Longitudinal evaluation of growth, puberty, and bone maturation in children with Williams syndrome

Brazilian growth charts for Williams-Beuren Syndrome at ages 2 to 18 years

OBJECTIVE

To develop growth charts for weight-for-age, height-for-age, and body mass index (BMI)-for-age for both genders aged 2 to 18 years for Brazilian patients with Williams-Beuren Syndrome (WBS).

METHODS

This is a multicenter, retrospective, and longitudinal study, data were collected from the medical records of boys and girls with a confirmed diagnosis of WBS in three large university centers in the state of Sao Paulo, Brazil. Growth charts stratified by gender and age in years were developed using LMSchartmaker Pro software. The LMS (Lambda Mu Sigma) method was used to model the charts . The quality of the settings was checked by worm plots.

RESULTS

The first Brazilian growth charts for weight-for-age, height-for-age, and BMI-for-age stratified by gender were constructed for WBS patients aged 2 to 18 years.

CONCLUSION

The growth charts developed in this study can help to guide family members and to improve the health care offered by health professionals.

Growth, body composition, and endocrine issues in Williams syndrome

PURPOSE OF REVIEW

Williams syndrome is a multisystem disorder caused by a microdeletion on chromosome 7q. Throughout infancy, childhood, and adulthood, abnormalities in body composition and in multiple endocrine axes may arise for individuals with Williams syndrome. This review describes the current literature regarding growth, body composition, and endocrine issues in Williams syndrome with recommendations for surveillance and management by the endocrinologist, geneticist, or primary care physician.

RECENT FINDINGS

In addition to known abnormalities in stature, calcium metabolism, and thyroid function, individuals with Williams syndrome are increasingly recognized to have low bone mineral density, increased body fat, and decreased muscle mass. Furthermore, recent literature identifies a high prevalence of diabetes and obesity starting in adolescence, and, less commonly, a lipedema phenotype in both male and female individuals. Understanding of the mechanisms by which haploinsufficiency of genes in the Williams syndrome-deleted region contributes to the multisystem phenotype of Williams syndrome continues to evolve.

SUMMARY

Multiple abnormalities in growth, body composition, and endocrine axes may manifest in individuals with Williams syndrome. Individuals with Williams syndrome should have routine surveillance for these issues in either the primary care setting or by an endocrinologist or geneticist.

Growth assessment in children with Williams-Beuren syndrome: a systematic review

Williams-Beuren syndrome (WBS) is a rare genetic disease caused by a sporadic heterozygous microdeletion in 7q11.23. It is characterized by distinctive facial appearance, cardiopathy, short stature, intellectual disability, and endocrine abnormalities. To evaluate the growth pattern of patients with WBS and to identify the prevalence of malnutrition, overweight, and obesity in this population, a systematic review of studies published in English, between 1987 and 2018, was performed following the PRISMA protocol using the PubMed, Cochrane, and BIREME databases. Original articles and articles that evaluated growth status using weight, or height, or head circumference (HC), or body mass index (BMI) of individuals with WBS were included. Case reports, articles with data from other syndromes, and articles that did not present as a central theme the evaluation of growth were not included. WBS presented specific growth pattern, characterized by intrauterine growth restriction, low weight, length, and HC at birth. This global growth delay persisted during childhood and adolescence. BMI was not different to the reference population, and obesity was not observed in childhood. The mechanisms that determine this typical growth pattern are not totally clear; however, the typical pubertal development of these patients and the intrinsic and secondary lesions caused by microdeletion at 7q11.23 seem to be the major factors involved. Conclusion: Patients with WBS have a growth pattern different from the general reference population. The reference charts for normal population should not be used for WBS patients because it often underestimate their growth. Specific growth charts for WBS patients are necessary.

Physical growth and development characteristics of children with Williams syndrome aged 0-24 months in Zhejiang Province

Background The objective of this study was to evaluate the physical growth and development characteristics of children with Williams syndrome (WS) aged 0-24 months, and provide help for early diagnosis of WS. Methods A total of 32 cases of children (17 males and 15 females) aged 0-24 months who were diagnosed with WS were enrolled between 2008 and 2017. These children were divided into four different groups: 1-6 months (six cases), 7-12 months (eight cases), 12-18 months (nine cases) and 19-24 months (nine cases). Meanwhile, a total of 32 healthy children (17 males and 15 females) were enrolled in the study from the Department of Health Care for physical examination in our hospital as the control group and matched with each divided group. Weight and height were measured, and meanwhile birth weight and height were also asked and recorded. Results There was no statistically significant difference in birth height between the two groups (p>0.05), and birth weight and the height and weight of the children with WS in the four groups were significantly lower than those of the children in the normal control (NC) group (p>0.05). When the corresponding age of WS children was compared to the Nine City Growth Curve Standards in China, 97% of cases were lagging behind in physical growth and development. Conclusions WS children often have the features of early slow physical growth, which provides certain help for the early diagnosis of WS. Therefore, for younger children, facial features combined with an accurate and objective physical growth assessment and ultrasonic cardiogram can greatly improve the screening rate.

