Hereditary disorders of connective tissue: a guide to the emerging differential diagnosis

Integrative medicine for hypermobility spectrum disorders (HSD) and Ehlers-Danlos syndromes (EDS): a feasibility study

PURPOSE

Hypermobility spectrum disorders (HSD) and Ehlers-Danlos syndromes (EDS) are multisystem conditions marked by dysfunctional connective tissue. This feasibility study evaluated a 9-week integrative medicine program in this population.

METHODS

Using a single-arm study design, adults with HSD or EDS were given recommendations for an anti-inflammatory Mediterranean diet and self-management with additional behavioral and psychosocial support. Preliminary data on feasibility based on recruitment and retention, adherence to the diet, mobile app tracking, changes to perceived well-being via health outcomes, and satisfaction with care were obtained.

RESULTS

Thirteen participants were enrolled within a 4-month timeframe. Eight participants completed the study. Three participants met dietary tracking requirement in at least 4 of 8 intervention weeks and met the macronutrient requirements in at least half of the weeks tracked. No decreases in VAS pain scores after 5 and 9 weeks were noted; however, 62.5% (n = 5) of participants had decreased pain at 9 weeks, compared to baseline. There were significant improvements (p<.05) in six of twelve measurements of satisfaction with care at the end of the intervention.

CONCLUSION

This study provides a foundation for future research on patient experience and introduces a novel treatment paradigm focused on nutrition and self-management.

Trial Registration: National Institutes of Health clinicaltrials.gov; identifier: NCT04734041.

IMPLICATIONS FOR REHABILITATION

Lifestyle and dietary interventions are relatively safe and well tolerated in the hypermobility spectrum disorder (HSD) and Ehlers-Danlos disorder (EDS) population.Participants in our 9-week integrative medicine program actively engaged in self-management of their condition and showed promising adherence to dietary and tracking requirements.Effective treatment of the intricacies and dynamics of these highly variable and clinically heterogeneous disorders may require a network of healthcare providers, integrative healthcare, as well as behavioral and psychosocial support.Dietary tracking through mobile apps might help promote self-efficacy and adherence to dietary changes.Symptom tracking might be an effective way for patients to track changes to their health and could provide valuable information for health professionals engaged in managing the disorders.

Human genetics and molecular genomics of Chiari malformation type 1

Chiari malformation type 1 (CM1) is the most common structural brain disorder involving the craniocervical junction, characterized by caudal displacement of the cerebellar tonsils below the foramen magnum into the spinal canal. Despite the heterogeneity of CM1, its poorly understood patho-etiology has led to a 'one-size-fits-all' surgical approach, with predictably high rates of morbidity and treatment failure. In this review we present multiplex CM1 families, associated Mendelian syndromes, and candidate genes from recent whole exome sequencing (WES) and other genetic studies that suggest a significant genetic contribution from inherited and de novo germline variants impacting transcription regulation, craniovertebral osteogenesis, and embryonic developmental signaling. We suggest that more extensive WES may identify clinically relevant, genetically defined CM1 subtypes distinguished by unique neuroradiographic and neurophysiological endophenotypes.

Pathophysiology of spontaneous coronary artery dissection: hematoma, not thrombus

Spontaneous coronary artery dissection (SCAD) accounts for 1.7%-4% of all acute coronary syndrome presentations, particularly among young women with an emerging awareness of its importance. The demarcation of acute SCAD from coronary atherothrombosis and the proper therapeutic approach still represents a major clinical challenge. Certain arteriopathies and triggers are related to SCAD, with high variability in their prevalence, and often, the cause remains unknown. The objective of this review is to provide contemporary knowledge of the pathophysiology of SCAD and possible therapeutic solutions.

Patient experience of chronic illness care and complementary integrative health use: a cross-sectional study of patients with hypermobility spectrum disorders (HSD) and Ehlers-Danlos syndromes (EDS)

PURPOSE

Hypermobility spectrum disorders (HSD) and Ehlers-Danlos syndromes (EDS) are frequently underdiagnosed, contributing to patient dissatisfaction in the healthcare system. This study evaluated the health service utilization, care, and subjective experiences of living with chronic illness among adults with HSD and EDS in the United States and Canada.

METHODS

This was an anonymous, web-based, cross-sectional healthcare survey. The survey obtained basic demographic information, the Patient Assessment of Chronic Illness Care (PACIC+), as well as responses to questions on the use of healthcare and integrative medicine.

RESULTS

A total of 353 surveys were received. The most common complementary therapies used were physical therapy (82%), massage (68%), yoga (58%), chiropractic (48%), and meditation (43%). Mean (SD) summary PACIC and PACIC 5 As scores were 2.16 (0.77) and 2.25 (0.83), respectively. Across all PACIC domains, mean scores of individuals whose typical doctor visit was 30 min or at least an hour were significantly higher than those of individuals who indicated typical visits of 15 min (all p < 0.0001 by one-way ANOVA). There was widespread agreement on the importance of patient-provider relationship and trust, physicians' understanding of the individual's complete medical history, and prioritization of physical and emotional safety (>95% agree or strongly agree to each).

CONCLUSION

Individuals with HSD or EDS report low satisfaction with chronic illness care and commonly seek out complementary and self-administered therapies, likely in an attempt to manage symptoms. Respondents reported a desire for greater time and attention from physicians. Results from this study could educate the healthcare community to improve support mechanisms for HSD and EDS populations.IMPLICATIONS FOR REHABILITATIONPatients with hypermobility spectrum disorders (HSD) or Ehlers-Danlos syndromes (EDS) express a desire for patient-centered care and peer support from other individuals with HSD or EDS.Individuals with HSD or EDS have typically seen multiple doctors for their condition and their satisfaction with chronic care, as measured by the Patient Assessment of Chronic Illness Care (PACIC+), is low.The use of various complementary and integrative health treatments, as well as specialized diets, is common in this population, and might be beneficial for symptom management.Healthcare delivery for HSD and EDS may require a multidisciplinary healthcare team, as complementary and self-care modalities are typically used in addition to physical therapy, pain medication, and other conventional care.

