Amino Acids and Acylcarnitines Reference Values for Neonatal Screening of Inborn Errors of Metabolism in Colombia by Tandem Mass Spectrometry

Abstract Neonatal screening in Colombia has been carried out since 2000. The problem that most concerns is the absence of expanded screening. To stablish reference values for amino acids and acylcarnitines, in order to provide information to guide the implementation of expanded screening. Samples collected on Whatman 903 filter paper from 10284 newborns were processed by Tandem Mass Spectrometry System (Waters - Perkin Elmer), and the NeoBase™ non-derivatized MS/MS kit (PerkinElmer), which contains controls for 11 amino acids, and 31 acylcarnitine species. For each analyte the upper limit was set above the 99th percentile, while the lower limit was set below the 1st percentile. Comparison of full-term newborn amino acid concentrations with premature ones showed no significant differences in three of them: Glycine p-0.99574, Ornithine p=0.35274, Phenylalanine p=0.13499, neither in levels of 11 of the 31 acylcarnitines. Comparison of analyte concentrations in this study with previous reports showed significant differences for all amino acids and acylcarnitines (<0.05). Experience was gained in the pre-analytic stage of expanded screening and reference values were established, for the implementation of neonatal screening program in the country.

Etiology of Microcephaly and Central Nervous System Defects during the Zika Epidemic in Colombia.

OBJECTIVE: To estimate the prevalence of microcephaly and central nervous system (CNS) defects during the Zika virus (ZIKV) epidemic in Colombia and proportion attributable to congenital ZIKV infection. STUDY DESIGN: Clinical and laboratory data for cases of microcephaly and/or CNS defects reported to national surveillance between 2015 and 2017 were reviewed and classified by a panel of clinical subject matter experts. Maternal and fetal/infant biologic specimens were tested for congenital infection and chromosomal abnormalities. Infants/fetuses with microcephaly and/or CNS defects (cases) were classified into broad etiologic categories (teratogenic, genetic, multifactorial, and unknown). Cases classified as potentially attributable to congenital ZIKV infection were stratified by strength of evidence for ZIKV etiology (strong, moderate, or limited) using a novel strategy considering birth defects unique or specific to ZIKV or other infections and laboratory evidence. RESULTS: Among 858 reported cases with sufficient information supporting a diagnosis of microcephaly or CNS defects, 503 were classified as potentially attributable to congenital ZIKV infection. Of these, the strength of evidence was considered strong in 124 (24.7%) cases; moderate in 232 (46.1%) cases; and limited in 147 (29.2%). Of the remaining, 355 (41.4%) were attributed to etiologies other than ZIKV infection (syphilis, toxoplasmosis, rubella, cytomegalovirus, herpes 1 and herpes 2 viruses only, n = 32 [3.7%]; genetic, n = 16 [1.9%]; multifactorial, n = 42 [4.9%]; unknown, n = 265 [30.9%]). CONCLUSIONS: Fifty-eight percent of cases of microcephaly and/or CNS defects were potentially attributable to congenital ZIKV infection; however, the strength of evidence varied considerably. This surveillance protocol might serve as a model approach for investigation and etiologic classification of complex congenital conditions.

Importancia de una propuesta para la implementación de un programa de tamizaje neonatal expandido en Colombia / Importance of a Proposal for Implementing an Expanded Neonatal Screening Program in Colombia / Importância de uma proposta para a implementação de um programa de triagem neonatal ampliada na colômbia

Resumen: El tamizaje neonatal expandido permite la detección temprana de diversos errores innatos del metabolismo. En Colombia, las condiciones para llevar adelante un programa nacional de alto impacto en salud pública están dadas. A través de una búsqueda bibliográfica sobre el tema en diferentes países, se realizó una disertación sobre la implementación de un programa nacional de tamizaje neonatal. Esto con el fin de plantear una propuesta de tamizaje neonatal expandido por espectrometría de masas en tándem en Colombia, completo, conciso, detallado y acorde con la legislación colombiana, las necesidades y las características de la población. Implementar un programa nacional de este tipo supone un gran impacto en la salud pública y debe ser liderado por el Estado, con la participación y apoyo de profesionales de salud, academia, asociaciones de pacientes e industria farmacéutica.

Abstract: Expanded neonatal screening allows early detection of various inborn errors of metabolism. In Colombia, the conditions to carry out a national program with a high impact on public health are in place. Through a review of the international literature on the subject, this reflection on the implementation of a national neonatal screening program brings forward a complete, concise, detailed proposal for tandem mass spectrometry-expanded neonatal screening in Colombia that conforms to the legislation and the needs and characteristics of the population. Implementing such a national program has a great impact on public health and must be led by the State, with the participation and support of health professionals, academia, patient associations, and the pharmaceutical industry.