Dental-craniofacial manifestation and treatment of rare diseases

Rare diseases are usually genetic, chronic and incurable disorders with a relatively low incidence. Developments in the diagnosis and management of rare diseases have been relatively slow due to a lack of sufficient profit motivation and market to attract research by companies. However, due to the attention of government and society as well as economic development, rare diseases have been gradually become an increasing concern. As several dental-craniofacial manifestations are associated with rare diseases, we summarize them in this study to help dentists and oral maxillofacial surgeons provide an early diagnosis and subsequent management for patients with these rare diseases.

Endocrine manifestations in children with Williams-Beuren syndrome

AIM

Endocrine abnormalities in Williams-Beuren syndrome (WBS) include growth retardation, precocious puberty, hypercalcaemia and thyroid disorders. We aimed to characterise these abnormalities in a national cohort of children with WBS.

METHODS

A retrospective study comprising a national cohort of individuals with WBS in Israel (16 males, 18 females) followed between 2010 and 2016.

RESULTS

The age at diagnosis of WBS was 1.4 ± 1.0 years. Height standard deviation score (SDS) at last visit was correlated with the midparental height SDS (r = 0.46 p = 0.007). Yet, participants did not reach their midparental height, with a difference of 1.40 ± 0.85SD (p < 0.001). Short stature below the 3rd percentile was found in 14 participants (41%). Mean insulin-like growth factor 1 SDS was low (-0.61 ± 1.64) and was correlated with the mean height SDS (r = 0.63 p = 0.038). Two participants were diagnosed with growth hormone deficiency, and initiation of growth hormone treatment improved their height velocity. A total of eight participants (23.5%) had mild hypercalcaemia, five girls (14.7%) had precocious puberty and five participants (14.7%) had thyroid abnormalities.

CONCLUSION

Individuals with WBS had a distinct growth pattern consisting of growth restriction at all ages, resulting in final adult height in the low-normal range. Precocious puberty, hypercalcaemia and thyroid abnormalities should be screened for and treated as needed.

Orthodontic Treatment and Maxillary Anterior Segmental Distraction Osteogenesis of a Subject with Williams-Beuren Syndrome and Isolated Cleft Palate: A Long-Term Follow-Up from the Age of 5 to 24 Years

Williams–Beuren syndrome (WBS) is a rare multisystem disorder caused by a hemizygous deletion of the elastin gene on chromosome 7q11.23. WBS patients have characteristic skeletal features and dental anomalies accompanied by mental retardation, a friendly outgoing personality, and mild to moderate intellectual disability or learning problems. In this case report, we present the combined orthodontic and surgical treatment of a WBS patient with an isolated cleft palate through a long-term follow-up from the age of 5 to 24 years. During the period of active treatment, comprehensive orthodontic treatment combined with maxillary anterior segmental distraction osteogenesis and prosthetic treatment using dental implants were effective in dramatically improving the patient's malocclusion. The patient's mental abilities and the cooperation shown by the patient and her family were crucial for the success of this complex and long-term treatment course.

Williams Syndrome and 15q Duplication: Coincidence versus Association

Williams syndrome is a multisystem disorder caused by contiguous gene deletion in 7q11.23, commonly associated with distinctive facial features, supravalvular aortic stenosis, short stature, idiopathic hypercalcemia, developmental delay, joint laxity, and a friendly personality. The clinical features of 15q11q13 duplication syndrome include autism, mental retardation, ataxia, seizures, developmental delay, and behavioral problems. We report a rare case of a girl with genetically confirmed Williams syndrome and coexisting 15q duplication syndrome. The patient underwent treatment for central precocious puberty and later presented with primary amenorrhea. The karyotype revealed 47,XX,+mar. FISH analysis for the marker chromosome showed partial trisomy/tetrasomy for proximal chromosome 15q (15p13q13). FISH using an ELN-specific probe demonstrated a deletion in the Williams syndrome critical region in 7q11.23. To our knowledge, a coexistence of Williams syndrome and 15q duplication syndrome has not been reported in the literature. Our patient had early pubertal development, which has been described in some patients with Williams syndrome. However, years later after discontinuing gonadotropin-releasing hormone analogue treatment, she developed primary amenorrhea.

