Comparative therapeutic strategies for preventing aortic rupture in a mouse model of vascular Ehlers-Danlos syndrome.

Vascular Ehlers-Danlos syndrome is a rare inherited disorder caused by genetic variants in type III collagen. Its prognosis is especially hampered by unpredictable arterial ruptures and there is no therapeutic consensus. We created a knock-in Col3a1+/G182R mouse model and performed a complete genetic, molecular and biochemical characterization. Several therapeutic strategies were also tested. Col3a1+/G182R mice showed a spontaneous mortality caused by thoracic aortic rupture that recapitulates the vascular Ehlers-Danlos syndrome with a lower survival rate in males, thin non-inflammatory arteries and an altered arterial collagen. Transcriptomic analysis of aortas showed upregulation of genes related to inflammation and cell stress response. Compared to water, survival rate of Col3a1+/G182R mice was not affected by beta-blockers (propranolol or celiprolol). Two other vasodilating anti-hypertensive agents (hydralazine, amlodipine) gave opposite results on aortic rupture and mortality rate. There was a spectacular beneficial effect of losartan, reversed by the cessation of its administration, and a marked deleterious effect of exogenous angiotensin II. These results suggest that blockade of the renin angiotensin system should be tested as a first-line medical therapy in patients with vascular Ehlers-Danlos syndrome.

Genome-wide analysis identifies MYH11 compound heterozygous variants leading to visceral myopathy corresponding to late-onset form of megacystis-microcolon-intestinal hypoperistalsis syndrome.

Megacystis-microcolon-hypoperistalsis-syndrome (MMIHS) is a rare and early-onset congenital disease characterized by massive abdominal distension due to a large non-obstructive bladder, a microcolon and decreased or absent intestinal peristalsis. While in most cases inheritance is autosomal dominant and associated with heterozygous variant in ACTG2 gene, an autosomal recessive transmission has also been described including pathogenic bialellic loss-of-function variants in MYH11. We report here a novel family with visceral myopathy related to MYH11 gene, confirmed by whole genome sequencing (WGS). WGS was performed in two siblings with unusual presentation of MMIHS and their two healthy parents. The 38 years-old brother had severe bladder dysfunction and intestinal obstruction, whereas the 30 years-old sister suffered from end-stage kidney disease with neurogenic bladder and recurrent sigmoid volvulus. WGS was completed by retrospective digestive pathological analyses. Compound heterozygous variants of MYH11 gene were identified, associating a deletion of 1.2 Mb encompassing MYH11 inherited from the father and an in-frame variant c.2578_2580del, p.Glu860del inherited from the mother. Pathology analyses of the colon and the rectum revealed structural changes which significance of which is discussed. Cardiac and vascular assessment of the mother was normal. This is the second report of a visceral myopathy corresponding to late-onset form of MMIHS related to compound heterozygosity in MYH11; with complete gene deletion and a hypomorphic allele in trans. The hypomorphic allele harbored by the mother raised the question of the risk of aortic disease in adults. This case shows the interest of WGS in deciphering complex phenotypes, allowing adapted diagnosis and genetic counselling.

Genome-wide association study reveals novel genetic loci: a new polygenic risk score for mitral valve prolapse.

AIMS: Mitral valve prolapse (MVP) is a common valvular heart disease with a prevalence of >2% in the general adult population. Despite this high incidence, there is a limited understanding of the molecular mechanism of this disease, and no medical therapy is available for this disease. We aimed to elucidate the genetic basis of MVP in order to better understand this complex disorder. METHODS AND RESULTS: We performed a meta-analysis of six genome-wide association studies that included 4884 cases and 434 649 controls. We identified 14 loci associated with MVP in our primary analysis and 2 additional loci associated with a subset of the samples that additionally underwent mitral valve surgery. Integration of epigenetic, transcriptional, and proteomic data identified candidate MVP genes including LMCD1, SPTBN1, LTBP2, TGFB2, NMB, and ALPK3. We created a polygenic risk score (PRS) for MVP and showed an improved MVP risk prediction beyond age, sex, and clinical risk factors. CONCLUSION: We identified 14 genetic loci that are associated with MVP. Multiple analyses identified candidate genes including two transforming growth factor-ß signalling molecules and spectrin ß. We present the first PRS for MVP that could eventually aid risk stratification of patients for MVP screening in a clinical setting. These findings advance our understanding of this common valvular heart disease and may reveal novel therapeutic targets for intervention.