Resumo: A triagem neonatal ampliada permite que vários erros inatos do metabolismo sejam identificados precocemente. Na Colômbia, as condições para a realização de um programa nacional com alto impacto na saúde pública estão disponíveis. Por meio de uma pesquisa bibliográfica sobre o assunto em diferentes países, foi realizada uma dissertação sobre a implementação de um programa nacional de triagem neonatal. A fim de apresentar uma proposta de triagem neonatal ampliada por espectrometria de massas em tandem na Colômbia, completa, concisa, detalhada e de acordo com a legislação colombiana, as necessidades e as características da população. A implementação de um programa nacional desse tipo tem um grande impacto na saúde pública e deve ser liderada pelo Estado, com a participação e o apoio de profissionais da saúde, da academia, das associações de pacientes e da indústria farmacêutica.

Use of High-Resolution Optical Coherence Tomography in the Surgical Management of Ocular Surface Squamous Neoplasia: A Pilot Study.

PURPOSE: To evaluate whether high-resolution optical coherence tomography (HR-OCT) can detect histologic tumor margins of ocular surface squamous neoplasia (OSSN). METHODS: Eight eyes of 8 patients with OSSN undergoing excision were studied prospectively. Immediately before surgery, the tumor was imaged using commercially available HR-OCT to identify the conjunctival margins of the neoplastic lesion. The tumor borders of the lesion determined by HR-OCT were mapped in relation to an anatomic reference point and transferred intraoperatively. The tumor was excised with 4-mm margins from the visible edge of the lesion with a "no-touch" technique. The specimens were sent for pathologic analysis and the histologic tumor margin was compared to the HR-OCT predicted tumor border. RESULTS: Mean age of the 8 patients was 67 ± 9.9 years. Seven were male, 7 were white, and, ethnically, 3 were Hispanic. All 8 tumors were bulbar and in the exposure zone. Seven tumors were limbal. Corneal extension was present in 5. Mean tumor area was 17.5 ± 11.1 mm2. Clinically, 2 of the tumors were leukoplakic, 1 papillomatous, and 3 gelatinous. A conjunctival tumor margin identified with the HR-OCT coincided with the pathologically confirmed margin mark in all eyes. CONCLUSIONS: HR-OCT has the potential to predict histologic tumor margins in OSSN. Optical identification of tumor margins could potentially decrease the incidence of residual positive margins and minimize healthy tissue removal. Advances in HR-OCT technology and integration into a microscope for "real-time" imaging are needed to further improve this technique. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Fluorescent Labeling of Proteins and Its Application to SDS-PAGE and Western Blotting.

This chapter describes very simple fluorescent methods developed in our laboratory allowing the rapid monitoring of total protein patterns on both sodium dodecyl sulfate (SDS) polyacrylamide gels and western blots. The noncovalent dye Nile red (9-diethylamino-5H-benzo[α]phenoxazine-5-one) is used for the sensitive staining of proteins in SDS gels. This method is compatible with the electroblotting of protein bands and with the staining of the resulting blot with the covalent dye MDPF (2-methoxy-2,4-diphenyl-3(2H)-furanone). These staining procedures are applied sequentially; there is no need to run a duplicate unstained gel for protein blotting. Furthermore, since only the adduct formed by the reaction of MDPF with proteins is fluorescent, there is no need to destain the membrane after protein labeling. In addition, MDPF staining is compatible with further immunodetection of specific bands with polyclonal antibodies. Finally, using the adequate conditions described below, MDPF staining does not preclude the N-terminal sequence analysis of proteins in selected bands.

Análisis de hemoglobinopatías en regiones afrocolombianas usando muestras de sangre seca de cordón umbilical / Analysis of hemoglobinopathies in afro-colombian regions using dried blood samples of umbilical cord

Introducción: las hemoglobinopatías constituyen el grupo de trastornos genéticos más frecuentes a nivel mundial, con mayor prevalencia en población negra. En Colombia hay regiones de alta densidad poblacional de afrodescendientes, lo cual plantea la necesidad de establecer estrategias para la identificación temprana de los portadores y enfermos con propósitos de prevención. Objetivo: realizar la identificación temprana de hemoglobinopatías en muestras de sangre seca de cordón umbilical. Material y métodos: para las muestras de sangre seca se utilizaron tarjetas de tamizaje neonatal rutinario de hipotiroidismo congénito. La sangre es eluida por medio de soluciones buffer acuosas y luego se aplican para separación por electroforesis en geles de isoelectroenfoque y en columna de electroforesis capilar. Resultados: de 5141 muestras recibidas de sangre seca de cordón umbilical, se descartaron 1294 por problemas de calidad, se procesaron 3847 (75%) y de éstas 3244 (84%) fueron útiles para el estudio. Se encontraron 288 (7%) con alguna variante de hemoglobina, FC (1,88%), FS(4,65%), SC(0.06%), SS(0,12%), Bart (0,18%), FC/otro (0,12%). Conclusiones: las muestras de sangre seca de cordón umbilical permiten realizar el estudio por electroforesis capilar y por isoelectroenfoque de las diferentes variantes de hemoglobinas anormales, que puede ser aplicable al diagnóstico temprano, siempre que se cumplan requisitos de calidad, en la aplicación de la muestra y en el tiempo de entrega para análisis. (Acta Med Colomb 2012: 37: 118-124).

