Chiara Dordoni

Clinical and molecular characterization of 40 patients with classic Ehlers–Danlos syndrome: identification of 18 COL5A1 and 2 COL5A2 novel mutations

BackgroundClassic Ehlers–Danlos syndrome (cEDS) is a rare autosomal dominant connective tissue disorder that is primarily characterized by skin hyperextensibility, abnormal wound healing/atrophic scars, and joint hypermobility. A recent study demonstrated that more than 90% of patients who satisfy all of these major criteria harbor a type V collagen (COLLV) defect.MethodsThis cohort included 40 patients with cEDS who were clinically diagnosed according to the Villefranche nosology. The flowchart that was adopted for mutation detection consisted of sequencing the COL5A1 gene and, if no mutation was detected, COL5A2 analysis. In the negative patients the presence of large genomic rearrangements in COL5A1 was investigated using MLPA, and positive results were confirmed via SNP-array analysis.ResultsWe report the clinical and molecular characterization of 40 patients from 28 families, consisting of 14 pediatric patients and 26 adults. A family history of cEDS was present in 9 patients. The majority of the patients fulfilled all the major diagnostic criteria for cEDS; atrophic scars were absent in 2 females, skin hyperextensibility was not detected in a male and joint hypermobility was negative in 8 patients (20% of the entire cohort). Wide inter- and intra-familial phenotypic heterogeneity was observed. We identified causal mutations with a detection rate of approximately 93%. In 25/28 probands, COL5A1 or COL5A2 mutations were detected. Twenty-one mutations were in the COL5A1 gene, 18 of which were novel (2 recurrent). Of these, 16 mutations led to nonsense-mediated mRNA decay (NMD) and to COLLV haploinsufficiency and 5 mutations were structural. Two novel COL5A2 splice mutations were detected in patients with the most severe phenotypes. The known p. (Arg312Cys) mutation in the COL1A1 gene was identified in one patient with vascular-like cEDS.ConclusionsOur findings highlight that the three major criteria for cEDS are useful and sufficient for cEDS clinical diagnosis in the large majority of the patients. The borderline patients for whom these criteria fail can be diagnosed when minor signs of connective tissue diseases and family history are present and when genetic testing reveals a defect in COLLV. Our data also confirm that COL5A1 and COL5A2 are the major, if not the only, genes involved in cEDS.

Differential Diagnosis and Diagnostic Flow Chart of Joint Hypermobility Syndrome/Ehlers-Danlos Syndrome Hypermobility Type Compared to Other Heritable Connective Tissue Disorders

Joint hypermobility syndrome/Ehlers–Danlos syndrome hypermobility type (JHS/EDS‐HT) is an evolving and protean disorder mostly recognized by generalized joint hypermobility and without a defined molecular basis. JHS/EDS‐HT also presents with other connective tissue features affecting a variety of structures and organs, such as skin, eye, bone, and internal organs. However, most of these signs are present in variable combinations and severity in many other heritable connective tissue disorders. Accordingly, JHS/EDS‐HT is an “exclusion” diagnosis which needs the absence of any consistent feature indicative of other partially overlapping connective tissue disorders. While both Villefranche and Brighton criteria include such an exclusion as a mandatory item, a systematic approach for reaching a stringent clinical diagnosis of JHS/EDS‐HT is still lacking. The absence of a consensus on the diagnostic approach to JHS/EDS‐HT concerning its clinical boundaries with similar conditions contribute to limit our actual understanding of the pathologic and molecular bases of this disorder. In this review, we revise the differential diagnosis of JHS/EDS‐HT with those heritable connective tissue disorders which show a significant overlap with the former and mostly include EDS classic, vascular and kyphoscoliotic types, osteogenesis imperfecta, Marfan syndrome, Loeys–Dietz syndrome, arterial tortuosity syndrome, and lateral meningocele syndrome. A diagnostic flow chart is also offered with the attempt to support the less experienced clinician in stringently recognizing JHS/EDS‐HT and stimulate the debate in the scientific community for both management and research purposes.

