Evolving phenotype of Marfan's syndrome

MRI-Derived Dural Sac and Lumbar Vertebrae 3D Volumetry Has Potential for Detection of Marfan Syndrome

PURPOSE

To assess the feasibility and diagnostic accuracy of MRI-derived 3D volumetry of lower lumbar vertebrae and dural sac segments using shape-based machine learning for the detection of Marfan syndrome (MFS) compared with dural sac diameter ratios (the current clinical standard).

MATERIALS AND METHODS

The final study sample was 144 patients being evaluated for MFS from 01/2012 to 12/2016, of whom 81 were non-MFS patients (46 [67%] female, 36 ± 16 years) and 63 were MFS patients (36 [57%] female, 35 ± 11 years) according to the 2010 Revised Ghent Nosology. All patients underwent 1.5T MRI with isotropic 1 × 1 × 1 mm3 3D T2-weighted acquisition of the lumbosacral spine. Segmentation and quantification of vertebral bodies L3-L5 and dural sac segments L3-S1 were performed using a shape-based machine learning algorithm. For comparison with the current clinical standard, anteroposterior diameters of vertebral bodies and dural sac were measured. Ratios between dural sac volume/diameter at the respective level and vertebral body volume/diameter were calculated.

RESULTS

Three-dimensional volumetry revealed larger dural sac volumes (p < 0.001) and volume ratios (p < 0.001) at L3-S1 levels in MFS patients compared with non-MFS patients. For the detection of MFS, 3D volumetry achieved higher AUCs at L3-S1 levels (0.743, 0.752, 0.808, and 0.824) compared with dural sac diameter ratios (0.673, 0.707, 0.791, and 0.848); a significant difference was observed only for L3 (p < 0.001).

CONCLUSION

MRI-derived 3D volumetry of the lumbosacral dural sac and vertebral bodies is a feasible method for quantifying dural ectasia using shape-based machine learning. Non-inferior diagnostic accuracy was observed compared with dural sac diameter ratio (the current clinical standard for MFS detection).

Marfan and Loeys-Dietz aortic phenotype: A potential tool for diagnosis and management

Objective

In heritable aortic diseases, different vascular involvement may occur with potential variable implications in aortic dilation/dissection risk. This study aimed to analyze the aortic anatomy of individuals with Marfan syndrome and Loeys-Dietz syndrome to identify possible morphological differences.

Methods

Computed tomography and magnetic resonance imaging of the thoracoabdominal aorta from the proximal supra-aortic vessels to the femoral bifurcation level of 114 patients with Marfan and Loeys-Dietz syndromes and 20 matched control subjects were examined. Aortic diameters, areas, length, and tortuosity were measured in different aortic segments using specific vessel analysis software.

Results

Patients with Marfan syndrome showed a higher prevalence of ascending aorta and aortic root dilation (P = .011), larger and longer aortic roots (P = .013) with pear-shaped phenotype, larger isthmus/descending aorta diameter ratio (P = .015), and larger suprarenal aorta and iliac arteries. Patients with Loeys-Dietz syndrome showed longer indexed segments and a significantly longer arch (P = .006) with type 2/3 arch prevalence (P = .097). Measurement ratios analysis provided cut-off values (aortic root to ascending aorta length/aortic root diameter, aortic root/sinotubular junction, aortic root/ascending aorta diameter) differentiating patients with Marfan syndrome from patients with Loeys-Dietz syndrome, even in the early stage of the disease.

Conclusions

Both syndromes show peculiar anatomic patterns at different aortic levels irrespective of aortic dilation and disease severity. These features may represent the expression of different genetic mutations on aortic development, with a potential impact on prognosis and possibly contributing to better management of the diseases. The systematic adoption of whole body imaging with magnetic resonance or computed tomography should always be considered, because they allow a complete vascular assessment with practical indicators of differential diagnosis.

Integrated DNA methylation analysis reveals a potential role for PTPRN2 in Marfan syndrome scoliosis

Background

Marfan syndrome (MFS) is a rare genetic disorder caused by mutations in the Fibrillin-1 gene (FBN1) with significant clinical features in the skeletal, cardiopulmonary, and ocular systems. To gain deeper insights into the contribution of epigenetics in the variability of phenotypes observed in MFS, we undertook the first analysis of integrating DNA methylation and gene expression profiles in whole blood from MFS and healthy controls (HCs).

Methods

The Illumina 850K (EPIC) DNA methylation array was used to detect DNA methylation changes on peripheral blood samples of seven patients with MFS and five HCs. Associations between methylation levels and clinical features of MFS were analyzed. Subsequently, we conducted an integrated analysis of the outcomes of the transcriptome data to analyze the correlation between differentially methylated positions (DMPs) and differentially expressed genes (DEGs) and explore the potential role of methylation-regulated DEGs (MeDEGs) in MFS scoliosis. The weighted gene co-expression network analysis was used to find gene modules with the highest correlation coefficient with target MeDEGs to annotate their functions in MFS.

Results

Our study identified 1253 DMPs annotated to 236 genes that were primarily associated with scoliosis, cardiomyopathy, and vital capacity. These conditions are typically associated with reduced lifespan in untreated MFS. We calculated correlations between DMPs and clinical features, such as cobb angle to evaluate scoliosis and FEV1% to assess pulmonary function. Notably, cg20223687 (PTPRN2) exhibited a positive correlation with cobb angle of scoliosis, potentially playing a role in ERKs inactivation.

Conclusions

Taken together, our systems-level approach sheds light on the contribution of epigenetics to MFS and offers a plausible explanation for the complex phenotypes that are linked to reduced lifespan in untreated MFS patients.

A novel de novo intragenic duplication in FBN1 associated with early-onset Marfan syndrome in a 16-month-old: A case report and review of the literature

Marfan syndrome (MFS) is an autosomal dominant connective tissue disorder due to pathogenic variants in Fibrillin-1 (FBN1) affecting nearly one in every 10,000 individuals. We report a 16-month-old female with early-onset MFS heterozygous for an 11.2 kb de novo duplication within the FBN1 gene. Tandem location of the duplication was further confirmed by optical genome mapping in addition to genetic sequencing and chromosomal microarray. This is the third reported case of a large multi-exon duplication in FBN1, and the only one confirmed to be in tandem. As the vast majority of pathogenic variants associated with MFS are point mutations, this expands the landscape of known FBN1 pathogenic variants and supports consistent use of genetic testing strategies that can detect large, indel-type variants.

