Ascertainment and severity of Marfan syndrome in a Scottish population

A population-based survey of FBN1 variants in Iceland reveals underdiagnosis of Marfan syndrome

Marfan syndrome (MFS) is an autosomal dominant condition characterized by aortic aneurysm, skeletal abnormalities, and lens dislocation, and is caused by variants in the FBN1 gene. To explore causes of MFS and the prevalence of the disease in Iceland we collected information from all living individuals with a clinical diagnosis of MFS in Iceland (n = 32) and performed whole-genome sequencing of those who did not have a confirmed genetic diagnosis (27/32). Moreover, to assess a potential underdiagnosis of MFS in Iceland we attempted a genotype-based approach to identify individuals with MFS. We interrogated deCODE genetics' database of 35,712 whole-genome sequenced individuals to search for rare sequence variants in FBN1. Overall, we identified 15 pathogenic or likely pathogenic variants in FBN1 in 44 individuals, only 22 of whom were previously diagnosed with MFS. The most common of these variants, NM_000138.4:c.8038 C > T p.(Arg2680Cys), is present in a multi-generational pedigree, and was found to stem from a single forefather born around 1840. The p.(Arg2680Cys) variant associates with a form of MFS that seems to have an enrichment of abdominal aortic aneurysm, suggesting that this may be a particularly common feature of p.(Arg2680Cys)-associated MFS. Based on these combined genetic and clinical data, we show that MFS prevalence in Iceland could be as high as 1/6,600 in Iceland, compared to 1/10,000 based on clinical diagnosis alone, which indicates underdiagnosis of this actionable genetic disorder.

Incidence and de novo mutation rate of Marfan syndrome and risk of ectopia lentis

PURPOSE

To investigate the population-based incidence and de novo mutation rate of Marfan syndrome and risk of ectopia lentis.

METHODS

Patients newly diagnosed with Marfan syndrome in Olmsted County, Minnesota, from January 1, 1976, through December 31, 2005, were identified through medical records review. Outcome measures were Marfan incidence, de novo mutation rate, risk of ectopia lentis.

RESULTS

Marfan syndrome was identified in 17 patients during the 30-year period, yielding an incidence of 0.52 per 100,000 people/year (95% CI, 0.27-0.77). Mean age at diagnosis was 24.4 years (range, 1.7 year to 51.3 years). Nine patients (53%) were female. Of the 17, 5 (29%) were new mutations, with a calculated mutation rate of 3.8 ± 1.7 × 10-5. Four (24%) were diagnosed with ectopia lentis, including 3 at the time of their Marfan diagnosis. Of the 14 patients at risk for developing ectopia lentis after being diagnosed with Marfan syndrome, 1 (7%) developed it during a mean follow-up of 9 years (range, 0-6.4). Twelve (71%) were diagnosed with dilated ascending aorta during a mean follow-up of 13.2 years (range, 6.7 months to 28.9 years).

CONCLUSIONS

Incidence and de novo mutation rate of Marfan syndrome in this population-based cohort was higher than prior reports. Ectopia lentis, whose prevalence in North America has not been reported previously, occurred in approximately one-fourth of study patients and more commonly around the time of initial Marfan diagnosis.

Health-Related Quality of Life of Patients with Marfan Syndrome-Polish Study

Background: Despite extensive knowledge about the quality of life of people suffering from rare diseases, data on patients with Marfan syndrome (MFS) are scarce and inconsistent. Hence, the problem of assessing the quality of life (QOL) and its relationship with the assessment of which ailments are the most burdensome for these patients is still open. Aim: Comparison of the quality of life of patients with MFS and determination as to which of the reported complaints in patients with MFS are related to the QOL of patients. Methods: The study included 35 patients with MFS and 35 healthy controls, matched for gender and age. In the study, the questionnaire of quality of life assessment SF-36 was used to assess the level of health-related quality of life, as well as an interview of the most severe symptoms reported by patients with MFS. Results: The level of the physical dimension of the QOL (p < 0.001) and limiting of roles due to physical health (p = 0.002), as well as the level of general index of the QOL (p < 0.001), were statistically significantly lower in MFS patients when compared to controls. People from both studied groups do not vary in the scope of pain, vitality, social functioning, limiting the roles due to emotional problems, and state of mind but also in the mental dimension of the health-related quality of life (HRQL). Additionally, there has been a correlation between HRQL and the subjective assessment of the effects of orthopedic, ophthalmic, and cardiological problems in life, as well as lower exercise tolerance in the evaluation of people with MFS and QOL in most areas. Conclusions: Patients with MFS present a reduced QOL in the areas of physical functioning, limiting roles due to physical health, general feeling of general health, the physical dimension of the HRQL, and the general index of the QOL; in these areas, they require careful evaluation, as well as medical and psychosocial assistance.

Symptomatic mosaicism for a novel FBN1 splice site variant in a parent causing inherited neonatal Marfan syndrome

Neonatal Marfan syndrome is a severe, early onset presentation of pathogenic variants in FBN1. Because of the significant cardiac involvement and early mortality, nearly all reported cases have been de novo, and the disorder has not been documented to be inherited from a symptomatic parent. Here, we present a female infant with neonatal Marfan syndrome who was born to a father with Marfan syndrome. Prior to the birth of his daughter, the father had been found to have an FBN1 missense variant of uncertain clinical significance. Initial familial variant testing of the infant did not reveal the same missense variant, but Sanger sequencing of FBN1 subsequently identified a pathogenic splice site variant. The father was then found to have 10%-20% mosaicism for the same splice site variant.

Pleural changes in patients with pneumothoraces and Marfan syndrome

Background

Patients with Marfan syndrome (MFS) often develop pneumothorax, but the features of pneumothorax in the context of MFS have not been well described in the literature. We clarified the clinical and histopathological characteristics of this condition in these patients.

Methods

Patients with MFS were selected from among all patients who underwent surgery for pneumothorax, between December 1991 and January 2015, in our hospital. We studied the histopathological characteristics of the resected lungs as well as the clinical features of the selected patients, including surgical findings and postoperative recurrence status.

Results

There were 966 operations underwent pneumothorax-related surgeries in our hospital. A total of 16 operations (1.66%) were performed on patients with MFS in 11 cases. In this study, 9 patients (6 men, 3 women) were included. Clinically, 7 patients (77.8%) had bilateral pneumothoraces and 4 (44.4%) exhibited postoperative recurrent pneumothoraces. Pathologically, the resected pulmonary bullae exhibited blood vessel cystic medial degeneration (55.6% of cases), calcification (55.6% of cases), and demonstrated elastic fiber fragmentation and degeneration (all cases).

Conclusions

As in few previous reports, many patients with MFS develop bilateral or postoperative recurrent pneumothoraces. In many patients, characteristic changes in the pulmonary bullae, possibly caused by degenerated elastic fibers, were observed.

