Action against birth defects: if not now, when?

BACKGROUND: More children are surviving through interventions to address the infectious causes of under-5 mortality; subsequently, the proportion of deaths caused by birth defects is increasing. Prevention, diagnosis, treatment and care interventions for birth defects are available but are needed where the burden is highest, low-and-middle-income countries. OBJECTIVES: A selection of birth defect focused publications, conferences, and World Health Assembly resolutions from 2000 to 2017 show that global efforts were made to raise the profile of birth defects in global public health. However, recent donor support and national government interest has waned. Without concerted global action to improve primary prevention and care for children born with birth defects, the Sustainable Development Goal targets for child survival will not be met. RESULTS: Birth defects make up 8% and 10% of global under-5 and neonatal deaths respectively, making them significant contributors to preventable loss of life for children. Survivors face long-term morbidity and lifelong disability which compounds the health and economic woes of individuals, families, communities and society as a whole. Demographic changes in sub-Saharan Africa portend a growing number of births with 1.6 billion projected from 2021 to 2050. More births and better survival without effective prevention and treatment for birth defects translates into more mortality and disability from birth defects. CONCLUSIONS: We recommend interventions for prevention of birth defects. These are evidenced-based and affordable, but require low- and middle-income countries to strengthened their health systems. Action against birth defects now will prevent premature deaths and long-term disability, and lead to stronger, more resilient health systems.

Long-term remission of infantile Takayasu arteritis associated with germline CBL syndrome after allogeneic hematopoietic stem cell transplantation: A case report and literature review.

Takayasu arteritis (TA) is a large-vessel vasculitis that rarely presents in infancy. Casitas B-lineage lymphoma (CBL) syndrome is a rare genetic disorder due to heterozygous CBL gene germline pathogenic variants that is characterized by a predisposition to develop juvenile myelomonocytic leukemia (JMML). Vasculitis, including TA, has been reported in several patients. Herein, we describe a patient with CBL syndrome, JMML, and TA, developing long-term remission of this vasculitis after allogeneic hematopoietic stem cell transplant (HSCT), and perform a literature review of CBL syndrome with vasculitis or vasculopathy. We report a female patient with growth delay, developmental issues, and congenital heart disease who was admitted at 14 months of age with massive splenomegaly, lymphadenopathy, fever, and hypertension. Body imaging studies revealed arterial stenosis and wall inflammation of the aorta and multiple thoracic and abdominal branches. Whole exome sequencing revealed a pathogenic variant in CBL with loss of heterozygosity in blood cells, diagnosing CBL syndrome, complicated by JMML and TA. Allogeneic HSCT induced remission of JMML and TA, permitting discontinuation of immunosuppression after 12 months. Six years later, her TA is in complete remission off therapy. A literature review identified 18 additional cases of CBL syndrome with vasculitis or vasculopathy. The pathogenesis of vasculitis in CBL syndrome appears to involve dysregulated T cell function and possibly increased angiogenesis. This case advances the understanding of vascular involvement in CBL syndrome and of the genetic, immune, and vascular interplay in TA, offering insights for treating CBL syndrome and broader TA.

Phenotypic and mutational spectrum of ROR2-related Robinow syndrome.

Robinow syndrome is characterized by a triad of craniofacial dysmorphisms, disproportionate-limb short stature, and genital hypoplasia. A significant degree of phenotypic variability seems to correlate with different genes/loci. Disturbances of the noncanonical WNT-pathway have been identified as the main cause of the syndrome. Biallelic variants in ROR2 cause an autosomal recessive form of the syndrome with distinctive skeletal findings. Twenty-two patients with a clinical diagnosis of autosomal recessive Robinow syndrome were screened for variants in ROR2 using multiple molecular approaches. We identified 25 putatively pathogenic ROR2 variants, 16 novel, including single nucleotide variants and exonic deletions. Detailed phenotypic analyses revealed that all subjects presented with a prominent forehead, hypertelorism, short nose, abnormality of the nasal tip, brachydactyly, mesomelic limb shortening, short stature, and genital hypoplasia in male patients. A total of 19 clinical features were present in more than 75% of the subjects, thus pointing to an overall uniformity of the phenotype. Disease-causing variants in ROR2, contribute to a clinically recognizable autosomal recessive trait phenotype with multiple skeletal defects. A comprehensive quantitative clinical evaluation of this cohort delineated the phenotypic spectrum of ROR2-related Robinow syndrome. The identification of exonic deletion variant alleles further supports the contention of a loss-of-function mechanism in the etiology of the syndrome.

