Comprehensive management of hereditary hemorrhagic telangiectasia

Understanding hereditary hemorrhagic telangiectasia: From genetic anomalies to systemic manifestations, quality of life, and epistaxis management-Exploring the otolaryngologist's integral role

Hereditary hemorrhagic telangiectasia (HHT), also known as Osler-Rendu-Weber syndrome, is a rare autosomal dominant disorder characterized by vascular malformations. This comprehensive review aimed to provide an overview and summarize various aspects of HHT, including the genetic abnormalities, complications associated with visceral arteriovenous malformations (AVMs), prognosis of HHT, quality of life (QOL), and treatment of epistaxis. In addition, this review highlights the challenges in diagnosing HHT and emphasizes the critical role of otolaryngologists in the early detection of HHT. Otolaryngologists can refer patients with refractory epistaxis for AVM screening to expedite intervention. Mutation of the genes involved in the transforming growth factor-β signaling pathway leads to the incidence of HHT, resulting in the formation of abnormal blood vessel formation. These vascular malformations commonly manifest as telangiectasia on the skin and mucous membranes; however, epistaxis remains the hallmark symptom of HHT. The impact of HHT goes beyond the visible symptoms and often includes the formation of life-threatening visceral AVMs in the lungs, liver, and brain. The prognosis of patients with HHT is closely related to the development of these complications, necessitating timely diagnosis and intervention. Refractory epistaxis diminishes the QOL of patients with HHT. The management of epistaxis ranges from conservative measures to advanced interventions such as prevention, conservative treatments, ablation, surgical procedures, and the administration of anti-angiogenic agents. However, effective management requires a multidisciplinary approach. The diagnosis of HHT remains challenging due to its variable presentation and lack of awareness among physicians. This review highlights the importance of reducing the duration between symptom onset and diagnosis. Otolaryngologists who are experienced in the management of refractory epistaxis can aid in identifying potential cases of HHT. They can facilitate the initiation of screening for visceral AVMs via prompt recognition of the signs and symptoms of HHT, contributing to improved patient outcomes. Early detection and intervention through screening can extend the life expectancy of patients with HHT to levels comparable with that of the general population. In conclusion, this review provides insight into various aspects of HHT and emphasizes the importance of timely diagnosis and intervention in the mitigation of the potentially life-threatening complications associated with this disorder. Otolaryngologists play a critical role in this process, serving as gatekeepers to the identification of cases of HHT and implementation of appropriate screening and management pathways, thereby improving the life expectancy and QOL of patients.

Treatments of Epistaxis in Hereditary Hemorrhagic Telangiectasia: Systematic Review and Network Meta-Analysis

PURPOSE OF REVIEW

To analyze and compare the effects of epistaxis treatments for Hereditary Hemorrhagic Telangiectasia (HHT) patients.

RECENT FINDINGS

Of total of 21 randomized controlled trials (RCT), the data from 15 RCTs (697 patients, 7 treatments: timolol, propranolol, bevacizumab, doxycycline, tacrolimus, estriol/estradiol, and tranexamic acid) were pooled for the meta-analyses while the other 6 studies (treatments: electrosurgical plasma coagulation, KTP laser, postoperative packing, tamoxifen, sclerosing agent, and estriol) were reviewed qualitatively. When compared to placebo, propranolol offered the most improved epistaxis severity score, mean difference (MD), -1.68, 95% confidence interval (95%CI) [-2.80, -0.56] followed by timolol, MD -0.40, 95%CI [-0.79, -0.02]. Tranexamic acid significantly reduced the epistaxis frequency, MD -1.93, 95%CI [-3.58, -0.28]. Other treatments had indifferent effects to placebo. Qualitative analysis highlighted the benefits of tamoxifen and estriol. The adverse events of tranexamic acid, tacrolimus, propranolol, and estradiol were significantly reported. Propranolol, timolol, tranexamic acid, tamoxifen, and estriol were effective treatments which offered benefits to HHT patients in epistaxis management. Adverse events of tranexamic acid, tacrolimus, propranolol, and estradiol should be concerned.

