Prevalence of congenital anomalies and prenatal diagnosis by birth institution (public vs. non-public): indicators of inequality in access to elective termination of pregnancy for fetal anomalies.

Congenital anomalies (CA) encompass all morphological or functional alterations originating prenatally and present at birth. The prenatal diagnosis of these anomalies can significantly impact the overall health of the pregnant individual and may influence her decision regarding the continuation of the pregnancy. In contexts where safe pregnancy termination is not guaranteed by the state, it can lead to unsafe procedures with severe consequences. In our research, we analyzed epidemiological information on CA to develop potential indicators of inequity in access to safe abortion prior to the legalization of legal termination of pregnancy in Argentina. We included cases from 13 public hospitals and 9 non-public subsector hospitals, from the period 2013-2020. Two groups of specific CA were selected: 1) CA capable of being prenatally diagnosed, and 2) CA related to vascular disruptive events. 10/18 of the selected CA capable of being prenatally diagnosed had a significantly higher prevalence in public hospitals (anencephaly, encephalocele, spina bifida, microcephaly, hydrocephalus, holoprosencephaly, hydranencephaly, diaphragmatic hernia, gastroschisis, bilateral renal agenesis). Non public hospitals had higher prenatal detection. Birth prevalence of CA related with vascular disruptive events (limb reduction, Moebius syndrome, amniotic band sequence) were significantly higher in public hospitals. These results suggest disparities in access to prenatal diagnosis and safe abortion based on socioeconomic status. There was a significant gap in access to prenatal diagnosis for CA and possibly to safe elective abortion depending on the type of institution (public vs. non-public).

Genetic Analysis Algorithm for the Study of Patients with Multiple Congenital Anomalies and Isolated Congenital Heart Disease.

Congenital anomalies (CA) affect 3-5% of newborns, representing the second-leading cause of infant mortality in Argentina. Multiple congenital anomalies (MCA) have a prevalence of 2.26/1000 births in newborns, while congenital heart diseases (CHD) are the most frequent CA with a prevalence of 4.06/1000 births. The aim of this study was to identify the genetic causes in Argentinian patients with MCA and isolated CHD. We recruited 366 patients (172 with MCA and 194 with isolated CHD) born between June 2015 and August 2019 at public hospitals. DNA from peripheral blood was obtained from all patients, while karyotyping was performed in patients with MCA. Samples from patients presenting conotruncal CHD or DiGeorge phenotype (n = 137) were studied using MLPA. Ninety-three samples were studied by array-CGH and 18 by targeted or exome next-generation sequencing (NGS). A total of 240 patients were successfully studied using at least one technique. Cytogenetic abnormalities were observed in 13 patients, while 18 had clinically relevant imbalances detected by array-CGH. After MLPA, 26 patients presented 22q11 deletions or duplications and one presented a TBX1 gene deletion. Following NGS analysis, 12 patients presented pathogenic or likely pathogenic genetic variants, five of them, found in KAT6B, SHH, MYH11, MYH7 and EP300 genes, are novel. Using an algorithm that combines molecular techniques with clinical and genetic assessment, we determined the genetic contribution in 27.5% of the analyzed patients.

Birth prevalence of congenital anomalies in Argentina, according to socioeconomic level.

Birth prevalence of congenital anomalies (CA) in Argentina is estimated around 1.7%. CA are the second leading cause of infant mortality. Poverty and other adverse socioeconomic conditions have been associated with birth defects. To describe the prevalence at birth of CA, according to the two proxy variables of socioeconomic level: the health subsector of the hospital where the cases were born (PUB-public versus PRI-private or social security) and its geographical location. The design of the study was ecological using the data of the National Network of Congenital Anomalies of Argentina (RENAC); from October 2010 to December 2018. CA birth prevalence was estimated using the Poisson regression. We used a logistic regression model to analyze the association birth prevalence to health subsector and geographical region. A total of 2,202,994 births were examined in the study period, with a global CA prevalence of 1.69% (95% CI 1.68-1.71). The highest prevalence was observed in PUB hospitals when comparing to PRI hospitals at the country level and in all regions. There were differences in the prevalence of selected congenital anomalies with a statistically significant association to PUB (observed in anencephaly, encephalocele, hydrocephalus, microcephaly, holoprosencephaly, microtia/anotia, cleft lip and palate, postaxial polydactyly, talipes equinovarus, talipes calcaneovalgus, and gastroschisis). The prevalence of critical heart defects and chromosomal anomalies was significantly higher in PRI hospitals. Although this is an ecological study with no information on socioeconomic status at individual level, we found an association between CA frequency and selected CA with the PUB subsector. Vulnerable populations affected with CA require a greater effort from policy makers and health care providers to allocate more resources and design strategies to access to health.