Introduction: the hemoglobinopathies represent the most common group of genetic disorders worldwide, with higher prevalence in black population. In Colombia there are regions with high density population of African descent, which raises the need to develop strategies for early identification of carriers and patients with preventive purposes. Objective: realize early identification of hemoglobinopathies in dried blood samples from the umbilical cord. Material and methods: for the dried blood samples we used routine neonatal screening cards for congenital hypothyroidism. The blood is eluted by means of aqueous buffer solutions and then applied for separation by electrophoresis in isoelectric focusing gels and in capillary electrophoresis column. Results: of the 5141cord dried blood samples received, 1294 were discarded due to quality problems; 3847 (75%) were processed and of these, 3244 (84%) were appropriate for the study. We found 288 (7%) with some hemoglobin variant, FC (1.88%), FS (4.65%), SC (0.06%), SS (0.12%), Bart (0.18%) , FC / other (0.12%). Conclusions: dried blood samples of umbilical cord allow the study of the different variants of abnormal hemoglobins by capillary electrophoresis and isoelectric focusing, which may be applicable to an early diagnosis in the neonatal screening, provided that quality requirements in the sample application and in the delivery time for analysis are accomplished. (Acta Med Colomb 2012: 37: 118-124).

Fluorescent labeling of proteins and its application to SDS-PAGE and western blotting.

This chapter describes very simple fluorescent methods developed in our laboratory allowing the rapid monitoring of total protein patterns on both sodium dodecyl sulfate (SDS) polyacrylamide gels and western blots. The noncovalent dye Nile red (9-diethylamino-5H-benzo[alpha]phenoxazine-5-one) is used for the sensitive staining of proteins in SDS gels. This method is compatible with the electroblotting of protein bands and with the staining of the resulting blot with the covalent dye MDPF (2-methoxy-2,4-diphenyl-3(2H)-furanone). These staining procedures are applied sequentially; there is no need to run a duplicate unstained gel for protein blotting. Furthermore, since only the adduct formed by the reaction of MDPF with proteins is fluorescent, there is no need to destain the membrane after protein labeling. In addition, MDPF staining is compatible with further immunodetection of specific bands with polyclonal antibodies. Finally, using the adequate conditions described later, MDPF staining does not preclude the N-terminal sequence analysis of proteins in selected bands.

Uso del bajo peso al nacer como criterio seleccionador para la vigilancia rutinaria de anomalías congénitas de origen infeccioso / Use of low birth weight as selecting criterion for the routine surveillance of congenital anomalies of infectious origin

Introducción: La vigilancia de las anomalías congénitas cobra importancia en el contexto mundial de erradicar el síndrome de rubéola congénita. Objetivo: Identificar las anomalías congénitas y considerar el bajo peso como criterios para hacer pruebas rutinarias de IgM para el complejo TORCH. Metodología: Vigilancia de las anomalías congénitas, específicas y no específicas del síndrome de rubéola congénita (SRC) y bajo peso al nacer en diez centros hospitalarios. Se consideró como caso, todo recién nacido con alguna anomalía congénita o con bajo peso para la edad gestacional. Se practicaron pruebas en suero para rubéola, toxoplasmosis, citomegalovirus, herpes y parvovirus. Para los casos negativos se practicó cariotipo. Resultados: Se captaron 840 casos, 669 por peso bajo para la edad gestacional, 52 por anomalía no relacionada con SRC, 105 por anomalías que se podrían relacionar con el SRC. Las mßs frecuentes fueron cardiopatías, 5.1%; hepatoesplenomegalias, 3.9%; y microcefalias, 1.2%. Para sífilis congénita la tasa de positividad fue 3.7%; rubéola, 0.5%; toxoplasmosis, 1.4%; citomegalovirus, 1.5%; parvovirus, 1.2%; y herpes, 0.5%. El riesgo relativo para bajo peso con IgM rubéola positivo fue RR = 2.83 (IC: 1.26:6.36-0.95). Discusión y conclusiones: La vigilancia del SRC se hizo sobre todo por medio de la vigilancia de febriles en el primer a±o y por la presencia de algunas anomalías congénitas. La sensibilidad se mejoró por medio de la vigilancia rutinaria de anomalías congénitas, con la inclusión de bajo peso al nacer, como criterio seleccionador para estudiar los agentes infecciosos.

