Clinical features and complications of Loeys-Dietz syndrome: A systematic review

Cardiovascular pathology, inheritance and prognosis in a familial cohort of Loeys-Dietz type III

INTRODUCTION

Loeys-Dietz syndrome (LDS) is a heritable disease that is the result of dysregulation of the transforming growth factor beta (TGFβ) pathway. The pathogenic variants associated with the condition are linked to aortic aneurysms and dissections along with other cardiovascular and non-cardiovascular abnormalities. LDS type III is associated with pathogenic variants in the SMAD3 gene responsible for signally in the TGFβ pathway. Most of the current knowledge of LDS stems from studies of LDS I and II patient with limited data on large cohorts of LDS III patients. We sought to identify the prevalence and course of cardiovascular diseases in a large familial cohort of LDS III patients and also to compare these findings with a previously described cohort of similar size with the identical pathogenic variant.

METHODS

The cohort was identified by systematic genetic screening of a familial cohort identified through a single proband. Data was collected from retrospective chart review of patients identified to be affected by the syndrome.

RESULTS

Screening of 97 patients identified 19 patients (16 through genetic testing and 3 through phenotypic screening of untested direct descendants of genetically positive individuals). The prevalence of cardiovascular abnormalities was 84%. There was significant intrafamilial phenotypic variability within the cohort with the predominant cardiovascular abnormality being mitral valve disease followed by aortic disease. 92% of patients >18 years of age had osteoarthritis which is a further hallmark of LDS III.

CONCLUSION

LDS III sets itself apart from the more widely studied LDS types I and II cardiovascular phenotypes by presenting later in life and tending to be more strongly associated with mitral valve disease.

Delayed diagnosis of Loeys-Dietz syndrome revealed through atrial septal defect with pulmonary artery dilation

Loeys-Dietz syndrome (LDS) is an autosomal-dominant connective tissue disorder associated with mutations in the transforming growth factor β receptor. It is characterized by distinctive craniofacial changes, skeletal features, and cardiovascular complications. We present a case of a 24-year-old male with development delay and a one-year history of progressively worsening dyspnea on moderate exertion and orthopnea. Echocardiography revealed right atrial and right ventricle dilation, right ventricle hypertrophy, atrial septal defect, and aneurysmal dilation of the pulmonary artery trunk. This case underscores the importance of early detection and comprehensive imaging in patients suspected of having LDS, particularly considering the potential for atypical vascular manifestations.

Unraveling the genetic collagen connection: clinical and therapeutic insights on genetic connective tissue disorders

Hereditary connective tissue disorders include more than 200 conditions affecting different organs and tissues, compromising the biological role of the extracellular matrix through interference in the synthesis, development, or secretion of collagen and/or its associated proteins. The clinical phenotype includes multiple signs and symptoms, usually nonspecific but of interest to rheumatologists because of musculoskeletal involvement. The patient´s journey to diagnosis is long, and physicians should include these disorders in their differential diagnoses of diseases with systemic involvement. In this review, insights for the diagnosis and treatment of osteogenesis imperfecta, hypermobility spectrum disorder/Ehlers-Danlos syndrome, Marfan, Loeys-Dietz, and Stickler syndromes are presented.

Cardiac manifestations of human ACTA2 variants recapitulated in a zebrafish model

The ACTA2 gene encodes actin α2, a major smooth muscle protein in vascular smooth muscle cells. Missense variants in the ACTA2 gene can cause inherited thoracic aortic diseases with characteristic symptoms, such as dysfunction of smooth muscle cells in the lungs, brain vessels, intestines, pupils, bladder, or heart. We identified a heterozygous missense variant of Gly148Arg (G148R) in a patient with a thoracic aortic aneurysm, dissection, and left ventricular non-compaction. We used zebrafish as an in vivo model to investigate whether or not the variants might cause functional or histopathological abnormalities in the heart. Following the fertilization of one-cell stage embryos, we injected in vitro synthesized ACTA2 mRNA of wild-type, novel variant G148R, or the previously known pathogenic variant Arg179His (R179H). The embryos were maintained and raised for 72 h post-fertilization for a heart analysis. Shortening fractions of heart were significantly reduced in both pathogenic variants. A histopathological evaluation showed that the myocardial wall of ACTA2 pathogenic variants was thinner than that of the wild type, and the total cell number within the myocardium was markedly decreased in all zebrafish with pathogenic variants mRNAs. Proliferating cell numbers were also significantly decreased in the endothelial and myocardial regions of zebrafish with ACTA2 variants compared to the wild type. These results demonstrate the effects of ACTA2 G148R and R179H on the development of left ventricle non-compaction and cardiac morphological abnormalities. Our study highlights the previously unknown significance of the ACTA2 gene in several aspects of cardiovascular development.