Seven cases with Williams-Beuren syndrome: endocrine evaluation and long-term follow-up

BACKGROUND

Endocrine evaluation and long-term follow-up of seven (six male) patients with Williams-Beuren syndrome (WBS) are given.

METHOD

Data were obtained from patients' medical records. All patients underwent hormonal analyses and four of them underwent oral glucose tolerance test (OGTT).

RESULTS

They all had mild hypercalcemia. Three of them had overt hypothyroidism while subclinical hypothyroidism was detected in three patients. Four patients had thyroid hypoplasia and one had thyroid agenesis. Growth hormone deficiency (GHD) was determined in one patient. Impaired glucose tolerance (IGT) was found in three adolescents. All adolescents had early-onset puberty. The follow-up duration was 5.7±2.1 years. The mean growth velocity (GV) was 12.9±7.2 cm and 7.6±2 cm at the end of the first and second years of therapy, respectively. All patients had neurodevelopment retardation and were continuing to special education.

CONCLUSIONS

Thyroid hypoplasia is common and agenesis can be seen in patients with WBS; therefore, thyroid hormones should be measured in the newborn period and annually. GHD should be kept in mind in patients with decreased GV. IGT might be detected in patients with WBS even in adolescence.

Endocrine dysfunctions in children with Williams-Beuren syndrome

PURPOSE

Williams-Beuren syndrome (WBS) is caused by a hemizygous microdeletion of chromosome 7q11.23 and is characterized by global cognitive impairment, dysmorphic facial features, and supravalvular aortic stenosis. Endocrine dysfunctions have been reported in patients with WBS. This study was performed to investigate the frequency, clinical features, and outcomes of endocrine dysfunctions in children with WBS.

METHODS

One hundred two patients were included. The diagnosis was confirmed by chromosome analysis and fluorescent in situ hybridization. Medical charts were reviewed retrospectively to analyze endocrine dysfunctions such as short stature, precocious puberty, thyroid dysfunctions, and hypocalcemia.

RESULTS

The age at diagnosis was 3.7±4.4 years (one month to 19 years). Height- and weight-standard deviation score (SDS) were -1.1±1.1 and -1.4±1.4 at presentation, respectively. Short stature was found in 26 patients (28.3%) among those older than 2 years. Body mass index-SDS increased as the patients grew older (P<0.001). Two males and one female (2.9%) were diagnosed with central precocious puberty. Nine patients (8.8%) were diagnosed with primary hypothyroidism at age 4.0±4.3 years (one month to 12.1 years); their serum thyroid stimulating hormone and free T4 levels were 15.2±5.4 µU/mL and 1.2±0.2 ng/dL, respectively. Hypercalcemia was observed in 12 out of 55 patients under age 3 (22%) at the age of 14.3±6.6 months (7 to 28 months) with a mean serum calcium level of 13.1±2.1 mg/dL.

CONCLUSION

Endocrine dysfunctions are not uncommon causes of morbidity in patients with WBS. The severity and outcomes of their endocrine manifestations were heterogeneous. Long-term follow-up is needed to predict the prognosis of endocrine features.

Williams-beuren syndrome is a genetic disorder associated with impaired glucose tolerance and diabetes in childhood and adolescence: new insights from a longitudinal study

BACKGROUND

In adults with Williams-Beuren syndrome (WBS), a common endocrine abnormality is type 2 diabetes mellitus (T2DM) or impaired glucose tolerance (IGT). However, few and sporadic data are available in children, adolescents, and young adults with WBS.

AIM

To evaluate the frequency of IGT and T2DM in a cohort of children and young patients with WBS.

PATIENTS AND METHODS

We longitudinally evaluated 27 patients (9 males and 18 females, median age at study onset 13.6 years) with WBS. The median follow-up was 3.6 years. Variables of insulin resistance and β-cell function were evaluated in all subjects using an oral glucose tolerance test. The homeostasis model assessment (HOMA) of insulin resistance and the Matsuda index of insulin sensitivity were calculated. The study of the GCK and HNF1Α genes was performed in patients with glucose metabolism abnormalities. 45 age- and sex-matched healthy subjects and 51 age-, sex- and BMI-matched subjects were recruited as two control groups.