Gynecologic and obstetric implications of the joint hypermobility syndrome (a.k.a. Ehlers–Danlos syndrome hypermobility type) in 82 Italian patients†‡

Joint hypermobility syndrome (JHS) emerges as likely the most common clinical form of Ehlers–Danlos syndrome. Given the striking predominance of affected women, practitioners often face gynecologic and obstetric issues. However, their decisions are still based on personal experience rather than literature due to the lack of a consistent body of evidence. We collected a set of gynecologic and obstetric features in 82 post‐puberal women with JHS attending two Italian centers. Common gynecologic findings were dysmenorrhea (82.9%), meno/metrorrhagias (53.7%), irregular menses (46.3%), and dispareunia/vulvodinia (31.7%). Forty women were nulliparous and 42 had one or more pregnancy for a total of 93 diagnosed conceptions. Of them, 16.1% were spontaneous abortions, 6.5% voluntary interruptions, 10.7% preterm deliveries, and 66.7% deliveries at term. Overall outcome of proceeding pregnancies was good with no stillbirth and fetal/neonatal hypoxic/ischemic event. Non‐operative vaginal delivery was registered in 72.2%, forceps/vacuum use in 5.5% and cesarean in 22.3%. Local/total anesthesia was successfully performed in 17 pregnancies without any problem. Major post‐partum complications included abnormal scar formation after cesarean or episiotomy (46.1%), hemorrhage (19.4%), pelvic prolapses (15.3%), deep venous thrombosis (4.2%), and coccyx dislocation (1.4%). Prolapses were the most clinically relevant complication and associated with episiotomy. Gathered data were discussed for practically oriented considerations.

Small fiber neuropathy is a common feature of Ehlers-Danlos syndromes

Objective: To investigate the involvement of small nerve fibers in Ehlers-Danlos syndrome (EDS). Methods: Patients diagnosed with EDS underwent clinical, neurophysiologic, and skin biopsy assessment. We recorded sensory symptoms and signs and evaluated presence and severity of neuropathic pain according to the Douleur Neuropathique 4 (DN4) and ID Pain questionnaires and the Numeric Rating Scale (NRS). Sensory action potential amplitude and conduction velocity of sural nerve was recorded. Skin biopsy was performed at distal leg and intraepidermal nerve fiber density (IENFD) obtained and referred to published sex- and age-adjusted normative reference values. Results: Our cohort included 20 adults with joint hypermobility syndrome/hypermobility EDS, 3 patients with vascular EDS, and 1 patient with classic EDS. All except one patient had neuropathic pain according to DN4 and ID Pain questionnaires and reported 7 or more symptoms at the Small Fiber Neuropathy Symptoms Inventory Questionnaire. Pain intensity was moderate (NRS ≥4 and <7) in 8 patients and severe (NRS ≥7) in 11 patients. Sural nerve conduction study was normal in all patients. All patients showed a decrease of IENFD consistent with the diagnosis of small fiber neuropathy (SFN), regardless of the EDS type. Conclusions: SFN is a common feature in adults with EDS. Skin biopsy could be considered an additional diagnostic tool to investigate pain manifestations in EDS.

Recurring and Generalized Visceroptosis in Ehlers–Danlos Syndrome Hypermobility Type

Visceroptosis is described in several heritable connective tissue disorders, including the hypermobility type of Ehlers–Danlos syndrome (hEDS), a.k.a. joint hypermobility syndrome (JHS). Clinical features of hEDS comprise joint hypermobility, mild skin hyperextensibility, joint instability complications, chronic joint/limb pain, and positive family history. Uterine and rectal prolapse has been reported in nulliparous women. We report on a family with two patients with hEDS. The proposita, a 38‐year‐old woman, present bilateral kidney prolapse requiring three nephropexies, gastric ptosis treated with gastropexy and Billroth I gastrectomy, and liver prolapse treated with a non‐codified hepatopexy procedure. Radiological evaluation also showed ovarian and heart prolapse. To our knowledge this is the first case of multiple visceral ptoses in hEDS. Visceral prolapse may lead to severe morbidity, affecting quality of life and a high rate of relapses after surgical procedures. Further investigations are needed to understand the molecular basis of the disease and retrospective studies on surgical outcomes, presentation of case series can be effective in order to offer a better treatment and prevention for hEDS patients.

