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.

Loeys-Dietz syndrome with a novel in-frame SMAD3 deletion diagnosed as a result of postpartum aortic dissection: A case report.

OBJECTIVE: Loeys-Dietz syndrome (LDS) is a rare, autosomal dominant connective tissue disorder which can aggressively affect the aortic vasculature. Limited information is available regarding its impact on pregnancy and postpartum outcomes. CASE REPORT: A pregnant 38-year-old nulliparous woman with mild aortic regurgitation and family history of aortic aneurysms presented with an aortic root measuring 49 mm. Despite concerns of an underlying connective tissue disorder, a definitive diagnosis was not reached. She delivered under strict blood pressure control, developed intractable uterine atony, and underwent uterine artery embolization. On the second postpartum day, aortic dissection was incidentally diagnosed, and aortic root replacement surgery was performed. Genetic testing revealed a novel in-frame SMAD3 deletion [NM_005902.4: c.703_708del, (p.Ile235_Ser236del)], leading to a diagnosis of LDS type 3. CONCLUSION: This case highlights the high postpartum aortic dissection risk in women with LDS, emphasizing the importance of early diagnosis in pregnant women with few clinical symptoms.

Cardiovascular and obstetrical outcomes among delivering patients with Marfan or Loeys-Dietz syndrome: a retrospective analysis by hospital delivery setting.

BACKGROUND: Pregnancy is a high-risk time for patients with Marfan syndrome or Loeys-Dietz syndrome because of the risk for cardiovascular complications, including the risk for aortic dissection. Little is known about the differences in obstetrical and cardiac outcomes based on delivery hospital setting (academic or academic-affiliated vs community medical centers). OBJECTIVE: This study aimed to evaluate the obstetrical and cardiac outcomes of patients with Marfan syndrome or Loeys-Dietz syndrome based on delivery hospital setting. STUDY DESIGN: This was a secondary analysis of a retrospective, observational cohort study of singleton pregnancies among patients with a diagnosis of Marfan syndrome or Loeys-Dietz syndrome from 1990 to 2016. Patients were identified through the Marfan Foundation, the Loeys-Dietz Syndrome Foundation, or the Cardiovascular Connective Tissue Clinic at Johns Hopkins Hospital. Data were obtained via self-reported obstetrical history and verified by review of medical records. Nonparametric analyses were performed using Fisher's exact tests and Wilcoxon rank-sum tests. RESULTS: A total of 273 deliveries among patients with Marfan syndrome or Loeys-Dietz syndrome were included in this analysis (Table 1). More patients who had a known diagnosis before delivery of either Marfan syndrome or Loeys-Dietz syndrome delivered at an academic hospital as opposed to a community hospital (78.6% vs 59.9%; P=.001). Patients with Marfan syndrome or Loeys-Dietz syndrome who delivered at academic centers were more likely to have an operative vaginal delivery than those who delivered at community centers (23.7% vs 8.6%; P=.002). When the indications for cesarean delivery were assessed, connective tissue disease was the primary indication for the mode of delivery at community centers when compared with academic centers (55.6% vs 43.5%; P=.02). There were higher rates of cesarean delivery for arrest of labor and/or malpresentation at community hospitals than at academic centers (23.6% vs 5.3%; P=.01). There were no differences between groups in terms of the method of anesthesia used for delivery. Among those with a known diagnosis of Marfan syndrome or Loeys-Dietz syndrome before delivery, there were increased operative vaginal delivery rates at academic hospitals than at community hospitals (27.2% vs 15.1%; P=.03) (Table 2). More patients with an aortic root measuring ≥4 cm before or after pregnancy delivered at academic centers as opposed to community centers (33.0% vs 10.2%; P=.01), but there were no significant differences in the median size of the aortic root during pregnancy or during the postpartum assessment between delivery locations. Cardiovascular complications were rare; 8 patients who delivered at academic centers and 7 patients who delivered at community centers had an aortic dissection either in pregnancy or the postpartum period (P=.79). CONCLUSION: Patients with Marfan syndrome or Loeys-Dietz syndrome and more severe aortic phenotypes were more likely to deliver at academic hospitals. Those who delivered at academic hospitals had higher rates of operative vaginal delivery. Despite lower frequencies of aortic root diameter >4.0 cm, those who delivered at community hospitals had higher rates of cesarean delivery for the indication of Marfan syndrome or Loeys-Dietz syndrome. Optimal delivery management of these patients requires further prospective research.