Acute decrease of urine calcium by amiloride in healthy volunteers under high-sodium diet.

BACKGROUND: Amiloride is a competitive blocker of the epithelial sodium (Na) channel in the renal collecting duct. It is a less potent diuretic than thiazides or loop diuretics, but is often used in association with its potassium (K)-sparing profile. Whether amiloride has a hypocalciuric effect similar to thiazides remains unclear. Animal studies and experiments on cell lines suggested that amiloride increases calcium (Ca) reabsorption in the distal nephron, but human studies are scarce. METHODS: We performed a post hoc analysis of a study with 48 healthy males (mean ± standard deviation age, 23.2 ± 3.9 years) who were assigned to a high-Na/low-K diet for 7 days before receiving 20 mg of amiloride orally. Urinary excretions of electrolytes were measured at 3 and 6 h afterwards; we calculated the relative changes in urinary excretion rates after amiloride administration. RESULTS: The high-Na/low-K diet led to an expected suppression of plasma renin and aldosterone. Amiloride showed a mild natriuretic effect associated with a decreased kaliuresis. Urinary Ca excretion dropped substantially (by 80%) 3 h after amiloride administration and remained low at the sixth hour. At the same time, fractional excretion of lithium decreased by a third, reflecting an increased proximal tubular reabsorption. CONCLUSIONS: During a high-Na/low-K diet, amiloride had a strong acute hypocalciuric effect, most probably mediated by increased proximal Ca reabsorption, even though a distal effect cannot be excluded. Further studies should establish if chronic amiloride or combined amiloride/thiazide treatment may decrease calciuria more efficiently and be useful in preventing kidney stones.

Cullin 3 Exon 9 Deletion in Familial Hyperkalemic Hypertension Impairs Cullin3-Ring-E3 Ligase (CRL3) Dynamic Regulation and Cycling.

Cullin 3 (CUL3) is the scaffold of Cullin3 Ring E3-ligases (CRL3s), which use various BTB-adaptor proteins to ubiquitinate numerous substrates targeting their proteasomal degradation. CUL3 mutations, responsible for a severe form of familial hyperkalemia and hypertension (FHHt), all result in a deletion of exon 9 (amino-acids 403-459) (CUL3-∆9). Surprisingly, while CUL3-∆9 is hyperneddylated, a post-translational modification that typically activates CRL complexes, it is unable to ubiquitinate its substrates. In order to understand the mechanisms behind this loss-of function, we performed comparative label-free quantitative analyses of CUL3 and CUL3-∆9 interactome by mass spectrometry. It was observed that CUL3-∆9 interactions with COP9 and CAND1, both involved in CRL3 complexes' dynamic assembly, were disrupted. These defects result in a reduction in the dynamic cycling of the CRL3 complexes, making the CRL3-∆9 complex an inactive BTB-adaptor trap, as demonstrated by SILAC experiments. Collectively, the data indicated that the hyperneddylated CUL3-∆9 protein is inactive as a consequence of several structural changes disrupting its dynamic interactions with key regulatory partners.

Spontaneous Cervical Artery Dissection in Vascular Ehlers-Danlos Syndrome: A Cohort Study.

BACKGROUND AND PURPOSE: Vascular Ehlers-Danlos syndrome is a rare inherited connective tissue disorder because of pathogenic variants in the COL3A1 gene. Arterial complications can affect all anatomic areas and about 25% involve supra-aortic trunks (SATs) but no systematic assessment of cervical artery lesions has been made. The primary objective was to determine an accurate prevalence of spontaneous SAT lesions in a large series of patients with vascular Ehlers-Danlos syndrome at diagnosis and during follow-up. Secondary objectives were to study their neurological consequences (transient ischemic attack or stroke) and the possible relationships with sex, genotype, ascertainment status. METHODS: A retrospective review of a monocentric cohort of patients with molecularly proven vascular Ehlers-Danlos syndrome followed in a tertiary referral center from 2000 to 2017. RESULTS: One hundred forty-four patients were analyzed, 56.9% (n=82) had SAT lesions: 64.6% females, 74.4% index-case patients. Most lesions were identified in early arterial assessment (48% at first work-up, mean age of 35.7±13.0 years). Cumulative incidence of a first identification of a SAT lesion was 41.7% at 40 years old. On the complete period of survey, 183 SAT lesions (with 132 dissections and 33 aneurysms) were identified, mainly in internal carotid arteries (56.3%) and vertebral arteries (28.9%), more rarely in patients with COL3A1 null mutations (P=0.008). Transient ischemic attack or stroke were reported in n=16 (19.5%) of the 82 patients with SAT lesions without relation with age, sex, treatment, or hypertension. CONCLUSIONS: Cervical artery lesions are frequent and mostly asymptomatic in patients with vascular Ehlers-Danlos syndrome. Local dissections and aneurysms are the most frequent type of lesions, but transient ischemic attack or stroke seem rare.