RESULTS

Considering nutritional status, 7 (25.9%) patients were obese, 9 (33.3%) overweight, and 11 (40.8%) normal-weight. One (3.1%) patient had acanthosis nigricans. IGT was diagnosed in 7 (25.9%) WBS patients and T2DM in 3 (11.1%). Considering all WBS patients, the median value of HOMA was 5.23 (range 2.93-14.89; insulin 24.73 ± 14.67 μU/ml; glucose 104.98 ± 16.06 mg/dl). Considering BMI values, HOMA was 11.00 (range 6.53-12.56), 5.64 (range 3.54-7.95), and 4.54 (range 3.21-5.43), and insulin was 34.53 ± 6.84, 22.76 ± 8.91, and 19.47 ± 6.01 μU/ml in obese, overweight, and normal-weight WBS patients, respectively. Comparing the results with the two control groups, WBS patients showed higher insulin values than healthy controls (p < 0.001), but similar values as the BMI-matched control group (p = n.s.). However, WBS patients showed significantly higher values of glycemia (healthy control group, p < 0.001; BMI-matched control group, p < 0.05) and HOMA (healthy control group, p < 0.001; BMI-matched control group, p < 0.05) than the two control groups. Finally, among WBS patients there was a higher number of subjects with IGT and T2DM than among healthy controls (p < 0.0001) and the BMI-matched control group (p = 0.0002).

CONCLUSION

Our data strongly suggest that IGT and T2DM may be frequently discovered in children, adolescents, and young adults with WBS. WBS should be included among the genetic syndromes associated with T2DM. Further studies are necessary to evaluate the etiopathogenesis of this aspect.

Alternative treatment for open bite Class III malocclusion in a child with Williams-Beuren syndrome

Williams-Beuren syndrome (WBS) is a rare genetic condition that affects approximately 1 in every 20,000 - 50,000 live births. WBS children have specific skeletal deformities, dental malformations and rare lingual muscle dysfunction. The need for orthodontic and orthognathic therapy has arisen and has been considered a real clinical challenge even for experienced professionals, once it requires a complex and individualized treatment plan. This study reports a case of orthopedic expansion of the maxilla, in which a modified facial mask was used for protraction of the maxillary complex associated with clockwise rotation of the maxilla. In addition, special considerations about treatment time and orthopedic outcomes are discussed.

Aging and sleep in Williams syndrome: accelerated sleep deterioration and decelerated slow wave sleep decrement

Specific developmental and aging trajectories characterize sleep electroencephalogram (EEG) of typically developing (TD) subjects. Williams syndrome (WS) is marked by sleep alterations and accelerated aging of several anatomo-functional and cognitive measures. Here we test the hypothesis of a premature aging of sleep in WS. Age-related changes of home recorded sleep EEG of 42 subjects (21 WS, 21 age- and gender matched TD subjects, age: 6-29 years) were tested by Pearson correlations and homogeneity-of-slopes analysis. Typical developmental/aging effects of sleep EEGs were observed in TD subjects. Accelerated aging in WS was confirmed by overall sleep/wake measures. Specifically, premature aging was evident in accelerated age-dependent declines in WS subjects' sleep efficiency, as well as in steeper age-related rises in wakefulness and wake after sleep onset (WASO) of the WS group. In contrast, NREM sleep-related measures indicated atypical decelerations of the developmental trends of WS subjects, characterized by the slowing down of the age-related slow wave sleep (SWS) declines mirrored by the lack of age-dependent increase in Stage 2 (S2) sleep. Age-effects in sleep EEG power spectra were not different among the groups. Objectively measured sleep disruption of subjects with WS is age-dependent and increasing with age. Moreover, these data suggest atypical pre- and postpubertal neural development in WS, with sleep/wake balance and REM sleep time indicating accelerated aging while NREM sleep composition revealing signs of an as yet unidentified, perhaps compensatory developmental delay.

Anthropometric and body-mass composition suggests an intrinsic feature in Williams-Beuren syndrome

OBJECTIVE

Although considered a well-known condition, there is only one study describing the body composition among individuals with Williams-Beuren syndrome. The aim was to characterize the nutritional status in Brazilian individuals with this condition.

METHODS

Cross-sectional study was designed to evaluate clinical and nutritional data of 17 Brazilian patients. Z-scores for height, weight, body mass index, triceps and subscapular skinfold thickness, arm circumference, arm muscle area, arm fat area were calculated. Wilcoxon's test was used to investigate differences between the z-scores of the anthropometrical measures and zero.