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 (TGFß) 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 TGFß 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.

Arterial tortuosity in pediatric Loeys-Dietz syndrome patients.

Loeys-Dietz syndrome (LDS) is an autosomal connective tissue disorder commonly presenting with hypertelorism, bifid uvula, aortic aneurysms, and arterial tortuosity. The aim of the present study was to investigate differences in tortuosity index (TI) between genotypes of LDS, possible progression over time and its use as an adjunctive prognostic tool alongside aortic dimensions to aid timely surgical planning in pediatric patients. A retrospective observational study of pediatric LDS patients referred to our center (November 2012-February 2021) was conducted. Using magnetic resonance angiography (MRA) with 3D maximum intensity projection volume-rendered angiogram, arterial TI was measured. Twenty three patients had genetically confirmed LDS with at least one head and neck MRA and 19 had no less than one follow-up MRA available. All patients presented arterial tortuosity. Patients with TGFBR2 variants had greater values of TI compared to patients with TGFB2 variants (p = 0.041). For patients who did not undergo surgery (n = 18), z-scores at the level of the sinus of Valsalva showed a significant correlation with vertebral TI (rs = 0.547). There was one death during follow-up. This study demonstrates that patients with LDS and TGFBR2 variants have greater values of TI than patients with TGFB2 variants and that greatest values of TI are associated with increased aortic root z-scores. Furthermore, as TI decreases over time, less frequent neuroimaging follow-up can be considered. Nevertheless, additional studies are needed to better define more accurate risk stratification and long-term surveillance in these patients.

[Depressive and anxiety symptoms in hereditary connective tissue disorders : case description and systematic literature review]. / Depressieve en angstklachten bij erfelijke bindweefselaandoeningen: casus en systematisch literatuuroverzicht.

Hereditary connective tissue disorders are a broad group of congenital disorders that are characterized by a pathological weakness of the connective tissue as a result of an incorrect genesis, leading to multisystem complaints. We describe a 14-year-old patient with the hereditary connective tissue disorder Loeys-Dietz syndrome who was admitted to a child psychiatric crisis unit because of depressive and anxiety symptoms. A systematic literature search was carried out to analyze the prevalence of depressive and anxiety symptoms in individuals with hereditary connective tissue disorders Loeys-Dietz syndrome, Ehlers-Danlos syndrome and Marfan syndrome, to identify a possible association between these disorders and explanations for this. We conclude that there is an increased incidence of depression and anxiety symptoms in which pain, fatigue, social support and functioning, quality of life and functional limitations seem to play a role. There is a need for further research to determine exactly which factors contribute and how these can be targeted in prevention and treatment.

Ten-year follow-up study of a young woman with loeys-dietz syndrome: a case report.

We herein report the 10-year surgical course of a 27-year-old woman who underwent two surgeries after being diagnosed with Loeys-Dietz syndrome. As described in previous cases, this patient developed ectopic arterial enlargement. We followed her temporal changes over a 10-year period, including the changes in computed tomography, pathology, and surgery.

Retinal detachment in Loeys-Dietz syndrome.

Loeys-Dietz syndrome (LDS) is an autosomal-dominant connective-tissue disorder with vascular and musculoskeletal abnormalities similar to Marfan syndrome. However, unlike Marfan, retinal detachment (RD) is rarely reported, and screening protocols do not currently feature ophthalmic assessment or RD counseling. We report a 5-generation family affected by LDS, where RD occurred in six eyes of four individuals. The proband was an 84-year-old male recently diagnosed with type-V LDS (TGFß3 pathogenic variant c.899G>A, p.(Arg300Gln)). Further investigation was undertaken into the family's medical history. The proband experienced bilateral rhegmatogenous RD at age 60, requiring emergency surgical repair. Other notable ophthalmic features include unusual keratometry, abnormal biometry, and severe hayfever requiring long-term sodium cromoglycate treatment. The proband's sister, father, and uncle had also experienced RDs, all prior to LDS diagnosis. This series demonstrates that RD risk may be significant in LDS, and on occasion the presenting clinical feature. We suggest ophthalmic examination should be added to the initial assessment LDS patients, and patients informed of the early warning symptoms of retinal detachment. As in Marfan syndrome, LDS patients may exhibit cornea plana and abnormal corneal topography, producing atypical biometry. They may also present with allergic conjunctivitis, and awareness of these signs might facilitate earlier diagnosis.