Periodontal (formerly type VIII) Ehlers-Danlos syndrome: Description of 13 novel cases and expansion of the clinical phenotype.

Periodontal Ehlers-Danlos syndrome (pEDS) is a rare condition caused by pathogenic variants in the C1R and C1S genes, encoding subunits C1r and C1s of the first component of the classical complement pathway. It is characterized by early-onset periodontitis with premature tooth loss, pretibial hyperpigmentation and skin fragility. Rare arterial complications have been reported, but venous insufficiency is rarely described. Here we report 13 novel patients carrying heterozygous pathogenic variants in C1R and C1S including three novel C1S variants (c.962G > C, c.961 T > G and c.961 T > A). In addition to the pEDS phenotype, three patients and one relative displayed widespread venous insufficiency leading to persistent varicose leg ulcers. One patient suffered an intracranial aneurysm with familial vascular complications including thoracic and abdominal aortic aneurysm and dissection and intracranial aneurysm rupture. This work confirms that vascular complications can occur, although they are not frequent, which leads us to propose to carry out a first complete non-invasive vascular evaluation at the time of the diagnosis in pEDS patients. However, larger case series are needed to improve our understanding of the link between complement pathway activation and connective tissue alterations observed in these patients, and to better assess the frequency, type and consequences of the vascular complications.

Vascular Ehlers-Danlos syndrome (vEDS): CT and histologic findings of pleural and lung parenchymal damage.

OBJECTIVES: To describe CT features of lung involvement in patients with vascular Ehlers-Danlos syndrome (vEDS), a rare genetic condition caused by pathogenic variants within the COL3A1 gene, characterized by recurrent arterial, digestive, and pulmonary events. MATERIAL AND METHODS: All consecutive vEDS patients referred to the national tertiary referral center for vEDS, between 2004 and 2016, were included. Chest CT scans obtained during the initial vascular work-up were reviewed retrospectively by two chest radiologists for lung involvement. Five surgical samples underwent histologic examination. RESULTS: Among 136 enrolled patients (83 women, 53 men; mean age 37 years) with molecularly confirmed vEDS, 24 (17.6%) had a history of respiratory events: 17 with pneumothorax, 4 with hemothorax, and 3 with hemoptysis that required thoracic surgery in 11. CT scans detected lung parenchymal abnormalities in 78 (57.3%) patients: emphysema (mostly centrilobular and paraseptal) in 44 (32.3%), comparable for smokers and non-smokers; clusters of calcified small pulmonary nodules in 9 (6.6%); and cavitated nodules in 4 (2.9%). Histologic examination of surgical samples found arterial abnormalities, emphysema with alveolar ruptures in 3, accompanied by diffuse hemorrhage and increased hemosiderin resorption. CONCLUSION: In vEDS patients, identification of lung parenchymal abnormalities is common on CT. The most frequently observed CT finding was emphysema suggesting alveolar wall rupture which might facilitate the diagnostic screening of the disease in asymptomatic carriers of a genetic COL3A1 gene mutation. The prognostic value and evolution of these parenchymal abnormalities remain to be evaluated. KEY POINTS: • Patients with vEDS can have lung parenchymal changes on top of or next to thoracal vascular abnormalities and that these changes can be present in asymptomatic cases. • The presence of these parenchymal changes is associated with a slightly higher incidence of respiratory events (although not statistically significant). • Identification of the described CT pattern by radiologists and chest physicians may facilitate diagnostic screening.

Mutations in DCHS1 cause mitral valve prolapse.