<p>Ocular Manifestations and Biometrics in Marfan’s Syndrome from Eastern Nepal</p>

Purpose

To evaluate the ocular characteristics of Marfan’s syndrome (MFS) fulfilling the revised Ghent-2 nosology in Eastern Nepal.

Materials and Methods

A hospital-based observational and cross-sectional study was conducted. Ocular manifestations and biometrics were incorporated. Patients were subdivided into adults (16 years or older) and children (5–15 years). Ocular biometric parameters consisted of values of refractive error, keratometry readings, anterior chamber depth (ACD), central corneal thickness (CCT), lens thickness (LT) and axial length (AL).

Results

A total of 34 eyes of 17 patients with MFS were included, where 32 eyes were phakic. Mean age of the study participants was 14.5 ± 9.1 years. The mean best corrected visual acuity (BCVA) of phakic eyes was 0.99 ± 0.82 LogMAR. Myopia greater than −3 diopters (D) was present in 28/34 (82.35%) eyes. The average spherical equivalent was −12.34 ± 8.85 D. Ectopia lentis (EL) was present in 24/32 (75%) eyes where superonasal was the most common subluxation in 10/24 (41.7%) eyes. AL was longer in adults 26.54 ± 4.42 mm compared to 25.21 ± 1.93 mm in children. Likewise, LT in adults was 4.9 ± 0.70 mm and 4.40 ± 0.59 mm in pediatric participants. Flat corneas were noted in both the groups with an average of 41.53 ± 2.21 D. The mean CCT and ACD were 524.62 ± 21.74 μm and 3.64 ± 0.80 mm, respectively. There was a negative association between the AL and the average corneal curvature (K_med, correlation coefficient −0.11, p=0.54).

Conclusion

Myopia is the foremost ocular involvement with significant visual disability in MFS. Though, AL and corneal curvature are not included in the revised Ghent-2 nosology, we strongly recommend these parameters to be considered during ophthalmic evaluation in suspected and diagnosed cases of MFS in the absence of genetic testing.

Oral health in patients with Marfan syndrome

INTRODUCTION

The role of this study is to highlight a correlation between patients with Marfan syndrome and oral health status by evaluating and reviewing the relevant scientific literature. The syndrome is characterized by an abnormal production of the fibrillin1 protein. The manifestations of Marfan syndrome affect organs that contain connective tissue such as the skeletal system, the eyes, the heart and the blood vessels, the lungs and the fibrous membranes that cover the brain and the spine. The facial bony and soft structures can therefore be affected, influencing the stage of tooth formation and the structure of the teeth, we also want to analyze in this study, the periodontal complications and the management of the latter, with the use of surgical techniques that include the use of biomaterials.

MATERIALS AND METHODS

A comprehensive review of the literature was conducted according to PRISMA guidelines. After a careful analysis of the work obtained by two independent academics, there have been 18. All data from the studies were compared and many of these highlighted the presence of abnormalities in the oral district.

RESULTS

The studies taken into consideration a whole series of oral manifestations related to the Marfan syndrome. Oral mucosa, periodontal, dental abnormalities, bone abnormalities or joint dysfunction are frequently involved in patients affected by this disease.

CONCLUSIONS

All the research have given positive results in terms of dental or oral anomalies. This information may be essential to limit and intervene early improving the oral health of syndromic patients.

Full-Mouth Rehabilitation With Implant-Prosthesis in Marfan Syndrome Patient: Clinical Report and Literature Review

The purpose of this case report is to present implant-retained maxillary and mandibular complete overdentures in a patient with Marfan syndrome. The patient initially presented with generalized periodontitis (stage IV, grade C). Due to the progressive nature of periodontal disease, the patient elected to have implant-retained maxillary and mandibular complete dentures. Bilateral maxillary sinus augmentation was performed 6 months before full-mouth extraction, alveoloplasty, and immediate implant placement. Maxillary and mandibular immediate overdentures were delivered. After 4 months of healing, the final overdenture was fabricated. The patient was seen regularly throughout the healing process for peri-implant maintenance. Soft-tissue grafts were completed to increase the thickness of the mucosa around the implants. The patient has been followed for 2 years and is functioning well without major complications. For patients with Marfan syndrome, implant-retained prostheses are a viable treatment option in the presence of a failing dentition.

Variability in gene-based knowledge impacts variant classification: an analysis of FBN1 missense variants in ClinVar

Gene-specific knowledge can enhance genetic variant classification, but may not be routinely incorporated into clinical laboratory practice. For example, FBN1 variants associated with Marfan syndrome may be variably classified depending on knowledge of FBN1-specific critical regions. In order to assess variability in classification of FBN1 variants, 674 FBN1 missense variants from 18 ClinVar submitters were compared and reanalyzed using FBN1-specific criteria and ACMG/AMP 2015 guidelines for variant interpretation. Conflicting variant classifications occurred in 30.7% of the missense variants that had multiple submitters. There were 451 classifications of 361 critical residue missense variants, with 80.0% (361/451) classified as likely pathogenic or pathogenic [(L)P]. Non-cysteine critical residue variants were less likely to be classified as (L)P [55.3% (78/141)] than cysteine variants [91.3% (283/310)] and were more likely to lack evidence citing the functional significance of the amino acid impacted. Application of FBN1-specific knowledge allowed for reclassification or discrepancy resolution in 65/361 (18.0%) critical residue variants. There were 522 classifications of 313 unique missense variants not known to impact a critical residue. Of these, 31.6% (165/522) were likely overclassified as either (L)P or uncertain significance (VUS), especially when minor allele frequency (MAF) was taken into account, and we reclassified or resolved classification discrepancies in 128/313 (40.9%) of these variants. Our results provide a refined framework and resource for FBN1 variant classification, and further supports the more global implications of combining gene-based knowledge with ACMG/AMP criteria and appropriate MAF cutoffs for variant classification that extend beyond FBN1.

Application of next-generation sequencing to screen for pathogenic mutations in 123 unrelated Chinese patients with Marfan syndrome or a related disease

Marfan syndrome (MFS) is a systemic connective tissue disease principally affecting the ocular, skeletal and cardiovascular systems. This autosomal dominant disorder carries a prevalence of 1:3,000 to 1:5,000. This study aims to define the mutational spectrum of MFS related genes in Chinese patients and to establish genotype-phenotype correlations in MFS. Panel-based targeted next-generation sequencing was used to analyze the FBN1, TGFBR1 and TGFBR2 genes in 123 unrelated Chinese individuals with MFS or a related disease. Genotype-phenotype correlation analyses were performed in mutation-positive patients. The results showed that 97 cases/families (78.9%; 97/123) harbor at least one (likely) pathogenic mutation, most of which were in FBN1; four patients had TGFBR1/2 mutations; and one patient harbored a SMAD3 mutation. Three patients had two FBN1 mutations, and all patients showed classical MFS phenotypes. Patients with a dominant negative-FBN1 mutation had a higher prevalence of ectopia lentis (EL). Patients carrying a haploinsufficiency-FBN1 mutation tended to have aortic dissection without EL. This study extends the spectrum of genetic backgrounds of MFS and enriches our knowledge of genotype-phenotype correlations.

