Prevalencia de osteopenia del prematuro antes y después de la implementación de una estrategia temprana de manejo fosfocálcico / Prevalence of osteopenia of prematurity before and after implementing an early strategy with the use of calcium and phosphate

Introducción. Con el uso de la nutrición parenteral agresiva en recién nacidos de muy bajo peso, se detectaron alteraciones del metabolismo fosfocálcico. En 2016 se implementó una estrategia de prevención a través del monitoreo fosfocálcico y su suplementación temprana. El objetivo fue estudiar si esta estrategia disminuye la prevalencia de osteopenia e identificar factores de riesgo asociados. Población y métodos. Estudio cuasiexperimental que comparó la prevalencia de osteopenia entre dos grupos: uno después de implementar la estrategia de monitoreo y suplementación fosfocálcica (01/01/2017-31/12/2019), y otro previo a dicha intervención (01/01/2013-31/12/2015). Resultados. Se incluyeron 226 pacientes: 133 pertenecen al período preintervención y 93 al posintervención. La prevalencia de osteopenia global fue del 26,1 % (IC95% 20,5-32,3) y disminuyó del 29,3 % (IC95% 21,7-37,8) en el período preintervención al 21,5 % (IC95% 13,6-31,2) en el posintervención, sin significancia estadística (p = 0,19). En el análisis multivariado, el puntaje NEOCOSUR de riesgo de muerte al nacer, recibir corticoides posnatales y el período de intervención se asociaron de manera independiente a osteopenia. Haber nacido luego de la intervención disminuyó un 71 % la probabilidad de presentar fosfatasa alcalina >500 UI/L independientemente de las restantes variables incluidas en el modelo. Conclusión. La monitorización y suplementación fosfocálcica precoz constituye un factor protector para el desarrollo de osteopenia en recién nacidos con muy bajo peso al nacer.

Introduction. With the use of aggressive parenteral nutrition in very low birth weight infants, alterations in calcium and phosphate metabolism were detected. In 2016, a prevention strategy was implemented through calcium phosphate monitoring and early supplementation. Our objective was to study whether this strategy reduces the prevalence of osteopenia and to identify associated risk factors. Population and methods. Quasi-experiment comparing the prevalence of osteopenia between two groups: one after implementing the calcium phosphate monitoring and supplementation strategy (01/01/2017­12/31/2019) and another prior to such intervention (01/01/2013­12/31/2015). Results. A total of 226 patients were included: 133 in the pre-intervention period and 93 in the post-intervention period. The overall prevalence of osteopenia was 26.1% (95% CI: 20.5­32.3) and it was reduced from 29.3% (95% CI: 21.7­37.8) in the pre-intervention period to 21.5% (95% CI: 13.6­31.2) in the post-intervention period, with no statistical significance (p = 0.19). In the multivariate analysis, the NEOCOSUR score for risk of death at birth, use of postnatal corticosteroids, and the intervention period were independently associated with osteopenia. Being born after the intervention reduced the probability of alkaline phosphatase > 500 IU/L by 71%, regardless of the other variables included in the model. Conclusion. Calcium phosphate monitoring and early supplementation is a protective factor against the development of osteopenia in very low birth weight infants.

Prevalence of osteopenia of prematurity before and after implementing an early strategy with the use of calcium and phosphate. / Prevalencia de osteopenia del prematuro antes y después de la implementación de una estrategia temprana de manejo fosfocálcico.