RESULTS

Four children were considered stunted and two severely malnourished. The z-score mean value for height was -1.14 ± 1.00 (p-value = 0.004), for weight, -0.67 ± 1.19 (p-value = 0.0443), for arm circumference, -0.94 ± 1.14 (p-value = 0.0222), for triceps skinfold thickness, -0.59 ± 0.63 (p-value = 0.0042) and for arm fat area -0.67 ± 0.67 (p-value = 0.0061).

CONCLUSION

Short stature seen in this series confirms a previous study describing this feature in a German population, which would suggest it as an intrinsic feature in Williams-Beuren syndrome. In addition, skinfold thickness measures have not been previously performed in this syndrome and detected abnormalities in fat stores in this sample. Considering this method a fast and low-cost way to evaluate body composition, similar studies could be performed in other populations in order to better characterize this issue. Morbidity related with this genetics condition and information for clinical investigation and clinical follow-up are also discussed.

Evolutionary history and adaptation from high-coverage whole-genome sequences of diverse African hunter-gatherers

To reconstruct modern human evolutionary history and identify loci that have shaped hunter-gatherer adaptation, we sequenced the whole genomes of five individuals in each of three different hunter-gatherer populations at > 60× coverage: Pygmies from Cameroon and Khoesan-speaking Hadza and Sandawe from Tanzania. We identify 13.4 million variants, substantially increasing the set of known human variation. We found evidence of archaic introgression in all three populations, and the distribution of time to most recent common ancestors from these regions is similar to that observed for introgressed regions in Europeans. Additionally, we identify numerous loci that harbor signatures of local adaptation, including genes involved in immunity, metabolism, olfactory and taste perception, reproduction, and wound healing. Within the Pygmy population, we identify multiple highly differentiated loci that play a role in growth and anterior pituitary function and are associated with height.

Bridging the gene-behavior divide through neuroimaging deletion syndromes: Velocardiofacial (22q11.2 Deletion) and Williams (7q11.23 Deletion) syndromes

Investigating the relationship between genes and the neural substrates of complex human behavior promises to provide essential insight into the pathophysiology of mental disorders. One approach to this inquiry is through neuroimaging of individuals with microdeletion syndromes that manifest in specific neuropsychiatric phenotypes. Both Velocardiofacial syndrome (VCFS) and Williams syndrome (WS) involve haploinsufficiency of a relatively small set of identified genes on the one hand and association with distinct, clinically relevant behavioral and cognitive profiles on the other hand. In VCFS, there is a deletion in chromosomal region 22q11.2 and a resultant predilection toward psychosis, poor arithmetic proficiency, and low performance intelligence quotients. In WS, there is a deletion in chromosomal region 7q11.23 and a resultant predilection toward hypersociability, non-social anxiety, impaired visuospatial construction, and often intellectual impairment. Structural and functional neuroimaging studies have begun not only to map these well-defined genetic alterations to systems-level brain abnormalities, but also to identify relationships between neural phenotypes and particular genes within the critical deletion regions. Though neuroimaging of both VCFS and WS presents specific, formidable methodological challenges, including comparison subject selection and accounting for neuroanatomical and vascular anomalies in patients, and many questions remain, the literature to date on these syndromes, reviewed herein, constitutes a fruitful "bottom-up" approach to defining gene-brain relationships.

Mechanisms and treatment of cardiovascular disease in Williams-Beuren syndrome

Williams-Beuren syndrome (WBS) is a microdeletion disorder caused by heterozygous loss of approximately 1.5-Mb pairs of DNA from chromosome 7. Patients with WBS have a characteristic constellation of medical and cognitive findings, with a hallmark feature of generalized arteriopathy presenting as stenoses of elastic arteries and hypertension. Human and mouse studies establish that defects in the elastin gene, leading to elastin haploinsufficiency, underlie the arteriopathy. In this review we describe potential links between elastin expression and arteriopathy, possible explanations for disease variability, and current treatment options and their limitations, and we propose several new directions for the development of nonsurgical preventative therapies based on insights from elastin biology.

New height, weight and head circumference charts for British children with Williams syndrome

AIM

To produce a growth reference for British children with Williams syndrome.