High prevalence of radiological vertebral fractures in adult patients with Ehlers–Danlos syndrome ☆

Previous studies have reported an increased prevalence of osteoporosis in Ehlers–Danlos syndrome (EDS), but these were limited by a small number of patients and lack of information on fragility fractures. In this crosssectional study, we evaluated the prevalence of radiological vertebral fractures (by quantitative morphometry) and bone mineral density (BMD, at lumbar spine, total hip and femoral neck by dual-energy X-ray absorptiometry) in 52 consecutive patientswith EDS (10 males, 42 females; median age 41 years, range: 21–71; 12with EDS classic type, 37 with EDS hypermobility type, 1 with classic vascular-like EDS, and 2 without specific classification) and 197 control subjects (163 females and 34 males; median age 49 years, range: 26–83) attending an outpatient bone clinic. EDS patients were also evaluated for back pain by numeric pain rating scale (NRS- 11).Vertebral fractures were significantly more prevalent in EDS as compared to the control subjects (38.5% vs. 5.1%; p b 0.001) without significant differences in BMD at either skeletal sites. In EDS patients, the prevalence of vertebral fractures was not significantly (p = 0.72) different between classic and hypermobility types. BMD was not significantly different between fractured and non-fractured EDS patients either at lumbar spine (p = 0.14), total hip (p=0.08), or femoral neck (p=0.21). Severe back pain(≥7 NRS)was more frequent in EDS patients with vertebral fractures as compared to thosewithout fractures (60% vs. 28%; p=0.04). Inconclusion, this is the first study showing high prevalence of vertebral fractures in a relatively large population of EDS patients. Vertebral fractures were associated with more severe back pain suggesting a potential involvement of skeletal fragility in determining poor quality of life. The lack of correlation between vertebral fractures and BMD is consistent with the hypothesis that bone quality may be impaired in EDS.

Further delineation of Loeys-Dietz syndrome type 4 in a family with mild vascular involvement and a TGFB2 splicing mutation

BackgroundThe Loeys-Dietz syndrome (LDS) is a rare autosomal dominant disorder characterized by thoracic aortic aneurysm and dissection and widespread systemic connective tissue involvement. LDS type 1 to 4 are caused by mutations in genes of the TGF-β signaling pathway: TGFBR1 and TGFBR2 encoding the TGF-β receptor (LDS1 and LDS2), SMAD3 encoding the TGF-β receptor cytoplasmic effector (LDS3), and TGFB2 encoding the TGF-β2 ligand (LDS4). LDS4 represents the mildest end of the LDS spectrum, since aneurysms are usually observed in fourth decade and the progression of the disease is slower than in the other forms.Case presentationWe report the clinical and molecular findings of an LDS4 Italian family. Genetic testing included TGFBR1, TGFBR2, SMAD3, and TGFB2 analysis by Sanger sequencing. In order to verify the effect of the identified splice mutation, RT-PCR analysis was performed.The proband, a 57-year-old woman, showed high palate, hypoplasic uvula, easy bruising, joint hypermobility, chronic pain, scoliosis, multiple relapsing hernias, dural ectasia, and mitral valve prolapse. Magnetic resonance angiography revealed tortuosity and ectasia of carotid, vertebral, cerebral, and segmental pulmonary arteries. Arterial aneurysm and dissection never occurred. Her 39- and 34-year-old daughters presented with a variable degree of musculoskeletal involvement. Molecular analysis disclosed the novel c.839-1G>A splice site mutation in the TGFB2 gene. This mutation activates a cryptic splice acceptor site in exon 6 leading to frameshift, premature termination codon and haploinsufficiency (p.Gly280Aspfs*41).ConclusionsOur data confirm that loss-of-function mutations in TGFB2 gene do not always lead to aggressive vascular phenotypes and that articular and skeletal signs are prevalent, therefore suggesting that LDS4 must be considered in patients with sparse signs of LDS and related disorders also in the absence of vascular events.

Arterial Tortuosity Syndrome: homozygosity for two novel and one recurrent SLC2A10 missense mutations in three families with severe cardiopulmonary complications in infancy and a literature review.