Análisis de anomalías cromosómicas, desbalances genómicos y variantes de secuencia como causa de cardiopatías congénitas / Analysis of chromosomal abnormalities, genomic imbalances, and sequence variants as cause of congenital heart defects

INTRODUCCIÓN: Las cardiopatías congénitas (CC) son causadas por el desarrollo anómalo del corazón durante el período embriofetal. Abarcan un amplio espectro de anomalías estructurales de las cavidades cardíacas o de los grandes vasos, con una prevalencia mundial de 6 a 9 por 1000 nacimientos. En Argentina constituyen un tercio de las anomalías congénitas (AC) al nacimiento. Si bien su etiología es heterogénea, se ha observado recurrencia familiar acorde con la influencia de factores genéticos. El objetivo del estudio fue evaluar la presencia de anomalías cromosómicas, desbalances genómicos o variantes de secuencias en una muestra de niños afectados con CC en Argentina. MÉTODOS: Se incluyó a 289 pacientes con CC de hasta 16 años. Se realizó un cariotipo para pacientes con otras AC y análisis por amplificación múltiple de sondas dependiente de ligación (MLPA) de regiones genómicas asociadas a CC para aquellos con CC conotroncales. En muestras seleccionadas, se analizaron desbalances genómicos por microarreglos de ADN (array-CGH) o variantes de secuencia en el gen NKX2-5. RESULTADOS: Hubo 9 pacientes que presentaron anomalías cromosómicas, 21 desbalances por MLPA y 8 por array-CGH. No se hallaron variantes patogénicas en NKX2-5 en los casos estudiados. DISCUSIÓN: Se halló la causa de la afección en el 13% de los casos analizados. El estudio de pacientes con CC aisladas o asociadas a otras AC no había sido abordado previamente en Argentina mediante este algoritmo

[Zika virus embryopathy in Argentina: clinical characteristics in newborns]. / Embriopatía por virus Zika en Argentina: características clínicas y diagnóstico en recién nacidos.

Introduction: Microcephaly and brain abnormalities may be due to multiple etiologies, one of them is the congenital infection by Zika virus (ZIKV). From 2016 to the present, there has been a series of ZIKV outbreaks in Argentina. Methods: National Network of Congenital Anomalies (RENAC) and the National Institute of Viral Diseases (INEVH), under the National Administration of Laboratories and Health Institutes "Carlos Malbrán" (ANLIS), carry out the intensified surveillance of newborns with microcephaly and brain abnormalities. This article presents the clinical characteristics and laboratory testof patients detected with congenital infection by ZIKV between April 2016 to March 2018, Results: 10 cases with embryopathy were detected, six autochthonous and four imported; in two cases, the mothers were asymptomatic during pregnancy; all the cases presented microcephaly and cranial facial disproportion, ventriculomegaly in seven cases and in six cerebral calcifications. The diagnosis of congenital infection by Zika in the newborn was made by antigen-specific Immunoglobulin M (MAC-ELISA) and plaque-reduction neutralization test (PRNT90 ). PCR was negative in all cases. Conclusion: the patients presented clinical features that were consistent with those reported in other countries. The need for serological studies that allow confirmation is emphasized, ruling out cross-reactivity with other Flaviviruses.

Introducción: La microcefalia y las anomalías cerebrales congénitas pueden deberse a múltiples etiologías, siendo uno de ellas la infección congénita por el virus Zika (ZIKV). Desde 2016 hasta hoy se han sucedido una serie de brotes del ZIKV en Argentina. Métodos: La Red Nacional de Anomalías Congénitas (RENAC) y el Instituto Nacional de Enfermedades Virales (INEVH), dependientes de la Administración Nacional de Laboratorios e Institutos de Salud "Carlos Malbrán" (ANLIS), realizan la vigilancia intensificada de recién nacidos con microcefalia y anomalías cerebrales. Este trabajo presenta las características clínicas y estudios de laboratorio de los pacientes con infección congénita por ZIKV detectados entre abril de 2016 a marzo 2018. Resultados: se detectaron 10 casos con embriopatía, seis fueron autóctonos y cuatro importados; en dos casos las madres fueron asintomática durante el embarazo; todos los casos presentaron microcefalia y desproporción cráneo facial, ventriculomegalia en siete casos y en seis calcificaciones cerebrales. El diagnóstico de infección congénita por Zika en el recién nacido se realizó por estudios serológicos inmunoglobulina M antígeno específica (MAC-ELISA) y prueba de neutralización por reducción de placas (PRNT90). La PCR fue negativa en todos los casos. Conclusión: Los pacientes presentaron características clínicas coincidentes con las reportadas en otros países Se enfatiza la necesidad de estudios serológicos que permitan la confirmación, descartando la reactividad cruzada con otros Flavivirus.