Neural tube defects prevalence does not increase after modification of the folic acid fortification program in Chile.

BACKGROUND: In 2000, Chile's Ministry of Health mandated fortification of wheat flour with folic acid at a concentration of 2.2 mg/kg to prevent neural tube defects (NTDs), resulting in a 50% reduction in NTD prevalence. Concerns about possible collateral effects of high folic acid intake led, in 2009, to decrease the folic acid fortification to 1.8 mg/kg of flour. Our study evaluated the impact of this modification on the prevalence of NTDs in Santiago. METHODS: This study measured the prevalence of NTDs in live births and stillbirths born in Santiago. We calculated prevalence ratios (PR) and 95% confidence intervals (CI) between pre-folic acid fortification (1999-2000), post-folic acid fortification (2001-2009), and post-modified folic acid fortification (2010-2015) periods for all NTDs and their specific types. We used chi-square tests to analyze proportions, and a Joinpoint regression to visualize prevalence time trends. RESULTS: The NTD prevalence for the period 2001-2015 was 8.9 per 10,000 births, which represents a 48% reduction (PR = 0.52; 95% CI = 0.45-0.61; p < .001) from the pre-folic acid fortification period. During 2010-2015, the NTD prevalence was 9.5/10,000 births, which was higher, but not statistically significantly different from 2001 to 2009 prevalence of 8.6/10,000 (PR = 1.11; 95% CI = 0.96-1.30, p = .17). CONCLUSIONS: Decreasing the concentration of folic acid fortification was not associated with a statistically significant change in the prevalence of NTDs. Mandatory folic acid fortification continues to be a safe and highly effective policy to prevent NTDs. Future studies should evaluate the prevalence of NTDs across Chile and adherence to folic acid fortification mandates.

Prevalence of microcephaly: the Latin American Network of Congenital Malformations 2010-2017.

Objective: The Latin American Network of Congenital Malformations: ReLAMC was established in 2017 to provide accurate congenital anomaly surveillance. This study used data from ReLAMC registries to quantify the prevalence of microcephaly from 2010 to 2017 (before, during and after the Zika virus epidemic). Design: Nine ReLAMC congenital anomaly registries provided case-level data or aggregate data for any live births, still births or terminations of pregnancy with microcephaly. Births to pregnant women infected with Zika virus first occurred in Brazil in 2015, and in the remaining registry areas in 2016 with the exception of Chile that did not experience Zika virus. Therefore the prevalence of microcephaly for 2010-2014 and individual years 2015, 2016 and 2017 was estimated using multilevel random effect Poisson models. Clinical classification and characteristics of the cases were compared pre and post Zika for all centres providing individual case-level data. Results: The prevalence of microcephaly for all registries excluding Brazil was 2.3 per 10 000 (95% CI 2.0 to 2.6) for 2010-2014 rising to 5.4 (95% CI 4.8 to 6.0) in 2016 and 5.9 (95% CI 5.3 to 6.6) in 2017. Brazil had a prevalence of 0.6 per 10 000 (95% CI 0.5 to 0.6) in 2010-2014, rising to 5.8 (95% CI 5.6 to 6.1) in 2015, 8.0 (95% CI 7.6 to 8.3) in 2016 and then falling in 2017. Only 29 out of 687 cases of microcephaly were reported as congenital Zika syndrome in countries excluding Brazil. Conclusions: The prevalence of microcephaly was influenced both by Zika causing congenital Zika syndrome and by increased reporting awareness.