The Role of Genetic Testing in Children Requiring Surgery for Ectopia Lentis

Non-traumatic ectopia lentis can be isolated or herald an underlying multisystemic disorder. Technological advances have revolutionized genetic testing for many ophthalmic disorders, and this study aims to provide insights into the clinical utility of genetic analysis in paediatric ectopia lentis. Children that underwent lens extraction for ectopia lentis between 2013 and 2017 were identified, and gene panel testing findings and surgical outcomes were collected. Overall, 10/11 cases received a probable molecular diagnosis. Genetic variants were identified in four genes: FBN1 (associated with Marfan syndrome and cardiovascular complications; n = 6), ADAMTSL4 (associated with non-syndromic ectopia lentis; n = 2), LTBP2 (n = 1) and ASPH (n = 1). Parents appeared unaffected in 6/11 cases; the initial presentation of all six of these children was to an ophthalmologist, and only 2/6 had FBN1 variants. Notably, 4/11 cases required surgery before the age of 4 years, and only one of these children carried an FBN1 variant. In summary, in this retrospective cohort study, panel-based genetic testing pointed to a molecular diagnosis in >90% of paediatric ectopia lentis cases requiring surgery. In a subset of study participants, genetic analysis revealed changes in genes that have not been linked to extraocular manifestations and highlighted that extensive systemic investigations were not required in these individuals. We propose the introduction of genetic testing early in the diagnostic pathway in children with ectopia lentis.

Tricuspid valve prolapse as an early predictor for severe phenotype in children with Marfan syndrome

AIM

In Marfan syndrome, various cardiovascular pathologies, such as aortic dilatation and mitral valve pathologies, already occur in childhood and determine course of the disease. This study aimed to establish additional cardiovascular risk markers for severe Marfan phenotypes. We investigated tricuspid valve prolapse (TVP) and its predictive value for outcome of paediatric Marfan disease.

METHODS

In this retrospective, observational cohort study, we identified 130 paediatric Marfan patients (10.7 ± 4.8 years) with FBN1 variants. We divided patients into two groups based on TVP presence and performed a cross-sectional analysis to investigate the association of TVP with other cardiovascular, ocular and systemic pathologies, at first and last visit. A longitudinal analysis was performed with follow-up data.

RESULTS

At baseline, patients with TVP had higher incidence of aortic root dilatation (p = 0.013), mitral valve prolapse (p = 0.0001) and systemic manifestations (p = 0.025) than patients without TVP. At follow-up, previous presence of TVP predicted higher probability of aortic root dilatation (p = 0.002), mitral valve prolapse (p = 0.0001) and systemic manifestations (p = 0.002).

CONCLUSION

This shows that TVP is linked to both cardiac and extracardiac Marfan manifestations and TVP is an important marker for a disease severity in these children. Therefore, TVP should be assessed routinely using echocardiography in paediatric Marfan patients.

Comparison of Evolution of Aortic Root Dilation and Ghent Criteria in Preadolescents and Adolescents with and without Marfan Syndrome

OBJECTIVE

To determine whether the Ghent Criteria (2010) can be reliably used in evaluating preadolescents and adolescents for Marfan syndrome by comparing aortic growth, systemic scores, and anthropometric features in individuals with and without Marfan syndrome.

STUDY DESIGN

A retrospective chart review was completed for patients less than 15 years of age referred for Marfan syndrome. Comparisons were made between the first and last visit. Paired t tests were used to compare Ghent systemic scores. Wilcoxon rank-sum test were used to compare age, aortic root z scores, height z scores, and body mass index z scores. Recursive partitioning was used to identify combinations of factors to distinguish Marfan syndrome.

RESULTS

In total, 53 individuals met inclusion criteria (29 Marfan syndrome and 24 non-Marfan syndrome). Ghent systemic score increased in the Marfan syndrome group and declined in the non-Marfan syndrome. The non-Marfan syndrome group did not develop progressive aortic root dilation with age. Individuals with Marfan syndrome had higher median height z scores than non-Marfan syndrome, with no difference in median body mass index z score between groups. A combination of aortic root z score above 0.95 and Ghent systemic score above 3 was highly indicative of a Marfan syndrome diagnosis in children less than 15 years of age.

CONCLUSION

The Ghent criteria (2010) can be used to reliably exclude a diagnosis of Marfan syndrome in individuals less than 15 years of age. Genetic testing should be used as an aide in confirming or excluding the diagnosis of Marfan syndrome in individuals with an aortic root z score above 0.95 in combination with a Ghent systemic score above 3 at initial visit.

Differences in Cardiovascular Manifestation of Marfan Syndrome Between Children and Adults

Marfan syndrome (MFS) is a connective tissue disorder characterized by a broad range of clinical manifestations. Cardiovascular involvement is the most life-threatening aspect of the syndrome. Although abnormalities within the cardiovascular system in adults are well documented, there is still a paucity of data regarding manifestation of MFS in childhood. The aim of the study was to compare cardiovascular manifestation of MFS between children and adults. The study population consisted of 236 patients (144 children and 92 adults), who were referred to our department with suspicion of MFS. All patients underwent complete clinical evaluation in order to confirm the diagnosis of MFS according to the modified Ghent criteria. MFS was diagnosed in 101 (44 children and 57 adults) out of the 236 patients. The other patients were diagnosed with Ehlers-Danlos syndrome, Loeys-Dietz syndrome, MASS phenotype, ectopia lentis syndrome, marfanoid habitus and other rare syndromes. The most common cardiovascular abnormality was aortic root dilatation (81.19% of patients). It was found that both adults and children had similar high rates of aortic root dilatation. Similarly, there was no significant difference with regard to the prevalence of aortic valve regurgitation and mitral valve prolapse among children and adults. These findings equivocally indicate that the aforementioned abnormalities develop in early childhood, therefore, they may be used in the early identification of patients with MFS. Other assessed abnormalities, which included mitral valve regurgitation, pulmonary artery dilation, aneurysms of aortic arch, descending thoracic aorta and abdominal aorta were found mostly in adults, and thus, are of less use in the early detection of MFS.

Ten-year reinvestigation of ocular manifestations in Marfan syndrome

IMPORTANCE

Long-term follow-up of Marfan syndrome (MFS) patients.

BACKGROUND

Investigate changes in ocular features in MFS patients fulfilling the Ghent-2 criteria following a period of 10 years.

DESIGN

Repeated cross-sectional study with two observations.

PARTICIPANTS

Eighty-four MFS patients were investigated in 2003-2004 (baseline). Forty-four of these patients (52%) were examined after 10 years.

METHODS

A comprehensive ocular examination performed at baseline and follow-up.

MAIN OUTCOME MEASURES

Development or progression of ectopia lentis (EL).