BackgroundArterial Tortuosity Syndrome (ATS) is a very rare autosomal recessive connective tissue disorder (CTD) characterized by tortuosity and elongation of the large- and medium-sized arteries and a propensity for aneurysm formation and vascular dissection. During infancy, children frequently present the involvement of the pulmonary arteries (elongation, tortuosity, stenosis) with dyspnea and cyanosis. Other CTD signs of ATS are dysmorphisms, abdominal hernias, joint hypermobility, skeletal abnormalities, and keratoconus. ATS is typically described as a severe disease with high rate of mortality due to major cardiovascular malformations. ATS is caused by mutations in the SLC2A10 gene, which encodes the facilitative glucose transporter 10 (GLUT10). Approximately 100 ATS patients have been described, and 21 causal mutations have been identified in the SLC2A10 gene.Case presentationWe describe the clinical findings and molecular characterization of three new ATS families, which provide insight into the clinical phenotype of the disorder; furthermore, we expand the allelic repertoire of SLC2A10 by identifying two novel mutations. We also review the ATS patients characterized by our group and compare their clinical findings with previous data.ConclusionsOur data confirm that the cardiovascular prognosis in ATS is less severe than previously reported and that the first years of life are the most critical for possible life-threatening events. Molecular diagnosis is mandatory to distinguish ATS from other CTDs and to define targeted clinical follow-up and timely cardiovascular surgical or interventional treatment, when needed.

Insights in the etiopathology of galactosyltransferase II (GalT-II) deficiency from transcriptome-wide expression profiling of skin fibroblasts of two sisters with compound heterozygosity for two novel B3GALT6 mutations

Mutations in B3GALT6, encoding the galactosyltransferase II (GalT-II) involved in the synthesis of the glycosaminoglycan (GAG) linkage region of proteoglycans (PGs), have recently been associated with a spectrum of connective tissue disorders, including spondyloepimetaphyseal dysplasia with joint laxity type 1 (SEMDJL1) and Ehlers–Danlos-like syndrome. Here, we report on two sisters compound heterozygous for two novel B3GALT6 mutations that presented with severe short stature and progressive kyphoscoliosis, joint hypermobility and laxity, hyperextensible skin, platyspondyly, short ilia, and elbow malalignment. Microarray-based transcriptome analysis revealed the differential expression of several genes encoding extracellular matrix (ECM) structural components, including COMP, SPP1, COL5A1, and COL15A1, enzymes involved in GAG synthesis and in ECM remodeling, such as CSGALNACT1, CHPF, LOXL3, and STEAP4, signaling transduction molecules of the TGFβ/BMP pathway, i.e., GDF6, GDF15, and BMPER, and transcription factors of the HOX and LIM families implicated in skeletal and limb development. Immunofluorescence analyses confirmed the down-regulated expression of some of these genes, in particular of the cartilage oligomeric matrix protein and osteopontin, encoded by COMP and SPP1, respectively, and showed the predominant reduction and disassembly of the heparan sulfate specific GAGs, as well as of the PG perlecan and type III and V collagens. The key role of GalT-II in GAG synthesis and the crucial biological functions of PGs are consistent with the perturbation of many physiological functions that are critical for the correct architecture and homeostasis of various connective tissues, including skin, bone, cartilage, tendons, and ligaments, and generates the wide phenotypic spectrum of GalT-II-deficient patients.

Further delineation of FKBP14-related Ehlers-Danlos syndrome: A patient with early vascular complications and non-progressive kyphoscoliosis, and literature review.

FKBP14‐related Ehlers–Danlos syndrome (EDS) is an extremely rare recessive connective tissue disorder described for the first time in 2012 by Baumann and coworkers. The causal gene, FKBP14, encodes a member of the F506‐binding family of peptidyl‐prolyl cis‐trans isomerases. The paucity of patients described so far makes this disorder poorly defined at clinical level. Here, we report an additional pediatric patient, who is compound heterozygous for a recurrent and a novel FKBP14 mutation, and compare his phenotype with those available in literature. This evaluation confirms that kyphoscoliosis (either progressive or non‐progressive), myopathy, joint hypermobility, and congenital hearing loss (sensorineural, conductive, or mixed) are the typical features of the syndrome. Since the patient showed a severe cardiovascular event in childhood and atlantoaxial instability, this report expands the phenotype of the disorder and the allelic repertoire of FKBP14.