Introduction: Surveillance of congenital anomalies receives importance in the world-wide context of eradicating the congenital rubella syndrome. Objective: To identify the congenital anomalies and to consider the low birth weightá a criterion to test IgM for the complex TORCH. Methodology: Surveillance of the congenital specific and non specific anomalies of the congenital rubella syndrome(CRS) and low birth weight in ten hospitals. It was considered as case, everything new born with some congenital anomaly or low weight for the gestational age. Serum tests for rubella, toxoplasmosis, citomegalovirus, herpes and parvovirus were practiced. For the negative cases cariotype was performed. Results: A total of 840 cases were selected, 669 by low weight for the gestational age, 52 by anomalies not related to CRS, 52; by anomalies that could be related to the CRS, 105. The most frequent anomalies were congenital heart diseases,á 5.1%; hepatosplenomegalies, 3.9%; and microcephalies, 1.2%. There were confirmatory IgM titles for rubella in 0.5% of cases; toxoplasmosis 1.4%; citomegalovirus 1.5%; parvovirus 1.2%; herpes 0.5%; and positive test for congenital syphilis, 3.7%. In total there were 8.8% positive results for any congenital infectious disease. The relative risk for low birth weight having IgM positive rubella was RR = 2.83 (IC: 1.26:6.36-0.95). Discussion and conclusions: The surveillance for CRS, through the monitoring of febrile in the first year and by the presence of some specific congenital anomalies, could be improved in sensitivity by means of the routine monitoring of congenital anomalies, with the inclusion of low birth weight, like a selecting criterion to study the infectious agents.

[Basic standards for Colombian paternity testing laboratories, 2005]. / Estándares baisicos para los laboratorios de pruebas de paternidad en Colombia, 2005.

The Commission for Accreditation and Surveillance of Laboratories Practicing DNA Paternity Tests (created by the Colombian Law 721/2001) set up sub-commission to review the current basic Colombian standards required for paternity testing laboratories and make specific recommendations re the pertinent technical aspects in Colombia, taking ISO 17025 as current reference. This document contains such recommendations for Colombia.

Estudio inmunocitoquímico y molecular de cultivo primario de tejido molar / Immunocytochemical and molecular studies with primary cultures of molar tissue

Introducción. La enfermedad trofoblástica gestacional comprende un conjunto de patologías caracterizadas por crecimiento e invasión anómalos del trofoblasto. Las bases moleculares de esta patología son desconocidas, en parte por la dificultad para disponer de modelos biológicos adecuados. Se plantea que el sistema de factores de crecimiento similares a la insulina puede tener un papel fundamental en el desarrollo de la enfermedad. Objetivo. Caracterizar cultivos primarios de placentas de primer trimestre provenientes de pacientes con mola hidatidiforme completa y aborto espontáneo no molar mediante morfología, inmunocitoquímica y expresión diferencial de algunos genes del sistema de factores de crecimiento similares a la insulina. Materiales y métodos. Se empleó inmunocitoquímica para determinar células trofoblásticas y detección por transcripción reversa y reacción en cadena de la polimerasa de genes del sistema de factores de crecimiento similares a la insulina asociados al tipo celular. Resultados. La morfología evidenció heterogeneidad de los cultivos, incluidas células mesenquimales, trofoblásticas y de decidua. El contenido de células de trofoblasto con citoqueratina-7 (marcador específico) estuvo entre 16 y 37 por ciento. La expresión de genes corroboró la presencia de trofoblasto por medio del ARNm del factor II de crecimiento similar a la insulina, en tanto que los transcritos de la hormona de crecimiento variante evidenciaron la presencia de sincitiotrofoblasto. El factor I de crecimiento similar a la insulina y la proteína de unión tipo 1 se relacionaron con células mesenquimales y de decidua. Se observó una mayor expresión del factor II de crecimiento similar a la insulina en tejidos molares en comparación con aborto no molar. Conclusiones. Los resultados mostraron la utilidad de combinar tres metodologías, morfología, inmunocitoquímica y expresión de genes, como herramientas para la caracterización y seguimiento de cultivos placentarios a partir....