Skeletal dysplasias in Latin America.

Skeletal dysplasias (SD) are disturbances in growth due to defects intrinsic to the bone and/or cartilage, usually affecting multiple bones and having a progressive character. In this article, we review the state of clinical and research SD resources available in Latin America, including three specific countries (Brazil, Argentina, and Chile), that have established multidisciplinary clinics for the care of these patients. From the epidemiological point of view, the SD prevalence of 3.2 per 10,000 births from nine South American countries included in the ECLAMC network represents the most accurate estimate not just in Latin America, but worldwide. In Brazil, there are currently five groups focused on SD. The data from one of these groups including the website www.ocd.med.br, created to assist in the diagnosis of SD, are highlighted showing that telemedicine for this purpose represents a good strategy for the region. The experience of more than 30 years of the SD multidisciplinary clinic in an Argentinian Hospital is presented, evidencing a solid experience mainly in the follow-up of the most frequent SD, especially those belonging the FGFR3 group and OI. In Chile, a group with 20 years of experience presents its work with geneticists and pediatricians, focusing on diagnostic purposes and clinical management. Altogether, although SD health-care and research activities in Latin America are in their early stages, the experience in these three countries seems promising and stimulating for the region as a whole.

Identification of c.1531C>T Pathogenic Variant in the CDH1 Gene as a Novel Germline Mutation of Hereditary Diffuse Gastric Cancer.

Germline pathogenic variants in the CDH1 gene are a well-established cause of hereditary diffuse gastric cancer (HDGC) syndrome. The aim of this study was to characterize CDH1 mutations associated with HDGC from Chile, a country with one of the highest incidence and mortality rates in the world for gastric cancer (GC). Here, we prospectively include probands with family history/early onset of diffuse-type of GC. The whole coding sequence of the CDH1 gene was sequenced from genomic DNA in all patients, and a multidisciplinary team managed each family member with a pathogenic sequence variant. Thirty-six cases were included (median age 44 years/male 50%). Twenty-seven (75%) patients had diffuse-type GC at ≤50 years of age and 19 (53%) had first or second-degree family members with a history of HDGC. Two cases (5.5%) carried a non-synonymous germline sequence variant in the CDH1 gene: (a) The c.88C>A missense variant was found in a family with three diffuse-type GC cases; and (b) c.1531C>T a nonsense pathogenic variant was identified in a 22-year-old proband with no previous family history of HDGC. Of note, six family members carry the same nonsense pathogenic variant. Prophylactic gastrectomy in the proband's sister revealed stage I signet-ring cell carcinoma. The finding of 1531C>T pathogenic variant in the CDH1 in proband with no previous family history of HDGC warrants further study to uncover familial clustering of disease in CDH1 negative patients. This finding may be particularly relevant in high incidence countries, such as the case in this report.

[Pseudohypoparathyroidism: report of two cases of late presentation]. / Pseudohipoparatiroidismo de presentación tardía: reporte de dos casos.

Pseudohypoparathyroidism (PHP) is a group of rare genetic disorders that share organ targeted resistance to the action of parathyroid hormone (PTH) as a common feature. Biochemically, they may present with hypocalcemia, hyperphosphatemia and elevated PTH. Some forms present with a specific phenotype: short stature, round facies, short neck, obesity, brachydactyly and subcutaneous calcifications, called Albrigth's Hereditary Osteodystrophy (AHO). This spectrum of disorders are caused by several alterations in the gene coding for the alpha subunit of the G protein (GNAS): an ubiquitous signaling protein that mediates the action of numerous hormones such as PTH, TSH, gonadotropins, and ACTH, among others. According to their inheritance with maternal or paternal imprinting, they may manifest in a diversity of clinical forms. Although most commonly diagnosed during childhood, PHP may manifest clinically during adolescence or early adulthood. We report two late presenting cases of pseudohypoparathyroidism. A 21-year-old female with biochemical abnormalities characteristic of pseudohypoparathyroidism who was misdiagnosed as epilepsy and a 13-year-old boy with the classic AHO phenotype but without alterations in phospho-calcium metabolism, compatible with pseudopseudohypoparathyrodism.