Clinical and Therapeutic Intervention of Hypereosinophilia in the Era of Molecular Diagnosis

Hypereosinophilia (HE) presents with an elevated peripheral eosinophilic count of >1.5 × 109/L and is composed of a broad spectrum of secondary non-hematologic disorders and a minority of primary hematologic processes with heterogenous clinical presentations, ranging from mild symptoms to potentially lethal outcome secondary to end-organ damage. Following the introduction of advanced molecular diagnostics (genomic studies, RNA sequencing, and targeted gene mutation profile, etc.) in the last 1-2 decades, there have been deep insights into the etiology and molecular mechanisms involved in the development of HE. The classification of HE has been updated and refined following to the discovery of clinically novel markers and targets in the 2022 WHO classification and ICOG-EO 2021 Working Conference on Eosinophil Disorder and Syndromes. However, the diagnosis and management of HE is challenging given its heterogeneity and variable clinical outcome. It is critical to have a diagnostic algorithm for accurate subclassification of HE and hypereosinophilic syndrome (HES) (e.g., reactive, familial, idiopathic, myeloid/lymphoid neoplasm, organ restricted, or with unknown significance) and to follow established treatment guidelines for patients based on its clinical findings and risk stratification.

Echogenomics: Echocardiography in Heritable Aortopathies

PURPOSE OF REVIEW

The aim of this article is to review the current echocardiographic considerations in the diagnosis and monitoring of patients with inherited aortopathies.

RECENT FINDINGS

Aortic dilation is a key feature in heritable aortopathies, and dissection is a leading cause of morbidity and mortality. New genetic and histopathologic findings are helpful in better understanding these conditions. Non-invasive imaging modalities, including echocardiogram, computerized tomography, and magnetic resonance imaging, are essential in monitoring these patients, as well as providing new prognostic factors of arterial stiffness that may help with risk stratification in the future. Diagnosis of heritable aortopathies should be considered with identification of aortic root dilation, particularly in children and young adults, or when there is a family history of aortic disease. Recent adult consensus guidelines highlight the importance of underlying genotype and phenotypic features when considering prophylactic surgical intervention. There are currently no consensus pediatric guidelines.

Cellular, Molecular and Clinical Aspects of Aortic Aneurysm-Vascular Physiology and Pathophysiology

A disturbance of the structure of the aortic wall results in the formation of aortic aneurysm, which is characterized by a significant bulge on the vessel surface that may have consequences, such as distention and finally rupture. Abdominal aortic aneurysm (AAA) is a major pathological condition because it affects approximately 8% of elderly men and 1.5% of elderly women. The pathogenesis of AAA involves multiple interlocking mechanisms, including inflammation, immune cell activation, protein degradation and cellular malalignments. The expression of inflammatory factors, such as cytokines and chemokines, induce the infiltration of inflammatory cells into the wall of the aorta, including macrophages, natural killer cells (NK cells) and T and B lymphocytes. Protein degradation occurs with a high expression not only of matrix metalloproteinases (MMPs) but also of neutrophil gelatinase-associated lipocalin (NGAL), interferon gamma (IFN-γ) and chymases. The loss of extracellular matrix (ECM) due to cell apoptosis and phenotype switching reduces tissue density and may contribute to AAA. It is important to consider the key mechanisms of initiating and promoting AAA to achieve better preventative and therapeutic outcomes.

Hereditary Thoracic Aortic Diseases

Advances in both imaging techniques and genetics have led to the recognition of a wide variety of aortic anomalies that can be grouped under the term 'hereditary thoracic aortic diseases'. The present review aims to summarize this very heterogeneous population's clinical, genetic, and imaging characteristics and to discuss the implications of the diagnosis for clinical counselling (on sports activity or pregnancy), medical therapies and surgical management.

Comprehensive Cancer Genomic Profiling of Liver Metastasis Led to the Unexpected Identification of Colorectal Cancer

Comprehensive genomic profiling (CGP) of a metastatic liver tumor biopsy specimen suggested that the patient, who was initially diagnosed with cholangiocarcinoma, had colorectal cancer. The identification of both FBXW7 and APC mutations is deemed characteristic of colorectal cancer. Indeed, subsequent colonoscopy revealed sigmoid colon carcinoma that led to tumor resection followed by systemic chemotherapy. CGP is principally used to identify agents that might potentially benefit the patient. However, results must be interpreted carefully to ensure consistency with the initial diagnosis.