FKBP14 kyphoscoliotic Ehlers-Danlos syndrome misdiagnosed as Larsen syndrome: a case report

Hereditary connective tissue disorders have overlapping phenotypes, particularly in regard to musculoskeletal features. This contributes to the challenge of phenotype-based clinical diagnoses. However, some hereditary connective tissue disorders have distinct cardiovascular manifestations that require early intervention and specific management. Molecular testing has increased the ability to categorize and diagnose distinct hereditary connective tissue disorders. A 42-yr-old female with a clinical diagnosis of Larsen syndrome from birth presented for genetic testing based on her recent diagnosis of premenopausal breast cancer. She had a past medical history of multiple carotid dissections. As she never had confirmatory molecular genetic testing for Larsen syndrome, whole-exome sequencing was utilized to assess both hereditary cancer predisposition syndromes and connective tissue disorders. A homozygous pathogenic variant in the FKBP14 gene was identified associated with FKBP14 kyphoscoliotic Ehlers-Danlos syndrome. We recommend that patients with a clinical diagnosis of Larsen syndrome undergo broad-based molecular sequencing for multiple hereditary connective tissue disorders. Molecular diagnosis is particularly crucial for all individuals who have a history of significant vascular events in the setting of a clinical diagnosis only. Early diagnosis of a hereditary connective tissue disorder with vascular features allows for screening and subsequent prevention of cardiovascular events.

Bone fragility in Hereditary Connective Tissue Disorders: a Systematic Review and Meta-analysis

OBJECTIVE

To investigate bone fragility in patients with hereditary connective tissue disorders (HCTD), including Ehlers-Danlos syndrome (EDS), Marfan's syndrome (MFS) and Loeys-Dietz syndrome (LDS).

METHODS

From inception to June 2022, potentially eligible studies were identified in the Medline and EMBASE databases using search strategy that included terms for "HCTD", "Fracture" and "Osteoporosis". Eligible studies must consist of a group of patients with HCTD and report prevalence/incidence of fracture/osteoporosis in their participants, with or without comparison with healthy individuals. Point estimates with standard errors were obtained from each study and combined using the generic inverse variance method.

RESULTS

Among the 4,206 articles identified, 19 studies were included. The pooled prevalence of fracture in EDS, MFS and LDS were 44% (95%CI, 25 - 65%, I² 88%), 17% (95%CI, 11 - 26%, I² 68%), 69% (95%CI, 47 - 85%, I² 83%), respectively. The pooled prevalence of osteoporosis in EDS was 17% (95%CI, 8 - 34%, I² 96%). EDS was associated with fracture [pooled odds ratio 4.90 (95%CI, 1.49 - 16.08, I² 86%)], but not osteoporosis [pooled odds ratio 1.34 (95%CI, 0.28 - 6.36, I² 87%). One study reported a 5% (95%CI, 3 - 8%) prevalence of osteoporosis in MFS, which was associated with fracture [incidence rate ratio 1.35 (95%CI, 1.18 - 1.55)] and osteoporosis [subhazard ratio 3.97 (95%CI, 2.53 - 6.25)].

CONCLUSION

EDS was associated with fracture, which could be independent of osteoporosis status. MFS had a milder degree of increased risk of fracture and osteoporosis. Despite no data from cohort studies, there was a significantly higher rate of fracture in LDS.

Anesthetic challenges in the management of Larsen syndrome: A rare congenital anomaly

Larsen syndrome is a rare inherited disease associated with dislocations of multiple joints, typical syndromic facies, and multiple spine abnormalities. They often required multiple corrective orthopedic surgeries to regain their functional ability, thus needing repeated anesthesia. Apart from skeletal deformities, they have predicted difficult airway and need extreme care during intubation and positing of the patient. Abnormal posturing due to spinal deformity and poor pulmonary reserve due to kyphoscoliosis creates an extremely challenging situation for the anesthetist to manage the case during the perioperative period. Here we are describing the perioperative anesthetic management of a patient with Larsen syndrome.

Arterial dissections: Common features and new perspectives

Arterial dissections, which involve an abrupt tear in the wall of a major artery resulting in the intramural accumulation of blood, are a family of catastrophic disorders causing major, potentially fatal sequelae. Involving diverse vascular beds, including the aorta or coronary, cervical, pulmonary, and visceral arteries, each type of dissection is devastating in its own way. Traditionally they have been studied in isolation, rather than collectively, owing largely to the distinct clinical consequences of dissections in different anatomical locations - such as stroke, myocardial infarction, and renal failure. Here, we review the shared and unique features of these arteriopathies to provide a better understanding of this family of disorders. Arterial dissections occur commonly in the young to middle-aged, and often in conjunction with hypertension and/or migraine; the latter suggesting they are part of a generalized vasculopathy. Genetic studies as well as cellular and molecular investigations of arterial dissections reveal striking similarities between dissection types, particularly their pathophysiology, which includes the presence or absence of an intimal tear and vasa vasorum dysfunction as a cause of intramural hemorrhage. Pathway perturbations common to all types of dissections include disruption of TGF-β signaling, the extracellular matrix, the cytoskeleton or metabolism, as evidenced by the finding of mutations in critical genes regulating these processes, including LRP1, collagen genes, fibrillin and TGF-β receptors, or their coupled pathways. Perturbances in these connected signaling pathways contribute to phenotype switching in endothelial and vascular smooth muscle cells of the affected artery, in which their physiological quiescent state is lost and replaced by a proliferative activated phenotype. Of interest, dissections in various anatomical locations are associated with distinct sex and age predilections, suggesting involvement of gene and environment interactions in disease pathogenesis. Importantly, these cellular mechanisms are potentially therapeutically targetable. Consideration of arterial dissections as a collective pathology allows insight from the better characterized dissection types, such as that involving the thoracic aorta, to be leveraged to inform the less common forms of dissections, including the potential to apply known therapeutic interventions already clinically available for the former.