Pseudohipoparatiroidismo de presentación tardía: reporte de dos casos / Pseudohypoparathyroidism: report of two cases of late presentation

Pseudohypoparathyroidism (PHP) is a group of rare genetic disorders that share organ targeted resistance to the action of parathyroid hormone (PTH) as a common feature. Biochemically, they may present with hypocalcemia, hyperphosphatemia and elevated PTH. Some forms present with a specific phenotype: short stature, round facies, short neck, obesity, brachydactyly and subcutaneous calcifications, called Albrigth's Hereditary Osteodystrophy (AHO). This spectrum of disorders are caused by several alterations in the gene coding for the alpha subunit of the G protein (GNAS): an ubiquitous signaling protein that mediates the action of numerous hormones such as PTH, TSH, gonadotropins, and ACTH, among others. According to their inheritance with maternal or paternal imprinting, they may manifest in a diversity of clinical forms. Although most commonly diagnosed during childhood, PHP may manifest clinically during adolescence or early adulthood. We report two late presenting cases of pseudohypoparathyroidism. A 21-year-old female with biochemical abnormalities characteristic of pseudohypoparathyroidism who was misdiagnosed as epilepsy and a 13-year-old boy with the classic AHO phenotype but without alterations in phospho-calcium metabolism, compatible with pseudopseudohypoparathyrodism.

Consenso de la Rama de Genética de la Sociedad Chilena de Pediatría sobre las anomalías congénitas de mal pronóstico vital (ACMPV): Genetics Consensus Committee / Congenital anomalies of poor prognosis

Introducción: La rama de genética de la Sociedad Chilena de Pediatría, en relación con el proyecto de ley que regula la despenalización de la interrupción voluntaria del embarazo en 3 causales, centrándose en la segunda causal que considera al «embrión o feto que padezca una alteración estructural congénita o genética incompatible con la vida extrauterina¼, se reunió para discutir conforme a la evidencia científica qué anomalías congénitas (AC) podrían ser incluidas en el proyecto de ley. Metodología: Los expertos en genética clínica se centraron en 10 AC. Se efectuó revisión bibliográfica y una reunión extraordinaria para discutirla. Resultados: Se acordó no emplear el término «incompatible con la vida extrauterina¼, pues existen excepciones de sobrevidas más prolongadas y cambiar por «anomalía congénita de mal pronóstico vital (ACMPV)¼. Se evaluaron 10 AC: defectos graves de cierre del tubo neural: anencefalia, iniencefalia y craneorraquisquisis, hipoplasia pulmonar, feto acardio, ectopia cordis, triploidía no mosaico, complejo limb body wall, anomalía body stalk, trisomía 13, trisomía 18 y agenesia renal bilateral. Se analizaron los hallazgos sobre prevalencia, historia natural, métodos diagnósticos prenatales, sobrevida, casos descritos de sobrevida prolongada. Para catalogarlas como ACMPV se consideraron: sobrevida posnatal, existencia de tratamientos y evolución posterior e historia natural sin intervenciones. Conclusión: Las ACMPV incluidas serían: anencefalia, hipoplasia pulmonar severa, feto acardio, ectopia cordis cervical, triploidía no mosaico, complejo limb body wall, anomalía body stalk, trisomía 13 no mosaico, trisomía 18 no mosaico y agenesia renal bilateral. Se requiere para el diagnóstico que toda mujer gestante tenga acceso a evaluaciones ecográficas de anatomía fetal, y en ocasiones a resonancia magnética y estudios citogenéticos y moleculares.