A Rare Case of Urinary Bladder Hamartoma Clinically Mimicking an Urothelial Carcinoma: A Case Report and Review of the Literature

Urinary bladder hamartoma is a rare benign proliferation with only 14 cases reported in the literature at present. Urinary bladder hamartoma is composed of a disorderly admixture of normal urinary bladder components, essentially represented by glands lined by transitional epithelium and a variable percentage of fibrous stroma, smooth muscle bundles, and adipose tissue. Urinary bladder hamartomas do not exhibit cytological or architectural abnormalities and show no necrosis or increase in mitotic activity. Clinical manifestations are usually represented by lower urinary tract symptoms, more or less frequently paired with gross hematuria. Several pediatric cases of urinary bladder hamartoma have been reported, sometimes with syndromic associations. Transurethral resection has been curative in all cases reported, with no evidence of recurrence. Here we report an additional rare urinary bladder hamartoma, clinically mimicking urothelial carcinoma, providing a review of the literature regarding this unusual entity.

Survival and repair durability in patients undergoing concomitant aortic valve reimplantation and mitral valve repair

Objective

The study objective was to determine repair durability and survival in patients with and without connective tissue disorders undergoing concomitant aortic valve reimplantation and mitral valve repair.

Methods

From 2002 to 2019, 68 patients underwent concomitant aortic valve reimplantation and mitral valve repair, including 27 patients with Marfan syndrome (39.7%). Follow-up echocardiograms were analyzed using nonlinear multiphase mixed-effects cumulative logistic regression. The regurgitation grade over time was estimated by averaging patient-specific profiles. Survival and freedom from reoperation were estimated by the Kaplan-Meier method.

Results

At 7 years, 11% of patients had aortic insufficiency greater than mild (severe in 2 patients). There was no difference in greater than mild aortic insufficiency between patients with or without Marfan syndrome (P = .37). Twenty percent of patients had progressed to mitral regurgitation greater than mild (severe in only 1 patient). The prevalence of recurrent mitral regurgitation was higher in those without Marfan syndrome, with greater than mild regurgitation increasing to 24% by 2 years and remaining constant thereafter (P = .04). Freedom from reoperation on the aortic valve or mitral valve was 83% at 10 years and did not differ between Marfan syndrome groups. There were no cases of perioperative mortality. Survival at 5 and 10 years was 94% and 87%, respectively, without a difference between those with and without Marfan syndrome.

Conclusions

Patients can undergo a total repair strategy using combined aortic valve reimplantation and mitral valve repair procedures with a low risk of mortality and complications, with favorable freedom from both residual valve regurgitation and reoperation.

Smooth Muscle Heterogeneity and Plasticity in Health and Aortic Aneurysmal Disease

Vascular smooth muscle cells (VSMCs) are the predominant cell type in the medial layer of the aorta, which plays a critical role in the maintenance of aortic wall integrity. VSMCs have been suggested to have contractile and synthetic phenotypes and undergo phenotypic switching to contribute to the deteriorating aortic wall structure. Recently, the unprecedented heterogeneity and diversity of VSMCs and their complex relationship to aortic aneurysms (AAs) have been revealed by high-resolution research methods, such as lineage tracing and single-cell RNA sequencing. The aortic wall consists of VSMCs from different embryonic origins that respond unevenly to genetic defects that directly or indirectly regulate VSMC contractile phenotype. This difference predisposes to hereditary AAs in the aortic root and ascending aorta. Several VSMC phenotypes with different functions, for example, secreting VSMCs, proliferative VSMCs, mesenchymal stem cell-like VSMCs, immune-related VSMCs, proinflammatory VSMCs, senescent VSMCs, and stressed VSMCs are identified in non-hereditary AAs. The transformation of VSMCs into different phenotypes is an adaptive response to deleterious stimuli but can also trigger pathological remodeling that exacerbates the pathogenesis and development of AAs. This review is intended to contribute to the understanding of VSMC diversity in health and aneurysmal diseases. Papers that give an update on VSMC phenotype diversity in health and aneurysmal disease are summarized and recent insights on the role of VSMCs in AAs are discussed.

Fatigue in patients with syndromic heritable thoracic aortic disease: a systematic review of the literature and a qualitative study of patients' experiences and perceptions

INTRODUCTION

The purpose of this study was to explore the literature on fatigue in patients with syndromic heritable thoracic aortic disease (sHTAD), including Marfan syndrome (MFS), Loeys-Dietz syndrome (LDS), vascular Ehlers Danlos syndrome (vEDS) and other sHTADs, critically appraise and synthesize the relevant literature. We also aimed to investigate how adults with sHTAD experience and perceive fatigue, and to discuss clinical implications and direction for further research.