Introduction. With the use of aggressive parenteral nutrition in very low birth weight infants, alterations in calcium and phosphate metabolism were detected. In 2016, a prevention strategy was implemented through calcium phosphate monitoring and early supplementation. Our objective was to study whether this strategy reduces the prevalence of osteopenia and to identify associated risk factors. Population and methods. Quasi-experiment comparing the prevalence of osteopenia between two groups: one after implementing the calcium phosphate monitoring and supplementation strategy (01/01/2017-12/31/2019) and another prior to such intervention (01/01/2013-12/31/2015). Results. A total of 226 patients were included: 133 in the pre-intervention period and 93 in the post-intervention period. The overall prevalence of osteopenia was 26.1% (95% CI: 20.5-32.3) and it was reduced from 29.3% (95% CI: 21.7-37.8) in the pre-intervention period to 21.5% (95% CI: 13.6-31.2) in the post-intervention period, with no statistical significance (p = 0.19). In the multivariate analysis, the NEOCOSUR score for risk of death at birth, use of postnatal corticosteroids, and the intervention period were independently associated with osteopenia. Being born after the intervention reduced the probability of alkaline phosphatase > 500 IU/L by 71%, regardless of the other variables included in the model. Conclusion. Calcium phosphate monitoring and early supplementation is a protective factor against the development of osteopenia in very low birth weight infants.

Introducción. Con el uso de la nutrición parenteral agresiva en recién nacidos de muy bajo peso, se detectaron alteraciones del metabolismo fosfocálcico. En 2016 se implementó una estrategia de prevención a través del monitoreo fosfocálcico y su suplementación temprana. El objetivo fue estudiar si esta estrategia disminuye la prevalencia de osteopenia e identificar factores de riesgo asociados. Población y métodos. Estudio cuasiexperimental que comparó la prevalencia de osteopenia entre dos grupos: uno después de implementar la estrategia de monitoreo y suplementación fosfocálcica (01/01/2017-31/12/2019), y otro previo a dicha intervención (01/01/2013-31/12/2015). Resultados. Se incluyeron 226 pacientes: 133 pertenecen al período preintervención y 93 al posintervención. La prevalencia de osteopenia global fue del 26,1 % (IC95% 20,5-32,3) y disminuyó del 29,3 % (IC95% 21,7-37,8) en el período preintervención al 21,5 % (IC95% 13,6-31,2) en el posintervención, sin significancia estadística (p = 0,19). En el análisis multivariado, el puntaje NEOCOSUR de riesgo de muerte al nacer, recibir corticoides posnatales y el período de intervención se asociaron de manera independiente a osteopenia. Haber nacido luego de la intervención disminuyó un 71 % la probabilidad de presentar fosfatasa alcalina >500 UI/L independientemente de las restantes variables incluidas en el modelo. Conclusión. La monitorización y suplementación fosfocálcica precoz constituye un factor protector para el desarrollo de osteopenia en recién nacidos con muy bajo peso al nacer.

Hipoglucemia neonatal en hijos de madres con diabetes mellitus gestacional. Comparación de la incidencia según el tratamiento materno / Neonatal hypoglycemia in infants born to mothers with gestational diabetes mellitus. Comparison of its incidence based on maternal treatment

Introducción. La hipoglucemia neonatal es una complicación de la diabetes mellitus gestacional Son pocos los estudios que avalan la pesquisa sistemática en este grupo poblacional durante las primeras horas de vida. Objetivos. Evaluar la asociación entre tratamiento materno recibido (dieta versus insulina) y el desarrollo de hipoglucemia, e identificar los factores de riesgo asociados. Población y métodos. Estudio observacional, analítico y retrospectivo realizado en en las sedes de Buenos AIres y San Justo de un hospital general de tercer nivel entre el 1 de enero de 2017 y el 31 de diciembre de 2018. Se estimó la incidencia de hipoglucemia (≤47 mg/dl) en recién nacidos según el manejo de la diabetes materna y se realizó un análisis multivariable para evaluar factores asociados. Resultados. Se incluyeron 195 pacientes. No se encontró diferencia estadística en la incidencia de hipoglucemia según el tratamiento materno recibido (45,3 % versus 39,7 %; p = 0,45) ni se identificaron factores de riesgo asociados. Modificando el valor de corte a ≤40 mg/dl, tampoco se encontraron diferencias en la incidencia (23,4 % versus 19 %, p = 0,48); no obstante, los pacientes hipoglucémicos presentaron un hematocrito significativamente mayor y una menor prevalencia de lactancia exclusiva al egreso. El análisis multivariable mostró una asociación independiente entre alto peso al nacer con hipoglucemia que requiere corrección. Conclusiones. La incidencia de hipoglucemia neonatal en la población estudiada no presentó diferencia según el tratamiento materno recibido. El estudio realizado fundamenta el control de la glucemia en estos niños en la práctica diaria.