Mitral valve prolapse (MVP) is a common cardiac valve disease that affects nearly 1 in 40 individuals. It can manifest as mitral regurgitation and is the leading indication for mitral valve surgery. Despite a clear heritable component, the genetic aetiology leading to non-syndromic MVP has remained elusive. Four affected individuals from a large multigenerational family segregating non-syndromic MVP underwent capture sequencing of the linked interval on chromosome 11. We report a missense mutation in the DCHS1 gene, the human homologue of the Drosophila cell polarity gene dachsous (ds), that segregates with MVP in the family. Morpholino knockdown of the zebrafish homologue dachsous1b resulted in a cardiac atrioventricular canal defect that could be rescued by wild-type human DCHS1, but not by DCHS1 messenger RNA with the familial mutation. Further genetic studies identified two additional families in which a second deleterious DCHS1 mutation segregates with MVP. Both DCHS1 mutations reduce protein stability as demonstrated in zebrafish, cultured cells and, notably, in mitral valve interstitial cells (MVICs) obtained during mitral valve repair surgery of a proband. Dchs1(+/-) mice had prolapse of thickened mitral leaflets, which could be traced back to developmental errors in valve morphogenesis. DCHS1 deficiency in MVP patient MVICs, as well as in Dchs1(+/-) mouse MVICs, result in altered migration and cellular patterning, supporting these processes as aetiological underpinnings for the disease. Understanding the role of DCHS1 in mitral valve development and MVP pathogenesis holds potential for therapeutic insights for this very common disease.

Classical Ehlers-Danlos syndrome with a propensity to arterial events: A new report on a French family with a COL1A1 p.(Arg312Cys) variant.

Ehlers-Danlos syndromes (EDS) are a clinically and genetically heterogeneous group of connective tissue disorders. Overlapping features including arterial aneurysms/dissections in both classical and vascular EDS are a major challenge in the clinical diagnosis of these subtypes. The COL1A1 p.(Arg312Cys) variant leads to a phenotype of classical EDS with a propensity to arterial complications. Our report describes a two-generation family with one individual presenting with a dissection of the right external iliac artery. The primary suspicion of vascular EDS with the unsatisfactory identification of a COL3A1 benign variant was secondarily readjusted with the identification of COL1A1 p.(Arg312Cys) variant. This raises the question of the association of COL1A1 p.(Arg312Cys) with arterial complications and the need for a gene panel including not only the usual genes tested in search of classical or vascular EDS but also COL1A1.

Prognostic value of the 12-lead surface electrocardiogram in sarcomeric hypertrophic cardiomyopathy: data from the REMY French register.

AIMS: To identify independent electrocardiogram (ECG) predictors of long-term clinical outcome based on standardized analysis of the surface ECG in a large multicentre cohort of patients with sarcomeric hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS: Retrospective observational study from the REMY French HCM clinical research observatory. Primary endpoint was a composite of all-cause mortality, major non-fatal arrhythmic events, hospitalization for heart failure (HF), and stroke. Secondary endpoints were components of the primary endpoint. Uni- and multivariable Cox proportional hazard regression analysis was performed to identify independent predictors. Among 994 patients with HCM, only 1.8% had a strictly normal baseline ECG. The most prevalent abnormalities were inverted T waves (63.7%), P-wave abnormalities (30.4%), and abnormal Q waves (25.5%). During a mean follow-up of 4.0 ± 2.0 years, a total of 272 major cardiovascular events occurred in 217 patients (21.8%): death or heart transplant in 98 (9.8%), major arrhythmic events in 40 (4.0%), HF hospitalization in 115 (11.6%), and stroke in 23 (2.3%). At multivariable analysis using ECG covariates, prolonged QTc interval, low QRS voltage, and PVCs of right bundle branch block pattern predicted worse outcome, but none remained independently associated with the primary endpoint after adjustment on main demographic and clinical variables. For secondary endpoints, abnormal Q waves independently predicted all-cause death [hazard ratio (HR) 2.35, 95% confidence interval (CI) 1.23-4.47; P = 0.009] and prolonged QTc the risk of HF hospitalization (HR 1.006, 95% CI 1.001-1.011; P = 0.024). CONCLUSION: The 12-lead surface ECG has no independent value to predict the primary outcome measure in patients with HCM. The 12-lead surface ECG has been widely used as a screening tool in HCM but its prognostic value remains poorly known. The value of baseline surface ECG to predict long-term clinical outcomes was studied in a cohort of 994 patients with sarcomeric HCM. The surface ECG has no significant additional value to predict outcome in this patient population.

Communication of genetic information to at-risk relatives during the multidisciplinary monitoring of vascular Ehlers-Danlos syndrome in a French referral clinic.