Siblings with profound connective tissue disease: First report of biallelic TGFBR1-related Loeys-Dietz syndrome.

Heterozygous missense variants in TGFBR1, encoding one subunit of the transforming growth factor-beta receptor, are a well-established cause of Loeys-Dietz syndrome (LDS)-an autosomal dominant disorder with variable phenotypic expression. Patients with LDS have compromised connective tissues that can result in life-threatening arterial aneurysms, craniosynostosis, characteristic craniofacial and skeletal anomalies, skin translucency, and abnormal wound healing. We report a full sibship with a biallelic type of TGFBR1-related disease. Each born at 38 weeks had aortic root dilation, congenital diaphragmatic hernia (CDH), skin translucency, and profound joint laxity at birth. Both had progressive dilation of the aorta and recurrence of a diaphragmatic defect after plication early in infancy. Patient 1 died at 66 days of age and Patient 2 is alive at 4 years and 4 months of age with multiple morbidities including cystic lung disease complicated by recurrent pneumothoraces and ventilator dependence, craniosynostosis, cervical spine instability, progressive dilation of the aorta, worsening pectus excavatum, large lateral abdominal wall hernia, and diffuse aortic ectasia. Fibroblasts cultured from Patient 2 showed decreased TGF-ß responsiveness when compared to control fibroblasts, consistent with previous observations in cells from individuals with autosomal dominant LDS. Whole genome copy number evaluation and sequencing for both patients including their parents as reference revealed compound heterozygous variants of uncertain clinical significance in exon 2 of TGFBR1 (c.239G>A; p.Arg80Gln paternal and c.313C>G; p.His105Asp maternal) in both siblings in trans. Each parent with their respective variant has no apparent medical issues and specifically no LDS characteristics. Neither of these variants have been previously reported. Thousands of patients have been diagnosed with LDS-an established autosomal dominant disease. These siblings represent the first reports of biallelic TGFBR1-related LDS and expand the differential diagnosis of CDH.

Infant with Loeys-Dietz syndrome treated for febrile status epilepticus with COVID-19 infection: first reported case of febrile status epilepticus and focal seizures in a patient with Loeys-Dietz syndrome and review of literature.

Loeys-Dietz syndrome (LDS) is a rare, autosomal dominant multisystem disorder that is caused by mutations of transforming growth factor-ß receptors. Mutations in SMAD3 and TGFB3 have been recently reported.LDS is characterised by the triad of arterial tortuosity, hypertelorism and a bifid uvula or cleft palate among other cardiovascular, craniofacial and orthopaedic manifestations. Patients with LDS show clinical and genetic variability and there is a significant risk of reduced life expectancy due to widespread arterial involvement, aortic root dilation, aneurysms and an aggressive vascular course. Thus early genetic testing is warranted if clinical signs and history are suggestive of this potentially catastrophic disorder.LDS predisposes patients to aortic aneurysms and early death due to vascular malformations, but neurological emergencies, such as seizures and febrile status epilepticus, have not been reported.Febrile status epilepticus is the most common neurological emergency in childhood. Neurological manifestations of COVID-19 in the paediatric population are not as well described in medical literature.To the best of our knowledge, this is the first reported case of febrile status epilepticus with COVID-19 infection in an infant with LDS. Our patient had focal epileptiform activity emanating over the left posterior hemisphere, which evolved into an electrographic seizure on video EEG. Such patients have a heightened risk of epilepsy in the future, and this occurrence is consistent with a diagnosis of focal epilepsy. Neurological complications such as epilepsy and status epilepticus in a patient with LDS have never been reported before.A brief review of literature is also given here.

Intracranial Aneurysms in Loeys-Dietz Syndrome: A Multicenter Propensity-Matched Analysis.