RESULTS

At follow-up, mean age was 50.1 ± 11.9 years (range: 30-80 years), 74% were female and 70% of the patients were diagnosed with EL compared to 66% at baseline. Two patients (3 eyes) had developed EL over the decade, representing a 13% risk. Furthermore, one eye had progressed from a subtle tilt of the lens to dislocation. We found no significant change in the axial length (P = 0.96), the corneal curvature (P = 0.64) or the spherical equivalent (P = 0.23). Best corrected visual acuity was improved at follow-up (P = 0.02). There were 7% and 33% risks for development of retinal detachment and cataract between baseline and follow-up, respectively.

CONCLUSIONS AND RELEVANCE

Our study indicates that even though EL typically occurs at an early stage in most MFS patients, there is still a risk of developing EL in adulthood. The risk of developing vision-threatening complications such as retinal detachment and cataract was much higher than in the normal population, but even so, the visual potential of the MFS patients was relatively good.

Anomalous Coronary Artery Origin in a Young Patient with Marfan Syndrome

Marfan syndrome is an autosomal dominant genetic disorder that affects connective tissue and is caused by mutations in the fibrillin 1 gene present at chromosome 15. Aortic aneurysm is its main complication, and along the dilation of the aorta root and its descending portion (60–100%), with secondary aortic insufficiency, it increases risk of acute aortic dissection and death. Coronary artery anomalies affect between 0.3% and 1.6% of the general population and are the second leading cause of sudden death in young adults, especially if the anomalous coronary passes through aorta and pulmonary artery. The anomalous origin of the left main coronary artery in the right Valsalva sinus has a prevalence of 0.02%–0.05% and is commonly related to other congenital cardiac anomalies, such as transposition of great vessels, coronary fistulas, bicuspid aortic valve, and tetralogy of Fallot. Its association with Marfan syndrome is not known, and there is no previous report in the literature. We describe here a case of a female with Marfan syndrome diagnosed with symptomatic anomalous origin of the left coronary artery in the right Valsalva sinus.

The importance of genotype-phenotype correlation in the clinical management of Marfan syndrome

Background

Marfan syndrome (MFS) is a disorder of autosomal dominant inheritance, in which aortic root dilation is the main cause of morbidity and mortality. Fibrillin-1 (FBN-1) gene mutations are found in more than 90% of MFS cases. The aim of our study was to summarise variants in FBN-1 and establish the genotype-phenotype correlation, with particular interest in the onset of aortic events, in a broad population of patients with an initial clinical suspicion of MFS.

Material and methods

This single centre prospective cohort study included all patients presenting variants in the FBN-1 gene who visited a Hereditary Aortopathy clinic between September 2010 and October 2016.

Results

The study included 90 patients with FBN-1 variants corresponding to 58 non-interrelated families. Of the 57 FBN-1 variants found, 25 (43.9%) had previously been described, 23 of which had been identified as associated with MFS, while the the remainder are described for the first time. For 84 patients (93.3%), it was possible to give a definite diagnosis of Marfan syndrome in accordance with Ghent criteria. 44 of them had missense mutations, 6 of whom had suffered an aortic event (with either prophylactic surgery for aneurysm or dissection), whereas 20 of the 35 patients with truncating mutations had suffered an event (13.6% vs. 57.1%, p < 0.001). These events tended to occur at earlier ages in patients with truncating compared to those with missense mutations, although not significantly (41.33 ± 3.77 vs. 37.5 ± 9.62 years, p = 0.162).

Conclusions

Patients with MFS and truncating variants in FBN-1 presented a higher proportion of aortic events, compared to a more benign course in patients with missense mutations. Genetic findings could, therefore, have importance not only in the diagnosis, but also in risk stratification and clinical management of patients with suspected MFS.

Electronic supplementary material

The online version of this article (10.1186/s13023-017-0754-6) contains supplementary material, which is available to authorized users.

Skeletal evolution in Marfan syndrome: growth curves from a French national cohort

BackgroundTo describe the growth patterns of children affected by Marfan syndrome (MFS) compared with those of unaffected children and to create growth charts.MethodsAn observational study of children referred to the French National MFS Reference Centre. A total of 259 children carrying an FBN1 gene mutation and fulfilling Ghent 1 criteria (MFS group) and 474 mutation-negative sibling controls (non-MFS group) were evaluated. Both groups were compared with French-accepted reference nomograms (Reference group).ResultsBoys and girls from the MFS group were significantly taller than those in the non-MFS group and in the reference group at all ages (P<0.0001). But, MFS children's overgrowth reduced with age. At 17 years of age, the mean height (MFS vs. non-MFS) was 191.2±8.4 cm (+2.9 SD) vs. 182.9±8.1 (+1.6 SD) for boys and 178.3±7.6 cm (+2.7 SD) vs. 169.5±6.8 (+1.2 SD) for girls, respectively. By contrast, the mean BMI of children in the MFS group was similar to those in the non-MFS group and inferior to the values of French general population, evolving around -1 SD.ConclusionGrowth patterns differ in patients with an FBN1 mutation. Knowing the growth parameters should allow physicians to better counsel patients and detect the associated diseases. The provided curves could also help to predict the final height.

Exome sequencing identifies de novo pathogenic variants in FBN1 and TRPS1 in a patient with a complex connective tissue phenotype

Here we describe a patient who presented with a history of congenital diaphragmatic hernia, inguinal hernia, and recurrent umbilical hernia. She also has joint laxity, hypotonia, and dysmorphic features. A unifying diagnosis was not identified based on her clinical phenotype. As part of her evaluation through the Undiagnosed Diseases Network, trio whole-exome sequencing was performed. Pathogenic variants in FBN1 and TRPS1 were identified as causing two distinct autosomal dominant conditions, each with de novo inheritance. Fibrillin 1 (FBN1) mutations are associated with Marfan syndrome and a spectrum of similar phenotypes. TRPS1 mutations are associated with trichorhinophalangeal syndrome types I and III. Features of both conditions are evident in the patient reported here. Discrepant features of the conditions (e.g., stature) and the young age of the patient may have made a clinical diagnosis more difficult in the absence of exome-wide genetic testing.

Clinical Stratification of Pediatric Patients with Idiopathic Thoracic Aortic Aneurysm

OBJECTIVES

To describe the global phenotypes of pediatric patients with thoracic aortic aneurysm (TAA) who do not have a clinical diagnosis of Marfan syndrome (MFS) or related connective tissue disorders. We hypothesized that the presence of noncardiovascular abnormalities correlate with TAA severity and that medical therapy reduces TAA progression.