Introduction. Gestational trophoblastic disease includes a group of pathologies characterized by abnormal trophoblast growth and invasion. The molecular bases of the disease are largely unknown, due in part to the lack of appropriate biological models. The insulin-like growth factor (IGF) system plays a fundamental role in the growth and development of many tissues and is involved in the progression of several diseases. Objectives. Primary cell cultures derived from first trimester placenta were characterized from patients with complete hydatidiform mole and spontaneous non molar abortion by immunocytochemical and molecular methods. Materials and Methods. The immunocytochemical method used specific markers for trophoblastic cells, whereas RT-PCR was used to identify insulin-like growth factor gene expression. Results. Histochemical staining with hematoxilin-eosin revealed that the cultures contained heterogeneous cell types, including trophoblast and endometrial decidual cells. The ratio of trophoblast cells in the cultures varied between 16% and 37%, as detected by cytokeratine-7 as the specific trophoblast marker. Gene expression analysis corroborated the presence of trophoblasts by detecting insulin-like growth factor II mRNA, whereas GH-V transcripts were correlated with the presence of syncitiotrophoblasts. Insulin-like growth factor I and insulin-like growth factor binding protein 1 mRNAs were related to mesenchyimal and decidual cells, respectively. Higher insulin-like growth factor II expression levels were found in molar tissues in comparison with non-molar abortions. Conclusion. By combining three methodologies—morphology, immunocytochemistry and gene expression, characterization and follow-up of placenta cultures from abnormal tissues is found to facilitate diagnosis.

Estándares básicos para los laboratorios de pruebas de paternidad en Colombia, 2005 / Basic standards for Colombian paternity testing laboratories, 2005

La "Comisión de Acreditación y Vigilancia de los Laboratorios que practican las pruebas de paternidad o maternidad con marcadores genéticos de ADN", creada por la Ley 721 de 2001, constituyó una Sub-comisión para revisar las normas colombianas sobre los Estándares Básicos Requeridos en los Laboratorios de Pruebas de Paternidad, para que específicamente recomendara los aspectos técnicos pertinentes en Colombia, tomando como referente permanente la Norma ISO 17025. En este documento se consignan estas recomendaciones para Colombia.

[Immunocytochemical and molecular studies with primary cultures of molar tissue]. / Estudio inmunocitoquímico y molecular de cultivo primario de tejido molar.

INTRODUCTION: Gestational trophoblastic disease includes a group of pathologies characterized by abnormal trophoblast growth and invasion. The molecular bases of the disease are largely unknown, due in part to the lack of appropriate biological models. The insulin-like growth factor (IGF) system plays a fundamental role in the growth and development of many tissues and is involved in the progression of several diseases. OBJECTIVES: Primary cell cultures derived from first trimester placenta were characterized from patients with complete hydatidiform mole and spontaneous non molar abortion by immunocytochemical and molecular methods. MATERIALS AND METHODS: The immunocytochemical method used specific markers for trophoblastic cells, whereas RT-PCR was used to identify insulin-like growth factor gene expression. RESULTS: Histochemical staining with hematoxilin-eosin revealed that the cultures contained heterogeneous cell types, including trophoblast and endometrial decidual cells. The ratio of trophoblast cells in the cultures varied between 16% and 37%, as detected by cytokeratine-7 as the specific trophoblast marker. Gene expression analysis corroborated the presence of trophoblasts by detecting insulin-like growth factor II mRNA, whereas GH-V transcripts were correlated with the presence of syncitiotrophoblasts. Insulin-like growth factor I and insulin-like growth factor binding protein 1 mRNAs were related to mesenchyimal and decidual cells, respectively. Higher insulin-like growth factor II expression levels were found in molar tissues in comparison with non-molar abortions. CONCLUSION: By combining three methodologies-morphology, immunocytochemistry and gene expression, characterization and follow-up of placenta cultures from abnormal tissues is found to facilitate diagnosis.

Incomplete surveillance of a dengue-2 epidemic in Ibagué, Colombia, 1995-1997.

From April 1995 through November 1997 a dengue epidemic occurred in Ibagué (400,000 population), Colombia, where 3,419 cases were reported and DEN 2 virus was isolated from seven patients. A sero-survey conducted in 1996 found evidence of previous dengue infection in 9.6% of the population, indicating that many infections had not been reported. The dengue infections occurred in all age groups, but children under five years of age were most frequently infected. Forty-five percent of this Ibagué population were born after the re-appearance of dengue in Colombia in 1972, but have never been infected with dengue virus. Most of the cases reported as dengue hemorrhagic fever did not fulfill the current case definition. Aedes aegypti larvae were found in 19% of dwellings surveyed, most often in uncovered low tanks used for water storage. Many residents were not acquainted with the domestic nature of the mosquito vector. Health workers attributed the failure of the dengue control programs to lack of leadership and other administrative problems.