METHODS

The children and adults recruited into the study were all affiliated to the Williams Syndrome Foundation, a parent support group founded in 1979. They have all been shown to have a deletion of chromosome 7q11.23. One growth nurse (WRS) prospectively measured the weight, height and head circumference of individuals from 19 regions in Great Britain including Scotland, England and Wales. 169 children and adults were measured on up to four occasions between 2001 and 2004 (275 measurements). In addition, retrospective data were obtained from the hospital notes of 67 of these individuals (586 measurements). Centile curves were constructed using Cole's LMS method.

RESULTS

The centile charts differ from charts previously derived in the USA and Germany and provide more appropriate standards for the British population.

CONCLUSIONS

We propose that these charts be adopted for routine clinical practice as abnormalities in growth are an important feature of this syndrome.

Presenting phenotype and clinical evaluation in a cohort of 22 Williams-Beuren syndrome patients

Williams-Beuren syndrome (WS) is a rare multi-system genomic disorder, caused by 7q11.23 microdeletion with a prevalence of 1/7500-1/20,000 live births. Clinical phenotype includes typical facial dysmorphism (elfin face), mental retardation associated with a peculiar neuropsychological profile and congenital heart defects. We investigated 22 WS patients (mean age of 9.7 years, range 1 day to 39 years) with a multi-specialist follow-up protocol comprehensive of neuropsychological, cardiologic, nephrologic, ophthalmologic, endocrinologic, gastroenterologic, odontostomatologic and orthopaedic evaluations. The mean age at diagnosis was 5.38 years, being 1.02 years when genetic evaluation was requested for congenital heart defects (CHD) and 10.68 years in case of mental retardation and/or abnormal neuropsychological profile without an evident CHD. All patients showed facial dysmorphisms, with supravalvular aortic stenosis (SVAS) as the most common cardiovascular anomaly (12/22), followed by peripheral pulmonary stenosis (9/22); interestingly, in one patient we detected a total anomalous pulmonary venous return (TAPVR), confirming the possible association of this rare CHD with WS. Hypertension was detected by 24-h ambulatory blood pressure monitoring in 7/22 cases. A cognitive assessment was performed in 13 patients older than 6 years, showing various degrees of mental retardation in 12 and a normal intelligence quotient (IQ) in a single patient; evaluation of developmental milestones revealed various grades of developmental delay in all the patients younger than 6 years. Chiari malformation type 1 was found in 3 patients. Our study underlines a remarkable diagnostic delay in patients who present to genetic evaluation because of mental retardation and/or peculiar neuropsychological profile lacking an evident cardiopathy and confirms the multi-systemic nature of WS leading to a high clinical presentation's variability and complex follow-up strategies.

Hemizygosity at the NCF1 gene in patients with Williams-Beuren syndrome decreases their risk of hypertension

Williams-Beuren syndrome (WBS), caused by a heterozygous deletion at 7q11.23, represents a model for studying hypertension, the leading risk factor for mortality worldwide, in a genetically determined disorder. Haploinsufficiency at the elastin gene is known to lead to the vascular stenoses in WBS and is also thought to predispose to hypertension, present in approximately 50% of patients. Detailed clinical and molecular characterization of 96 patients with WBS was performed to explore clinical-molecular correlations. Deletion breakpoints were precisely defined and were found to result in variability at two genes, NCF1 and GTF2IRD2. Hypertension was significantly less prevalent in patients with WBS who had the deletion that included NCF1 (P=.02), a gene coding for the p47(phox) subunit of the NADPH oxidase. Decreased p47(phox) protein levels, decreased superoxide anion production, and lower protein nitrotyrosination were all observed in cell lines from patients hemizygous at NCF1. Our results indicate that the loss of a functional copy of NCF1 protects a proportion of patients with WBS against hypertension, likely through a lifelong reduced angiotensin II-mediated oxidative stress. Therefore, antioxidant therapy that reduces NADPH oxidase activity might have a potential benefit in identifiable patients with WBS in whom serious complications related to hypertension have been reported, as well as in forms of essential hypertension mediated by a similar pathogenic mechanism.