STUDY DESIGN

This is a retrospective case series of patients with TAA age ≤ 21 years evaluated in a cardiovascular genetics clinic. Patients meeting clinical criteria for MFS or related disorders were excluded. Repeated measures analyses of longitudinal echocardiographic measurements of the aorta were used to test associations between TAA severity and noncardiovascular phenotype and to assess the impact of medical therapy.

RESULTS

Sixty-nine patients with TAA at mean age 12.5 ± 5.3 years were included. Noncardiovascular abnormalities, including skeletal (65%) or craniofacial (54%) findings, were frequently observed. Increased rate of aortic root enlargement was associated with ocular (P = .002) and cutaneous (P = .003) abnormalities, and increased rate of ascending aorta enlargement was associated with craniofacial (P < .001) abnormalities. Beta blocker or angiotensin receptor blocker therapy (n = 41) was associated with reduction in the rate of aortic root growth (P = .018).

CONCLUSIONS

Children with TAA not satisfying diagnostic criteria for MFS or related disorders frequently have noncardiovascular findings, some of which are associated with TAA progression. Because therapy initiation may reduce risk of progression and long-term complications, comprehensive assessment of noncardiovascular findings may facilitate early risk stratification and improve outcomes.

Areal bone mineral density in children and adolescents with Marfan syndrome: evidence of an evolving problem

Marfan syndrome (MFS), an autosomal dominant disorder of connective tissue, is due to defective fibrillin-1. Defects involve the cardiovascular system, the eye, the lungs, and the skeleton. The aim of the current study was to characterize the bone mineral status in children and adolescents with MFS. We performed an observational cross-sectional study and a longitudinal follow-up of two years. We enrolled 73 young patients with MFS (3-17years). A subset of 44 patients participated in the longitudinal study. Healthy children were studied as controls for biochemical analyses. Bone mineral density (BMD) was measured at lumbar spine, femoral neck and total femur by dual-energy X-ray absorptiometry. BMD values were expressed as Z-scores adjusted for height using height-for-age Z-scores. BMD measurements corrected for height were significantly lower than reference at all skeletal sites (P<0.0001). Patient on cardiac treatment with losartan had lower BMD measurements corrected for height compared to non-treated patients. Total femur BMD decreased significantly over time (P=0.027). BMD at the other two skeletal sites did not change significantly during follow-up, but remained significantly low compared to reference (P<0.0001). In conclusion, young patients with MFS have markedly low BMD at the lumbar spine and femur, and values show a tendency to decrease over time in the peripheral skeleton. Because increased life expectancy of MFS patients, the reduced BMD during childhood may lead to a low peak bone mass, increasing the fracture risk during adult life.

Kid-Short Marfan Score (Kid-SMS) Is a Useful Diagnostic Tool for Stratifying the Pre-Test Probability of Marfan Syndrome in Childhood

Due to age dependent organ manifestation, diagnosis of Marfan syndrome (MFS) is a challenge, especially in childhood. It is important to identify children at risk of MFS as soon as possible to direct those to appropriate treatment but also to avoid stigmatization due to false diagnosis. We published the Kid-Short Marfan Score (Kid-SMS) in 2012 to stratify the pre-test probability of MFS in childhood. Hence we now evaluate the predictive performance of Kid-SMS in a new cohort of children. We prospectively investigated 106 patients who were suspected of having MFS. At baseline, children were examined according to Kid-SMS. At baseline and follow-up visit, diagnosis of MFS was established or rejected using standard current diagnostic criteria according to the revised Ghent Criteria (Ghent-2). At baseline 43 patients were identified with a risk of MFS according to Kid-SMS whereas 21 patients had Ghent-2 diagnosis of MFS. Sensitivity was 100%, specificity 77%, negative predictive value 100% and Likelihood ratio of Kid-SMS 4.3. During follow-up period, three other patients with a stratified risk for MFS were diagnosed according to Ghent-2. We confirm very good predictive performance of Kid-SMS with excellent sensitivity and negative predictive value but restricted specificity. Kid-SMS avoids stigmatization due to diagnosis of MFS and thus restriction to quality of life. Especially outpatient pediatricians and pediatric cardiologists can use it for primary assessment.

[Clinical signs of Marfan syndrome in children under 10 years of age]

Diagnosing Marfan syndrome in young children is difficult because of the great variability of expression of the disease and because the phenotype evolves over the life course. The goal of this retrospective study was to describe the first clinical symptoms in children under 10 years of age with Marfan syndrome and to evaluate the pertinence of the new 2010 Ghent criteria in comparison with the 1996 criteria. Seventeen patients under 10 by the time of the first medical examination were included. All children had an FBN1 gene mutation that was secondarily demonstrated. Clinical data including ophthalmological, cardiac, and orthopaedic examinations obtained during the first medical examination were analyzed. The most frequent abnormalities encountered were high arched palate (82%), arachnodactyly (71%), and flatfoot (59%). Aortic aneurysm (47%) and ectopic lens (35%) were also seen at the time of diagnosis. According to the 2010 Ghent criteria, the diagnosis of Marfan syndrome could be obtained in 71% of patients after identification of the mutation of the FBN1 gene, whereas only 59% of patients were diagnosed using the older criteria. All organs can be affected during childhood. An early diagnosis is essential in order to set up specific management.

Study of phenotype evolution during childhood in Marfan syndrome to improve clinical recognition

PURPOSE

Because diagnosis of Marfan syndrome is difficult during infancy, we used a large cohort of children to describe the evolution of the Marfan syndrome phenotype with age.

METHODS

Two hundred and fifty-nine children carrying an FBN1 gene mutation and fulfilling Ghent criteria were compared with 474 non-Marfan syndrome children.

RESULTS

Prevalence of skeletal features changed with aging: prevalence of pectus deformity increased from 43% at 0-6 years to 62% at 15-17 years, wrist signs increased from 28 to 67%, and scoliosis increased from 16 to 59%. Hypermobility decreased from 67 to 47% and pes planus decreased from 73 to 65%. Striae increased from 2 to 84%. Prevalence of ectopia lentis remained stable, varying from 66 to 72%, similar to aortic root dilatation (varying from 75 to 80%). Aortic root dilatation remained stable during follow-up in this population receiving β-blocker therapy. When comparing Marfan syndrome children with non-Marfan syndrome children, height appeared to be a simple and discriminant criterion when it was >3.3 SD above the mean. Ectopia lentis and aortic dilatation were both similarly discriminating.

CONCLUSION

Ectopia lentis and aortic dilatation are the best-discriminating features, but height remains a simple discriminating variable for general practitioners when >3.3 SD above the mean. Mean aortic dilatation remains stable in infancy when children receive a β-blocker.