Assessment of the beliefs, needs, and expectations for genetic counseling of patients with hypermobile Ehlers-Danlos syndrome

Ehlers-Danlos syndrome, hypermobility type (hEDS) is a heritable connective tissue disorder that currently does not have a known molecular etiology. Previous studies have explored the complex symptomology, clinical diagnosis, and psychological aspects of hEDS. Genetics providers currently aid in the diagnosis and management guidance of patients with hEDS, but there is limited data describing the needs and expectations of individuals with hEDS from a clinical genetics appointment. Our study sought to explore these items through the use of an online survey to assess participants' beliefs, needs and expectations (BNE) for genetic counseling as well as questions about demographics, hEDS symptoms, and current medical care. A total of 460 respondents with hEDS completed the survey. Most participants felt joint pain/weakness (n = 392; 88%) was one of the most disruptive symptoms of hEDS and 63% (n = 289) reported having psychiatric conditions. BNE scores were highest in two domains: expectations to have psychosocial concerns addressed during a genetic counseling appointment (mean score = 4.4/5; SD = 0.56) and desire for positive feelings after a genetic counseling session (mean score = 4.3/5; SD = 0.59). Participants who previously had genetic counseling felt less unsure about their diagnosis (p = 0.02) and had lower need for information about hEDS (p < 0.001). Majority of participants did not feel that their doctors were knowledgeable about hEDS (n = 269; 58%) and strongly supported a multidisciplinary approach to their care (n = 445; 97%). This research provides a framework for genetics providers and other healthcare professionals to assess the needs and expectations of patients with hEDS and consider re-structuring their appointment formats to service this population.

Next-generation sequencing and analysis of consecutive patients referred for connective tissue disorders

Heritable connective tissue disorders (HCTDs) consist of a wide array of genetic disorders such as Ehlers-Danlos syndrome, Marfan syndrome, and osteogenesis imperfecta. The diagnosis relies on clinical presentation and family history to guide genetic testing with next-generation sequencing (NGS) for identification of gene variants in HCTDs. NGS was performed on a cohort of 100 consecutive, unrelated patients referred for a connective tissue disorder at Fulgent Genetics, an accredited commercial laboratory. One hundred seventeen gene variants were found in 76 patients with 10 recognized pathogenic or likely pathogenic variants seen in nine patients. The remaining variants were grouped as unknown clinical significance with 36 meeting three out of four pathogenicity criteria, or potentially pathogenic, as defined in our study in 33 patients. They were judged as potentially pathogenic for clinical care and management with disease surveillance based on the specific gene and phenotypic presentation. Gene variants in collagen-related proteins were the most frequent with ZNF469 and ADAMTSL2 variants most often identified. Joint hypermobility was the most frequent clinical finding. Variants were found in 76% of patients who had distinct clinical features of a HCTD. The data were stratified to provide insight into frequency and types of variants, their classification, and clinical manifestations.

The use of telemedicine in cardiogenetics clinical practice during the COVID-19 pandemic

Background

The COVID‐19 pandemic has necessitated the rapid and widespread adoption of novel mechanisms of service delivery, including the use of telemedicine. The aim of this study was to examine the impact of COVID‐19 on cardiogenetics practices.

Methods

We retrospectively analyzed the clinical characteristics of patients who were seen for cardiogenetics visits pre‐pandemic (1 April–23 December 2019) and during the pandemic (1 April–23 December 2020) at Columbia University Irving Medical Center.

Results

Six percent (n = 6) of visits in 2019 were remote telemedicine encounters, whereas 80% (n = 106) of visits in 2020 were telemedicine encounters. In 2019, only 18% (n = 19) of the patients seen for genetic counseling were family members of probands; this percentage increased to 34% in 2020 (n = 45; p = .01). In 2020, the geographic reach of genetic counseling also extended far beyond New York State, reaching a total of 11 states as well as one patient in Puerto Rico. Genetic testing results were similar in 2019 and 2020.

Conclusion

Despite the health‐care delivery barriers created by the COVID‐19 pandemic, the use of telemedicine allowed us to expand the reach of cardiovascular genetic counseling and testing.

Autoantibodies in Common Connective Tissue Diseases: A Primer for Laboratory Professionals

Background

Autoimmune connective tissue disorders are a significant health concern throughout the world with an estimated prevalence of 3% to 5%. They are associated with a variety of autoantibodies that play roles in their diagnosis, risk stratification, prognostication, and/or management. While some autoantibodies have been well-characterized for use in clinical laboratories, many more are in the research stage. Rapid transition from research to clinical practice, lack of clinical guidelines, and harmonization across a rapidly growing number of commercially available tests create numerous challenges to clinicians and laboratories.

Content

This article briefly discusses common connective tissue disorders and their association with well-known autoantibodies, describes current methods used in clinical laboratories, and outlines their advantages and limitations in the context of these diseases.

Summary

Understanding the role of specific autoantibodies and various methodologies for autoantibody testing are important for laboratory professionals who may be introducing/repatriating new tests, updating existing tests, or advising clinicians/patients about testing options/results. Collaboration between laboratory professional staff and clinicians, around the advantages and limitations of each methodology, is also important in their appropriate clinical utilization.