Vascular Ehlers-Danlos syndrome (vEDS) is a rare inherited disorder leading to arterial, digestive, and uterine complications due to pathogenic COL3A1 variants. Identification of causal variants allows family screening, provided that relatives have previously been informed, according to a 2013 French Decree. The aims of our study were to assess the communication of genetic information to at-risk relatives, the impact of diagnosis disclosure and to highlight a possible link between the experience of vEDS patients and ability to communicate about genetic information. A total of n = 51 vEDS adult probands answered a questionnaire during a clinical visit. Communication to relatives was considered effective if the proband gave information to some or all first-degree relatives and considered easily achieved if it was disclosed to all relatives less than a month after the diagnosis and without difficulty. Personal and family vEDS experiences of probands were also assessed. Effective communication of information to relatives was remarkably high (98%). Siblings were the most frequently informed relatives (82%). Women informed their at-risk relatives of genetic family screening faster (p = .006) and easier (p = .004) than men. There was no difference in the disclosure of information to relatives before and after 2013 in our multidisciplinary clinic. Regarding the lived experience of vEDS patients, they felt anxious (78%) at diagnosis disclosure but also considered this diagnosis as an opportunity to start a medical follow-up (82%) putting an end to diagnosis delay. Our findings highlight for the first time that the ability to easily inform at-risk first-degree relatives is related to the relief felt during vEDS-positive diagnosis disclosure (p = .04). In order to improve the communication of genetic information to relatives, we believe that psychological support should systematically be part of the multidisciplinary monitoring, just as medical follow-up and genetic counseling.

Severe Arterial Hypertension from Cullin 3 Mutations Is Caused by Both Renal and Vascular Effects.

BACKGROUND: Mutations in four genes, WNK lysine deficient protein kinase 1 and 4 (WNK1 and WNK4), kelch like family member 3 (KLHL3), or Cullin 3 (CUL3), can result in familial hyperkalemic hypertension (FHHt), a rare Mendelian form of human arterial hypertension. Although all mutations result in an increased abundance of WNK1 or WNK4, all FHHt-causing CUL3 mutations, resulting in the skipping of exon 9, lead to a more severe phenotype. METHODS: We created and compared two mouse models, one expressing the mutant Cul3 protein ubiquitously (pgk-Cul3∆9) and the other specifically in vascular smooth muscle cells (SM22-Cul3∆9). We conducted pharmacologic investigations on isolated aortas and generated stable and inducible HEK293 cell lines that overexpress the wild-type Cul3 or mutant Cul3 (Cul3∆9) protein. RESULTS: As expected, pgk-Cul3∆9 mice showed marked hypertension with significant hyperkalemia, hyperchloremia and low renin. BP increased significantly in SM22-Cul3∆9 mice, independent of any measurable effect on renal transport. Only pgk-Cul3∆9 mice displayed increased expression of the sodium chloride cotransporter and phosphorylation by the WNK-SPAK kinases. Both models showed altered reactivity of isolated aortas to phenylephrine and acetylcholine, as well as marked acute BP sensitivity to the calcium channel blocker amlodipine. Aortas from SM22-Cul3∆9 mice showed increased expression of RhoA, a key molecule involved in regulation of vascular tone, compared with aortas from control mice. We also observed increased RhoA abundance and t1/2 in Cul3∆9-expressing cells, caused by decreased ubiquitination. CONCLUSIONS: Mutations in Cul3 cause severe hypertension by affecting both renal and vascular function, the latter being associated with activation of RhoA.

Resistance to Insulin in Patients with Gitelman Syndrome and a Subtle Intermediate Phenotype in Heterozygous Carriers: A Cross-Sectional Study.