Congenital limb reduction defects in 1.6 million births in Argentina.

The objectives of this study were to describe the birth prevalence of limb reduction defects (LRD) in Argentina, their clinical features, and to review the literature on this topic. The data source was the National Network of Congenital Anomalies of Argentina, a surveillance system that has been operative since 2009. Data were collected from November 1, 2009 to December 31, 2016. 1,663,610 births and 702 affected patients were registered during this period. The prevalence of LRD was 4.22/10,000 births (CI 95%: 3.93-4.54). In 15,094 stillbirths, prevalence was 30.80/10,000 (CI 95%: 22.31-40.65). Perinatal mortality (stillbirths plus early neonatal deaths) was 24.6%, mostly explained by postnatal deaths. LRD were classified according to different variables, including Gold's anatomic classification. Then, 41.0% of patients had transverse terminal defects and 50.2% had longitudinal defects. We found multiple and syndromic clinical presentation to be associated with both preaxial LRD and lethality. The prevalence of LRD was lower and perinatal mortality was higher in our study compared to that of previously published studies. Because there is heterogeneity in the inclusion and exclusion criteria among publications, a greater effort should be made in order to include similar populations and to use a unified anatomic classification and nomenclature.

Birth prevalence of congenital anomalies in the City of Buenos Aires, Argentina, according to socioeconomic level.

The goal of our study is to describe the prevalence of congenital anomalies (CA) in hospitals of the City of Buenos Aires, Argentina, according to two proxy variables of the socioeconomic level: health subsector, public (PUB) versus private/social security (PRI), and geographical location, northern (N) versus southern (S). The source of data was the National Network of Congenital Anomalies of Argentina (RENAC) (period 2010-2016). From a total of 228,208 births, 4872 newborns with CA were detected (2.14%). The prevalence in PRI-N, PUB-N, PRI-S, and PUB-S hospitals were 1.59%, 1.91%, 2.20%, and 2.43%, respectively. Prevalence of neural tube defects, abdominal wall defects, and oral clefts was significantly higher in PUB than in PRI hospitals. Prevalence of critical heart defects was significantly lower in PUB-N and in PRI-S hospitals. Prevalence of anencephaly, encephalocele, hydrocephalus, microcephaly, gastroschisis, cleft lip and palate, ductus arteriosus, and bilateral renal agenesis was higher in PUB hospitals, both N and S, as well as microphthalmia/anophthalmia and ambiguous genitalia, spina bifida, anotia/microtia, postaxial polydactyly, and diaphragmatic hernia had higher prevalences in PUB-S hospitals. Omphalocele was more frequent in PUB-N hospitals. Results suggest that vulnerable populations in the public and southern subsectors of the city still require a greater support to reinforce resources and strategies that lead to greater equity in access to health.

Prenatal detection of congenital anomalies and related factors in Argentina.

Congenital anomalies (CAs) are a leading cause of neonatal death. Many CAs can be diagnosed prenatally. To estimate the prenatal detection rate (PDR) of CA in hospitals participating in the RENAC (National Network of Congenital Anomalies of Argentina) and to analyze the PDR according to different factors. Sources were reports of RENAC from the 2013-2016 period. Congenital anomalies included were those detectable by ultrasound or by a prenatal karyotype. PDR was calculated by region, health subsector, clinical presentation, maternal age, sex, and twining. Using multiple logistic regression analysis, we evaluated predictors of prenatal detection. In total, 9976 cases were defined as prenatal detectable; 5021 were detected (PDR = 50.3%). Multiple presentation increased the chances of prenatal detection (Adj. OR = 1.6; 95%CI 1.4-1.9). Prenatal detection was lower in the public subsector (Adj. OR = 0.8; 95%CI 0.7-0.9) and in the northern regions of the country. PDR was higher than 75% in isolated cases of urinary malformation, anencephaly, and gastroschisis. Prenatal detection increased the chance of birth in higher complexity-level hospitals (Adj. OR = 2.5; 95%CI 2.3-2.8). PDR was within the range previously reported. Heterogeneity between regions and health subsector suggests the need for training to achieve equity in detection.