Expanding the phenotypic spectrum of Mendelian connective tissue disorders to include prominent kidney phenotypes

Heritable connective tissue disorders are a group of diseases, each rare, characterized by various combinations of skin, joint, musculoskeletal, organ, and vascular involvement. Although kidney abnormalities have been reported in some connective tissue disorders, they are rarely a presenting feature. Here we present three patients with prominent kidney phenotypes who were found by whole exome sequencing to have variants in established connective tissue genes associated with Loeys-Dietz syndrome and congenital contractural arachnodactyly. These cases highlight the importance of considering connective tissue disease in children presenting with structural kidney disease and also serves to expand the phenotype of Loeys-Dietz syndrome and possibly congenital contractural arachnodactyly to include cystic kidney disease and cystic kidney dysplasia, respectively.

Diversity in heritable disorders of connective tissue at a single center

BACKGROUND

Heritable disorders of connective tissue (HDCT) is a heterogeneous group of conditions caused by defects in genes responsible for extracellular matrix elements. Although next-generation sequencing (NGS) technology can be used to analyze many genes at a time, precisely diagnosing HDCT is still challenging because of the overlapping phenotypes and genotypes.

METHODS

A 67-gene NGS targeted panel or whole-exome sequencing was employed for the diagnosis of HDCT over 4 years. Phenotypes and genotypes of patients were analyzed retrospectively.

RESULTS

Mutations in 16 genes were discovered in 34 patients with the suspicion of Ehlers-Danlos syndrome (n = 7), Marfan syndrome (n = 2), osteogenesis imperfecta (n = 3), skeletal dysplasia (n = 18), and others (n = 4). Eighteen patients were found to have mutations in collagen genes, three had SERPINF1 mutations, two had TRPV4 mutations, two had FBN1 mutations, two had COMP mutations, and mutations in seven other genes were found in one patient each. The eight patients with COL1A1 mutations had a wide variation in phenotype. Patients with COL3A1 and COL5A1 mutations presented with classic EDS, those with SERPINF1 mutations presented with typical OI type VI, those with TRPV4 mutations presented with severe spinal deformity, and those with COL2A1 mutations presented with syndromic or nonsyndromic bone dysplasia or only short stature.

CONCLUSION

A wide diversity in HDCT was observed. Therefore, knowledge about the phenotype-genotype correlation in HDCT is still crucial in the diagnosis of this group of diseases, and an improvement in the screening tool will be needed.

Hybrid repair versus conventional open repair for aortic arch dissection

BACKGROUND

A dissection of the aorta is a separation or tear of the intima from the media. This tear allows blood to flow not only through the original aortic flow channel (known as the true lumen), but also through a second channel between the intima and media (known as the false lumen). Aortic dissection is a life-threatening condition which can be rapidly fatal. There is debate on the optimal surgical approach for aortic arch dissection. People with ascending aortic dissection have poor rates of survival. Currently open surgical repair is regarded as the standard treatment for aortic arch dissection. We intend to review the role of hybrid and open repair in aortic arch dissection.

OBJECTIVES

To assess the effectiveness and safety of a hybrid technique of treatment over conventional open repair in the management of aortic arch dissection.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 8 February 2021. We also undertook reference checking for additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and clinical controlled trials (CCTs), which compared the effects of hybrid repair techniques versus open surgical repair of aortic arch dissection. Outcomes of interest were dissection-related mortality and all-cause mortality, neurological deficit, cardiac injury, respiratory compromise, renal ischaemia, false lumen thrombosis (defined by partial or complete thrombosis) and mesenteric ischaemia.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all records identified by the literature searches to identify those that met our inclusion criteria. We planned to undertake data collection and analysis in accordance with recommendations described in the Cochrane Handbook for Systematic Reviews of Interventions. We planned to assess the certainty of the evidence using GRADE.

MAIN RESULTS

We identified one ongoing study and two unpublished studies that met the inclusion criteria for the review. Due to a lack of study data, we could not compare the outcomes of hybrid repair to conventional open repair for aortic arch dissection.

AUTHORS' CONCLUSIONS

This review revealed one ongoing RCT and two unpublished RCTs evaluating hybrid versus conventional open repair for aortic arch surgery. Observational data suggest that hybrid repair for aortic arch dissection could potentially be favourable, but conclusions can not be drawn from these studies, which are highly selective, and are based on the clinical status of the patient, the presence of comorbidities and the skills of the operators. However, a conclusion about its definitive benefit over conventional open surgical repair cannot be made from this review without published RCTs or CCTs. Future RCTs or CCTs need to have adequate sample sizes and follow-up, and assess clinically-relevant outcomes, in order to determine the optimal treatment for people with aortic arch dissection. It must be noted that this may not be feasible, due to the reasons mentioned.

Perioperative outcomes following pelvic floor reconstruction in women with hereditary disorders of connective tissue: a retrospective cohort study

INTRODUCTION AND HYPOTHESIS

Women with hereditary disorders of connective tissue (HDCT) are at increased risk of pelvic organ prolapse (POP) and stress urinary incontinence (SUI). We hypothesized that patients would have increased incidence and severity of perioperative complications up to 6 weeks after surgeries for POP/SUI. Secondary objectives were to compare pre- and post-operative pelvic floor symptoms and anatomical support as well as pelvic floor disorder recurrence.

METHODS

In this multi-center retrospective cohort study, we identified patients with HDCTs by patient history and ICD-9 codes over an 11-year period. Controls without HDCTs were matched 2:1 to the primary POP or SUI procedure and surgeon. Demographic characteristics, perioperative pelvic floor information and complications were collected. A sample size of 65 HDCT patients and 130 controls was calculated to detect a 20% difference in complications with 80% power and alpha of 0.05.