Introduction. Neonatal hypoglycemia is a complication of gestational diabetes mellitus. Few studies have been conducted to support a systematic screening in the first hours of life of this population group. Objectives. To assess the association between the treatment administered to the mother (diet vs. insulin) and the development of hypoglycemia, and to identify associated risk factors. Population and methods. Observational, analytical, and retrospective study carried out at the Buenos Aires and San Justo maternal centers of a general, tertiary care hospital between 01-01-2017 and 12-31-2018. The incidence of neonatal hypoglycemia (≤ 47 mg/dL) based on the management of maternal diabetes was estimated and a multivariate analysis was done to assess related factors. Results. A total of 195 patients were included. No statistical difference was found in the incidence of hypoglycemia based on the treatment administered to the mother (45.3% vs. 39.7%; p = 0.45) and no associated risk factors were identified. Once the cutoff point was changed to ≤ 40 mg/dL, no differences were found in the incidence either (23.4% versus 19%, p = 0.48); however, patients with hypoglycemia had a significantly higher hematocrit level and a lower prevalence of exclusive breastfeeding upon discharge. Multivariate analysis showed an independent association between a high birth weight and hypoglycemia, requiring correction. Conclusions. The incidence of neonatal hypoglycemia in the studied population did not vary based on the treatment received by the mother. This study supports the control of glycemia in these infants in daily practice.

Neonatal hypoglycemia in infants born to mothers with gestational diabetes mellitus. Comparison of its incidence based on maternal treatment. / Hipoglucemia neonatal en hijos de madres con diabetes mellitus gestacional. Comparación de la incidencia según el tratamiento materno.

INTRODUCTION: Neonatal hypoglycemia is a complication of gestational diabetes mellitus. Few studies have been conducted to support a systematic screening in the first hours of life of this population group. OBJECTIVE: To assess the association between the treatment administered to the mother (diet vs. insulin) and the development of hypoglycemia, and to identify associated risk factors. MATERIAL AND METHODS: Observational, analytical, and retrospective study carried out at the Buenos Aires and San Justo maternal centers of a general, tertiary care hospital between 01-01-2017 and 12-31-2018. The incidence of neonatal hypoglycemia (≤ 47 mg/dL) based on the management of maternal diabetes was estimated and a multivariate analysis was done to assess related factors. RESULTS: A total of 195patients were included. No statistical difference was found in the incidence of hypoglycemia based on the treatment administered to the mother (45.3% vs. 39.7%; p = 0.45) and no associated risk factors were identified. Once the cutoff point was changed to ≤ 40 mg/dL, no differences were found in the incidence either (23.4% versus 19%, p = 0.48); however, patients with hypoglycemia had a significantly higher hematocrit level and a lower prevalence of exclusive breastfeeding upon discharge. Multivariate analysis showed an independent association between a high birth weight and hypoglycemia, requiring correction. CONCLUSIONS: The incidence of neonatal hypoglycemia in the studied population did not vary based on the treatment received by the mother. This study supports the control of glycemia in these infants in daily practice.

Introducción. La hipoglucemia neonatal es una complicación de la diabetes mellitus gestacional. Son pocos los estudios que avalan la pesquisa sistemática en este grupo poblacional durante las primeras horas de vida. OBJETIVOS: Evaluar la asociación entre tratamiento materno recibido (dieta versus insulina) y el desarrollo de hipoglucemia, e identificar los factores de riesgo asociados. Población y métodos. Estudio observacional, analítico y retrospectivo realizado en en las sedes de Buenos AIres y San Justo de un hospital general de tercer nivel entre el 1 de enero de 2017 y el 31 de diciembre de 2018. Se estimó la incidencia de hipoglucemia (≤47 mg/dl) en recién nacidos según el manejo de la diabetes materna y se realizó un análisis multivariable para evaluar factores asociados. RESULTADOS: Se incluyeron 195 pacientes. No se encontró diferencia estadística en la incidencia de hipoglucemia según el tratamiento materno recibido (45,3 % versus 39,7 %; p = 0,45) ni se identificaron factores de riesgo asociados. Modificando el valor de corte a ≤40 mg/ dl, tampoco se encontraron diferencias en la incidencia (23,4 % versus 19 %, p = 0,48); no obstante, los pacientes hipoglucémicos presentaron un hematocrito significativamente mayor y una menor prevalencia de lactancia exclusiva al egreso. El análisis multivariable mostró una asociación independiente entre alto peso al nacer con hipoglucemia que requiere corrección. CONCLUSIONES: La incidencia de hipoglucemia neonatal en la población estudiada no presentó diferencia según el tratamiento materno recibido. El estudio realizado fundamenta el control de la glucemia en estos niños en la práctica diaria.