Acceso a la detección prenatal de anomalías fetales y a la interrupción legal del embarazo en Argentina / Access to prenatal detection of fetal anomalies and legal termination of pregnancy in Argentina

INTRODUCCIÓN El diagnóstico prenatal (DPN) de anomalías congénitas (AC) fetales permite a las personas gestantes tomar decisiones respecto a la continuidad de la gestación. En Argentina hay posiblemente una inequidad en el acceso tanto al DPN como a la interrupción el embarazo (ILE) por AC. OBJETIVO conocer el estado de situación en Argentina del DPN, el acceso a la ILE por detección de AC fetales y la disponibilidad de equipos de DPN y de ILE. MÉTODO se analizó la prevalencia al nacimiento y la tasa de detección prenatal según subsector de salud en el período 2013-2019 utilizando datos de la Red Nacional de Anomalías Congénitas (RENAC). Se relevaron los equipos de DPN e ILE a través de una encuesta estructurada realizada a profesionales de 55 instituciones durante el 2020. RESULTADOS se evaluaron 2.044.582 nacimientos. La prevalencia al nacimiento de síndromes de Down y Edwards, cardiopatías congénitas severas e hidronefrosis fue significativamente mayor en instituciones privadas. En subsector público, la prevalencia de hidranencefalia, holoprosencefalia, anencefalia, encefalocele, gastrosquisis, extrofia vesical/cloaca, microcefalia, hidrocefalia, defectos de reducción de miembro; fue significativamente mayor. La tasa de DPN fue mayor en el sector privado para 24/25 de las AC seleccionadas. De las 55 instituciones encuestadas (48 subsector público y 7 subsector privado), 32 refirieron tener equipo de DPN. El 90% de las instituciones encuestadas ofrecen ecografía de 3o trimestre con doppler a todas las personas gestantes, 51% ofrecen ecografía detallada morfológica; 44% realizan translucencia nucal, y 15% hacen pesquisa completa 1o trimestre. En 41 instituciones refirieron tener equipo de ILE y en 47 realizaron ILE por AC. DISCUSIÓN en sector privado hubo mayor DPN y menor prevalencia de ciertas AC que podrían corresponder a interrupciones electivas del embarazo. Y en el público fue menor la disponibilidad de equipos de DPN pero mayor la de equipos de ILE.

Birth prevalence of Down syndrome in Argentina. / Prevalencia del síndrome de Down al nacimiento en Argentina.

The aim of this study was to describe the prevalence at birth of Down syndrome in Argentina. The prevalence by jurisdiction and maternal age was calculated for the 2009-2015 period and the prevalence and proportion of prenatal diagnosis was compared according to sub-sector (public and private) and complexity level of the maternity wards. The association of Down syndrome with birth weight and gestational age was analyzed. The data source was the National Network of Congenital Anomalies of Argentina [Red Nacional de Anomalías Congénitas] (RENAC). The prevalence was 17.26 per 10,000 births; by jurisdictions it varied between 10.99 and 23.71; and by maternal age, between 10.32 in women <20 years of age and 158.06 in those ≥45 years of age. In hospitals of the private subsector there was a higher prevalence, attributable to differences in the structure of maternal age, and a greater proportion of prenatal diagnosis. There was a negative correlation between birth weight and Down syndrome (ß=-294.7; p<0.001). No difference in the median gestational age at birth between Down syndrome newborns and newborns without major anomalies was found, but the distribution of gestational age differed. Knowledge of certain epidemiological characteristics of this health issue could contribute to the implementation of health policies.

El objetivo de este trabajo fue describir la prevalencia al nacimiento del síndrome de Down en Argentina. Se calculó la prevalencia por jurisdicción y edad materna para el período 2009-2015 y se comparó la prevalencia y proporción del diagnóstico prenatal según subsector (público y privado) y nivel de complejidad de las maternidades. Se analizó la asociación con el peso y la edad gestacional al nacer. La fuente de datos fue la Red Nacional de Anomalías Congénitas (RENAC). La prevalencia fue de 17,26 por cada 10.000 nacimientos; por jurisdicciones varió entre 10,99 y 23,71, y por edad materna entre 10,32 en <20 años y 158,06 en ≥45 años. En hospitales del subsector privado hubo una mayor proporción de diagnóstico prenatal y una mayor prevalencia, esta última atribuible a diferencias en la estructura de edad materna. Se observó una correlación negativa entre el peso al nacer y este síndrome (ß=-294,7; p<0,001). No se evidenció diferencia en la mediana de la edad gestacional al nacer entre recién nacidos con síndrome de Down y neonatos sin anomalías mayores, pero sí en la distribución de la edad gestacional. El conocimiento de ciertas características epidemiológicas podrá contribuir a la implementación de políticas de salud.