RESULTS

We identified 59 HDCT patients and 118 controls. Of the women with HDCTs, 49% had Ehlers-Danlos, 22% joint hypermobility syndrome, 15% Marfan syndrome, and 14% had others. Compared with controls, HDCT patients had more total perioperative complications (46% vs 22%, p = 0.002); an age-adjusted relative risk of complications was 1.4 (CI 0.7-2.6). HDCT patients had more Clavien-Dindo grades I and II complications (p = 0.02, 0.03) and more hospital readmissions (14% vs 3%, p = 0.01) than controls. There was no difference in the incidence of specific complications nor was there a difference in recurrence of POP (10%) or SUI (11%) between groups.

CONCLUSIONS

Patients with HDCTs had more Clavien-Dindo grade I and II complications following pelvic floor reconstructive surgery and more readmissions.

Hypermobile Ehlers-Danlos syndrome (hEDS) phenotype in fragile X premutation carriers: case series

BACKGROUND

While an association between full mutation CGG-repeat expansions of the Fragile X Mental Retardation 1 (FMR1) gene and connective tissue problems are clearly described, problems in fragile X premutation carriers (fXPCs) CGG-repeat range (55-200 repeats) of the FMR1 gene may be overlooked.

OBJECTIVE

To report five FMR1 fXPCs cases with the hypermobile Ehlers-Danlos syndrome (hEDS) phenotype.

METHODS

We collected medical histories and FMR1 molecular measures from five cases who presented with joint hypermobility and loose connective tissue and met inclusion criteria for hEDS.

RESULTS

Five cases were female and ranged between 16 and 49 years. The range of CGG-repeat allele sizes ranged from 66 to 150 repeats. All had symptoms of hEDS since early childhood. Commonalities in molecular pathogenesis and coexisting conditions between the fXPCs and hEDS are also presented. The premutation can lead to a reduction of fragile X mental retardation protein, which is crucial in maintaining functions of the extracellular matrix-related proteins, particularly matrix metallopeptidase 9 and elastin. Moreover, elevated FMR1 messenger RNA causes sequestration of proteins, which results in RNA toxicity.

CONCLUSION

Both hEDS phenotype and premutation involvement may co-occur because of related commonalities in pathogenesis.

Loss-of-Function Variants in EFEMP1 Cause a Recognizable Connective Tissue Disorder Characterized by Cutis Laxa and Multiple Herniations

Hereditary disorders of connective tissue (HDCT) compromise a heterogeneous group of diseases caused by pathogenic variants in genes encoding different components of the extracellular matrix and characterized by pleiotropic manifestations, mainly affecting the cutaneous, cardiovascular, and musculoskeletal systems. We report the case of a 9-year-old boy with a discernible connective tissue disorder characterized by cutis laxa (CL) and multiple herniations and caused by biallelic loss-of-function variants in EFEMP1. Hence, we identified EFEMP1 as a novel disease-causing gene in the CL spectrum, differentiating it from other HDCT.

Impaired angiogenesis and extracellular matrix metabolism in autosomal-dominant hyper-IgE syndrome

There are more than 7000 described rare diseases, most lacking specific treatment. Autosomal-dominant hyper-IgE syndrome (AD-HIES, also known as Job's syndrome) is caused by mutations in STAT3. These patients present with immunodeficiency accompanied by severe nonimmunological features, including skeletal, connective tissue, and vascular abnormalities, poor postinfection lung healing, and subsequent pulmonary failure. No specific therapies are available for these abnormalities. Here, we investigated underlying mechanisms in order to identify therapeutic targets. Histological analysis of skin wounds demonstrated delayed granulation tissue formation and vascularization during skin-wound healing in AD-HIES patients. Global gene expression analysis in AD-HIES patient skin fibroblasts identified deficiencies in a STAT3-controlled transcriptional network regulating extracellular matrix (ECM) remodeling and angiogenesis, with hypoxia-inducible factor 1α (HIF-1α) being a major contributor. Consistent with this, histological analysis of skin wounds and coronary arteries from AD-HIES patients showed decreased HIF-1α expression and revealed abnormal organization of the ECM and altered formation of the coronary vasa vasorum. Disease modeling using cell culture and mouse models of angiogenesis and wound healing confirmed these predicted deficiencies and demonstrated therapeutic benefit of HIF-1α-stabilizing drugs. The study provides mechanistic insights into AD-HIES pathophysiology and suggests potential treatment options for this rare disease.

Transcaval aortic valve implantation in a patient with Larsen syndrome: technical and anesthetic challenges

Transcatheter aortic valve implantation has emerged as a therapeutic option for patients with symptomatic severe aortic stenosis who are inoperable, or at very high risk of open-heart surgery. Recently, we encountered a patient with aortic stenosis and Larsen syndrome, who had short stature, obesity, kyphoscoliosis, multiple musculoskeletal deformities, and severe restrictive lung disease. An open-heart surgery in such a patient involves substantial peri-operative risk. A successful transcaval aortic valve implantation was done under general anesthesia.

Dural ectasia in Marfan syndrome and other hereditary connective tissue disorders: a 10-year follow-up study

BACKGROUND CONTEXT

Dural ectasia is widening of the dural sac often seen in patients with Marfan syndrome and other hereditary connective tissue disorders. Dural ectasia can cause specific symptoms and is associated with surgical complications. The knowledge on how and at which age dural ectasia develops is incomplete. There is no established gold standard for diagnosing dural ectasia, making it difficult to compare results from different studies.