[Polymorphisms of APO-E in Colombian women with osteoporosis: correlation with clinical and social risk variables]. / Análisis de polimorfismos APO-E en mujeres colombianas con osteoporosis y correlación con variables clínicas y sociales de riesgo.

Several studies have reported an association between apolipoprotein E polymorphisms and osteoporosis, specially the genotype APO-E4. In order to analyze the APO-E polymorphisms and to identify their association with clinical and social variables, a descriptive study was undertaken that included 32 women with osteoporosis, from different regions of Colombia. The polymorphisms were detected by PCR and RFLP methods. In osteopenia and osteoporosis combined with osteopenia were observed the genotype epsilon3/epsilon3 in the 84% (n=27), and 16% (epsilon3/epsilon4=12.5%, n=4; epsilon4/epsilon4=3.1%, n=1) for the genotypes bearing the epsilon4 allele. The same tendency was observed by age of the menopause, epsilon3/epsilon3 in the 83% (n=25), and the genotypes bearing the epsilon4 allele in the 17% (n=5) (epsilon3/epsilon4=13.3%, n=4; epsilon4/epsilon4=3.3%, n=1). No association of APO-E4 was detected with socioeconomic stratum, fracture, illness, surgeries, and milk consumption. No significant differences were observed in the bone mineral density (BMD) of the lumbar column between the genotypes with or without the epsilon4 allele epsilon4+/- (epsilon3/epsilon4 0.96+/-0.14 g/cm2); epsilon4+/+ (epsilon4/epsilon4 0.87+/-0.0 g/cm2); epsilon4-/- (epsilon3/epsilon3 0.86+/-0.16 g/cm2); p=0.49, and femoral bone mineral density epsilon4+/- (epsilon3/epsilon4 0.84+/-0.03 g/cm2); epsilon4+/+ (epsilon4/epsilon4 0.84+/-0.0 g/cm2); epsilon4-/- (epsilon3/epsilon3 0.74+/-0.01 g/cm2); p=0.014. However, when exploring the differences of BMD in the femoral neck, a significant difference was observed (t=4.17, p=0.05). These results confirm epsilon4 allele frequencies similar to those reported for caucasian and Japanese, subjects. Larger studies are necessary to elucidate the effect of APO-E in bone marrow and the dose-effect relation.

Incomplete surveillance of a Dengue-2 epidemic in Ibagué, Colombia, 1995-1997 / Vigilancia epidemiológica incompleta de la epidemia de dengue-2 en Ibagué, Colombia, 1995-1997

From April 1995 through November 1997 a dengue epidemic occurred in Ibagué (400,000 population), Colombia, where 3,419 cases were reported and DEN 2 virus was isolated from seven patients. A sero-survey conducted in 1996 found evidence of previous dengue infection in 9.6% of the population, indicating that many infections had not been reported. The dengue infections occurred in all age groups, but children under five years of age were most frequently infected. Forty-five percent of this Ibagué population were born after the re-appearance of dengue in Colombia in 1972, but have never been infected with dengue virus. Most of the cases reported as dengue hemorrhagic fever did not fulfill the current case definition. Aedes aegypti larvae were found in 19% of dwellings surveyed, most often in uncovered low tanks used for water storage. Many residents were not acquainted with the domestic nature of the mosquito vector. Health workers attributed the failure of the dengue control programs to lack of leadership and other administrative problems.

Desde abril de 1995 a noviembre de 1997 ocurrió una epidemia de dengue en Ibagué, Tolima (400.000 habitantes), Colombia, en la cual se notificaron 3.419 casos y se aisló virus dengue 2 en el suero de 7 pacientes. En una encuesta serológica realizada en 1996 se encontró evidencia de infección anterior por dengue en 9,6% de la población, lo cual indica que muchas infecciones no se habían reportado. Las infecciones recientes del dengue ocurrieron en todos los grupos de edad, pero los niños menores de cinco años fueron más frecuentemente infectados. 45% de éstos, que nacieron después de la reemergencia del dengue en Colombia en 1972, nunca habían sido infectados con virus del dengue. La mayoría de los casos notificados de dengue hemorrágico no satisfacían la definición actual de caso. En el estudio entomológico se encontraron larvas en el 19% de las viviendas examinadas, la mayoría de las veces de Aedes aegypti en albercas destapadas, donde muchos residentes no entendían la naturaleza doméstica del mosquito vector. El personal de salud fue entrevistado y atribuyeron la falla de los programas de control del dengue a la carencia de dirección y a otros problemas administrativos.