Sistemas de vigilancia de anomalías congénitas en América Latina y el Caribe: presente y futuro

[RESUMEN]. Objetivos. Conocer la disponibilidad de los sistemas nacionales de vigilancia de anomalías congénitas en América Latina y el Caribe y describir sus características. Métodos. Estudio transversal mediante una encuesta semiestructurada y autoadministrada en línea remitida en el 2017 por las representaciones locales de la Organización Panamericana de la Salud a las autoridades de los ministerios de salud de todos los países de América Latina y el Caribe. La encuesta recabó información sobre la disponibilidad de un sistema nacional de vigilancia de anomalías congénitas en el país y sus características. Resultados. Once países cuentan con sistema nacional de vigilancia de anomalías congénitas: Argentina, Colombia, Costa Rica, Cuba, Guatemala, México, Panamá, Paraguay, República Dominicana, Uruguay y Venezuela. Los sistemas tienen características heterogéneas: 6 son sistemas de base hospitalaria; 10 incluyen en su definición de caso los nacidos vivos y los fetos muertos. En todos los sistemas de vigilancia se incluyen los casos con anomalías mayores y menores, excepto en Argentina, Colombia y Guatemala que solo registran anomalías congénitas mayores. Solo Argentina, Costa Rica y Uruguay elaboran informes periódicos que consolidan y presentan los resultados de la vigilancia; los registros de Argentina y Costa Rica disponen de manuales operativos. Conclusiones. Se comprobó la aún escasa disponibilidad de sistemas nacionales de vigilancia de anomalías congénitas en América Latina y el Caribe y su elevada heterogeneidad. Es prioritario avanzar hacia la expansión y el fortalecimiento de este tipo de vigilancia en nuestros países.

[ABSTRACT]. Objectives. To determine the availability of national systems for surveillance of birth defects in Latin America and the Caribbean and describe their characteristics. Methods. Cross-sectional study based on a semi-structured, self-administered online survey sent in 2017 by local representative offices of the Pan American Health Organization to authorities at the ministries of health of all countries in Latin America and the Caribbean. The survey obtained information on the availability and characteristics of national systems for surveillance of birth defects in each country. Results. Eleven countries have a national system for surveillance of birth defects: Argentina, Colombia, Costa Rica, Cuba, Dominican Republic, Guatemala, Mexico, Panama, Paraguay, Uruguay, and Venezuela. These systems have heterogeneous features: six are hospital-based; 10 include both live births and stillbirths in their case definition. All the surveillance systems include cases with severe and minor defects, except in Argentina, Colombia, and Guatemala, where only severe birth defects are recorded. Only Argentina, Costa Rica, and Uruguay prepare periodic reports that consolidate and present the results of surveillance. The registries in Argentina and Costa Rica have operational manuals. Conclusions. The availability of national systems for surveillance of birth defects remains limited and highly heterogeneous in Latin America and the Caribbean. Priority should be given to continued expansion and strengthening of this type of surveillance in these countries.

[RESUMO]. Objetivos. Conhecer a existência de sistemas nacionais de vigilância de anomalias congênitas na América Latina e Caribe e descrever as características destes sistemas. Métodos. Estudo transversal realizado por meio de uma pesquisa online com uso de questionário semiestruturado e autoaplicado enviado no 2017 pelas representações locais da Organização Pan-Americana da Saúde (OPAS) às autoridades dos ministérios da Saúde em todos os países da América Latina e Caribe. Foram coletados dados sobre a existência de sistema nacional de vigilância de anomalias congênitas e as características destes sistemas. Resultados. Onze países possuem um sistema nacional de vigilância de anomalias congênitas: Argentina, Colômbia, Costa Rica, Cuba, Guatemala, México, Panamá, Paraguai, República Dominicana, Uruguai e Venezuela. Os sistemas são de natureza heterogênea, seis são baseados em registros hospitalares e 10 incluem nascidos vivos e morte fetal na definição de caso. A maioria dos sistemas de vigilância abrange casos de anomalias congênitas maiores e menores, exceto na Argentina, Colômbia e Guatemala em que são registradas apenas as anomalias congênitas maiores. A Argentina, Costa Rica e Uruguai são os únicos países que apresentam relatórios periódicos reunindo os achados da vigilância e a Argentina e Costa Rica possuem manuais operacionais para o registro. Conclusões. Verificou-se que, na América Latina e no Caribe, os sistemas nacionais de vigilância de anomalias congênitas são ainda em um pequeno número e bastante heterogêneos. É uma prioridade expandir e reforçar esta forma de vigilância nos países da região.

A proposal for the systematic assessment of data quality indicators in birth defects surveillance.

BACKGROUND: Quality control and improvement are a key part of the implementation of an effective surveillance program. Data quality indicators (DQI) are key tools but have not been widely used, especially in a low-resource setting. METHODS: We developed a list of data quality indicators of birth defects surveillance. These DQI address ascertainment, description, coding, and classification. RESULTS: We developed 40 DQI that can be used widely to assess the quality of data relative to birth defects of major clinical and public health impact. CONCLUSIONS: DQI have to be both comprehensive (e.g., assess all main surveillance processes) and practical (not require sophisticated or costly data elements), so that they can be used effectively in many different settings. We propose this list of DQI for use in surveillance program as a way to document the quality of the program; detect variations within and between programs, and support quality improvements.