Introduction: The Genetic Branch of the Chilean Society of Paediatrics, given the draft Law governing the decriminalisation of abortion on three grounds, focusing on the second ground, which considers the "embryo or foetus suffering from a congenital structural anomaly or a genetic disorder incompatible with life outside the womb", met to discuss the scientific evidence according to which congenital anomalies (CA) may be included in this draft law. Methodology: Experts in clinical genetics focused on 10 CA, reviewed the literature evidence, and met to discuss it. Results: It was agreed not to use the term "incompatible with life outside the womb", as there are exceptions and longer survivals, and change to "congenital anomaly of poor prognosis (CAPP)". Ten CA were evaluated: serious defects of neural tube closure: anencephaly, iniencephaly and craniorachischisis, pulmonary hypoplasia, acardiac foetus, ectopia cordis, non-mosaic triploidy, "limb body wall" complex, "body stalk" anomaly, trisomy 13, trisomy 18, and bilateral renal agenesis. Findings on the prevalence, natural history, prenatal diagnostic methods, survival, and reported cases of prolonged survival were analysed. Post-natal survival, existence of treatments, and outcomes, as well as natural history without intervention, were taken into account in classifying a CA as a CAPP. Conclusion: A CAPP would be: anencephaly, severe pulmonary hypoplasia, acardiac foetus, cervical ectopia cordis, non-mosaic triploidy, limb body wall complex, body stalk anomaly, non-mosaic trisomy 13, non-mosaic trisomy 18, and bilateral renal agenesis. For their diagnosis, it is required that all pregnant women have access to assessments by foetal anatomy ultrasound and occasionally MRI, and cytogenetic and molecular testing.

[Congenital anomalies of poor prognosis. Genetics Consensus Committee]. / Consenso de la Rama de Genética de la Sociedad Chilena de Pediatría sobre las anomalías congénitas de mal pronóstico vital (ACMPV).

INTRODUCTION: The Genetic Branch of the Chilean Society of Paediatrics, given the draft Law governing the decriminalisation of abortion on three grounds, focusing on the second ground, which considers the "embryo or foetus suffering from a congenital structural anomaly or a genetic disorder incompatible with life outside the womb", met to discuss the scientific evidence according to which congenital anomalies (CA) may be included in this draft law. METHODOLOGY: Experts in clinical genetics focused on 10 CA, reviewed the literature evidence, and met to discuss it. RESULTS: It was agreed not to use the term "incompatible with life outside the womb", as there are exceptions and longer survivals, and change to "congenital anomaly of poor prognosis (CAPP)". Ten CA were evaluated: serious defects of neural tube closure: anencephaly, iniencephaly and craniorachischisis, pulmonary hypoplasia, acardiac foetus, ectopia cordis, non-mosaic triploidy, "limb body wall" complex, "body stalk" anomaly, trisomy 13, trisomy 18, and bilateral renal agenesis. Findings on the prevalence, natural history, prenatal diagnostic methods, survival, and reported cases of prolonged survival were analysed. Post-natal survival, existence of treatments, and outcomes, as well as natural history without intervention, were taken into account in classifying a CA as a CAPP. CONCLUSION: A CAPP would be: anencephaly, severe pulmonary hypoplasia, acardiac foetus, cervical ectopia cordis, non-mosaic triploidy, limb body wall complex, body stalk anomaly, non-mosaic trisomy 13, non-mosaic trisomy 18, and bilateral renal agenesis. For their diagnosis, it is required that all pregnant women have access to assessments by foetal anatomy ultrasound and occasionally MRI, and cytogenetic and molecular testing.

[Prevalence of genetic diseases in admissions to a tertiary care hospital pediatric service]. / Impacto de la enfermedad genética en los ingresos hospitalarios en un Servicio de Pediatría.