PURPOSE

Our primary aim was to explore whether the radiological findings of dural ectasia changed after 10 years in an adult cohort with suspected Marfan syndrome. Our secondary aim was to re-evaluate the radiological criteria of dural ectasia.

STUDY DESIGN

Prospective cohort study.

PATIENT SAMPLE

Sixty-two persons from a cross-sectional study of 105 persons with suspected Marfan syndrome were included in a 10-year follow-up of dural ectasia. Forty-six were diagnosed with Marfan syndrome, 7 with Loeys-Dietz syndrome, and 5 with other hereditary connective tissue disorders. For comparison 64 matched hospital controls were evaluated.

OUTCOME MEASURES

Previously used radiological criteria for dural ectasia based on quantitative measurements of the lumbosacral spine.

METHODS

MRI of the lumbosacral spine was performed if not contraindicated, and if so then CT was performed. Differences in the study group between baseline and follow-up were assessed with paired Student t test, Wilcoxon rank signed test, and McNemar test. Receiver operating characteristic curves were constructed to assess the ability of radiological measurement to differentiate between the study and control group.

RESULTS

Fifty-two of 58 patients with hereditary connective tissue disorders and 11 controls had dural ectasia at follow-up. Forty-five Marfan patients had dural ectasia at follow-up vs. 41 at baseline. Five Loeys-Dietz patients had dural ectasia at follow-up vs. four at baseline. Twenty-four Marfan and 2 Loeys-Dietz patients had anterior sacral meningocele at follow-up, compared with 21 and 1, respectively, at baseline. Three Marfan patients developed herniation of a nerve root sleeve during follow-up. This was not seen in other individuals. The dural sac ended significantly lower at follow-up, and the dural sac ratio at level L5 was significantly increased from baseline in the Marfan patients.

CONCLUSIONS

In Marfan and Loeys-Dietz syndrome, dural ectasia may present or worsen during adulthood. The cut-off value of dural sac ratio at level S1 is suggested elevated to 0.64. The results from the present study may help as guidance for appropriate follow-up of patients with dural ectasia.

Pathogenic variants in PLOD3 result in a Stickler syndrome-like connective tissue disorder with vascular complications

Background

Pathogenic PLOD3 variants cause a connective tissue disorder (CTD) that has been described rarely. We further characterise this CTD and propose a clinical diagnostic label to improve recognition and diagnosis of PLOD3-related disease.

Methods

Reported PLOD3 phenotypes were compared with known CTDs utilising data from three further individuals from a consanguineous family with a homozygous PLOD3 c.809C>T; p.(Pro270Leu) variant. PLOD3 mRNA expression in the developing embryo was analysed for tissue-specific localisation. Mouse microarray expression data were assessed for phylogenetic gene expression similarities across CTDs with overlapping clinical features.

Results

Key clinical features included ocular abnormalities with risk for retinal detachment, sensorineural hearing loss, reduced palmar creases, finger contractures, prominent knees, scoliosis, low bone mineral density, recognisable craniofacial dysmorphisms, developmental delay and risk for vascular dissection. Collated clinical features showed most overlap with Stickler syndrome with variable features of Ehlers-Danlos syndrome (EDS) and epidermolysis bullosa (EB). Human lysyl hydroxylase 3/PLOD3 expression was localised to the developing cochlea, eyes, skin, forelimbs, heart and cartilage, mirroring the clinical phenotype of this disorder.

Conclusion

These data are consistent with pathogenic variants in PLOD3 resulting in a clinically distinct Stickler-like syndrome with vascular complications and variable features of EDS and EB. Early identification of PLOD3 variants would improve monitoring for comorbidities and may avoid serious adverse ocular and vascular outcomes.

Next-generation sequencing of 32 genes associated with hereditary aortopathies and related disorders of connective tissue in a cohort of 199 patients

PURPOSE

Heritable factors play an important etiologic role in connective tissue disorders (CTD) with vascular involvement, and a genetic diagnosis is getting increasingly important for gene-tailored, personalized patient management.

METHODS

We analyzed 32 disease-associated genes by using targeted next-generation sequencing and exome sequencing in a clinically relevant cohort of 199 individuals. We classified and refined sequence variants according to their likelihood for pathogenicity.

RESULTS

We identified 1 pathogenic variant (PV; in FBN1 or SMAD3) in 15 patients (7.5%) and ≥1 likely pathogenic variant (LPV; in COL3A1, FBN1, FBN2, LOX, MYH11, SMAD3, TGFBR1, or TGFBR2) in 19 individuals (9.6%), together resulting in 17.1% diagnostic yield. Thirteen PV/LPV were novel. Of PV/LPV-negative patients 47 (23.6%) showed ≥1 variant of uncertain significance (VUS). Twenty-five patients had concomitant variants. In-depth evaluation of reported/calculated variant classes resulted in reclassification of 19.8% of variants.

CONCLUSION

Variant classification and refinement are essential for shaping mutational spectra of disease genes, thereby improving clinical sensitivity. Obligate stringent multigene analysis is a powerful tool for identifying genetic causes of clinically related CTDs. Nonetheless, the relatively high rate of PV/LPV/VUS-negative patients underscores the existence of yet unknown disease loci and/or oligogenic/polygenic inheritance.