Application of quality indicators to data from the National Network of Congenital Anomalies of Argentina.

BACKGROUND: In Argentina, birth defects are a leading cause of infant deaths. In 2009, the National Network for Congenital Anomalies of Argentina (RENAC) was established as a hospital-based surveillance system of major structural birth defects. To assess and enhance the system's data quality, we previously developed data quality indicators (DQI). Our aim was to evaluate quality indicators in RENAC. METHODS: We applied the DQI presented in a related publication to the 2016 RENAC data. RESULTS: Among the DQI of description, spina bifida coverage and talipes had the lowest results. Regarding prevalence of hypospadias, it was lower than the defined threshold. RENAC did not achieve the ascertainment threshold of a prevalence of 21.5 per 10,000 for critical congenital heart defects. There was a high ratio of spina bifida to anencephaly. CONCLUSIONS: DQI provide a focus for improving quality, making decisions, and advocating for interventions. Examples include advocating for newborn screening of critical congenital heart defects with pulse oximetry; developing training programs for clinicians to improve the detection of isolated hypospadias; and developing visual tools and checklists to improve the completeness and accuracy of case description for spina bifida, talipes, and other major malformations. After the interventions, it is important to track the impact by measuring again the DQI.

Birth defects surveillance: experiences in Argentina and Colombia.

Birth defects (BDs) are structural or functional anomalies, sporadic or hereditary, of prenatal origin. Public health surveillance is defined as the ongoing systematic collection, analysis, and interpretation of outcome-specific data for use in the planning, implementation, and evaluation of public health practice. BD surveillance systems may have different characteristics according to design, coverage, type of surveillance, case ascertainment, case definition, BD description, maximum age of diagnosis, pregnancy outcomes, coding systems, and the location of the coding process (central or local). The aim of this article is to describe and compare methodology, applications, and results of birth defect surveillance systems in two South-American countries: Colombia and Argentina. In both countries, the surveillance systems developed activities in relation to the Zika virus emergency. For most BDs, a statistically significant higher prevalence is observed in Argentina-RENAC than in Colombian registries. This may be due to methodological reasons or real differences in prevalence. The strengths, weaknesses, and the future perspectives of the Argentine and Colombian systems are presented. When developing a surveillance system, the objectives, the available resources, and previous experiences in similar contexts must be taken into account. In that sense, the experience of Argentina and Colombia can be useful for others when developing a birth defect surveillance system.

Bone dysplasias in 1.6 million births in Argentina.

Currently accepted birth prevalence for osteochondrodysplasias (OCDs) is about 2 per 10,000 births. Our main goal is to estimate the prevalence of OCDs in Argentina and compare it with other surveillance systems. We examined 1,663,610 births among 160 hospitals of RENAC (Red Nacional de Anomalías Congénitas - National Network of Congenital Anomalies) between November 2009 and December 2016. Cases were detected and registered according to a pre-established protocol, ranked in three diagnostic evidence levels according to available clinical documentation, and categorized according to the 9th edition of the nosology and classification of genetic skeletal disorders. Within our dataset, the most frequent groups were Group-1 (FGFR3, chondrodysplasia) and Group-25 (Osteogenesis Imperfecta and decreased bone density). Birth prevalence per 10,000 for the main OCD types, were: Achondroplasia 0.47 (95% CI: 0.38-0.59), Thanatophoric Dysplasia 0.37 (95% CI: 0.29-0.48), and the Osteogenesis Imperfecta group 0.34 (95% CI: 0.26-0.44). For total OCD, birth prevalence was 2.20 per 10.000 births (95% CI: 1.98-2.44). RENAC prevalence of total OCDs was found to be lower than that reported by the Latin-American Study of Congenital Malformations (ECLAMC) and Utah Birth Defect Network but higher than EUROCAT. Our investigation is the first study of OCD prevalence in Argentina using data from every jurisdiction of the country.