BACKGROUND: With the epidemiological changes, the role of genetic factors as a cause of morbidity and mortality is increasing, changing disease patterns of patients admitted to pediatric hospitals. AIM: To describe the prevalence of genetic diseases (GD) in patients admitted to a tertiary-care hospital Pediatric Service. MATERIAL AND METHODS: The clinical records of consecutive admissions to a Pediatric Service of a clinical hospital in 2011 were reviewed. Two categories were assigned: with GD and without GD. Both groups were compared according to days of hospitalization, type of admission, readmissions and mortality. RESULTS: We reviewed the 98.1% of the 1,781 total annual admissions (1,459 cases), 322 of them were readmissions (187 cases). The mean age at admission was 54.8 ± 54 months and 55% were male. The mean hospitalization length was 4.9 ± 10 days. Of total admissions and individual cases, 52.7% (938/1,781) and 48% (705/1,459) were cases with GD, respectively. Within this group, 85% (597/705) were sub-categorized as having a significant genetic base. The differences between gender, age average income and hospital mortality were not significant between the two categories. Readmissions were more common for GD than for patients without GD (Odds ratio (OR): 2.6, confidence intervals (CI): 1.9-3.6). Average hospital stay was 27% higher among GD patients (p < 0.01). CONCLUSIONS: Our findings confirm the high prevalence of GD in pediatric hospitals (52.7%), with a higher risk for readmission in cases with GD compared with those without GD.

Resultado de estudio prenatal invasivo para el diagnóstico de aneuploidía en el Hospital Sótero del Río / Results of an invasive prenatal study for the diagnosis of aneuploidy at Hospital Sótero del Río

ANTECEDENTES: Las aneuploidías y malformaciones congénitas son causa importante de morbi-mortalidad perinatal e infantil en Chile. OBJETIVO: Evaluar la realidad local del diagnóstico genético antenatal para mejorar el resultado perinatal. MÉTODOS: Estudio retrospectivo y descriptivo. Se realizó amniocentesis a embarazadas con indicación de estudio genético prenatal por sospecha ecográfica de alteraciones cromo-sómicas, entre octubre de 2010 y marzo de 2015, en el Hospital Sótero del Río. RESULTADOS: Los hallazgos ecográficos más frecuentes fueron: cardiopatías congénitas, malformaciones del sistema nervioso central y restricción de crecimiento fetal precoz. 164 pacientes aceptaron el estudio invasivo antenatal, obteniéndose resultados de 154. El promedio de edad materna y edad gestacional del examen fueron 30 años y 27+3 semanas, respectivamente. En embarazos con trisomía 21 y 13, el 71% de las pacientes tenía sobre 35 años. Un 31% de las muestras presentaron cariotipo anormal, siendo la más frecuente la trisomía 21 (14%), trisomía 18 (9%), monosomía X (4,5%) y trisomía 13 (2,6%). CONCLUSIÓN: El diagnóstico genético prenatal permite un adecuado manejo perinatal, coordinación apropiada entre las unidades de Obstetricia y Neonatología, y la preparación de las pacientes y sus familias para un pronóstico perinatal adverso.

BACKGROUND: Malformations and aneuploidy are a major cause of perinatal morbidity and mortality in Chile. Invasive techniques are offered to determine the fetal karyotype, when there is an abnormal finding in the ultrasound. AIMS: To assess the local situation of prenatal genetic diagnosis to improve the management of this population. METHODS: This is a retrospective and descriptive study of patients from october 2010 to march 2015, who had an amniocentesis for genetic testing due suspected fetal malformations or aneu-ploidy. RESULTS: The sonographic findings most frequently found were: congenital heart disease, malformations of the central nervous system and early growth restrictions. 164 patients agree to perform invasive prenatal genetic, obtaining 154 results. The average maternal age was 30 years and the mean gestational age at amniocentesis was 27+3 weeks. In trisomy 21 pregnancies, 71% of patients were higher than 35 years. 31% of the samples had abnormal karyotype: trisomy 21 (14%), trisomy 18 (9%), Turner's syndrome (4.5%) and trisomy 13 (3%). CONCLUSIONS: Prenatal genetic diagnosis allows appropriate perinatal management and contributes to prepare the patient and their families for an adverse perinatal outcome.