Presentación atípica de un neuroblastoma congénito metastásico con efecto renal grave: informe de caso / Atypical presentation of a congenital metastatic neuroblastoma with severe renal impact: case report

El neuroblastoma es un tumor derivado de la cresta neural. Se trata del tumor maligno más frecuente en recién nacidos y existe una amplia variabilidad en su forma de presentación. En algunos casos, el diagnóstico se realiza mediante un hallazgo ecográfico, mientras que en otros se manifiesta como enfermedad metastásica agresiva. Se presenta el caso de una paciente prematura con diagnóstico posnatal de neuroblastoma congénito metastásico con manifestaciones clínicas graves y evolución atípica. Asimismo, se destaca una lesión renal grave que requirió terapia dialítica.

Neuroblastoma is a neural crest-derived tumor and the most common malignant tumor in neonates. Its clinical presentation can be quite variable. In some cases, it presents as an aggressive metastatic disease whilst in others it is a finding in scans performed for other reasons. The following report presents the case of a premature newborn, diagnosed postnatally with metastatic congenital neuroblastoma, with an atypical and torpid course, including severe renal injury and dialysis requirement.

[Atypical presentation of a congenital metastatic neuroblastoma with severe renal impact: case report]. / Presentación atípica de un neuroblastoma congénito metastásico con efecto renal grave: informe de caso.

Neuroblastoma is a neural crest-derived tumor and the most common malignant tumor in neonates. Its clinical presentation can be quite variable. In some cases, it presents as an aggressive metastatic disease whilst in others it is a finding in scans performed for other reasons. The following report presents the case of a premature newborn, diagnosed postnatally with metastatic congenital neuroblastoma, with an atypical and torpid course, including severe renal injury and dialysis requirement.

El neuroblastoma es un tumor derivado de la cresta neural. Se trata del tumor maligno más frecuente en recién nacidos y existe una amplia variabilidad en su forma de presentación. En algunos casos, el diagnóstico se realiza mediante un hallazgo ecográfico, mientras que en otros se manifiesta como enfermedad metastásica agresiva. Se presenta el caso de una paciente prematura con diagnóstico posnatal de neuroblastoma congénito metastásico con manifestaciones clínicas graves y evolución atípica. Asimismo, se destaca una lesión renal grave que requirió terapia dialítica.

Isolate-Dependent Differences in Clinical, Pathological, and Transcriptional Profiles following In Vitro and In Vivo Infections with Rickettsia rickettsii.

Rickettsia rickettsii, the etiological agent of Rocky Mountain spotted fever (RMSF), a life-threatening tick-borne disease that affects humans and various animal species, has been recognized in medicine and science for more than 100 years. Isolate-dependent differences in virulence of R. rickettsii have been documented for many decades; nonetheless, the specific genetic and phenotypic factors responsible for these differences have not been characterized. Using in vivo and in vitro methods, we identified multiple phenotypic differences among six geographically distinct isolates of R. rickettsii, representing isolates from the United States, Costa Rica, and Brazil. Aggregate phenotypic data, derived from growth in Vero E6 cells and from clinical and pathological characteristics following infection of male guinea pigs (Cavia porcellus), allowed separation of these isolates into three categories: nonvirulent (Iowa), mildly virulent (Sawtooth and Gila), and highly virulent (Sheila SmithT, Costa Rica, and Taiaçu). Transcriptional profiles of 11 recognized or putative virulence factors confirmed the isolate-dependent differences between mildly and highly virulent isolates. These data corroborate previous qualitative assessments of strain virulence and suggest further that a critical and previously underappreciated balance between bacterial growth and host immune response could leverage strain pathogenicity. Also, this work provides insight into isolate-specific microbiological factors that contribute to the outcome of RMSF and confirms the hypothesis that distinct rickettsial isolates also differ phenotypically, which could influence the severity of disease in vertebrate hosts.