Epistaxis limits the performed activities of daily living in proportion to its severity: a cross-sectional survey among patients with hereditary haemorrhagic telangiectasia

Background: We examined the severity of epistaxis in patients with hereditary haemorrhagic telangiectasia (HHT) and its relationship with the performed activities of daily living. Methodology: This cross-sectional survey included 36 patients with HHT in Japan. An anonymous questionnaire survey was conducted regarding the severity of epistaxis, the measures adopted to prevent epistaxis, and the limitations in the performed activities of daily living. The latter was assessed using a visual analogue scale (VAS). The correlation between epistaxis severity and the VAS score was analysed using Spearman’s rank correlation coefficient. Results: Of the 36 participants surveyed, 94.4% had >1 episode of epistaxis/week. The mean epistaxis severity score (ESS) was 4.3 (range, 0.9–8.4). Limitations in daily life, going out (within a day), meeting with others, eating with others, and going on overnight trips were positively correlated with the ESS. To prevent nosebleeds, 44.4% and 41.7% of the participants used medications and avoided drying their nasal cavities, respectively. Conclusions: Epistaxis impacted the daily life of patients with HHT in proportion to its severity. Nonetheless, less than half of the patients used medications or took precautions. Hence, further educational activities should be considered for medical professionals and patients.

Non-Coding RNAs and Hereditary Hemorrhagic Telangiectasia

Non-coding RNAs (ncRNAs) are functional ribonucleic acid (RNA) species that include microRNAs (miRs), a class of short non-coding RNAs (∼21–25 nucleotides), and long non-coding RNAs (lncRNAs) consisting of more than 200 nucleotides. They regulate gene expression post-transcriptionally and are involved in a wide range of pathophysiological processes. Hereditary hemorrhagic telangiectasia (HHT) is a rare disorder inherited in an autosomal dominant fashion characterized by vascular dysplasia. Patients can develop life-threatening vascular malformations and experience severe hemorrhaging. Effective pharmacological therapies are limited. The study of ncRNAs in HHT is an emerging field with great promise. This review will explore the current literature on the involvement of ncRNAs in HHT as diagnostic and pathogenic factors.

Integration of clinical parameters, genotype and epistaxis severity score to guide treatment for hereditary hemorrhagic telangiectasia associated bleeding

BACKGROUND

Hereditary Hemorrhagic Telangiectasia (HHT) is a rare inherited disorder characterized by development of mucocutaneous telangiectases and visceral organ arteriovenous malformations, which can lead to recurrent, spontaneous bleeding and development of iron deficiency anemia. The primary objective of this study was to ascertain the relationship between epistaxis severity scores (ESS), laboratory values, genotype, and phenotype in HHT. Our secondary objective was to assess efficacy of systemic antifibrinolytic therapy in reducing ESS in HHT.

METHODOLOGY

We conducted a retrospective review of patients seen at the UNC HHT Center from January 1, 2009 to February 28, 2015. ESS, demographics, and results of genetic testing were abstracted from the medical record. Response to antifibrinolytic therapy was evaluated by comparing pre-post ESS.

RESULTS

One hundred and forty nine patients were eligible with 116 having genetic testing and 33 without. Age, hemoglobin and ferritin levels were predictive of ESS. Of the 116 patients that underwent genetic testing: 63 had an ACVRL1 mutation, 40 had an ENG mutation, 2 had a SMAD4 mutation, and 11 patients had no pathologic HHT genetic variation detected. Compared to patients without a detectable HHT-associated genetic variation, patients with a HHT-associated genetic variation had higher ESS scores (p < 0.05). Neither ESS nor genotype was predictive of pulmonary or brain AVMs. Twenty-four HHT patients with ESS > 4 were started on antifibrinolytic therapy (tranexamic acid or aminocaproic acid) and had a post-treatment ESS recorded. All patients had a decrease in ESS of > 0.71 (minimal meaningful difference), but patients taking antifibrinolytics displayed larger decreases. No patients on antifibrinolytics experienced a VTE with median follow up of 13 months.

CONCLUSIONS

We demonstrate that the ESS correlates with age, hemoglobin and ferritin. Additionally, we demonstrate that HHT patients with genetic mutations have higher ESS scores. Our data demonstrate that antifibrinolytics are effective in decreasing epistaxis severity and safe with long-term use in HHT patients.

Osler-Weber-Rendu Syndrome in Relation to Dermatology

Osler-Weber-Rendu syndrome, also known as hereditary hemorrhagic telangiectasia, is a rare autosomal dominant disorder with an estimated worldwide prevalence of 1 case per 10,000 population. Its clinical manifestations are the result of arteriovenous malformations characterized by telangiectases that can affect the skin, mucous membranes, and solid organs and cause life-threatening conditions, such as liver disease, systemic emboli, and heart failure. Timely diagnosis is thus essential in order to prevent disease-related complications and offer genetic counseling to families. We review the clinical features of Osler-Weber-Rendu syndrome with a focus on mucocutaneous manifestations and their treatment.