Clinical diagnosis of Larsen syndrome, Stickler syndrome and Loeys-Dietz syndrome in a 19-year old male: a case report

Background

Larsen syndrome is a hereditary disorder characterized by osteochondrodysplasia, congenital large-joint dislocations, and craniofacial abnormalities. The autosomal dominant type is caused by mutations in the gene that encodes the connective tissue protein, filamin B (FLNB). Loeys-Dietz syndrome (LDS) is an autosomal dominant connective tissue disorder characterized by arterial aneurysms, dissections and tortuosity, and skeletal, including craniofacial, manifestations. Mutations in five genes involved in the transforming growth factor beta (TGF-β) signaling pathway cause five types of LDS. Stickler syndrome is a genetically heterogeneous arthro-ophthalmopathy caused by defects in collagen, exhibiting a wide specter of manifestations in connective tissue. A rare case is reported that was diagnosed with all these three hereditary connective tissue disorders.

Case presentation

A 19 year-old, Norwegian male with a clinical diagnosis of Larsen syndrome and with healthy, non-consanguineous parents attended a reference center for rare connective tissue disorders. Findings at birth were hypotonia, joint hypermobility, hyperextended knees, adductovarus of the feet, cervical kyphosis, craniofacial abnormalities, and an umbilical hernia. From toddlerhood, he required a hearing aid due to combined conductive and sensorineural hearing loss. Eye examination revealed hyperopia, astigmatism, and exotropia. At 10 years of age, he underwent emergency surgery for rupture of an ascending aortic aneurysm. At 19 years of age, a diagnostic re-evaluation was prompted by the findings of more distal aortic dilation, tortuosity of precerebral arteries, and skeletal findings. High throughput sequencing of 34 genes for hereditary connective tissue disorders did not identify any mutation in FLNB, but did identify a de novo missense mutation in TGFBR2 and a nonsense mutation in COL2A1 that was also present in his unaffected father. The diagnosis was revised to LDS Type 2. The patient also fulfills the proposed criteria for Stickler syndrome with bifid uvula, hearing loss, and a known mutation in COL2A1.

Conclusion

LDS should be considered in patients with a clinical diagnosis of Larsen syndrome, in particular in the presence of arterial aneurysms or tortuosity. Due to genetic heterogeneity and extensive overlap of clinical manifestations, genetic high throughput sequencing analysis is particularly useful for the differential diagnosis of hereditary connective tissue disorders.

Cyst Masquerading as Inadvertent Bleb After a Scleral-Fixated Intraocular Lens in Marfan Syndrome: A Case Report

INTRODUCTION

To present a case of an epithelial inclusion cyst masquerading as an inadvertent bleb in a patient with Marfan syndrome.

CASE REPORT

A woman with Marfan syndrome presented with a subluxed crystalline lens in her right eye, which progressively subluxed over the following 2 years. A lensectomy was performed with placement of an anterior chamber intraocular lens (IOL); however, the patient experienced blurred vision and photopsias and preferred IOL explantation. The IOL was removed and a scleral-fixated posterior chamber IOL was placed. Vision improved with an uncomplicated postoperative course. Five months later, the patient experienced sudden onset redness and sharp pain in this eye. A 3-mm cystic lesion with tan material was found over a prior scleral incision site. Intraocular pressure was normal and no aqueous leaked from the lesion. Owing to concerns of an infected inadvertent bleb, treatment with topical and oral antibiotics was started, but the lesion did not change in appearance and the patient experienced persistent pain. The lesion was surgically excised and histopathology revealed a conjunctival epithelial inclusion cyst with intralesional keratin. A month later, another conjunctival inclusion cyst developed and was excised per patient preference.

CONCLUSION

Marfan syndrome is characterized by defects in the FBN1 gene and may theoretically lead to an abnormal sclera, increasing the risk of bleb formation after scleral incision. Distinguishing between a filtering bleb and an epithelial inclusion cyst is critical in patient care. Although retained keratin from a cyst may mimic a bleb with purulence, intraocular pressure, aqueous leakage, and response to topical antibiotics may help distinguish between the two.

Tracheocutaneous Sinus following Tracheocutaneous Fistula Repair: Management Strategies in a Pediatric Patient

Objective

To present a rare case of a pediatric tracheocutaneous sinus years after repair of a tracheocutaneous fistula and to review management strategies.

Background

A tracheocutaneous fistula is a common sequela of pediatric tracheostomy and can occur in as many as one in three pediatric patients. There is debate in the literature regarding optimal surgical management.

Case Presentation

An 8-year-old girl presented to the emergency department with swelling and erythema over the anterior neck. Clinical exam and diagnostic imaging revealed an underlying tracheocutaneous sinus.

Discussion

Complications following pediatric tracheostomy are common and range in complexity from stomal granulation to tracheocutaneous fistula. There is some debate regarding the optimal surgical management of children with tracheocutaneous fistula following tracheostomy. This report discusses the management of a pediatric child with an unusual tracheocutaneous sinus and reviews the various surgical techniques which have been described for definitive repair.

Bi-allelic Alterations in AEBP1 Lead to Defective Collagen Assembly and Connective Tissue Structure Resulting in a Variant of Ehlers-Danlos Syndrome

AEBP1 encodes the aortic carboxypeptidase-like protein (ACLP) that associates with collagens in the extracellular matrix (ECM) and has several roles in development, tissue repair, and fibrosis. ACLP is expressed in bone, the vasculature, and dermal tissues and is involved in fibroblast proliferation and mesenchymal stem cell differentiation into collagen-producing cells. Aebp1-/- mice have abnormal, delayed wound repair correlating with defects in fibroblast proliferation. In this study, we describe four individuals from three unrelated families that presented with a unique constellation of clinical findings including joint laxity, redundant and hyperextensible skin, poor wound healing with abnormal scarring, osteoporosis, and other features reminiscent of Ehlers-Danlos syndrome (EDS). Analysis of skin biopsies revealed decreased dermal collagen with abnormal collagen fibrils that were ragged in appearance. Exome sequencing revealed compound heterozygous variants in AEBP1 (c.1470delC [p.Asn490_Met495delins(40)] and c.1743C>A [p.Cys581∗]) in the first individual, a homozygous variant (c.1320_1326del [p.Arg440Serfs∗3]) in the second individual, and a homozygous splice site variant (c.1630+1G>A) in two siblings from the third family. We show that ACLP enhances collagen polymerization and binds to several fibrillar collagens via its discoidin domain. These studies support the conclusion that bi-allelic pathogenic variants in AEBP1 are the cause of this autosomal-recessive EDS subtype.