METHODS

First, a systematic review was performed by searching the published literature in all relevant databases and other sources until 20th October 2022. Second, a qualitative focus group interview study was conducted of 36 adults with sHTADs (LDS n = 11, MFS n = 14, vEDS n = 11).

RESULTS

In the systematic review, 33 articles satisfied the eligibility criteria (3 reviews and 30 primary studies). Of the primary studies: 25 dealt with adults (MFS n = 17, MFS/EDS n = 1, EDS n = 2, LDS/vEDS n = 3, different sHTADs n = 2), 5 with children (MFS n = 4, different sHTADs n = 1). Twenty-two were cross-sectional quantitative studies, 4 prospective and 4 qualitative studies. The quality of the included studies was mostly good, but many had small sample sizes, low response rates and/or participants without verified diagnosis. Despite these limitations, studies indicated high prevalence of fatigue (ranging from 37 to 89%), and fatigue was associated with both health and psychosocial aspects. Few studies found that fatigue was associated with disease-related symptoms. In the qualitative focus groups most of the participants reported that they had experienced fatigue which influenced several aspects of life. Four themes related to fatigue were elucidated: (1) different diagnoses-different fatigue?, (2) the nature of fatigue, (3) searches for causes of fatigue, (4) dealing with fatigue in daily life. The four themes seemed mutually interrelated in terms of barriers, strategies and facilitators for dealing with fatigue. The participants experienced fatigue as a consistent dilemma between self-assertion and inadequacy. Fatigue seems to influence several aspects of daily life and may be one of the most debilitating symptoms of having a sHTAD.

CONCLUSION

Fatigue seems to negatively impact the lives of people with sHTADs and should be recognized as an important aspect in the lifelong follow-up of these patients. The life-threatening complications of sHTADs may result in emotional stress, including fatigue and the risk of developing a sedentary lifestyle. Research and clinical initiatives should consider rehabilitation interventions aiming at postponing the onset or reducing symptoms of fatigue.

Genetic Problems, Diagnosis, and Cardiovascular Manifestations of Loeys-Dietz Syndrome

Loeys-Dietz Syndrome (LDS) is an autosomal dominant connective tissue disorder with multisystem involvement of wide spectrum, found to be associated with transforming growth factor-β pathway. LDS is characterized by craniofacial, skeletal, cutaneous, vascular abnormalities along with aortic aneurysm and aortic dissection contributing to mortality and morbidity at a young age. Therefore, timely diagnosis and intervention in patients with LDS is vital. Several gene mutations have been described as contributing factors of LDS, causing widespread and aggressive vascular disease. Based on these gene mutations, 5 types of LDS have been described so far. Besides aortic aneurysm and dissection, some of the other cardiac manifestations of LDS involve cardiomyopathy, valvular abnormality, atrial fibrillation, patent ductus arteriosus, atrial septal defects, etc. Routine imaging of patients' vasculatures and aggressive medical and surgical management are key factors in managing patients with LDS.

Vaskulitis mimics

Idiopathische Vaskulitiden sind seltene entzündliche Systemerkrankungen, die nach der Chapel-Hill Konsensus-Nomenklatur nach der Größe der prädominant betroffenen Gebiete von Blutgefäßen (große, mittelgroße, kleine Gefäße und Gefäße variabler Größe) eingeteilt werden. Vaskulitis mimics sind Syndrome, die ein ähnliches klinisches Bild hervorrufen oder leicht mit einer idiopathischen Vaskulitis verwechselt werden und teils sogar ein Krankheitsbild, das klinisch und histologisch einer Vaskulitis gleicht, auslösen können. Die Zahl der Vaskulitis mimics ist groß, je nach betroffenem Gefäßgebiet kommen hereditäre Erkrankungen des Bindegewebes, genetisch bedingte Immundefekt- und Autoinflammationssyndrome, infektiöse Erkrankungen, seltene entzündliche Systemerkrankungen, Tumorerkrankungen, medikamenteninduzierte Syndrome und zahlreiche weitere infrage. In diesem Review wird eine Auswahl klassischer Imitatoren von Vaskulitiden, orientiert an der Größe der betroffenen Blutgefäße präsentiert und Konstellationen, die typische „Fallstricke“ in der klinischen Abklärung darstellen können, diskutiert.