BACKGROUND: Loeys-Dietz syndrome (LDS) is an autosomal dominant connective tissue disorder characterized by a classic triad of hypertelorism, bifid uvula and/or cleft palate, and generalized arterial tortuosity. There are limited data on the prevalence and rupture risk of intracranial aneurysms (IAs) in the setting of LDS, with no established guidelines. OBJECTIVE: To analyze the prevalence and rupture risk of IA in LDS. METHODS: Electronic medical records of patients with a confirmed diagnosis of LDS and available cerebrovascular imaging were reviewed. Patients were divided into 2 groups based on the presence of IA. Unmatched and propensity-matched analyses were used to identify potential risk factors for aneurysm formation. RESULTS: Records of 1111 patients were screened yielding a total of 60 patients with a diagnosis of LDS. Eighteen (30%) patients had IA, 4 (22.2%) of whom had multiple aneurysms for a total of 24 IAs. Twenty-three (95.8%) aneurysms were located in the anterior circulation; none of them were ruptured. On unmatched analysis, age ( P = .015), smoking history ( P = .034), hypertension ( P = .035), and number of extracranial aneurysms ( P < .001) were significantly higher in patients with IA. After matching for age, sex, race, stroke history, family history, and extracranial aneurysms, smoking history ( P = .009) remained significant. CONCLUSION: Patients with LDS have an increased risk of IAs, especially with a history of smoking. The prevalence rate of IAs in our series was 30%. Screening imaging should be considered at diagnosis, and patients should be encouraged to abstain from smoking. Further studies are needed to elucidate the risk of IA rupture and treatment considerations in this unique population.

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

INTRODUCTION: Loeys-Dietz syndrome (LDS) is a connective tissue disorder that arises from mutations altering the transforming growth factor ß signalling pathway. Due to the recent discovery of the underlying genetic mutations leading to LDS, the spectrum of characteristics and complications is not fully understood. METHODS: Our search included five databases (Pubmed, SCOPUS, Web of Science, EMBASE and google scholar) and included variations of "Loeys-Dietz Syndrome" as search terms, using all available data until February 2021. All study types were included. Three reviewers screened 1394 abstracts, of which 418 underwent full-text review and 392 were included in the final analysis. RESULTS: We identified 3896 reported cases of LDS with the most commonly reported features and complications being: aortic aneurysms and dissections, arterial tortuosity, high arched palate, abnormal uvula and hypertelorism. LDS Types 1 and 2 share many clinical features, LDS Type 2 appears to have a more aggressive aortic disease. LDS Type 3 demonstrated an increased prevalence of mitral valve prolapse and arthritis. LDS Type 4 and 5 demonstrated a lower prevalence of musculoskeletal and cardiovascular involvement. Amongst 222 women who underwent 522 pregnancies, 4% experienced an aortic dissection and the peripartum mortality rate was 1%. CONCLUSION: We observed that LDS is a multisystem connective tissue disorder that is associated with a high burden of complications, requiring a multidisciplinary approach. Ongoing attempts to better characterise these features will allow clinicians to appropriately screen and manage these complications.

Neonatal presentation of Loeys-Dietz syndrome: two case reports and review of the literature.

BACKGROUND: Loeys-Dietz syndrome (LDS) is a rare connective tissue disorder characterized by cardiovascular manifestations, especially aortic dilatations and arterial tortuosity, craniofacial and skeletal features, joint laxity or contractures, skin abnormalities, hypotonia and motor delay. Its diagnosis is established by the identification of a pathogenic variant in TGFBR1, TGFBR2, SMAD2, SMAD3, TGFB2 or TGFB3 genes. In newborns and toddlers, vascular complications such as aneurism rupture, aortic dissection, and intracerebral incidents, can occur already in the weeks of life. To avoid these events, it is crucial to precociously identify this condition and to start an apunderwent a surgical procedurepropriate treatment which, depending on the severity of the vascular involvement, might be medical or surgical. CASE PRESENTATION: We report two cases of Loeys-Dietz syndrome precociously diagnosed. The first describes a male, born at 38 + 1 weeks of gestation, with hypotonia, joint hypermobility, arachnodactyly, and fingers joint contractures, as well as senile appearance and facial dysmorphisms. In the suspect of a connective tissue disorder, an echocardiography was performed and revealed an aortic root dilatation of 13 mm (Z score + 3). A trio based Whole Exome Sequencing found a novel de novo variant in the TGFBR2 gene. Despite the onset of a low-dose angiotensin receptor blocker therapy, the aneurysm progressed. The second case describes a female, born at 41 + 3 weeks of gestation. During the neonatal examination a cleft palate was noticed, as well as minor dysmorphisms. Since the family history was suspicious for connective tissue disorders, a genetic panel was performed and identified a pathogenetic variant in TGFB3 gene. In this case, the echocardiography revealed no abnormalities. CONCLUSIONS: In addition to our cases, we identified 14 subjects with neonatal LDS in the medical literature. All of them had aortic involvement. Skeletal and face abnormalities, including eyes and palate malformations, were also highly frequent. Overall, 10 subjects required medical therapy to avoid aneurysm progression, and 8 patients underwent surgical procedures. Benefits of an early diagnosis of LDS are various and imply a potential modification of the natural history of the disease with early interventions on its complications.