Obstructive sleep apnea in children with Marfan syndrome: Relationships between three-dimensional palatal morphology and apnea-hypopnea index

OBJECTIVE

To evaluate the relationship between the severity degree of OSA (apnea/hypopnea index AHI>1) and palatal area and volume, measured by 3D analysis of digital casts in Marfan children.

METHODS

Twenty children with a clinical diagnosis of MS were recruited from a tertiary medical center. All the subjects underwent standard nocturnal polygraphy testing. Sixteen Marfan patients (7F,9 M; mean age 8.8yy ± 1.5yy) with AHI>1 were enrolled. Marfan Group (MG) was compared with a control group (CG) of 17 children without Marfan syndrome (9F,8 M; mean age 8.5yy ± 1.7yy) presenting with nose-breathing pattern. For each subject maxillary digital casts were taken and palatal area and volume were measured. Unpaired t-test was used to test significant differences between MG and CG for area and volume measurements. Pearson correlation coefficient (PCC) was used to measure the linear correlation between the degree of OSA (AHI index) and palatal volume and palatal area.

RESULTS

80% of Marfan children presented an AHI>1 and a diagnosis of OSA. MG presented statistically significant lower values of palatal surface area (662.68 mm²; P < 0.0001) and palatal volume (2578.1 mm³; P < 0.0001) with respect to CG (923.0 mm² and 3756.6 mm³, respectively). Correlation analysis showed that AHI index had no linear correlation with palatal area (r = - 0,07) and with palatal volume (r = - 0,11).

CONCLUSION

OSA is highly prevalent in children with Marfan's syndrome (80%). Marfan children present a reduction of palatal area and volume when compared to healthy subjects. OSA in Marfan children is not linear correlated to the palatal morphology and it shows a multifactorial aetiology.

Age Differences in Axial Length, Corneal Curvature, and Corneal Astigmatism in Marfan Syndrome with Ectopia Lentis

Purpose

To investigate the differences in axial length, corneal curvature, and corneal astigmatism with age in patients with Marfan syndrome (MFS) and ectopia lentis.

Methods

A retrospective case series study was conducted. MFS patients with ectopia lentis were divided into groups according to age. Axial length, corneal curvature, and corneal astigmatism were measured.

Results

This study included 114 MFS patients (215 eyes) with a mean age of 19.0 ± 13.9 years. Axial length differed significantly across age groups in MFS patients (P < 0.001), whereas corneal curvature did not (P = 0.767). Corneal astigmatism was statistically significant throughout the MFS cohort (P = 0.009), but no significant difference was found in young MFS patients (P = 0.838). With increasing age, the orientation of the corneal astigmatism changed from with-the-rule astigmatism to against-the-rule or oblique astigmatism (P < 0.001). A linear correlation analysis showed weak correlations between age and axial length for both eyes and with corneal astigmatism for the left eye, but there was no correlation between age and corneal curvature.

Conclusions

In MFS, axial length varies with age, corneal curvature remains stable, and corneal astigmatism is higher in young patients and tends to shift toward against-the-rule or oblique astigmatism. Therefore, it is important to consider age when diagnosing MFS with ocular biometric data.

Athletes and the Aorta: Normal Adaptations and the Diagnosis and Management of Pathology

OPINION STATEMENT

Over a hundred years ago, physicians first recognized that participation in regular, vigorous training resulted in enlargement of the heart. Since that time, the term "athlete's heart" has entered the medical lexicon as a global expression encompassing the electrical, functional, and morphological adaptations that develop in response to physical training. Exercise-induced adaptations of the aorta, which is also exposed to large hemodynamic stresses during prolonged endurance exercise or resistance training, are less well recognized. Young athletes tend to have slightly larger aortas than their sedentary counterparts; however, this rarely exceeds normal ranges for the general population. A systematic approach is advised when presented with an athlete with aortic enlargement. The size of the aorta needs to be first put in the context of the athlete's age, sex, size, and sporting endeavors; however, even in the largest young athletes, the aortic root rarely exceeds 4 cm in men or 3.4 cm in women. A comprehensive evaluation is advised which includes a detailed family history and a thorough physical examination evaluating for signs of any defined connective tissue disorder associated with aortopathy. Downstream testing is then tailored for the individual and may include further tomographic imaging, opthalmology review, and genetic testing. This should ideally be performed at a specialist center. Management of athletes with an aortopathy includes tailoring athletic activity, medical management with strict impulse control, and, in some cases, prophylactic surgery. The issue of sporting eligibility should be individualized and if disqualification is necessary, this should be undertaken by a sports cardiologist or an expert in aortic disease with experience in dealing with an athletic population.

Economic and care considerations of Marfan syndrome

INTRODUCTION

Marfan syndrome is a rare multisystem disease of the connective tissue, which affects multiple organ systems. advances in healthcare have doubled the life-expectancy of patients over the past three decades. to date, there is no comprehensive review that consolidates economic considerations and care for marfan patients. Areas covered: Present research suggests that there may be a link between treatment pattern, disease progression and economic costs of Marfan syndrome. It indicates that an early detection of the disease and preventive interventions achieve a dual aim. From a patient perspective, it may reduce the amount of emergency surgery or intervention, and inpatient stays. In addition, it slows disease progression, lowers lifestyle restrictions, reduces psychological stress, and improves health-related quality of life. Expert commentary: Early detection and preventive measures are likely to achieve a dual aim by simultaneously containing costs and reducing the number and length of inpatient stays.

Periosteal osteosarcoma and Marfan's syndrome: A case report and literature review

Periosteal osteosarcoma (POS) is a rare primary malignant bone tumor arising from the surface of long bones. In addition, Marfan's syndrome (MFS) is an infrequent hereditary autosomal dominant connective tissue disorder with high penetrance and variable phenotypes, which primarily affects the ocular, skeletal and cardiovascular systems. The present study reported a case of POS and MFS co-occurring in a child. A 6-year-old girl with MFS presented with pain, swelling and deformity in the right thigh following a fall. The patient was diagnosed with a right femoral shaft fracture and underwent open internal fixation surgery at a local hospital. At 2 weeks following surgery, the patient's parents observed increased swelling in the right thigh and thus, revisited the clinic. X-ray examination revealed extensive osteotylus around the fracture site and the clinician decided to remove the internal fixation. Following removal of the implant, aggravated swelling and superficial venous engorgement were observed. The patient was then admitted to Nanfang Hospital, where magnetic resonance imaging was performed, which identified symptoms of an abnormal periosteal reaction with bone erosion, indicating POS. The patient underwent a wide resection of the tumor and the histopathological examination confirmed the diagnosis of POS. No recurrence was identified at 9 months postoperatively. In conclusion, the present case report may result in increased awareness of the possibility of malignant bone tumors in a hereditary patient with osteotylus overgrowth following fracture surgery; in addition, the present case indicated a possible correlation between POS and MFS.