A tick cell line as a powerful tool to screen the antimicrobial susceptibility of the tick-borne pathogen Anaplasma marginale.

Anaplasma marginale is the causative agent of the severe bovine anaplasmosis. The tick Rhipicephalus microplus is one of the main vectors of A. marginale in tropical and subtropical regions of the world. After the tick bite, the bacterium invades and proliferates within the bovine erythrocytes leading to anemia, impairment of milk production and weight loss. In addition, infection can cause abortion and high mortality in areas of enzootic instability. Immunization with live and inactivated vaccines are employed to control acute bovine anaplasmosis. However, they do not prevent persistent infection. Consequently, infected animals, even if immunized, are still reservoirs of the bacterium and contribute to its dissemination. Antimicrobials are largely employed for the prophylaxis of bovine anaplasmosis. However, they are often used in sublethal doses which may select pre-existing resistant bacteria and induce genetic or phenotypic variations. Therefore, we propose a new standardized in vitro assay to evaluate the susceptibility of A. marginale strains to different antimicrobials. This tool will help health professionals to choose the more adequate treatment for each herd which will prevent the selection and spread of resistant strains. For that, we initially evaluated the antimicrobial susceptibility of two field isolates of A. marginale (Jaboticabal and Palmeira) infecting bovines. The least susceptible strain (Jaboticabal) was used for the standardization of an antimicrobial assay using a culture of Ixodes scapularis-derived tick cell line, ISE6. Results showed that enrofloxacin (ENRO) at 0.25, 1 or 4 µg/mL and oxytetracycline (OTC) at 4 or 16 µg/mL are the most efficient treatments, followed by OTC at 1 µg/mL and imidocarb dipropionate (IMD) at 1 or 4 µg/mL. In addition, this proposed tool has technical advantages compared to the previously established bovine erythrocyte culture. Thereby, it may be used to guide cattle farmers to the correct use of antimicrobials. The choice of the most suitable antimicrobial is essential to eliminate persistent infections, prevent the spread of resistant strains and help controlling of bovine anaplasmosis.

Factores de riesgo asociados a mortalidad en recién nacidos con hernia diafragmática congénita / Risk factors associated with mortality in newborn infants with congenital diaphragmatic hernia

Introducción. La hernia diafragmática congénita presenta alta morbimortalidad. Existen herramientas para predecir sobrevida, tanto prenatal (índice pulmón-cabeza observado/esperado ­observed/expected lung-to-head ratio; OE-LHR, por sus siglas en inglés­, presencia de hígado en tórax) como posnatal (puntaje del Grupo de Estudio sobre Hernia Diafragmática Congénita, Congenital Diaphragmatic Hernia Study Group, CDHSG). El objetivo fue identificar factores de riesgo asociados a mortalidad y estimar la mortalidad ajustada por riesgo prenatal en el subgrupo de pacientes con hernia izquierda aislada.Población y métodos. Estudio retrospectivo y analítico de pacientes nacidos en el Hospital Italiano de Buenos Aires durante 2011-2018. Se realizó un análisis multivariable para evaluar factores de riesgo asociados a mortalidad. Para la mortalidad ajustada por riesgo prenatal, se realizó una razón entre la mortalidad observada y la media "esperada" según el OE-LHR.Resultados. Se incluyeron 53 pacientes. La mediana de edad gestacional fue 38 semanas, y la media de peso al nacer, 3054 gramos. El 73 % de los pacientes tuvo hernia aislada. La mortalidad global fue del 45 %, mayor en pacientes con malformaciones asociadas. En el análisis multivariable, la presencia de hipertensión pulmonar grave estimada por ecocardiografía postnatal se asoció en forma independiente a mortalidad: (odds ratio ajustado 6,4; IC 95 %: 1,02-40). La mortalidad global observada en pacientes con hernia izquierda aislada fue similar a la esperada (razón 1,05).Conclusión. La mortalidad global es similar a la esperada según el OE-LHR. En nuestra población, la hipertensión pulmonar grave luego del nacimiento resultó determinante de la mortalidad.