Range of motion of the healthy pediatric elbow: cross-sectional study of a large population

To evaluate normative data on elbow range of motion (ROM) in the pediatric population. The passive ROM of 1361 healthy pediatric elbows was measured using a small goniometer calibrated in 1° increments, and recorded. The mean amount of flexion, extension, and arc of motion was 142°, -11°, and 153°, respectively. Our data indicated no meaningful correlation between patient sex, age, or weight and the amount of flexion, extension, or the total arc of motion. It appears that elbow ROM in this population is not affected by sex, age, or weight. Normative data are critical when setting the goals of a particular therapeutic approach.

The Kid-Short Marfan Score (Kid-SMS) - an easy executable risk score for suspected paediatric patients with Marfan syndrome

AIM

Due to age-dependent manifestations, diagnosis of Marfan syndrome (MFS) in children and adolescents is sophisticated. Although revised Ghent criteria is a major step forward, its utility in children is still restricted due to expensive and technically advanced diagnostics. As early diagnosis submits long-term benefits concerning prognosis, the need of an appropriate diagnostic tool for risk stratification of suspected paediatric patients with Marfan is justified.

METHODS AND RESULTS

Sixty paediatric patients with Marfan were subject to a standardized diagnostic programme. All clinical symptoms of the revised Ghent nosology were analysed concerning age at first clinical manifestation, prevalence and likelihood ratio for MFS. Symptoms with early onset, high prevalence and high positive likelihood ratio were identified and combined for a risk score called Kid-Short Marfan Score (Kid-SMS). Three risk categories for suspicion of Marfan syndrome were developed. Finally, the Kid-SMS was operated in 130 paediatric patients with suspected MFS. Kid-SMS identified significantly more suspected patients with Marfan compared with Ghent nosology, revised Ghent and genetics alone without oversensitivity.

CONCLUSION

Whereas diagnosis of MFS in childhood is sophisticated, Kid-SMS is a useful tool for risk stratification of suspected paediatric patients with Marfan by easy executable diagnostics, especially for paediatricians and paediatric cardiologists.

The diagnostic value of the facial features of Marfan syndrome

PURPOSE

We examined the prevalence of known facial features of Marfan syndrome (MFS)-dolicocephaly, malar hypoplasia, enophthalmos, retrognathia, and down-slanting palpebral fissures-and the diagnostic utility (sensitivity, specificity, accuracy, predictive values, and likelihood ratios) of using them for screening and diagnosis.

METHODS

Frontal and lateral photographs of 76 subjects with MFS (average age 18.3 years) and of 76 age- and gender-matched controls were obtained, randomized, and compiled into an online survey. Three physicians experienced with MFS rated each photograph for the presence of each feature and indicated whether each photograph triggered a suspicion for MFS. Eight non-expert orthopaedic surgeons reviewed a subset of those photographs and indicated if each triggered a suspicion for MFS. Half of the non-experts then received a brief diagnosis instructional sheet, and all non-experts were retested. The results were compared using Chi-square tests and t-tests with a significance level of P < 0.05.

RESULTS

Using facial features alone, the accuracy of experienced physicians in identifying individuals with MFS was 73%. Facial features had a 54% sensitivity, a 91% specificity, an 86% positive predictive value (PPV), a 67% negative predictive value (NPV), a 6.9% positive likelihood ratio (PLR), and a 50% negative likelihood ratio (NLR) for MFS. There was no significant difference in the diagnostic accuracy between non-experts receiving and not receiving instructions.

CONCLUSIONS

Facial features are more specific than sensitive for MFS. Therefore, the recognition of facial features of MFS can be used as an initial screening tool, but facial features do not have a high sensitivity for MFS.

Comparison of clinical characteristics and frequency of adverse outcomes in patients with Marfan syndrome diagnosed in adulthood versus childhood

Patients with Marfan syndrome (MFS) continue to elude diagnosis until well into adulthood. The purpose of this study was to compare the clinical characteristics and outcomes of adult survivors with MFS diagnosed during adulthood (age, >or=18 years) with those of adult survivors with MFS diagnosed in childhood (<18 years). We conducted a retrospective review of 66 adult (age, >18 years) MFS patients seen at a combined pediatric and adult multidisciplinary MFS clinic from 2004 to 2006. Demographic, clinical, and cardiac variables were collected and a comparative analysis was performed between the two groups: patients diagnosed with MFS during childhood and patients diagnosed in adulthood. The primary outcome measures were the presence of aortic dissection and the need for urgent cardiovascular surgery. Despite a similar incidence of clinical characteristics, 39 of the 66 MFS patients were not diagnosed until adulthood. The overall incidence of major cardiac involvement was comparable between the two groups, although the patients diagnosed at a younger age were found to have a reduced need for aortic surgery (33% vs. 59%; P < 0.04) and fewer adverse cardiac outcomes (0% vs. 46%; P < 0.001). Moreover, the patients diagnosed with MFS in adulthood were more likely to require repeated surgical intervention for distal aortic disease (13% vs. 0%; P = 0.07). In conclusion, patients with MFS who remain undiagnosed until adulthood have well-established cardiovascular pathology frequently requiring surgical intervention. Due to this delay in diagnosis and management, they often suffer from a suboptimal clinical outcome. Our research demonstrates the importance of educating pediatric clinicians in early MFS diagnosis in hopes of improving the long-term outcome of all MFS patients.

Clinical and molecular study of 320 children with Marfan syndrome and related type I fibrillinopathies in a series of 1009 probands with pathogenic FBN1 mutations

From a large series of 1009 probands with pathogenic FBN1 mutations, data for 320 patients <18 years of age at the last follow-up evaluation were analyzed (32%). At the time of diagnosis, the median age was 6.5 years. At the last examination, the population was classified as follows: neonatal Marfan syndrome, 14%; severe Marfan syndrome, 19%; classic Marfan syndrome, 32%; probable Marfan syndrome, 35%. Seventy-one percent had ascending aortic dilation, 55% ectopia lentis, and 28% major skeletal system involvement. Even when aortic complications existed in childhood, the rates of aortic surgery and aortic dissection remained low (5% and 1%, respectively). Some diagnostic features (major skeletal system involvement, striae, dural ectasia, and family history) were more frequent in the 10- to <18-year age group, whereas others (ascending aortic dilation and mitral abnormalities) were more frequent in the population with neonatal Marfan syndrome. Only 56% of children could be classified as having Marfan syndrome, according to international criteria, at their last follow-up evaluation when the presence of a FBN1 mutation was not considered as a major feature, with increasing frequency in the older age groups. Eighty-five percent of child probands fulfilled international criteria after molecular studies, which indicates that the discovery of a FBN1 mutation can be a valuable diagnostic aid in uncertain cases. The distributions of mutation types and locations in this pediatric series revealed large proportions of probands carrying mutations located in exons 24 to 32 (33%) and in-frame mutations (75%). Apart from lethal neonatal Marfan syndrome, we confirm that the majority of clinical manifestations of Marfan syndrome increase with age, which emphasizes the poor applicability of the international criteria to this diagnosis in childhood and the need for follow-up monitoring in cases of clinical suspicion of Marfan syndrome.