Medical considerations in dental treatment of children with Williams syndrome

Williams syndrome is a rare disorder that was first described in 1961. It is thought to be caused by a microdeletion in the long arm of chromosome 7 at 7q11.23 and is a multisystem, congenital, and panethnic disorder characterized by a number of developmental and physical abnormalities, including congenital cardiovascular abnormalities, mental retardation and neurological features, growth deficiency, genitourinary manifestation, gastrointestinal and musculoskeletal problems, behavioral characteristics, craniofacial features, ophthalmologic features, and dental problems. We describe cases of children with Williams syndrome treated in the department of Pediatric Dentistry of the Hadassah School of Dental Medicine, Jerusalem, Israel. The different treatments rendered to these children are discussed followed by general remarks drawn from those treatments and from a literature review. We conclude that sedation can be helpful in the younger age group to reduce anxiety and uncooperative behavior during minimal dental treatments. Treatment under general anesthesia seems more appropriate for older children and adolescents. Special attention should be given to initial evaluation of these patients, especially because with age aortic stenosis tends to intensify, which together with the progressive renal impairment can escalate blood pressure elevation.

Central precocious puberty in a girl with Williams syndrome: the result of treatment with GnRH analogue

Williams syndrome (WS) is a well-known microdeletion syndrome characterized by specific facial features, retardation in growth and development, typical personality and cardiac defects. Poor growth potential is further affected by central precocious puberty (CPP) which is frequent in these patients. A WS patient with CPP is presented, whose pubertal development and bone age progression were arrested by administration of GnRH analogues. The case is reported to discuss the role of GnRH analogues for management of CPP in patients with WS.

Increased prevalences of left-handedness and left-eye sighting dominance in individuals with Williams-Beuren syndrome

Handedness and eye sighting dominance were assessed in a sample of 50 individuals (25 male, 25 female; aged 5-38 years) with Williams-Beuren syndrome (WBS). The prevalences of left-handedness and left-eyedness were compared to the normative prevalences in the general population. We found significantly higher prevalences of left-handedness and left-eyedness in the WBS sample. The higher prevalences were more salient in younger than in older individuals and in male than in female individuals. We suggest that the increased prevalence of left-handedness in WBS is a consequence of a slower maturation rate, which allows deviation from a predetermined laterality pattern.

Sigmoid diverticulitis in patients with Williams-Beuren syndrome: relatively high prevalence and high complication rate in young adults with the syndrome

In a retrospective survey of 128 adults with Williams-Beuren syndrome (age range 18-62 years) sigmoid diverticulitis was reported in 10 patients (2 f, 8 m). The diagnosis of diverticulitis had been made between the ages of 17.1 and 39.6 years. An additional four patients (age range 23.5-32.2 years) had presented with sigmoid diverticulosis. In eight patients the course of the disease was complicated, some of them having to undergo multiple surgery. Conservative therapy was successful in only one female and one male patient with diverticulitis. Thus, we conclude that there is an increased prevalence of sigmoid diverticulitis in adult patients with Williams-Beuren syndrome (8% vs. 2% in the normal population in the age group below 40 years).

Risk of sudden death in the Williams-Beuren syndrome

Williams-Beuren syndrome (WBS) is a genetic disorder characterized by a distinctive facial gestalt, mental retardation, mild growth deficiency, and cardiovascular disease. The occurrence of sudden death in the WBS is known from several case reports, but information about the risk of sudden death as derived from the data of a large cohort of patients is lacking. We analyzed the data of 293 WBS patients who had been treated for 43 years at the same two institutions. We thus collected 5,190 patient years without loss to follow-up. During this period ten patients died. Five of them died from: reticulosarcoma (1), after accident (1), heart failure (1), following heart surgery (2). Of the remaining five patients, four died suddenly and one died of unknown cause suggestive of sudden cardiac death. Thus, the incidence of sudden death in our WBS cohort amounts to 1/1,000 patient years. This risk of sudden death is comparable to that following surgery for congenital heart disease, and is 25-100-fold higher compared to the age-matched normal population.

Síndrome de Williams-Beuren: presentación de 82 casos

OBJECTIVE

We performed a retrospective review of a series of 82 cases of Williams-Beuren syndrome (WBS) and associated diseases.

MATERIAL AND METHODS

A series of 82 patients (47 males and 35 females) who consulted at the hospital because of mental retardation and/or congenital cardiopathy were included. The patients were studied mainly from a neurological and cardiological point of view, and secondarily because of endocrinological and nephrological problems. Since description of the chromosomal abnormalities provoking the syndrome, we perform karyotyping in all patients with suspected WBS.

RESULTS

Alterations mainly consisted of distinctive facial appearance (100 %), mental retardation with friendly behavior (90 %), congenital cardiopathy (85.4 %), mostly consisting of supravalvular aortic stenosis (72 %), with (12 %) or without (60 %) pulmonary stenosis, and behavior typical of attention deficit-hyperactivity disorder, which usually manifested at the age of 4 to 5 years in both boys and girls. Approximately 90 % started to walk and speak later than average. Birthweight was below 3000 g in 65 % of the patients in whom this datum was included in the medical record. Eleven of the 13 patients (84.5 %) studied showed the typical deletion of WBS.