BACKGROUND: Gitelman syndrome is a salt-losing tubulopathy caused by mutations in the SLC12A3 gene, which encodes the thiazide-sensitive sodium-chloride cotransporter. Previous studies suggested an intermediate phenotype for heterozygous carriers. METHODS: To evaluate the phenotype of heterozygous carriers of pathogenic SLC12A3 mutations, we performed a cross-sectional study of patients with Gitelman syndrome, heterozygous carriers, and healthy noncarriers. Participants measured their BP at home for three consecutive days before hospital admission for blood and urine sampling and an oral glucose tolerance test. RESULTS: We enrolled 242 participants, aged 18-75 years, including 81 heterozygous carriers, 82 healthy noncarriers, and 79 patients with Gitelman syndrome. The three groups had similar age, sex ratio, and body mass index. Compared with healthy noncarriers, heterozygous carriers showed significantly higher serum calcium concentration (P=0.01) and a trend for higher plasma aldosterone (P=0.06), but measures of home BP, plasma and urine electrolytes, renin, parathyroid hormone, vitamin D, and response to oral glucose tolerance testing were similar. Patients with Gitelman syndrome had lower systolic BP and higher heart rate than noncarriers and heterozygote carriers; they also had significantly higher fasting serum glucose concentration, higher levels of markers of insulin resistance, and a three-fold higher sensitivity to overweight. According to oral glucose tolerance testing, approximately 14% of patients with Gitelman syndrome were prediabetic, compared with 5% of heterozygous carriers and 4% of healthy noncarriers. CONCLUSIONS: Heterozygous carriers had a weak intermediate phenotype, between that of healthy noncarriers and patients with Gitelman syndrome. Moreover, the latter are at risk for development of type 2 diabetes, indicating the heightened importance of body weight control in these patients.

High-throughput sequencing contributes to the diagnosis of tubulopathies and familial hypercalcemia hypocalciuria in adults.

Hereditary tubulopathies are rare diseases with unknown prevalence in adults. Often diagnosed in childhood, hereditary tubulopathies can nevertheless be evoked in adults. Precise diagnosis can be difficult or delayed due to insidious development of symptoms, comorbidities and polypharmacy. Here we evaluated the diagnostic value of a specific panel of known genes implicated in tubulopathies in adult patients and compared to our data obtained in children. To do this we analyzed 1033 non-related adult patients of which 744 had a clinical diagnosis of tubulopathy and 289 had a diagnosis of familial hypercalcemia with hypocalciuria recruited by three European reference centers. Three-quarters of our tubulopathies cohort included individuals with clinical suspicion of Gitelman syndrome, kidney hypophosphatemia and kidney tubular acidosis. We detected pathogenic variants in 26 different genes confirming a genetic diagnosis of tubulopathy in 29% of cases. In 16 cases (2.1%) the genetic testing changed the clinical diagnosis. The diagnosis of familial hypercalcemia with hypocalciuria was confirmed in 12% of cases. Thus, our work demonstrates the genetic origin of tubulopathies in one out of three adult patients, half of the rate observed in children. Hence, establishing a precise diagnosis is crucial for patients, in order to guide care, to survey and prevent chronic complications, and for genetic counselling. At the same time, this work enhances our understanding of complex phenotypes and enriches the database with the causal variants described.

Frequency of de novo variants and parental mosaicism in vascular Ehlers-Danlos syndrome.

PURPOSE: Vascular Ehlers-Danlos syndrome (vEDS) is a rare inherited autosomal dominant disorder caused by COL3A1 pathogenic variants. A high percentage of de novo cases has been suggested. Part of it could be due to parental mosaicism, but its frequency is unknown. METHODS: This retrospective study included a large series of COL3A1-confirmed vEDS probands with family information. The frequency of de novo cases was evaluated and the distribution of the type of variants was compared according to the mode of inheritance. The COL3A1 mosaicism was studied by deep targeted next- generation sequencing (NGS) from parental blood DNA. RESULTS: Out of 177 vEDS probands, 90 had a negative family history, suggesting a high rate (50.8%) of de novo pathogenic variants, enriched in the more severe COL3A1 variants (no null variant). Among those, both parental DNA were available in 36 cases and one parental DNA in 18 cases. NGS detected only one mosaicism from maternal blood DNA (allelic ratio 18%), which was confirmed in saliva (allelic ratio 22%). CONCLUSION: vEDS is characterized by a high frequency of de novo pathogenic variants. Parental mosaicism is rare (2-3%), but should be systematically searched with targeted NGS, taking into account its importance in genetic counseling.

Correction: Arterial tortuosity syndrome: 40 new families and literature review.

In the published version of this paper the author Neus Baena's name was incorrectly given as Neus Baena Diez. This has now been corrected in both the HTML and PDF versions of the paper.

FLNC pathogenic variants in patients with cardiomyopathies: Prevalence and genotype-phenotype correlations.