Impacto de la enfermedad genética en los ingresos hospitalarios en un Servicio de Pediatría / Prevalence of genetic diseases in admissions to a tertiary care hospital pediatric service

Background: With the epidemiological changes, the role of genetic factors as a cause of morbidity and mortality is increasing, changing disease patterns of patients admitted to pediatric hospitals. Aim: To describe the prevalence of genetic diseases (GD) in patients admitted to a tertiary-care hospital Pediatric Service. Material and Methods: The clinical records of consecutive admissions to a Pediatric Service of a clinical hospital in 2011 were reviewed. Two categories were assigned: with GD and without GD. Both groups were compared according to days of hospitalization, type of admission, readmissions and mortality. Results: We reviewed the 98.1% of the 1,781 total annual admissions (1,459 cases), 322 of them were readmissions (187 cases). The mean age at admission was 54.8 ± 54 months and 55% were male. The mean hospitalization length was 4.9 ± 10 days. Of total admissions and individual cases, 52.7% (938/1,781) and 48% (705/1,459) were cases with GD, respectively. Within this group, 85% (597/705) were sub-categorized as having a significant genetic base. The differences between gender, age average income and hospital mortality were not significant between the two categories. Readmissions were more common for GD than for patients without GD (Odds ratio (OR): 2.6, confidence intervals (CI): 1.9-3.6). Average hospital stay was 27% higher among GD patients (p < 0.01). Conclusions: Our findings confirm the high prevalence of GD in pediatric hospitals (52.7%), with a higher risk for readmission in cases with GD compared with those without GD.

A Deletion of More than 800 kb Is the Most Recurrent Mutation in Chilean Patients with SHOX Gene Defects.

BACKGROUND: Deletions in the SHOX gene are the most frequent genetic cause of Leri-Weill syndrome and Langer mesomelic dysplasia, which are also present in idiopathic short stature. AIM: To describe the molecular and clinical findings observed in 23 of 45 non-consanguineous Chilean patients with different phenotypes related to SHOX deficiency. METHODS: Multiplex ligation-dependent probe amplification was used to detect the deletions; the SHOX coding region and deletion-flanking areas were sequenced to identify point mutations and single-nucleotide polymorphisms (SNPs). RESULTS: The main genetic defects identified in 21 patients consisted of deletions; one of them, a large deletion of >800 kb, was found in 8 patients. Also, a smaller deletion of >350 kb was observed in 4 patients. Although we could not precisely determine the deletion breakpoint, we were able to identify a common haplotype in 7 of the 8 patients with the larger deletion based on 22 informative SNPs. CONCLUSION: These results suggest that the large deletion-bearing allele has a common ancestor and was either introduced by European immigrants or had originated in our Amerindian population. This study allowed us to identify one recurrent deletion in Chilean patients; also, it contributed to expanding our knowledge about the genetic background of our population.

Sturge-Weber syndrome: clinical and radiological correlates in 86 patients.

BACKGROUNDS AND PURPOSE: To correlate the extent of the leptomeningeal angiomatosis with clinical features in Sturge-Weber syndrome (SWS). METHODS: The study group consisted of 86 consecutive patients aged two months to 56 (mean 7.9 +/- 10.3) years with SWS and epilepsy. Clinical and MRI data were analyzed. RESULTS: Based on the extent of leptomeningeal angiomatosis, patients were divided into two subgroups: 43 patients had hemispheric angiomatosis and atrophy, whereas, another 43 had focal involvement. Nine of the 43 hemispherial patients (10%) showed bilateral involvement: all of these bilateral cases demonstrated dominance in a single side with hemispheric leptomeningeal angiomatosis and contralateral focal extension. Hemispheric and focal subgroups were clinically different. Patients with hemispheric SWS were younger at the age of epilepsy onset (p < 0.001) and age at MRI examination (p < 0.05). Neither gender, lateralization, duration of epilepsy, appearance of secondarily generalized seizures, nor seizure frequency revealed a significant difference between subgroups. CONCLUSION: Bilateral involvement is frequent and occurs in cases with a hemisperic involvement on one side. The age of epilepsy onset is related to the extent of leptomeningeal angiomatosis. Patients with hemispheric form of SWS presented with earlier age of seizure onset. Focal pial angiomatoses do not tend to progress (a longer duration is not associated with more frequent hemispheric involvement). Other variables including seizure frequency and secondary generalized tonic-clonic seizures are not associated with the extent of angiomatosis.