Prevalence, incidence, and age at diagnosis in Marfan Syndrome

BACKGROUND

Marfan syndrome is a genetic disorder with considerable morbidity and mortality. Presently, clinicians use the 2010 revised Ghent nosology, which includes optional genetic sequencing of the FBN1 gene, to diagnose patients. So far, only a few studies based on older diagnostic criteria have reported a wide range of prevalence and incidence. Our aim was to study prevalence, incidence, and age at diagnosis in patients with Marfan syndrome.

METHOD

Using unique Danish patient-registries, we identified all possible Marfan syndrome patients recorded by the Danish healthcare system (1977-2014). Following, we confirmed or rejected the diagnosis according to the 2010 revised Ghent nosology.

RESULTS

We identified a total of 1628 persons with possible Marfan syndrome. We confirmed the diagnosis in 412, whereof 46 were deceased, yielding a maximum prevalence of 6.5/100,000 at the end of 2014. The annual median incidence was 0.19/100,000 (range: 0.0-0.7) which increased significantly with an incidence rate ratio of 1.03 (95% CI: 1.02-1.04, p < 0.001). We found a median age at diagnose of 19.0 years (range: 0.0-74). The age at diagnosis increased during the study period, uninfluenced by the changes in diagnostic criteria. We found no gender differences.

CONCLUSION

The increasing prevalence of Marfan syndrome during the study period is possibly due to build-up of a registry. Since early diagnosis is essential in preventing aortic events, diagnosing Marfan syndrome remains a task for both pediatricians and physicians caring for adults.

Perspectives on the revised Ghent criteria for the diagnosis of Marfan syndrome

Three international nosologies have been proposed for the diagnosis of Marfan syndrome (MFS): the Berlin nosology in 1988; the Ghent nosology in 1996 (Ghent-1); and the revised Ghent nosology in 2010 (Ghent-2). We reviewed the literature and discussed the challenges and concepts of diagnosing MFS in adults. Ghent-1 proposed more stringent clinical criteria, which led to the confirmation of MFS in only 32%–53% of patients formerly diagnosed with MFS according to the Berlin nosology. Conversely, both the Ghent-1 and Ghent-2 nosologies diagnosed MFS, and both yielded similar frequencies of MFS in persons with a causative FBN1 mutation (90% for Ghent-1 versus 92% for Ghent-2) and in persons not having a causative FBN1 mutation (15% versus 13%). Quality criteria for diagnostic methods include objectivity, reliability, and validity. However, the nosology-based diagnosis of MFS lacks a diagnostic reference standard and, hence, quality criteria such as sensitivity, specificity, or accuracy cannot be assessed. Medical utility of diagnosis implies congruency with the historical criteria of MFS, as well as with information about the etiology, pathogenesis, diagnostic triggers, prognostic triggers, and potential complications of MFS. In addition, social and psychological utilities of diagnostic criteria include acceptance by patients, patient organizations, clinicians and scientists, practicability, costs, and the reduction of anxiety. Since the utility of a diagnosis or exclusion of MFS is context-dependent, prioritization of utilities is a strategic decision in the process of nosology development. Screening tests for MFS should be used to identify persons with MFS. To confirm the diagnosis of MFS, Ghent-1 and Ghent-2 perform similarly, but Ghent-2 is easier to use. To maximize the utility of the diagnostic criteria of MFS, a fair and transparent process of nosology development is essential.

Difficulties in diagnosing Marfan syndrome using current FBN1 databases

PURPOSE

The diagnostic criteria of Marfan syndrome (MFS) highlight the importance of a FBN1 mutation test in diagnosing MFS. As genetic sequencing becomes better, cheaper, and more accessible, the expected increase in the number of genetic tests will become evident, resulting in numerous genetic variants that need to be evaluated for disease-causing effects based on database information. The aim of this study was to evaluate genetic variants in four databases and review the relevant literature.

METHODS

We assessed background data on 23 common variants registered in ESP6500 and classified as causing MFS in the Human Gene Mutation Database (HGMD). We evaluated data in four variant databases (HGMD, UMD-FBN1, ClinVar, and UniProt) according to the diagnostic criteria for MFS and compared the results with the classification of each variant in the four databases.

RESULTS

None of the 23 variants was clearly associated with MFS, even though all classifications in the databases stated otherwise.

CONCLUSION

A genetic diagnosis of MFS cannot reliably be based on current variant databases because they contain incorrectly interpreted conclusions on variants. Variants must be evaluated by time-consuming review of the background material in the databases and by combining these data with expert knowledge on MFS. This is a major problem because we expect even more genetic test results in the near future as a result of the reduced cost and process time for next-generation sequencing.Genet Med 18 1, 98-102.

Decreased frequency of FBN1 missense variants in Ghent criteria-positive Marfan syndrome and characterization of novel FBN1 variants

The diagnosis of Marfan syndrome (MFS) remains challenging despite the 2010 revision to Ghent nosology criteria, and there is a lack of published information regarding FBN1 genotype associations in patients since the update in Ghent criteria. Applying revised Ghent criteria, we reviewed consecutive proband cases (n=292) submitted for FBN1 sequencing. Testing yielded 207 pathogenic or likely pathogenic FBN1 variants, with 114/207 (55%) missense, 67/207 (32%) non-sense or frameshift, and 28/207 (13%) splicing. There were 130 novel FBN1 variants predicted as pathogenic or likely pathogenic (n=109) or variant of undetermined significance (n=21). Of the 104 patients who met 2010 revised Ghent criteria, 87/104 (82%) had a pathogenic or likely pathogenic variant. There was a significantly lower frequency of missense variants (41 vs 89%; P<0.0001) observed in the Ghent-positive (vs Ghent-negative) patients, and this association held true in age-based groupings. Previously described genotype associations with ectopia lentis and early onset/'neonatal' MFS were confirmed in our cohort. Overall, our study points to the imperfect nature of relying solely on clinical criteria to diagnose MFS as well as the potential importance of truncating/splicing variants in Ghent-positive cases. Furthermore, the description of numerous novel variants and associated clinical findings may be useful for future clinical interpretation of FBN1 genotype in patients with suspected MFS.