Loeys-Dietz syndrome caused by 1q41 deletion including TGFB2 is associated with a neurodevelopmental phenotype.

Loeys-Dietz syndrome (LDS) is a connective tissue disorder that commonly results in a dilated aorta, aneurysms, joint laxity, craniosynostosis, and soft skin that bruises easily. Neurodevelopmental abnormalities are uncommon in LDS. Two previous reports present a total of four patients with LDS due to pure 1q41 deletions involving TGFB2 (Gaspar et al., American Journal of Medical Genetics Part A, 2017, 173, 2289-2292; Lindsay et al., Nature Genetics, 2012, 44, 922-927). The current report describes an additional five patients with similar deletions. Seven of the nine patients present with some degree of hypotonia and gross motor delay, and three of the nine present with speech delay and/or intellectual disability (ID). The smallest deletion common to all patients is a 785 kb locus that contains two genes: RRP15 and TGFB2. Previous studies report that TGFB2 knockout mice exhibit severe perinatal anomalies (Sanford et al., Development, 1997, 124, 2659-2670) and TGFB2 is expressed in the embryonic mouse hindbrain floor (Chleilat et al., Frontiers in Cellular Neuroscience, 2019, 13). The deletion of TGFB2 may be associated with a neurodevelopmental phenotype with incomplete penetrance and variable expression.

[A pedigree study of Loeys-Dietz syndrome type 4 with skeletal deformity related to a novel TGFß2 mutation].

Objective: Loeys-Dietz syndrome is a rare type of hereditary connective tissue disease. This study was aimed to analyze the clinical characteristics and gene mutations in a family of Loeys-Dietz syndrome with skeletal deformity. Methods: Clinical data of the proband and family members were collected and biochemical measurements and radiological examinations were conducted. Genomic DNA was extracted from peripheral blood of the family members. Whole-exome sequencing was performed to determine the mutation sites in the proband, and Sanger sequencing was applied to verify the candidate mutation in the other family members. Results: The proband is a 34-year-old man with deformities of lower extremities for more than 30 years. Physical examinations showed dolichostenomelia, pes planus, joint laxity and scoliosis. Echocardiography revealed the dilatation of aortic root at the level of the sinuses of Valsalva. A heterozygous missense mutation (c. 220A>C, p.Thr74Pro) in exon 1 of TGFß2 gene was identified in the proband. The same mutation was detected in his sister and niece with similar clinical features such as deformities of lower extremities and pes planus. This novel mutation has not been reported in ExAC or 1000G and was predicted to be deleterious, supporting a diagnosis of Loeys-Dietz syndrome type 4. Conclusions: Loeys-Dietz syndrome type 4 is caused by TGFß2 mutations. Skeletal deformity is one of the distinctive features. Genetic testing is helpful for the early diagnosis and differential diagnosis from other connective tissue diseases.

Ocular findings in two Chinese children with Loeys-Dietz syndrome.

BACKGROUND: Loeys-Dietz syndrome (LDS) is a type of connective tissue disease with systemic symptoms similar to Marfan syndrome. Ocular findings are rarely reported especially fundus and extraocular muscles. CASE PRESENTATION: A 6-month old boy with systemic skeletal development delay was found peripheral non-perfusion and neovascularization in the both eyes, and gaven intravitreal injection of ranibizumab and laser. Fundus examination revealed a mild straightening of the temporal vessel in the both eyes. A 22-month old girl with confirmed connective tissue disorder presented to our hospital for strabismus and showed congenital hypoplasia of extraocular muscles. She also had arteriovenous anastomosis in the retinal. The diagnosis of LDS was supported by the genetic DNA examination. CONCLUSION: His is the first report of LDS with congenital hypoplasia of extraocular muscles, meanwhile, ocular examination especially fundus should be paid attention to.