Dandy-Walker malformation with postaxial polydactly: a new case of Pierquin syndrome.

The combination of Dandy-Walker malformation, other central nervous system anomalies, and postaxial polydactyly has been reported previously in two pairs of siblings. We propose the name 'Pierquin syndrome' for this combination and we report a new patient with this disorder.

[Prevalence of neurological disorders among children with Down syndrome]. / Trastornos neurológicos en niños con síndrome de Down.

BACKGROUND: Neurological disturbances are common problems in children with Down Syndrome (DS). AIM: To determine the prevalence of neurological disorders affecting children with Down Syndrome. PATIENTS AND METHODS: Review of medical records of 253 children aged from 1 day to 23 years affected with DS, attended at a public hospital and a University clinic. RESULTS: The overall prevalence of neurological disorders was 38.7%. The most common problems were ocular motor disorders in 26% of cases and epilepsy in 12%. CONCLUSIONS: Neurological disorders are more common in children with DS than in the general population. Motor ocular disorders and epilepsy are the predominant disturbances detected.

Trastornos neurológicos en niños con síndrome de Down / Prevalence of neurological disorders among children with Down syndrome

Background: Neurological disturbances are common problems in children with Down Syndrome (DS). Aim: To determine the prevalence of neurological disorders affecting children with Down Syndrome. Patients and Methods: Review of medical records of253 children aged from 1 day to 23 years affected with DS, attended at a public hospital and a University clinic. Results: The overall prevalence of neurological disorders was 38.7%. The most common problems were ocular motor disorders in 26% of cases and epilepsy in 12%. Conclusions: Neurological disorders are more common in children with DS than in the general population. Motor ocular disorders and epilepsy are the predominant disturbances detected.

A new presentation of the chimeric CYP11B1/CYP11B2 gene with low prevalence of primary aldosteronism and atypical gene segregation pattern.

Familial hyperaldosteronism type I is caused by an unequal crossover of 11ß-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) genes, giving rise to a chimeric CYP11B1/CYP11B2 gene (CG). We describe a family carrying a CG with high levels of free 18-hydroxycortisol but low prevalence of primary aldosteronism (PA) and an atypical CG inheritance pattern in a family of 4 generations with 16 adults and 13 children, we measured the arterial blood pressure, serum aldosterone, and plasma renin activity and then calculated the serum aldosterone:plasma renin activity ratio and urinary free 18-hydroxycortisol. We identified the CG by long-extension PCR and predicted its inheritance pattern. The CG was found in 24 of 29 subjects (10 children and 14 adults). In CG+ patients, hypertension and high 18-hydroxycortisol were prevalent (83% and 100%, respectively). High serum aldosterone:plasma renin activity ratio was more frequent in pediatric than adult patients (80% versus 36%; P<0.001). An inverse association between serum aldosterone:plasma renin activity ratio and age was observed (r=-0.48; P=0.018). Sequence analysis identified the CYP11B1/CYP11B2 crossover in a 50-bp region spanning intron 3 of CYP11B1 and exon 4 of CYP11B2. The CG segregation differs from an autosomal disease, showing 100% of CG penetrance in generations II and III. Statistical analysis suggests that inheritance pattern was not attributed to random segregation (P<0.001). In conclusion, we describe a family with an atypical CYP11B1/CYP11B2 gene inheritance pattern and variable phenotypic expression, where the majority of pediatric patients have primary aldosteronism. Most adults have normal aldosterone and renin levels, which could mask them as essential hypertensives.