Ocular findings in 87 adults with Ghent-1 verified Marfan syndrome

PURPOSE

To study ocular characteristics in 87 patients with verified Marfan syndrome (MFS) based on the Ghent criteria from 1996 (Ghent-1).

METHODS

The position of the lens was noted by observing the eye in different gaze directions in maximal mydriasis during slit lamp examination. Ectopia lentis (EL) was classified as subluxated (dislocation slightly backwards) or luxated (vertical or horizontal displacement). Corneal curvature, axial length (AL), corneal diameter, central corneal thickness, anterior chamber depth, lens thickness, condition of the iris, intraocular pressure, spherical equivalent and visual acuity were also investigated.

RESULTS

EL was found in 108 eyes (62.1%). Of the 68 phakic eyes with EL, 43 (63.2%) had subluxation. Mean AL was 24.80 ± 2.57 mm, and the AL was above 23.5 mm in 65.3%. Mean keratometry (K) in phakic eyes was 41.79 ± 1.70 diopters (D), and the K value was <41.5D in 46.8%. Iris hypoplasia was found in 3.4%. Myopia above 3D occurred in 38.4% of the phakic eyes. Mean binocular logMAR was 0.10 ± 0.32. Only five patients (5.7%) had a logMAR more than 0.5. These 5 patients had EL, and 4 of them were amblyopic.

CONCLUSION

In this strictly defined MFS group fulfilling the Ghent-1 criteria, the prevalence of EL was 62.1%. In many cases, the dislocation of the lens was subtle. On average, the corneas were flattened and the globe length was increased. Only a few patients were visually impaired. Children with MFS should have a thorough follow up to avoid amblyopia.

Personalised External Aortic Root Support (PEARS) Compared with Alternatives for People with Life-Threatening Genetically Determined Aneurysms of the Aortic Root

Personalised external aortic support was first proposed in 2000 by Tal Golesworthy, an engineer with familial Marfan syndrome and an aortic root aneurysm. After putting together a research and development team, and finding a surgeon to take on the challenge to join him in this innovative approach, he was central to the manufacture of the device, custom made for his own aorta. He was the patient for the ‘first in man’ operation in 2004. Ten years later he is well and 45 other people have had their own personalised device implanted. In this account, the stepwise record of proof of principle, comparative quantification of the surgical and perioperative requirements, 10 years of results, and development and research plans for the future are presented.

Bone status in genetic syndromes: a review

More and more data seem to indicate the presence of an increasing number of syndromes and genetic diseases characterized by impaired bone mass and quality. Meanwhile, the improvement of etiopathogenetic knowledge and the employment of more adequate treatments have generated a significant increase in survival related to these syndromes and diseases. It is thus important to identify and treat bone impairment in these patients in order to assure a better quality of life. This review provides an updated overview of bone pathophysiology and characteristics in patients with Down, Turner, Klinefelter, Marfan, Williams, Prader-Willi, Noonan, and 22q11 deletions syndrome. In addition, some options for the treatment of the bone status impairment in these patients will be briefly discussed.

The economic impact of Marfan syndrome: a non-experimental, retrospective, population-based matched cohort study

Background

Marfan syndrome is a rare disease of the connective tissues, affecting multiple organ systems. Elevated morbidity and mortality in these patients raises the issue of costs for sickness funds and society. To date, there has been no study analysing the costs of Marfan syndrome from a sickness fund and societal perspective.

Objective

To estimate excess health resource utilisation, direct (non-)medical and indirect costs attributable to Marfan syndrome from a healthcare payer and a societal perspective in Germany in 2008.

Methods

A retrospective matched cohort study design is applied, using claims data. For isolating the causal effect of Marfan syndrome on excess costs, a genetic matching algorithm was used to reduce differences in observable characteristics between Marfan syndrome patients and the control group. 892 patients diagnosed with Marfan syndrome (ICD-10 Q87.4) were matched from a pool of 26,645 control individuals. After matching, we compared health resource utilisation and costs.

Results

From the sickness fund perspective, an average Marfan syndrome patient generates excess annual costs of €2496 compared with a control individual. From the societal perspective, excess annual costs amount to €15,728. For the sickness fund, the strongest cost drivers are inpatient treatment and care by non-physicians. From the sickness fund perspective, the third (25–41 years) and first (0–16 years) age quartiles reveal the greatest surplus in total costs. Marfan syndrome patients have 39% more physician contacts, a 153% longer average length of hospital stay, 119% more inpatient stays, 33% more prescriptions, 236% more medical imaging and 20% higher average prescription costs than control individuals. Depending on the prevalence, the economic impact from the sickness fund perspective ranges between €24.0 million and €61.4 million, whereas the societal economic impact extends from €151.3 million to €386.9 million.

Conclusions

Relative to its low frequency, Marfan syndrome requires high healthcare expenditure. Not only the high costs of Marfan syndrome but also its burden on patients’ lives call for more awareness from policy-makers, physicians and clinical researchers. Consequently, the diagnosis and treatment of Marfan syndrome should begin as soon as possible in order to prevent disease complications, early mortality and substantial healthcare expenditure.

The ever-expanding conundrum of primary osteoporosis: aetiopathogenesis, diagnosis, and treatment

In recent years, as knowledge regarding the etiopathogenetic mechanisms of bone involvement characterizing many diseases has increased and diagnostic techniques evaluating bone health have progressively improved, the problem of low bone mass/quality in children and adolescents has attracted more and more attention, and the body evidence that there are groups of children who may be at risk of osteoporosis has grown. This interest is linked to an increased understanding that a higher peak bone mass (PBM) may be one of the most important determinants affecting the age of onset of osteoporosis in adulthood. This review provides an updated picture of bone pathophysiology and characteristics in children and adolescents with paediatric osteoporosis, taking into account the major causes of primary osteoporosis (PO) and evaluating the major aspects of bone densitometry in these patients. Finally, some options for the treatment of PO will be briefly discussed.

Epidemiological profile of Marfan syndrome in a general population: a national database study

OBJECTIVE

To explore the current epidemiological profile of Marfan syndrome in a general population.

PATIENTS AND METHODS

Patients who had received a diagnosis of Marfan syndrome were identified from the Taiwan National Health Insurance database records from January 1, 2000, through December 31, 2012 (average population size, 22,765,535). Cardiovascular events and interventions were identified by using the respective International Classification of Diseases codes.

RESULTS

We identified 2329 patients (58% men) with Marfan syndrome. The overall prevalence was 10.2 (95% CI, 9.8-10.7) per 100,000 individuals, with peaks at the age of 15 to 19, 10 to 14, and 20 to 24 years. The minimal birth incidence of 23.3 (95% CI, 21.7-23.3) per 100,000 individuals was estimated in those aged 20 to 29 years. The average annual mortality was 0.23% (69 deaths), mostly owing to cardiac causes (including dissection and sudden death in 40 patients, 58%). Aortic dissection occurred in 226 patients (10%; 61% men) at a mean age of 36.6±10.7 years. The probability of freedom from dissection was 99%, 80%, and 66% at the age of 20, 40, and 50 years, respectively. Of the 69 deaths and 226 dissections during the follow-up period, more than half of the cases occurred before the age of 40 years. Cardiovascular intervention was performed in 360 patients, with early mortality being higher in the emergent operation group (8%) than in the elective group (0%).