Prevalencia del síndrome de Down al nacimiento en Argentina / Birth prevalence of Down syndrome in Argentina

RESUMEN El objetivo de este trabajo fue describir la prevalencia al nacimiento del síndrome de Down en Argentina. Se calculó la prevalencia por jurisdicción y edad materna para el período 2009-2015 y se comparó la prevalencia y proporción del diagnóstico prenatal según subsector (público y privado) y nivel de complejidad de las maternidades. Se analizó la asociación con el peso y la edad gestacional al nacer. La fuente de datos fue la Red Nacional de Anomalías Congénitas (RENAC). La prevalencia fue de 17,26 por cada 10.000 nacimientos; por jurisdicciones varió entre 10,99 y 23,71, y por edad materna entre 10,32 en <20 años y 158,06 en ≥45 años. En hospitales del subsector privado hubo una mayor proporción de diagnóstico prenatal y una mayor prevalencia, esta última atribuible a diferencias en la estructura de edad materna. Se observó una correlación negativa entre el peso al nacer y este síndrome ( ß=-294,7; p<0,001). No se evidenció diferencia en la mediana de la edad gestacional al nacer entre recién nacidos con síndrome de Down y neonatos sin anomalías mayores, pero sí en la distribución de la edad gestacional. El conocimiento de ciertas características epidemiológicas podrá contribuir a la implementación de políticas de salud.

ABSTRACT The aim of this study was to describe the prevalence at birth of Down syndrome in Argentina. The prevalence by jurisdiction and maternal age was calculated for the 2009-2015 period and the prevalence and proportion of prenatal diagnosis was compared according to sub-sector (public and private) and complexity level of the maternity wards. The association of Down syndrome with birth weight and gestational age was analyzed. The data source was the National Network of Congenital Anomalies of Argentina [Red Nacional de Anomalías Congénitas] (RENAC). The prevalence was 17.26 per 10,000 births; by jurisdictions it varied between 10.99 and 23.71; and by maternal age, between 10.32 in women <20 years of age and 158.06 in those ≥45 years of age. In hospitals of the private subsector there was a higher prevalence, attributable to differences in the structure of maternal age, and a greater proportion of prenatal diagnosis. There was a negative correlation between birth weight and Down syndrome ( ß=-294.7; p<0.001). No difference in the median gestational age at birth between Down syndrome newborns and newborns without major anomalies was found, but the distribution of gestational age differed. Knowledge of certain epidemiological characteristics of this health issue could contribute to the implementation of health policies.

Genetic Imbalances in Argentinean Patients with Congenital Conotruncal Heart Defects.

Congenital conotruncal heart defects (CCHD) are a subset of serious congenital heart defects (CHD) of the cardiac outflow tracts or great arteries. Its frequency is estimated in 1/1000 live births, accounting for approximately 10⁻30% of all CHD cases. Chromosomal abnormalities and copy number variants (CNVs) contribute to the disease risk in patients with syndromic and/or non-syndromic forms. Although largely studied in several populations, their frequencies are barely reported for Latin American countries. The aim of this study was to analyze chromosomal abnormalities, 22q11 deletions, and other genomic imbalances in a group of Argentinean patients with CCHD of unknown etiology. A cohort of 219 patients with isolated CCHD or associated with other major anomalies were referred from different provinces of Argentina. Cytogenetic studies, Multiplex-Ligation-Probe-Amplification (MLPA) and fluorescent in situ hybridization (FISH) analysis were performed. No cytogenetic abnormalities were found. 22q11 deletion was found in 23.5% of the patients from our cohort, 66% only had CHD with no other major anomalies. None of the patients with transposition of the great vessels (TGV) carried the 22q11 deletion. Other 4 clinically relevant CNVs were also observed: a distal low copy repeat (LCR)D-E 22q11 duplication, and 17p13.3, 4q35 and TBX1 deletions. In summary, 25.8% of CCHD patients presented imbalances associated with the disease.

[Descriptive epidemiology of major structural congenital anomalies in Argentina]. / Epidemiología descriptiva de las anomalías congénitas estructurales mayores en Argentina.

The objective of the study is to present the frequency of congenital anomalies (CA) reported to the National Network of Congenital Anomalies of Argentina (RENAC) in the year 2016, as part of its monitoring activities. RENAC is an official, national and hospital-based surveillance system of CA. The case definition includes newborns with major structural CA, external or internal, identified from birth until hospital discharge and detected by physical examination, complementary studies, interventions or autopsy. All live newborns and stillbirths of 500 grams or more were included. The prevalence of CA at birth was calculated as the quotient between the number of live newborns and stillbirths with CA, and the total number of live newborns and stillbirths, for a given period. According to their presentation, the cases with specific CA were classified into isolated, multiple and syndromes. The prevalence at birth of major structural CA was 1.59% (95% confidence intervals 1.55-1.64). The most frequent specific anomalies were: cleft lip and palate, gastroschisis, hydrocephalus, talipes equinovarus, spina bifida, postaxial polydactyly, anorectal malformation, diaphragmatic hernia, renal cysts and esophageal atresia. The most frequent syndrome was Down's. The expected annual cases and the prevalence of selected specific CA were estimated. RENAC data are within values reported in the literature.