Análisis de polimorfismos APO-E en mujeres colombianas con osteoporosis y correlación con variables clínicas y sociales de riesgo / Polymorphismsof APO-E in Colombian women with osteoporosis: correlation among clinical and s9ocial risk variables

Varios estudios han demostrado la asociación de los polimorfismos de la apolipoproteína E (APO-E) con la osteoporosis, especialmente, la APO-E 4. Para analizar los polimorfismos APOE e identificar la asociación con variables clínicas y sociales, se realizó un estudio descriptivo de 32 mujeres con osteoporosis, provenientes de diferentes regiones de Colombia, mediante metodologías PCR y RFLP. Se observaron en osteoporosis, osteopenia y osteoporosis combinada con osteopenia frecuencias para el genotipo épsilon3/épsilon3 en el 84,3% (n=27), y en el 15,6% para los genotipos con el alelo épsilon4 (épsilon3/épsilon4=12,5%, n=4; épsilon4/épsilon4=3,1%, n=1); la misma tendencia se observó en la distribución por edad de la menopausia, épsilon3/épsilon3 en el 83,3% (n=25), y genotipos con el alelo épsilon4 en el 16,6% (n=5) (épsilon3/épsilon4=13,3%, n=4; épsilon4/épsilon4=3,3%, n=1). No hubo asociación de APO-E4 con estrato socioeconómico, fracturas, enfermedades o consumo de lácteos. Aunque no hubo efecto del alelo épsilon4 en la densidad mineral ósea (DMO) de la columna lumbar: épsilon4+/-(épsilon3/épsilon4 0,960±0,144 g/cm2); épsilon4+/+ (épsilon4/épsilon4 0,873±0,00 g/cm2); épsilon4-/- (épsilon3/épsilon3 0,858±0,160 g/cm2); p=0,49, ni en cuello femoral: épsilon4+/-(épsilon3/épsilon4 0,841±0,026 g/cm2); épsilon4+/+ (épsilon4/épsilon4 0,842±0,00 g/cm2); épsilon4- /- (épsilon3/épsilon3 0,735±0,013 g/cm2), p=0,14, al explorar las diferencias de medias de DMO en el cuello femoral, se observó una diferencia significativa, t=4,17 p=0,05. Estos datos confirman una frecuencia del alelo épsilon4 similar a lo reportado en poblaciones caucásicas y japonesas; se sugiere realizar estudios a gran escala para esclarecer el impacto de la APO-E sobre la DMO y su relación dosis-efecto.

Several studies have reported an association between apolipoprotein E polymorphisms and osteoporosis, specially the genotype APO-E4. In order to analyze the APO-E polymorphisms and to identify their association with clinical and social variables, a descriptive study was undertaken that included 32 women with osteoporosis, from different regions of Colombia. The polymorphisms were detected by PCR and RFLP methods. In osteopenia and osteoporosis combined with osteopenia were observed the genotype epsilon3/epsilon3 in the 84% (n=27), and 16% (epsilon3/epsilon4=12,5%, n=4; epsilon4/epsilon4=3,1%, n=1) for the genotypes bearing the epsilon4 allele. The same tendency was observed by age of the menopause,epsilon3/epsilon3 in the 83% (n=25), and the genotypes bearing the epsilon4 allele in the 17% (n=5)(epsilon3/epsilon4=13,3%, n=4; epsilon4/epsilon4=3,3%, n=1). No association of APO-E4 was detected with socioeconomic stratum, fracture, illness, surgeries, and milk consumption. No significant differences were observed in the bone mineral density (BMD) of the lumbar column between the genotypes with or without the epsilon4 allele epsilon4+/- (epsilon3/epsilon4 0.96±0.14 g/cm2); epsilon4+/+ (epsilon4/epsilon4 0.87±0.0 g/cm2); epsilon4-/- (epsilon3/epsilon3 0.86±0.16 g/cm2); p=0.49, and femoral bone mineral density epsilon4+/- (epsilon3/epsilon4 0.84±0.03 g/cm2); epsilon4+/+ (epsilon4/epsilon4 0.84±0.0 g/cm2); epsilon4-/- (epsilon3/epsilon3 0.74±0.01 g/cm2); p=0.014. However, when exploring the differences of BMD in the femoral neck, a significant difference was observed (t=4.17, p=0.05). These results confirm epsilon4 allele frequencies similar to those reported for caucasian and Japanese, subjects. Larger studies are necessary to elucidate the effect of APO-E in bone marrow and the dose-effect relation.