CONCLUSION

From this national cohort study, the minimal birth incidence was 23.3 per 100,000 individuals, that is, possibly 1 patient with Marfan syndrome per 4286 people. Despite medical advances, aortic dissection still occurs in about one-tenth of the patients and carries a high mortality risk. Early diagnosis and timely medical interventions are warranted.

A descriptive study of ocular characteristics in Marfan syndrome

PURPOSE

To study the ocular characteristics in patients with Marfan syndrome (MFS).

METHODS

One hundred and two eyes of 51 participants with MFS were included in this descriptive study. Ocular characteristics, visual acuity (VA) and biometric values were studied.

RESULTS

The mean patient age was 39.0 years (range, 12.7-71.6). Seventy-seven eyes were phakic, five aphakic and 20 pseudophakic. Thirty-one eyes had ectopia lentis (EL), 12 eyes cataract, nine eyes strabismus, five eyes glaucoma and four eyes had undergone surgery for a retinal detachment (RD). Ninety-four eyes (92%) had a best spectacle-corrected VA of 0.3 logarithm of the minimum angle of resolution (logMAR) or better. In the 77 phakic eyes, myopia exceeding -3 D was seen in 12/31 eyes (39%) with EL, and in 12/46 eyes (26%) without EL. The mean axial length (AL) was 24.73 mm (range, 21.59-32.75); 39 eyes (51%) had abnormally increased AL (≥24.5 mm). The mean Kmed (mean value of Kmin and Kmax ) was 42.2 D (38.7-46.9 D). No significant difference was found in refraction, AL or corneal curvature between eyes with and without EL. Lens-related astigmatism was seen in 15 (48%) eyes with EL versus four (12%) eyes without EL. Seventeen of the pseudophakic eyes underwent surgery for EL, with history of postoperative RD in one eye.

CONCLUSION

Despite increased AL, high myopia is not as common in MFS as expected because of a flat cornea. Biometry should be considered in suspected cases of MFS when EL is not present.

The c.7409G>A (p.Cys2470Tyr) Variant of FBN1: Phenotypic Variability across Three Generations

Marfan syndrome is an autosomal dominant connective tissue disorder caused by mutations in the fibrillin gene FBN1, which encodes an extracellular matrix glycoprotein. Major features of Marfan syndrome occur in the ocular, cardiovascular, and skeletal systems as well as in the dura mater. Approximately 60% of known disease-causing mutations are missense mutations of single amino acid residues. Effects on the cardiovascular system are classically associated with mutations in exons 24-32 of the 65 FBN1 exons and many, though not all, reports associate missense mutations in exons 59-65 with a mild cardiovascular phenotype. Here we present 5 related individuals among whom a c.7409G>A (p.Cys2470Tyr) missense variant in exon 59 of FBN1 is associated with significant cardiovascular features. The index case also had an apparently de novo 46,XX,del(5)(q33.1q33.3) deletion on chromosome 5. This family demonstrates skeletal, dermatological and neurological features consistent with Marfan syndrome but lacks significant ophthalmological findings to date. These findings suggest that FBN1 C-terminal missense mutations may not confer the ophthalmological features of Marfan syndrome, but they also confer a more significant risk for cardiovascular pathology than that suggested by previous studies. Furthermore, clinical data from this family supports the previously reported association of dural ectasia with C-terminal mutations.

Assessment of bone mineral status in children with Marfan syndrome

Marfan syndrome (MFS) is an autosomal dominant connective tissue disorder with skeletal involvement. It is caused by mutations in fibrillin1 (FBN1) gene resulting in activation of TGF-β, which developmentally regulates bone mass and matrix properties. There is no consensus regarding bone mineralization in children with MFS. Using dual-energy X-ray absorptiometry (DXA), we evaluated bone mineralization in 20 children with MFS unselected for bone problems. z-Scores were calculated based on age, gender, height, and ethnicity matched controls. Mean whole body bone mineral content (BMC) z-score was 0.26 ± 1.42 (P = 0.41). Mean bone mineral density (BMD) z-score for whole body was −0.34 ± 1.4 (P = 0.29) and lumbar spine was reduced at −0.55 ± 1.34 (P = 0.017). On further adjusting for stature, which is usually higher in MFS, mean BMC z-score was reduced at −0.677 ± 1.37 (P = 0.04), mean BMD z-score for whole body was −0.82 ± 1.55 (P = 0.002) and for lumbar spine was −0.83 ± 1.32 (P = 0.001). An increased risk of osteoporosis in MFS is controversial. DXA has limitations in large skeletons because it tends to overestimate BMD and BMC. By adjusting results for height, age, gender, and ethnicity, we found that MFS patients have significantly lower BMC and BMD in whole body and lumbar spine. Evaluation of diet, exercise, vitamin D status, and bone turnover markers will help gain insight into pathogenesis of the reduced bone mass. Further, larger longitudinal studies are required to evaluate the natural history, incidence of fractures, and effects of pharmacological therapy. © 2012 Wiley Periodicals, Inc.

Estimate of de novo mutation frequency in probands with PTEN hamartoma tumor syndrome

PURPOSE

PTEN hamartoma tumor syndrome is an autosomal dominant disorder with increased risks of neoplasias, macrocephaly, and developmental disabilities. While both familial and sporadic cases exist, actual de novo mutation frequency remains unknown. We sought to estimate this within our PTEN-mutation positive patient series.

METHODS

Patients were prospectively accrued if they had known pathogenic germline PTEN mutations or phenotypic features suspicious for PHTS. Only families with pathogenic PTEN mutations were included. Likelihood for de novo mutation was graded from 1 (confirmed inherited) to 5 (confirmed de novo) based on family history and mutation status. Fisher's two-tailed exact and unpaired t-tests were used to compare between groups.

RESULTS

187 pathogenic PTEN-mutation positive families were eligible for this study. De novo (grade 5) status was confirmed in 20 (10.7%) probands, and in 36 (19.3%) was suspected based on family history. Demographics, mutations, and phenotypes were similar for probands graded 1 vs. 5 (all P > 0.06). In grade 1 probands, mutations were inherited equally from maternal and paternal lineages (P = 0.55).

CONCLUSIONS

The frequency of de novo PTEN mutation is at minimum 10.7% and at best 47.6%. Absence of PHTS features within a family history should not preclude consideration of this diagnosis for patients with relevant personal history.

