in India because of lack of awareness and/or lack of diagnostic facilities. Clinical manifestations include swelling over face, eyes, lips, hands, feet, and genitals, abdominal pain, and life-threatening laryngeal edema. HAE should be suspected in all patients who present with angioedema without wheals and who do not respond to antihistamines and/or steroids. C1 levels, C1-INH levels, and C1-INH function should be checked in all patients suspected to have HAE. C1q levels should be assessed in patients with suspected autoimmune-mediated acquired angioedema. Management of HAE constitutes the treatment of acute attack and short-term and long-term prophylaxis. Because of lack of all first-line recommended medications, the management of HAE in India is a challenging task. Patients are managed using fresh frozen plasma (acute treatment), tranexamic acid, and attenuated androgens (prophylaxis). Even though attenuated androgens have been shown to be effective in the prevention of attacks of HAE, the side effect profile especially in children and in females is a serious concern. Hence, the treatment needs to be individualized considering the risk-benefit ratio of long-term prophylaxis. In this review, we provide an overview of diagnostic strategy for patients with HAE and the current treatment concepts with emphasis on currently available treatment options in resource-constrained settings.