Ageing in Marfan syndrome

AIMS

Marfan syndrome (MFS) is a dominantly inherited connective tissue disorder caused by mutations in the fibrillin-1 gene. Past research has focused on younger patients as lifespan was known to be significantly reduced. This study aims to describe the complications, including those affecting the eyes, heart and musculoskeletal system, faced by older survivors.

METHODS

All 2500 patient records from the National Marfan Syndrome Clinical Database were searched for suitable participants aged 50 or older. One hundred and fifty-six questionnaires were posted to patients with MFS. These patients were sent a detailed questionnaire regarding medical aspects of their disease. Those included in the study were sent questionnaires for spouses and friends (not blood relatives) to complete, to provide control data. Other age- and sex-matched controls were recruited locally.

RESULTS

Sixty questionnaires from patients with MFS (35%) were returned and eligible for inclusion in the study, comprising 28 female patients and 32 male patients with a median age of 57. We recruited 56 eligible controls. Our results revealed that patients over 50 years of age with MFS may be at a higher risk than previously assumed for retinal detachment (reported by 24% of our respondents) and cardiovascular abnormalities (42% have had past aortic surgery; 53% report palpitation). Lesser known complications were also reported, including cataract (reported by 27%).

CONCLUSIONS

Medical practitioners should be aware of the range of complications that can occur in patients with MFS in addition to the normal ageing process. Health problems in MFS patients over 50 may require investigation and specific therapy earlier than in the normal ageing population, because of the degenerative nature of this genetic condition.

Marfan syndrome: clinical diagnosis and management

Marfan syndrome is a multisystem connective tissue disorder usually associated with mutation in fibrillin, and occasionally with mutation in TGFBR1 or 2. The clinical diagnosis is made using the Ghent nosology, which will unequivocally diagnose or exclude Marfan syndrome in 86% of cases. Use of a care pathway can help implementation of the nosology in the clinic. The penetrance of some features is age dependent, so the nosology must be used with caution in children. Molecular testing may be helpful in this context. The nosology cannot be used in families with isolated aortic dissection, or with related conditions such as Loeys-Dietz syndrome, although it may help identify families for further diagnostic evaluation because they do not fulfill the nosology, despite a history of aneurysm. Prophylactic medical (eg beta-blockade) and surgical intervention is important in reducing the cardiovascular complications of Marfan syndrome. Musculoskeletal symptoms are common, although the pathophysiology is less clear--for example, the correlation between dural ectasia and back pain is uncertain. Symptoms in other systems require specialist review such as ophthalmology assessment of refractive errors and ectopia lentis. Pregnancy is a time of increased cardiovascular risk for women with Marfan syndrome, particularly if the aortic root exceeds 4 cm at the start of pregnancy. High-intensity static exercise should be discouraged although low-moderate intensity dynamic exercise may be beneficial. The diagnosis and management of Marfan syndrome requires a multidisciplinary team approach, in view of its multisystem effects and phenotypic variability.

Marfan's syndrome and the heart

In recent years, there have been many advances in the treatment of cardiac disease in children with Marfan's syndrome. Early diagnosis, meticulous echocardiographic follow-up and multidisciplinary assessment are essential. Medical treatment with beta-blockers is probably helpful in most children with aortic root dilatation. Research on TGFbeta signalling and the potential treatment role of TGFbeta antagonists may lead to exciting new treatments, but the results of clinical trials are awaited. In managing the cardiovascular complications of Marfan's syndrome, the paediatrician has to walk a difficult path. On the one hand, restrictive lifestyle advice and drugs may need to be prescribed, often in the context of a family history of major surgery or even sudden death. On the other hand, it is essential to encourage the often asymptomatic child to develop and mature as normally as possible.

Elbow range of motion and clinical carrying angle in a healthy pediatric population

Many conditions including trauma can affect the range of motion and carrying angle of the elbow in children. The method employed was cross-sectional clinical measurement of 600 elbows (300 patients) range of motion and carrying angle in normal children. We found significant increases in range of motion and carrying angle with age (P<0.01) and significantly increased range of motion and carrying angle in females as compared with males (P<0.01). In conclusion, elbow joint range of motion and carrying angle increase with age. This is the first cross-sectional analysis of range of motion and carrying angle to our knowledge in the pediatric population. Increased elbow extension may contribute to the increased carrying angle seen in females compared with males.

Okuläre Manifestationen und chirurgische Ergebnisse beim Marfan-Syndrom

AIM

This retrospective study should examine and judge the surgical indications and the therapeutic possibilities as well as their complications in patients with ocular manifestations of Marfan syndrome (MFS) diagnosed according to the criteria of the Ghent nosology.

PATIENTS AND METHODS

The study included 17 patients. Operative indications were increasing subluxation of the lens, retinal detachments and secondary glaucoma. The operative procedure depended on patient age and findings. Eleven MFS patients were operated in both eyes and six MFS patients in one eye.

RESULTS

Stabilization or functional improvement of visual acuity could be achieved in all patients in whom no disorders limiting visual acuity or amblyopia were present preoperatively. In six eyes of five patients, lens insertion was accomplished via a pars plana approach. Lens removal without implantation of an intraocular lens was performed in 16 eyes of 10 patients. Pars plana vitrectomy was accomplished in 12 eyes. Complications were well controlled by pars plana vitrectomy.

CONCLUSIONS

Difficult preoperative situations and postoperative complications are not rare in MFS patients. However, they can be controlled well by means of modern vitreous surgery.

Dural ectasia in children with Marfan syndrome: a prospective, multicenter, patient-control study

The clinical diagnosis of Marfan syndrome in childhood is difficult, because symptoms may not have developed to their full expression until adulthood. The Ghent nosology for the diagnosis of Marfan syndrome classifies dural ectasia as a major diagnostic criterion. More than two thirds of adult patients with Marfan syndrome show dural ectasia, while the frequency in childhood is unknown. This prospective multicenter observational patient-control study was performed to identify pathologic changes of the lumbosacral spine in young patients with Marfan syndrome.

DESIGN

Prospective clinical trial, multicentric, cross-sectional.

SETTING

MRI of the lumbosacral spine.