Diagnostic yield in adults screened at the Marfan outpatient clinic using the 1996 and 2010 Ghent nosologies

Marfan syndrome (MFS) is diagnosed according to the Ghent nosology, which has recently been revised. In the Netherlands, evaluation for possible MFS is performed in specialized Marfan outpatient clinics. We investigated the diagnostic yield in our clinic and the impact of the 2010 nosology. All adult patients (n = 343) who visited our clinic between 1998 and 2008 were included. We analyzed their reasons for referral, characteristics, and established diagnoses. In addition, we applied the 2010 nosology to all patients and compared the outcomes to those obtained with the 1996 nosology. Diagnoses that were made using the 1996 and the 2010 Ghent nosology included MFS (44/343 vs. 47/343), familial thoracic aortic aneurysm and/or dissection (22/343 vs. 22/343 patients), Loeys-Dietz syndrome (4/343 vs. 4/343 patients), and (familial) mitral valve prolapse (MVPS; 5/343 vs. 28/343 patients). In both nosologies, 77% of MFS patients had an FBN1 mutation. The 2010 nosology led to an increase in the number of diagnoses made: 4 additional cases of MFS were identified (one patient was "lost" who no longer fulfilled the criteria) and 23 additional cases of MVPS were diagnosed. The diagnostic yield of patients with aortic root dilatation was 65% using the 1996 nosology and 70% using the 2010 nosology. The change in diagnoses did not lead to a difference in clinical follow-up. We conclude that the diagnostic yield of our specialized clinic was high, in particular in patients with aortic root dilatation. Further more the 2010 Ghent nosology led to a significant increase in the number of diagnoses made, mainly due to lowering of the diagnostic threshold for MVPS.

Simultaneous extrusion and intrusion of a scleral buckle in a patient with Marfan's syndrome

An Asian male in his late 50s with known Marfan's syndrome (MFS) presented with sudden deterioration in vision and loss of globe structure 13 years after the placement of a silicone scleral encircling band for the management of retinal detachment. Surgical exploration revealed simultaneous intrusion and extrusion of the encircling band resulting in globe perforation and collapse. This was managed by removal of the encircling band and a scleral patch graft over the defect. This case highlights that in patients with thin sclera, such as in MFS, scleral perforation is a potential complication that should be considered in patients undergoing scleral buckling. Management of this complication is also technically difficult because of impaired healing of the sclera in these patients.

A new mouse model for marfan syndrome presents phenotypic variability associated with the genetic background and overall levels of Fbn1 expression

Marfan syndrome is an autosomal dominant disease of connective tissue caused by mutations in the fibrillin-1 encoding gene FBN1. Patients present cardiovascular, ocular and skeletal manifestations, and although being fully penetrant, MFS is characterized by a wide clinical variability both within and between families. Here we describe a new mouse model of MFS that recapitulates the clinical heterogeneity of the syndrome in humans. Heterozygotes for the mutant Fbn1 allele mgΔ^loxPneo, carrying the same internal deletion of exons 19–24 as the mgΔ mouse model, present defective microfibrillar deposition, emphysema, deterioration of aortic wall and kyphosis. However, the onset of a clinical phenotypes is earlier in the 129/Sv than in C57BL/6 background, indicating the existence of genetic modifiers of MFS between these two mouse strains. In addition, we characterized a wide clinical variability within the 129/Sv congenic heterozygotes, suggesting involvement of epigenetic factors in disease severity. Finally, we show a strong negative correlation between overall levels of Fbn1 expression and the severity of the phenotypes, corroborating the suggested protective role of normal fibrillin-1 in MFS pathogenesis, and supporting the development of therapies based on increasing Fbn1 expression.

Frequency and age-related course of mitral valve dysfunction in the Marfan syndrome

Mitral valve (MV) prolapse (MVP) has a high prevalence of 2% to 3% in the general population and thus constitutes the most common cause of severe nonischemic MV regurgitation (MVR). MVP is also common in persons with the Marfan syndrome. However, to date, a large-scale population-based cohort study using modern echocardiographic techniques has not been performed, and the frequency of MVP and the relation of MV dysfunction and age have not been investigated. Therefore, we conducted a population-based cohort study of 204 patients (108 males and 96 females, aged 31.2 ± 16.4 years) with classic Marfan syndrome. We performed echocardiographic follow-up of 174 patients for a mean of 4.4 ± 4.3 years. On the initial or subsequent echocardiographic scan, MVP was present in 82 patients (40%), severe MVR in 25 (12%), and MV endocarditis in 5 patients (2.5%). At 30 years of age, the Weibull cumulative distribution was 42.6% (95% confidence interval [CI] 36% to 50%) for MVP, 56.5% (95% CI 49.3% to 64%) for MVR of any degree, 6.7% (95% CI 3.9% to 11.3%) for severe MVR, and 0.92% (95% CI 0.21% to 3.91%) for MV endocarditis. The cumulative hazard for severe MVR and MV endocarditis was estimated to increase with age. MVP was associated with dural ectasia (p = 0.01), ectopia lentis (p = 0.02), and skeletal involvement (p <0.001). Severe MVR was related to tricuspid valve prolapse (p = 0.002) and to the sporadic form of the Marfan syndrome (p = 0.006). In conclusion, MVP was comparatively frequent in patients with the Marfan syndrome and carries an increased risk of progression to severe MVR and endocarditis, especially in older adults.

Marfan syndrome

Marfan syndrome is a variable autosomal dominant disorder; most cases result from mutations of fibrillin-1. Diagnosis is guided by the Ghent nosology. The condition may manifest in the cardiovascular and ocular systems. Musculoskeletal manifestations include scoliosis, dural ectasia, protrusio acetabuli, and ligamentous laxity. Compared with patients with idiopathic scoliosis, patients with Marfan syndrome tend to have scoliosis that progresses at a faster rate and is more resistant to bracing; undergo scoliosis surgery complicated by greater blood loss, pseudarthrosis, and additional curvature; and have more frequent occurrences of dural ectasia, which may cause headaches, leg pain, or perineal pain. Protrusio acetabuli may result in hip joint arthritis and may require valgus osteotomy or total hip arthroplasty.