CONCLUSION

Study of patients with WBS should be multidisciplinary. Most patients require help during schooling and subsequent vocational guidance.

Central precocious puberty in girls with Williams syndrome

We report an estimated prevalence of precocious puberty of 1 in 5 to 6 girls with Williams syndrome (18.3%). Mean menarcheal age of 86 girls with Williams syndrome was 11.5 +/- 1.7 (+/-SD) years. Distribution of menarcheal age was significantly different from that in normal girls (12.9 +/- 1.1 years; n = 759).

Treatment of central precocious puberty

This chapter describes several aspects of the management of treatment in girls and boys with central precocious puberty. Although there is some controversy about the indication for gonadotrophin releasing hormone (GnRH) agonist treatment in the literature, a list of clear indications is presented and monitoring requirements for treatment are discussed with reference to the pertinent literature. The development of clinical, psychological, hormonal, sonographical and auxological parameters that can be expected during GnRH agonist treatment is described in detail. In view of the scant evidence-based knowledge, we review the final outcome of patients treated with GnRH agonists with respect to reversibility of hormonal suppression, reproductive function, final height and side effects. The data published so far show that GnRH agonist treatment using the modern depot preparations is not only convenient but also safe, with relatively minor side effects. The outcome in terms of final height is favourable in the majority of patients.

Simple method for developing percentile growth curves for height and weight

The present paper demonstrates the ease of use of method I by Preece and Baine ([1978] Ann Hum Biol 5:1-24) in generating smoothed growth curves for both height and weight. Using the National Center for Health Statistics (NCHS) growth curve data, smoothed curves were developed and compared to those produced using the least-squares-cubic-spline method. Based on the lower sum of squares and better fit of shape as indicated by residual examination, it was concluded that the method I curve fitting procedure by Preece and Baine ([1978] Ann Hum Biol 5:1-24) fit centile growth curves for height and weight in 2-18-year-old male and female children as well as, if not better than, the least-squares-cubic-spline method used in developing the 1979 NCHS growth curves. Further, as this paper demonstrates, smoothed curves can be generated on a desktop computer using readily available software (the SOLVER function within Microsoft EXCEL).

Williams syndrome: from genotype through to the cognitive phenotype

Williams syndrome, due to a contiguous gene deletion at 7q11.23, is associated with a distinctive facial appearance, cardiac abnormalities, infantile hypercalcemia, and growth and developmental retardation. The deletion is approximately 1.5Mb and includes approximately 17 genes. Large repeats containing genes and pseudogenes flank the deletion breakpoints, and the mutation mechanism commonly appears to be unequal meiotic recombination. Elastin hemizygosity is associated with supravalvular aortic stenosis and other vascular stenoses. LIM Kinase 1 hemizygosity may contribute to the characteristic cognitive profile. The relationship of the other deleted genes to phenotypic features is not known. People with Williams syndrome tend to be over friendly-though anxious-and lack social judgement skills. They exhibit an uneven cognitive-linguistic profile together with mild to severe mental retardation. Analysis of the cognitive phenotype based on analyses of the mental processes underlying overt behavior demonstrates major differences between normal and WS subjects although for some areas, such as face processing, WS subjects can achieve near normal scores. Cognitive analysis of patients with small deletions in 7q11.23 which include elastin and LIM Kinase 1 have revealed varying results and it is premature to draw genotype-phenotype correlations.

Familial Williams-Beuren syndrome showing varying clinical expression

Williams-Beuren syndrome (WBS) is a contiguous gene syndrome that occurs mainly sporadically, with an estimated frequency of 1:13,700 to 1:25,000 [Grimm and Wesselhoeft, 1980; Martin et al., 1984; Udwin, 1990]. The cases of monozygotic twins concordant for WBS and dizygotic twins discordant for the syndrome have been reported. In addition, a few familial cases have been described since 1993. The clinical diagnosis has been supported by molecular genetic findings in only two patients, however. We herein report on two families in which the WBS was inherited in girls from their mothers. All four patients showed the typical hemizygous deletion at 7q11.23 [46,XX, ish,del(7)(q11.23q11.23) (ELN/LIMK1/D7S-613x1, D7S486/D7S522x2)], but the clinical picture was strikingly variable within and between families.