Adjustment to disease and quality of life in people with vascular Ehlers-Danlos and Loeys-Dietz syndromes: A mixed-method study

Background

Vascular Ehlers-Danlos (vEDS) and Loeys-Dietz syndromes (LDS) are hereditary disorders of connective tissue having severe vascular complications (HDCTv) which lead to an increased risk of premature death. Little is known about the impact of the disease in patient's daily life.

Method

Sixteen HDCTv patients (vEDS = 9 and LDS = 7), 16 age and sex-matched hypermobile Ehlers-Danlos syndrome patients (hEDS) and 18 healthy subjects (HS), responded to self-questionnaires assessing psychosocial adjustment, quality of life (QoL), anxiety, depression, pain, fatigue and sleep problems. Patients with HDCTv were also interviewed in order to explore qualitatively their experience with the disease.

Results

Compared with HS, patients with HDCTv scored significantly higher on anxiety, depression, fatigue, sleep problems, and lower on QoL. Most HDCTv patients (93.8%) have optimal psychosocial adjustment. In addition, HDCTv patients scored higher on QoL and psychosocial adjustment, but lower in pain, fatigue, sleep problems, and depressive symptoms than hEDS patients. Four main themes were identified in qualitative analyses: living with HDCTv, knowledge/ignorance of the disease, health behaviors/self-care and coping strategies.

Conclusion

Our results suggest that despite the negative impact of HDCTv on the patients' daily lives, overall, they present an optimal disease adjustment which points to appropriate coping strategies. More research in psychosocial aspects of people with these rare diseases are needed to confirm these results and better understand their needs.

Genetics and pathophysiology of mitral valve prolapse

Mitral valve prolapse (MVP) is a common condition affecting 2-3% of the general population, and the most complex form of valve pathology, with a complication rate up to 10-15% per year in advanced stages. Complications include mitral regurgitation which can lead to heart failure and atrial fibrillation, but also life-threatening ventricular arrhythmia and cardiovascular death. Sudden death has been recently brought to the forefront of MVP disease, increasing the complexity of management and suggesting that MVP condition is not properly understood. MVP can occur as part of syndromic conditions such as Marfan syndrome, but the most common form is non-syndromic, isolated or familial. Although a specific X-linked form of MVP was initially identified, autosomal dominant inheritance appears to be the primary mode of transmission. MVP can be stratified into myxomatous degeneration (Barlow), fibroelastic deficiency, and Filamin A-related MVP. While FED is still considered a degenerative disease associated with aging, myxomatous MVP and FlnA-MVP are recognized as familial pathologies. Deciphering genetic defects associated to MVP is still a work in progress; although FLNA, DCHS1, and DZIP1 have been identified as causative genes in myxomatous forms of MVP thanks to familial approaches, they explain only a small proportion of MVP. In addition, genome-wide association studies have revealed the important role of common variants in the development of MVP, in agreement with the high prevalence of this condition in the population. Furthermore, a potential genetic link between MVP and ventricular arrhythmia or a specific type of cardiomyopathy is considered. Animal models that allow to advance in the genetic and pathophysiological knowledge of MVP, and in particular those that can be easily manipulated to express a genetic defect identified in humans are detailed. Corroborated by genetic data and animal models, the main pathophysiological pathways of MVP are briefly addressed. Finally, genetic counseling is considered in the context of MVP.

Education and employment status among adults with Loeys-Dietz syndrome and vascular Ehlers-Danlos syndrome in Norway, a questionnaire based study

OBJECTIVES

To describe education level and employment status among adults with Loeys-Dietz syndrome and vascular Ehlers-Danlos syndrome, and explore factors related to work participation.

MATERIALS AND METHODS

Cross-sectional postal survey in 2018. Individuals with molecularly verified diagnosis were recruited through a National Resource Centre for Rare Disorders. A study specific questionnaire included topics on disease burden and validated instruments regarding education level, employment, pain, fatigue, psychological distress, and satisfaction with life.

RESULTS

Fifty persons (56% women) aged 18-67 years, participated. Almost 60% reported education level ≤13 years. Two thirds (66%) received disability benefits, 21 (42%) had full-time disability pension. The median age at ending work was 41 years. Full-time employed and students were younger (p = 0.014), less fatigued (p = 0.035), had less sleep problems (p = 0.028) and higher satisfaction with life (p<0.001) than those who received disability pension. A third (32%) were currently or used to be in sedentary work, and 68% currently had or used to be in practical work requiring much standing and walking (23%), much walking and lifting (34%) or heavy manual work (11%).

CONCLUSIONS

There is a potential that more adults with these diagnoses can sustain employment for more years. Health and social service follow-up routines and future studies should include details on employment perspectives to reveal those at risk of poor employment and to identify modifiable factors for work participation.