Prevalence data on all Ghent features in a cross-sectional study of 87 adults with proven Marfan syndrome

The prevalence of each single feature in the Ghent criteria in patients with Marfan syndrome (MFS) is not known. To elucidate this, a cross-sectional study of 105 adults with presumed MFS was carried out. All patients were examined by the same group of investigators with standardized and complete assessment of all features in the Ghent criteria. Eighty-seven (83%) fulfilled the criteria in 56 different variants. The most prevalent major criterion in Ghent-positive persons was dural ectasia (91%), followed by major genetic criterion (89%) and ectopic lenses (62 %). In 14 persons (16%), the diagnosis was dependent on the dural findings. In all, 79% fulfilled both major dural and major genetic (positive family history and/or FBN1 mutation) criteria, suggesting that most patients with MFS might be identified by investigating these criteria. A history or finding of ascending aortic disease was present in 46 patients (53%). This low prevalence might partly reflect a high number of diagnosed patients encompassing the whole spectrum of the syndrome. The study confirms the need to examine for the complete set of features in the Ghent criteria to identify all patients with MFS. The majority of persons with MFS might be identified by the combined assessment of dura mater and family history, supplemented with DNA analysis in family-negative cases. The low prevalence of ascending aortic disease might indicate better future prospects in an adult population than those traditionally considered.

Quadrivalvar replacement in infantile Marfan syndrome

Marfan syndrome (MS) is a connective tissue disease involving the cardiovascular, ocular, and the musculoskeletal systems. MS has variable phenotypic expression and is most often diagnosed in adult life. Infantile-onset MS is rare and is associated with severe cardiovascular manifestations; there is an extremely high mortality during the first 2 years of life. We present a case of a child with severe infantile MS who, during the course of infancy and early childhood, developed aortic root dilatation and polyvalvar insufficiency requiring subsequent successful replacement of the aortic root and of all cardiac valves. To our knowledge, this is the first reported case of quadrivalvar replacement in the pediatric age group.

Familial neonatal Marfan syndrome due to parental mosaicism of a missense mutation in the FBN1 gene

We present a family in which three siblings were born with neonatal Marfan syndrome (MFS) to unaffected parents. The clinical findings included joint contractures, large ears, loose skin, ectopia lentis, muscular hypoplasia, aortic root dilatation, mitral and tricuspid valve insufficiency, and pulmonary emphysema. All three siblings died due to cardiorespiratory insufficiency by 2-4 months of age. Screening of the FBN1 gene showed the heterozygous c.3257G > A (p.Cys1086Tyr) mutation in the proband. Mosaicism of the mutation was demonstrated in the somatic cells and in the germ line of the father. Although three examples of parental mosaicism for classical MFS were demonstrated previously, this is the first report of familial occurrence of neonatal MFS due to a heterozygous mutation in FBN1. In conclusion, the p.Cys1086Tyr mutation in FBN1 is consistently associated with neonatal MFS. Parental mosaicism should always be kept in mind when counseling families with MFS.

Current concepts of ocular manifestations in Marfan syndrome

Marfan syndrome is a widespread disorder of connective tissue. It is characterized by systemic and ocular features due to mutations in the fibrillin gene. Awareness and prompt recognition of the ocular complications of Marfan syndrome may enable improvement and preservation of sight. Studies have been performed in the last few years that enable a better understanding of the genetics of the syndrome, earlier diagnosis, and improvement in the surgical techniques and options.

Increased risk of migraine in Marfan's syndrome?

OBJECTIVE

To study the prevalence of migraine in Marfan's syndrome.

MATERIAL AND METHODS

Patients were recruited from Landsforeningen (a patient organization) for Marfan's syndrome. A total of 46 persons were eligible for a validated semi-structured telephone interview by a physician trained in headache diagnostics.

RESULTS

The prevalence of migraine without aura was 13% among men and 40% among women. The prevalence of migraine with aura was 44% among men and 37% among women. The overall prevalence of migraine was 63% with an equal sex ratio. This corresponds to a 3.6- and 2.0-fold significant increased risk among men and women, respectively, compared with the general population.

CONCLUSION

The high prevalence and equal sex ratio of migraine is puzzling and likely to be secondary to Marfan's syndrome. It might be associated with dural ectasia, as the prevalence of dural ectasia is similar to that of migraine in Marfan's syndrome.

Gene expression in acute Stanford type A dissection: a comparative microarray study

Background

We compared gene expression profiles in acutely dissected aorta with those in normal control aorta.

Materials and methods

Ascending aorta specimen from patients with an acute Stanford A-dissection were taken during surgery and compared with those from normal ascending aorta from multiorgan donors using the BD Atlas™ Human1.2 Array I, BD Atlas™ Human Cardiovascular Array and the Affymetrix HG-U133A GeneChip^®. For analysis only genes with strong signals of more than 70 percent of the mean signal of all spots on the array were accepted as being expressed. Quantitative real-time polymerase chain reaction (RT-PCR) was used to confirm regulation of expression of a subset of 24 genes known to be involved in aortic structure and function.

Results

According to our definition expression profiling of aorta tissue specimens revealed an expression of 19.1% to 23.5% of the genes listed on the arrays. Of those 15.7% to 28.9% were differently expressed in dissected and control aorta specimens. Several genes that encode for extracellular matrix components such as collagen IV α2 and -α5, collagen VI α3, collagen XIV α1, collagen XVIII α1 and elastin were down-regulated in aortic dissection, whereas levels of matrix metalloproteinases-11, -14 and -19 were increased. Some genes coding for cell to cell adhesion, cell to matrix signaling (e.g., polycystin1 and -2), cytoskeleton, as well as several myofibrillar genes (e.g., α-actinin, tropomyosin, gelsolin) were found to be down-regulated. Not surprisingly, some genes associated with chronic inflammation such as interleukin -2, -6 and -8, were up-regulated in dissection.

Conclusion

Our results demonstrate the complexity of the dissecting process on a molecular level. Genes coding for the integrity and strength of the aortic wall were down-regulated whereas components of inflammatory response were up-regulated. Altered patterns of gene expression indicate a pre-existing structural failure, which is probably a consequence of insufficient remodeling of the aortic wall resulting in further aortic dissection.

Obstetric complications in Marfan syndrome

OBJECTIVE

To investigate the obstetric maternal and neonatal outcome of pregnancy in women with Marfan syndrome.

METHODS

Retrospective observational multi-center study based on congenital heart disease registry.

RESULTS

Sixty-three of the 122 enrolled women with Marfan syndrome had been pregnant 142 times (including 111 pregnancies>20 weeks, 28 (20%) miscarriages and 3 elective abortions). In 40% of all completed pregnancies an obstetric and/ or neonatal complication occurred. The most important complications were an increased percentage of premature deliveries (n=17, 15%) mainly due to preterm premature rupture of membranes and cervical incompetence and a markedly increased combined fetal and neonatal mortality of 7.1%. An obstetric and/or neonatal complication occurred in a similar proportion of pregnancies in women with a diagnosis of Marfan syndrome before pregnancy versus women with a diagnosis of Marfan syndrome after pregnancy (39% vs. 41%, p=0.85, respectively).

CONCLUSION

In addition to cardiovascular complications, pregnancy in women with Marfan syndrome is associated with a high rate of premature deliveries, preterm premature rupture of membranes and increased mortality in the offspring.