Estimación de Vitamina D en mujeres con osteopenia y osteoporosis en Cundinamarca-Colombia, por medio de extracción en fase sólida, cromatografía líquida de alta resolución y análisis multivariado / Vitamin D estimate in women with osteopenia and osteoporosis in Cundinamarca, Colombia, by means of extraction in solid phase, liquid chromatography of high resolution and multivaried analysis

Actualmente existe gran interés en el metabolismo mineral y el papel de la vitamina D3 por su importancia en el entendimiento de la patogénesis de la osteoporosis y, en consecuencia, por sus aplicaciones terapéuticas y preventivas. La cuantificación de la Vitamina D implica varios pasos previos: separación, extracción y fraccionamiento, que requieren el desarrollo de diversos métodos buscando exactitud, precisión, rapidez y versatilidad. El presente estudio tuvo como objetivo cuantificar las concentraciones séricas de los principales metabolitos de la vitamina D3: 24-hidroxicolecalciferol, 24,25-dihidroxicolecalciferol y 1,25 dihidroxicolecalciferol expresados como vitamina D3 total en 50 pacientes con osteopenia u osteoporosis. El ensayo se realizó por un sistema de HPLC. La recuperabilidad post-extracción fue del 85 porciento, la sensibilidad para el 1,25 dihidroxicolecalciferol fue de 12.37 pg/ml y del colecalciferol de 25 pg/ml. El promedio de Vitamina D3 total fue de 2072 ng/ml con un intervalo de 6.3 a 10600 ng/ml y se halló diferencia significativa en las medias de concentración de Vitamina D entre mujeres con DMO normal y las que tenían al menos osteopenia en cadera (p<0.04); sin embargo, esta diferencia no fue significativa en pacientes en columna. Se encontró una diferencia significativa de concentraciones medias de vitamina D entre casos con y sin antecedente de fractura (p=0.12). Se discute la relación de las concentraciones de vitamina D con los valores de densidad mineral ósea y variables clínicas, biológicas y sociodemográficas

Disminución de la incidencia de defectos de cierre del tubo neural en el hospital Universitario de Neiva: posible efecto de la promoción del consumo de ácido fólico / Low incidence of congenital neural tube efects at the Neiva University Hospital: possible effect of folic acid supplementation

Los defectos del tubo neural (DTN) son defectos de nacimiento, del cerebro o la médula espinal, los cuales llevan a la muerte o a la discapacidad. Las causas de los DTN son desconocidas. Se piensa que ocurren por una interacción de factores genéticos y ambientales. En 1997, se observó un significativo aumento en la incidencia de defectos del tubo neural en el Hospital Universitario de Neiva (p=0,035), respecto al año anterior. El primer esfuerzo de control consistió en promover el consumo de ácido fólico siguiendo las recomendaciones universales de suplementación y fortificación (CDC Folic Acid Resource Guide) En este estudio se evaluó la incidencia de los DTN durante 1998, como posible indicador del impacto de las medidas tomadas. Se identificaron los nacidos DTN, los nacidos con síndrome de Down o con labio o paladar hendido, la proporción de abortos y la de nacidos muertos. La tasa de DTN disminuyó en forma significativa (p=0,024) respecto a 1997 y su diferencia con la tasa de Latinomérica no fue significativa (p=0,526). Se concluyó que la incidencia fue menor 1998 y regresó a la tasa esperada para la región. Aunque se desconoce la causa del descenso, es posible que sea el resultado de la divulgación de los beneficios de una buena nutrición materna, la suplementación progestacional con ácido fólico, la fortificación de la harina de trigo, o una sumatoria de todas las medidas. Se recomienda desarrollar un estudio de actitudes y prácticas sobre el uso de ácido fólico en la población de mujeres de Neiva en edad fértil y establecer un protocolo de vigilancia activada de los DTN

Diagnóstico prenatal citogenético: líquido amniótico versus vellosidades coriónicas

Se presentan los resultados comparativos de un estudio prenatal citogenético en muestras de líquido amniótico (LA) y vellosidades coriónicas(VC). Se evaluaron 47 LA obtenidos durante el segundo trimestre de gestación y 25 VC del primer trimestre, de pacientes remitidas al Instituto Nacional de Salud cuyas gestaciones se encontraban con riesgo incrementado de presentar anomalías cromosómicas. Con las muestras de LA se realizaron cultivos largos combinando los métodos en frasco y en slide flask. Con las VC se utilizó el método de cultivo corto durante 24 y 48 horas. Se realizaron las bandas cromosómicas GTG y QFQ. El éxito citogenético obtenido fue alto tanto para las muestras de LA como para las de VC. El tipo de alteraciones cromosómicas encontradas fue el esperado para la población estudiada pero la frecuencia fue más alta que la reportada en la literatura(truncado 2500 caracteres)

Estudios moleculares en pacientes colombianos con Fibrosis quística

La fibrosis quística (FQ), la enfermedad autosómica recesiva más frecuente en poblaciones caucásicas, tiene una incidencia promedio de 1/2.500 recién nacidos