PATIENTS

Twenty patients with proven Marfan syndrome, 20 patients suspicious for Marfan syndrome and 38 healthy controls.

OUTCOME MEASURES

Vertebral body diameter (VBD) from L1 to S1, dural sac diameter (DSD) from L1 to S1, dural sac ratio (DSR), qualitative assessment of the lumbosacral spine.

RESULTS

DSD and VBD in different age groups were higher in patients with proven or suspected Marfan syndrome than in healthy controls (DSD: L1, 6-8 years, P < 0.05). VBD related to body height showed a similar growth related increase in patients with proven or suspected Marfan syndrome and controls. DSD related to body height was elevated in patients with proven or suspected Marfan syndrome at different levels of the lumbar spine. DSD at levels L1, L5, and S1, and DSR at levels L5 and S1 of patients with proven Marfan syndrome were significantly higher (P < 0.05) than in controls.

CONCLUSION

Even during childhood pathologic changes inside the lumbosacral spine of patients with Marfan syndrome can be observed. Dural ectasia, which occurs at different levels of the lumbar spine, can be detected at levels L5 and S1 in up to 40% of patients with Marfan syndrome.

Diagnostic power of aortic elastic properties in young patients with Marfan syndrome

BACKGROUND

In patients with Marfan syndrome, progressive aortic dilation implicates a still-unpredictable risk of life-threatening aortic dissection and rupture. We sought to quantify aortic wall dysfunction noninvasively, determine the diagnostic power of various aortic parameters, and establish a diagnostic model for the early detection of aortic abnormalities associated with Marfan syndrome.

METHODS

In 19 patients with Marfan syndrome (age, 17.7 +/- 9.5 years) and 19 age- and sex-matched healthy control subjects, computerized ascending and abdominal aortic wall contour analysis with continuous determination of aortic diameters was performed out of transthoracic M-mode echocardiographic tracings. After simultaneous oscillometric blood pressure measurement, aortic elastic properties were determined automatically.

RESULTS

The following ascending aortic elastic parameters showed statistically significant differences between the Marfan group and the control group: (1) decreased aortic distensibility ( P < .001), (2) increased wall stiffness index ( P < .01), (3) decreased systolic diameter increase ( P < .01), and (4) decreased maximum systolic area increase ( P < .001). The diagnostic power of all investigated parameters was tested by single logistic regression models. A multiple logistic regression model including solely aortic parameters yielded a sensitivity of 95% and a specificity of 100%.

CONCLUSIONS

In young patients with Marfan syndrome, a computerized image-analyzing technique revealed decreased aortic elastic properties expressed by parameters showing high diagnostic power. A multiple logistic regression model including merely aortic parameters can serve as useful predictor for Marfan syndrome.

Relationship between foot angles and hypermobility scores and assessment of foot types in hypermobile individuals

This study proposed to assess foot types and radiological examination of feet of individuals with hypermobility syndrome in comparison to healthy matched controls for age, sex, and body mass index. The relationship between foot angles and hypermobility scores of subjects in both groups were also~assessed. Twenty individuals having joint hypermobility syndrome previously diagnosed according to Beighton and Bulbena scores were compared to 20 healthy subjects. Standing anteroposterior (AP) and lateral weigthbearing radiographs of feet of the individuals were taken. Foot angles and foot types were evaluated on the AP and lateral views. The mean +/- SD of Beighton and Bulbena scores were significantly higher in the hypermobile individuals (p <.001) than in controls. In both groups, Egyptian and square types of feet were mostly encountered (p >.05). Bilateral calcaneal pitch (CP) angles (p <.001), bilateral talometatarsal (TM) angles (p <.01), and right apex angles (p <.05) were significantly low in hypermobile individuals, whereas first metatarsophalangeal (MTP) angles were significantly high (right foot, p <.01; left foot, p <.05) as compared to the control group. Hypermobility scores correlated negatively with bilateral CP and TM angles and positively with bilateral first MTP angles. No correlation was found for the other~angles. These finding suggest that foot angles (especially CP, TM and first MTP angles) are in relation with severity of hypermobility. There was no difference between foot types in the hypermobile individuals and healthy controls. These angles may be useful for clinically monitoring the foot health in the hypermobile individuals.

Interventional treatment methods in patients with Marfan Syndrome

Marfan syndrome is an autosomal dominant heritable connective tissue disorder which involves primarily the skeletal, ocular and cardiovascular system. The incidence of MS is on average 1: 10000 with 25-30% of cases caused by sporadic mutations.The leading cause of premature death in these patients is progressive dilatation and subsequent dissection of the ascending thoracic aorta resulting in cardiac tamponade, and left ventricular failure due to aortic regurgitation. Life expectancy is primarily determined by the severity of cardiovascular involvement, and has improved substantially over the last 20 years due to the advances in surgical and medical management.The optimum management of Marfan patients includes a lifelong surveillance with particular emphasis placed on aortic behaviour. Preventive replacement of various portions of the aorta has been a major contribution for improved life expectancy in these patients. The different surgical and interventional treatment options currently available will be further outlined in this review.

Identify and manage marfan syndrome in children

Marfan syndrome can reduce life expectancy and quality of life because of cardiac, orthopedic, ocular, and other system impairments. This article describes the syndrome from infancy through adolescence and our role in its identification and management.

Overgrowth

The predominant influences on fetal growth are maternal and placental factors. Post-natal growth is regulated by a complex interaction between genetic, environmental and hormonal influences. The role of the growth hormone insulin-like growth factor (GH-IGF) system is explored, including the emerging role of IGF-2 in fetal growth. Increasing understanding of the genetics of overgrowth and short stature syndromes is contributing greatly to basic understanding of growth regulation. A range of prenatal overgrowth syndromes is discussed, including those associated with neonatal hyperinsulinism and hypoglycaemia.Post-natal overgrowth may be caused by a diverse range of normal variant conditions, endocrine disorders, chromosomal abnormalities and other genetic syndromes. An approach to diagnosis is presented and major conditions discussed in detail. Sex-steroid therapy for height limitation continues to be a controversial area with uncertainty about height prediction, benefits achieved and possible long-term side-effects.

Mutations of FBN1 and genotype-phenotype correlations in Marfan syndrome and related fibrillinopathies

The Marfan syndrome (MFS) is a pleiotropic, autosomal dominant disorder of connective tissue with highly variable clinical manifestations including aortic dilatation and dissection, ectopia lentis, and a series of skeletal anomalies. Mutations in the gene for fibrillin-1 (FBN1) cause MFS, and at least 337 mainly unique mutations have been published to date. FBN1 mutations have been found not only in MFS but also in a range of connective tissue disorders collectively termed fibrillinopathies ranging from mild phenotypes, such as isolated ectopia lentis, to severe disorders including neonatal MFS, which generally leads to death within the first two years of life. The present article intends to provide an overview of mutations found in MFS and related disorders and to discuss potential genotype-phenotype correlations in MFS.