Pathogenic variants in FLNC encoding filamin C have been firstly reported to cause myopathies, and were recently linked to isolated cardiac phenotypes. Our aim was to estimate the prevalence of FLNC pathogenic variants in subtypes of cardiomyopathies and to study the relations between phenotype and genotype. DNAs from a cohort of 1150 unrelated index-patients with isolated cardiomyopathy (700 hypertrophic, 300 dilated, 50 restrictive cardiomyopathies, and 100 left ventricle non-compactions) have been sequenced on a custom panel of 51 cardiomyopathy disease-causing genes. An FLNC pathogenic variant was identified in 28 patients corresponding to a prevalence ranging from 1% to 8% depending on the cardiomyopathy subtype. Truncating variants were always identified in patients with dilated cardiomyopathy, while missense or in-frame indel variants were found in other phenotypes. A personal or family history of sudden cardiac death (SCD) was significantly higher in patients with truncating variants than in patients carrying missense variants (P = .01). This work reported the first observation of a left ventricular non-compaction associated with a unique probably causal variant in FLNC which highlights the role of FLNC in cardiomyopathies. A correlation between the nature of the variant and the cardiomyopathy subtype was observed as well as with SCD risk.

Natural History and Surgical Management of Colonic Perforations in Vascular Ehlers-Danlos Syndrome: A Retrospective Review.

BACKGROUND: Vascular Ehlers-Danlos syndrome is a rare and severe genetic condition leading to spontaneous, potentially life-threatening arterial and digestive complications. Colonic ruptures are a common feature of the disease, but clear recommendations on their management are lacking. OBJECTIVE: This study aimed to identify surgery-related morbidity and 30-day postoperative mortality after colonic perforation. DESIGN: This was a retrospective review. SETTING: A large cohort of patients with vascular Ehlers-Danlos syndrome was followed in a tertiary referral center. PATIENTS: Between 2000 and 2016, the French National Reference Centre for Rare Vascular Diseases (HEGP, AP-HP, Paris, France) followed 148 patients with molecularly proven vascular Ehlers-Danlos syndrome. MAIN OUTCOME MEASURES: The primary outcomes measured were surgery-related morbidity and 30-day postoperative mortality. RESULTS: Of 133 patients with molecularly proven vascular Ehlers-Danlos syndrome, 30 (22%) had a history of colonic perforation and 15 (50%) were males. These subjects were diagnosed with vascular Ehlers-Danlos syndrome at a younger age than patients with a history of GI events without colonic perforation (p = 0.0007). There were 46 colonic perforations, median 1.0 event per patient (interquartile range, 1.0-2.0). Reperforations occurred in 14 (47%) patients, mostly males. Surgical management consisted of Hartmann procedures or subtotal abdominal colectomies, with a nonnegligible rate of reperforation following partial colonic resection (11 patients, 41%). LIMITATIONS: The main limitations of this work are its retrospective design and that the diagnosis of vascular Ehlers-Danlos syndrome was made after colonic perforations in a majority of patients. CONCLUSION: Colonic perforations seem more severe in males, with a high rate of reperforation after Hartmann procedure. Subtotal colectomy may reduce digestive morbidity, particularly in male patients. Additional studies are required to identify other predictors of reperforation. See Video Abstract at http://links.lww.com/DCR/A937.

Pseudoxanthoma elasticum with prominent arterial calcifications evoking CD73 deficiency.

Pseudoxanthoma elasticum (PXE) is a rare disorder characterized by skin, eye, and cardiovascular lesions due to ectopic mineralization and fragmentation of elastic fibers of connective tissues. We present an atypical case of PXE with diffuse vascular calcification and negligible skin and eye lesions. The patient was a 37-year-old man suffering from severe bilateral arterial calcifications in superficial femoral and posterior tibial arteries. Eye fundoscopy and skin examination were first considered normal. This phenotype suggested first the diagnosis of Arterial Calcification due to Deficiency of CD73 (ACDC) characterized by mutations in NT5E gene. However, we found two variants in ABCC6 gene, and no variant in NT5E. Skin reexamination revealed few lateral skin papules confined to the scalp. Phenotypic overlap was described in vascular calcification disorders, between GACI and PXE phenotypes, and we discuss here expansion of this overlap, including ACDC phenotype. Identification of these expanding and overlapping phenotypes was enabled by genetic screening of the corresponding genes, in a systematic approach. We propose to create a calcification next generation sequencing (NGS) panel with NT5E, GGCX, ENPP1, and ABCC6 genes to improve the molecular diagnosis of vascular calcification.