Introduction. Morbidity and mortality are high in congenital diaphragmatic hernia. Some tools help to predict survival, both prenatally (observed/expected lung-to-head ratio [OE-LHR], presence of the liver in the chest) and postnatally (Congenital Diaphragmatic Hernia Study Group [CDHSG] score). Our objective was to identify the risk factors associated with mortality and estimate the risk-adjusted mortality in the prenatal period in the subgroup of patients with isolated left-sided hernia.Population and methods. Retrospective and analytical study of patients born at Hospital Italiano de Buenos Aires between 2011 and 2018. A multivariate analysis was done to assess mortality-associated risk factors. For risk-adjusted mortality in the prenatal period, the ratio between the observed mortality and the mean "expected" mortality based on the OE-LHR was estimated.Results. A total of 53 patients were included. Their median gestational age was 38 weeks, and their mean birth weight was 3054 g. Isolated hernia was observed in 73 % of patients. Overall mortality was 45 %, and higher in patients with associated malformations. In the multivariate analysis, the presence of severe pulmonary hypertension estimated by postnatal echocardiogram was independently associated with mortality (adjusted odds ratio: 6.4, 95 % confidence interval: 1.02-40). The observed overall mortality in patients with isolated left-sided hernia was similar to that expected (ratio: 1.05).Conclusion. Overall mortality was similar to that expected based on the OE-LHR. In our population, severe pulmonary hypertension after birth was a determining factor of mortality

Risk factors associated with mortality in newborn infants with congenital diaphragmatic hernia. / Factores de riesgo asociados a mortalidad en recién nacidos con hernia diafragmática congénita.

INTRODUCTION: Morbidity and mortality are high in congenital diaphragmatic hernia. Some tools help to predict survival, both prenatally (observed/expected lung-to-head ratio [OELHR], presence of the liver in the chest) and postnatally (Congenital Diaphragmatic Hernia Study Group [CDHSG] score). Our objective was to identify the risk factors associated with mortality and estimate the risk-adjusted mortality in the prenatal period in the subgroup of patients with isolated left-sided hernia. POULATION AND METHODS: Retrospective and analytical study of patients born at Hospital Italiano de Buenos Aires between 2011 and 2018. A multivariate analysis was done to assess mortality-associated risk factors. For riskadjusted mortality in the prenatal period, the ratio between the observed mortality and the mean "expected" mortality based on the OELHR was estimated. RESULTS: A total of 53 patients were included. Their median gestational age was 38 weeks, and their mean birth weight was 3054 g. Isolated hernia was observed in 73 % of patients. Overall mortality was 45 %, and higher in patients with associated malformations. In the multivariate analysis, the presence of severe pulmonary hypertension estimated by postnatal echocardiogram was independently associated with mortality (adjusted odds ratio: 6.4, 95 % confidence interval: 1.02-40). The observed overall mortality in patients with isolated left-sided hernia was similar to that expected (ratio: 1.05). CONCLUSION: Overall mortality was similar to that expected based on the OE-LHR. In our population, severe pulmonary hypertension after birth was a determining factor of mortality.