Congenital unruptured aneurysm of sinus of Valsalva, quadricuspid aortic valve, and ascending aortic aneurysm associated with genetic leukoencephalopathy in an infant: A new syndrome?

We report a 15-month-old female with unruptured noncoronary sinus of Valsalva anreurysm (SOVA) associated with quadricuspid aortic valve, ascending aortic aneurysm (AAA), moderate aortic insufficiency, mild mitral insufficiency, genetic leukoencepaholpathy, developmental delay and mild mixed aminoaciduria. She was referred for evaluation of a cardiac murmur. Initial echocardiographic examination showed the aneurysm as a round cyst in the right atrium which changed in size during systole and diastole. As to the best of our knowledge, this is the first report of association of SOVA, quadricuspid aortic valve, AAA and genetic leukoencephalopathy in an infant. These associations may suggest a new syndrome. We describe the echocardiographic and computed tomographic angiography findings. We also review 641 cases in the literature and the current six classification systems for SOVA.

Aortic dilation, genetic testing, and associated diagnoses

PURPOSE

The aims of this study were to determine the genetic diagnoses most frequently associated with aortic dilation in a large population and to describe the results of genetic testing in the same.

METHODS

A retrospective review of records from patients with known aortic dilation identified through an echocardiogram database was performed. During the study period, different chromosomal microarray platforms and molecular diagnostic techniques were used.

RESULTS

A total of 715 patients (mean age, 9.7 years; 67% male) met study inclusion criteria. The overall frequency of underlying presumptive or confirmed genetic diagnoses was 17% (125/715). Molecular evaluation for possible underlying aortopathy-related disorders was performed in 9% of patients (66/715). Next-generation sequencing panels were performed in 16 patients, and pathogenic abnormalities were detected in 4 (25%). Microarrays were conducted in 10% of patients (72/715), with a total of 23 pathogenic copy-number variants identified in 19 patients (26%). Marfan syndrome was the most frequently recognized genetic disorder associated with aortic dilation, but other cytogenetic abnormalities and associated diagnoses also were identified.

CONCLUSION

The differential diagnosis in patients with aortic dilation is broad and includes many conditions outside the common connective tissue disorder spectrum. A genetics evaluation should be considered to assist in the diagnostic evaluation.Genet Med 18 4, 356-363.

Comparative analysis of a novel disease phenotype network based on clinical manifestations

Systems approaches to analyzing disease phenotype networks in combination with protein functional interaction networks have great potential in illuminating disease pathophysiological mechanisms. While many genetic networks are readily available, disease phenotype networks remain largely incomplete. In this study, we built a large-scale Disease Manifestation Network (DMN) from 50,543 highly accurate disease-manifestation semantic relationships in the United Medical Language System (UMLS). Our new phenotype network contains 2305 nodes and 373,527 weighted edges to represent the disease phenotypic similarities. We first compared DMN with the networks representing genetic relationships among diseases, and demonstrated that the phenotype clustering in DMN reflects common disease genetics. Then we compared DMN with a widely-used disease phenotype network in previous gene discovery studies, called mimMiner, which was extracted from the textual descriptions in Online Mendelian Inheritance in Man (OMIM). We demonstrated that DMN contains different knowledge from the existing phenotype data source. Finally, a case study on Marfan syndrome further proved that DMN contains useful information and can provide leads to discover unknown disease causes. Integrating DMN in systems approaches with mimMiner and other data offers the opportunities to predict novel disease genetics. We made DMN publicly available at nlp/case.edu/public/data/DMN.

Cardiomyopathy in young adults with classic mitral valve prolapse

BACKGROUND

In some inherited connective tissue diseases with involvement of the cardiovascular system, for example, Marfan syndrome, early impairment of left ventricular function, which have been described as Marfan-related cardiomyopathy has been reported. Our aim was to evaluate the left ventricular function in young adults with mitral valve prolapse without significant mitral regurgitation using two-dimensional strain imaging and to determine the possible role of the transforming growth factor-β pathway in its deterioration.

METHODS

We studied 78 young adults with mitral valve prolapse without mitral regurgitation in comparison with 80 sex-matched and age-matched healthy individuals. Longitudinal strain and strain rates were defined using spackle tracking. Concentrations of transforming growth factor-β₁ and β₂ in serum were determined by enzyme-linked immunosorbent assays.

RESULTS

In 29 patients, classic relapse was identified with a leaflet thickness of ≥ 5 mm; 49 patients had a non-classic mitral valve prolapse. Despite the similar global systolic function, a significant reduction in global strain was found in the classic group (-15.5 ± 2.9%) compared with the non-classic group (-18.7 ± 3.8; p = 0.0002) and the control group (-19.6 ± 3.4%; p < 0.0001). In young adults with non-classic prolapse, a reduction in longitudinal deformation was detected only in septal segments. Transforming growth factor-β₁ and β₂ serum levels were elevated in patients with classic prolapse as compared with the control group and the non-classic mitral valve prolapse group.

CONCLUSIONS

These changes in the deformations may be the first signs of deterioration of the left ventricular function and the existence of primary cardiomyopathy in young adults with mitral valve prolapse, which may be caused by increased transforming growth factor-β signalling.