Epidemiología descriptiva de las anomalías congénitas estructurales mayores en Argentina / Descriptive epidemiology of major structural congenital anomalies in Argentina

El objetivo del trabajo es presentar las frecuencias de anomalías congénitas (AC) estructurales mayores obtenidas por la Red Nacional de Anomalías Congénitas de Argentina (RENAC) correspondientes al año 2016, como parte de sus actividades de vigilancia de salud pública de AC. La RENAC es un sistema de vigilancia de AC oficial, nacional y de base hospitalaria. La definición de caso corresponde a recién nacidos con AC estructurales mayores, externas o internas, identificadas desde el nacimiento hasta el alta del hospital y detectadas en el examen físico, estudios complementarios, intervenciones o autopsia. Se incluyeron todos los recién nacidos vivos y los fetos muertos de 500 gramos o más. La prevalencia de AC al nacimiento se calculó como el cociente entre el número de recién nacidos vivos y fetos muertos con AC, y el número total de recién nacidos vivos y fetos muertos, en un período determinado. Según su presentación los casos con AC específicas fueron clasificados en aislados, múltiples y síndromes. La prevalencia al nacimiento de AC estructurales mayores fue de 1.59% (Intervalo de confianza del 95%: 1.55-1.64). Las anomalías específicas más frecuentes fueron: fisuras labiopalatinas, gastrosquisis, hidrocefalia, talipes equinovarus, espina bífida, polidactilia postaxial, malformación anorrectal, hernia diafragmática, quistes renales y atresia de esófago. El síndrome más frecuente fue Down. Se estimaron los casos anuales esperados y la prevalencia de AC específicas seleccionadas. En general, los datos de RENAC están dentro de los valores informados en la literatura.

The objective of the study is to present the frequency of congenital anomalies (CA) reported to the National Network of Congenital Anomalies of Argentina (RENAC) in the year 2016, as part of its monitoring activities. RENAC is an official, national and hospital-based surveillance system of CA. The case definition includes newborns with major structural CA, external or internal, identified from birth until hospital discharge and detected by physical examination, complementary studies, interventions or autopsy. All live newborns and stillbirths of 500 grams or more were included. The prevalence of CA at birth was calculated as the quotient between the number of live newborns and stillbirths with CA, and the total number of live newborns and stillbirths, for a given period. According to their presentation, the cases with specific CA were classified into isolated, multiple and syndromes. The prevalence at birth of major structural CA was 1.59% (95% confidence intervals 1.55-1.64). The most frequent specific anomalies were: cleft lip and palate, gastroschisis, hydrocephalus, talipes equinovarus, spina bifida, postaxial polydactyly, anorectal malformation, diaphragmatic hernia, renal cysts and esophageal atresia. The most frequent syndrome was Down´s. The expected annual cases and the prevalence of selected specific CA were estimated. RENAC data are within values reported in the literature.

Surveillance of microcephaly and selected brain anomalies in Argentina: Relationship with Zika virus and other congenital infections.

BACKGROUND: Zika virus (ZIKV) vertical transmission may lead to microcephaly and other congenital anomalies. In March and April 2016, the first outbreak of ZIKV occurred in Argentina. The objective was to describe the surveillance of newborns with microcephaly and other selected brain anomalies in Argentina, and evaluation different etiologies. METHODS: Participants were enrolled between April 2016 and March 2017. CASES: newborns from the National Network of Congenital Abnormalities of Argentina (RENAC) with head circumference lower than the 3rd percentile according to gestational age and sex, or selected brain anomalies. Blood and urine samples from cases and their mothers were tested for ZIKV by real-time polymerase chain reaction (RT-PCR), antigen-specific Immunoglobulin M (MAC-ELISA) and plaque-reduction neutralization test (PRNT90 ). Toxoplasmosis, rubella, herpes simplex, syphilis, and cytomegalovirus (CMV) infection were also tested. RESULTS: A total of 104 cases were reported, with a prevalence of 6.9 per 10,000 [95% confidence interval (CI): 5.7-8.4], a significant increase when compared with the data prior to 2016, Prevalence Rate Ratio 1.7 (95% CI 1.2-2.3). In five cases positive serology for ZIKV (IgM and IgG by PRNT) was detected. The five cases presented microcephaly with craniofacial disproportion. We detected four cases of CMV infection, three cases of congenital toxoplasmosis, two cases of herpes simplex infection, and one case of congenital syphilis. CONCLUSION: The prevalence of microcephaly was significantly higher when compared with the previous period. The system had the capacity to detect five cases with congenital ZIKV syndrome in a country with limited viral circulation.