Marfan syndrome: orthopedic and genetic review

Marfan syndrome is an autosomal dominant disorder of connective tissue that affects the cardiac, eye, and skeletal systems. More than 135 mutations have been identified in the fibrillin-1 gene, localized on chromosome 15q21.1 [corrected] and responsible for the clinical manifestations of Marfan syndrome. The major orthopedic manifestations of Marfan syndrome include scoliosis, chest wall deformity, dural ectasia, joint hypermobility, and acetabular protrusion. In addition, decreased bone mineral density has been reported in patients with Marfan syndrome. This review summarizes recent developments in the genetic and orthopedic aspects of Marfan syndrome. Increased practitioner awareness of the clinical features associated with Marfan syndrome may facilitate earlier diagnosis and optimize patient treatment.

Natural history of cardiovascular manifestations in Marfan syndrome

AIMS

To investigate the natural history of mitral valve and aortic abnormalities in patients with Marfan syndrome during childhood and adolescence.

METHODS

Fifty two patients with Marfan syndrome were followed for a mean of 7.9 years. Occurrence of adverse cardiovascular outcomes was measured clinically and by ultrasound examination.

RESULTS

Mitral valve prolapse (MVP) was diagnosed in 46 patients at a mean age of 9.7 years, more than 80% of whom presented as "silent MVP". Mitral regurgitation (MR) occurred in 25 patients, aortic dilatation in 43, and aortic regurgitation (AR) in 13. Both MVP and aortic dilatation developed at a constant rate during the age period 5-20 years. In 23 patients MVP was diagnosed before aortic dilatation, in 18 the reverse occurred, and in 11 patients the two abnormalities were diagnosed simultaneously. During follow up, 21 patients showed progression of mitral valve dysfunction; progression of aortic abnormalities occurred in 13. Aortic surgery was performed in 10; two died of subsequent complications. Mitral valve surgery was performed in six. In sporadic female Marfan patients the age at initial diagnosis of MVP, MR, aortic dilatation, and AR was lowest, the grade of MR and AR most severe, the time lapse between the occurrence of MVP and subsequent MR as well as between dilatation and subsequent AR shortest, and the risk for cardiovascular associated morbidity and mortality highest.

CONCLUSIONS

During childhood and adolescence in Marfan syndrome, mitral valve dysfunction as well as aortic abnormalities develop and progress gradually, often without symptoms, but may cause considerable morbidity and mortality by the end of the second decade, especially in female sporadic patients.

The molecular genetics of Marfan syndrome and related microfibrillopathies

Mutations in the gene for fibrillin-1 (FBN1) have been shown to cause Marfan syndrome, an autosomal dominant disorder of connective tissue characterised by pleiotropic manifestations involving primarily the ocular, skeletal, and cardiovascular systems. Fibrillin-1 is a major component of the 10-12 nm microfibrils, which are thought to play a role in tropoelastin deposition and elastic fibre formation in addition to possessing an anchoring function in some tissues. Fibrillin-1 mutations have also been found in patients who do not fulfil clinical criteria for the diagnosis of Marfan syndrome, but have related disorders of connective tissue, such as isolated ectopia lentis, familial aortic aneurysm, and Marfan-like skeletal abnormalities, so that Marfan syndrome may be regarded as one of a range of type 1 fibrillinopathies. There appear to be no particular hot spots since mutations are found throughout the entire fibrillin-1 gene. However, a clustering of mutations associated with the most severe form of Marfan syndrome, neonatal Marfan syndrome, has been noted in a region encompassing exons 24 to 32. The gene for fibrillin-2 (FBN2) is highly homologous to FBN1, and mutations in FBN2 have been shown to cause a phenotypically related disorder termed congenital contractural arachnodactyly. Since mutations in the fibrillin genes are likely to affect the global function of the microfibrils, the term microfibrillopathy may be the most appropriate to designate the spectrum of disease associated with dysfunction of these molecules. The understanding of the global and the molecular functions of the fibrillin containing microfibrils is still incomplete and, correspondingly, no comprehensive theory of the pathogenesis of Marfan syndrome has emerged to date. Many, but not all, fibrillin-1 gene mutations are expected to exert a dominant negative effect, whereby mutant fibrillin monomers impair the global function of the microfibrils. In this paper we review the molecular physiology and pathophysiology of Marfan syndrome and related microfibrillopathies.

Novel exon skipping mutation in the fibrillin-1 gene: two 'hot spots' for the neonatal Marfan syndrome

The Marfan syndrome is an autosomal dominant heritable disorder of connective tissue that involves principally the skeletal, ocular, and cardiovascular systems. The most severe end of the phenotypic spectrum, the neonatal Marfan syndrome (nMFS), is characterized by pronounced atrioventricular valve dysfunction, and death often occurs within the first year of life due to congestive heart failure. Mutations in the gene coding for fibrillin-1, FBN1, are known to cause Marfan syndrome, and have been identified in almost all exons of FBN1. Here, we describe a novel mutation affecting the invariant + 1 position of the splice donor site in intron 31, associated with skipping of exon 31, in a patient with nMFS. Published reports of nMFS are reviewed and a strict definition for nMFS is suggested. If this definition is used, all nMFS mutations reported to date lie in one of two hot spots, comprising mainly missense mutations in FBN1 exons 24-27 and mutations causing skipping of exon 31 or 32.

Marfan syndrome in children and adolescents: predictive and prognostic value of aortic root growth for screening for aortic complications

OBJECTIVE

To assess and measure the diagnostic and prognostic value of individual aortic root growth in children and adolescents with Marfan syndrome.

DESIGN

From 1983 to 1996, 250 children were screened for Marfan syndrome. Serial echocardiographic aortic root measurements of 123 children (57 Marfan, 66 control) were available for evaluation of aortic root growth. Aortic root diameters were correlated with body surface area. Based on individual growth of the aortic root a discrimination formula was derived to distinguish Marfan patients from control subjects.

RESULTS

Sensitivity and specificity of this method, which were dependent on the number of measurements, were 84% and 73%, respectively, for three serial measurements. The discrimination score also predicted a five year complication free survival in all patients.

CONCLUSIONS

In children and adolescents with Marfan syndrome, aortic root growth differs significantly from subjects in whom Marfan syndrome was definitely ruled out during screening. Measurement of individual aortic root growth may serve to establish diagnosis at an early stage and is of prognostic value for occurrence of aortic complications.