Introducción. La hernia diafragmática congénita presenta alta morbimortalidad. Existen herramientas para predecir sobrevida, tanto prenatal (índice pulmón-cabeza observado/ esperado ­observed/expected lung-to-head ratio; OE-LHR, por sus siglas en inglés­, presencia de hígado en tórax) como posnatal (puntaje del Grupo de Estudio sobre Hernia Diafragmática Congénita, Congenital Diaphragmatic Hernia Study Group, CDHSG). El objetivo fue identificar factores de riesgo asociados a mortalidad y estimar la mortalidad ajustada por riesgo prenatal en el subgrupo de pacientes con hernia izquierda aislada. Población y métodos. Estudio retrospectivo y analítico de pacientes nacidos en el Hospital Italiano de Buenos Aires durante 2011-2018. Se realizó un análisis multivariable para evaluar factores de riesgo asociados a mortalidad. Para la mortalidad ajustada por riesgo prenatal, se realizó una razón entre la mortalidad observada y la media "esperada" según el OE-LHR. Resultados. Se incluyeron 53 pacientes. La mediana de edad gestacional fue 38 semanas, y la media de peso al nacer, 3054 gramos. El 73 % de los pacientes tuvo hernia aislada. La mortalidad global fue del 45 %, mayor en pacientes con malformaciones asociadas. En el análisis multivariable, la presencia de hipertensión pulmonar grave estimada por ecocardiografía postnatal se asoció en forma independiente a mortalidad: (odds ratio ajustado 6,4; IC 95 %: 1,02- 40). La mortalidad global observada en pacientes con hernia izquierda aislada fue similar a la esperada (razón 1,05). Conclusión. La mortalidad global es similar a la esperada según el OE-LHR. En nuestra población, la hipertensión pulmonar grave luego del nacimiento resultó determinante de la mortalidad.

Randomized Controlled Trial of Nonsynchronized Nasal Intermittent Positive Pressure Ventilation versus Nasal CPAP after Extubation of VLBW Infants.

BACKGROUND AND OBJECTIVES: Nasal continuous positive airway pressure (NCPAP) is a useful method of respiratory support after extubation. However, some infants fail despite CPAP use and require reintubation. Some evidence suggests that synchronized nasal intermittent positive pressure ventilation (NIPPV) may decrease extubation failure in preterm infants. Nonsynchronized NIPPV (NS-NIPPV) is being widely used in preterm infants without conclusive evidence of its benefits and side effects. Our aim was to evaluate whether NS-NIPPV decreases extubation failure compared with NCPAP in ventilated very low birth weight infants (VLBWI) with respiratory distress syndrome (RDS). METHODS: Randomized controlled trial of ventilated VLBWI being extubated for the first time. Before extubation, infants were randomized to receive NCPAP or NS-NIPPV. Primary outcome was the need for reintubation within 72 h. RESULTS: 220 infants were included. The mean ± SD birth weight was 1,027 ± 256 g and gestational age 27.8 ± 1.9 weeks. Demographic and clinical characteristics were similar in both groups. Extubation failure was 32.4% for NCPAP versus 32.1% for NS-NIPPV, p = 0.98. The frequency of deaths, bronchopulmonary dysplasia, intraventricular hemorrhage, air leaks, necrotizing enterocolitis and duration of respiratory support did not differ between groups. CONCLUSIONS: In this population of VLBWI, NS-NIPPV did not decrease extubation failure after RDS compared with NCPAP.

Impacto del volumen de sangre extraído por flebotomía sobre el requerimiento transfusional en prematuros menores de 1500 g. Estudio cuasiexperimental / Impact of the volume of blood collected by phlebotomy on transfusion requirements in preterm infants with birth weight of less than 1500 g. A quasi-experimental study

Introducción. La anemia es una complicación para los recién nacidos de muy bajo peso al nacer, y los exámenes de laboratorio son un factor de riesgo preponderante. Más del 50 % recibe, al menos, una transfusión de glóbulos rojos. Estas se han asociado a mayor riesgo de infecciones, hemorragia intracraneal, enterocolitis necrotizante y displasia broncopulmonar. En 2012, se implementó, en el Hospital Italiano de Buenos Aires, una estrategia de menor volumen de extracción de sangre por flebotomía. El objetivo del presente estudio fue evaluar su asociación con el número detransfusiones.Métodos. Estudio cuasiexperimental del tipo antes/después. Se comparó el número de transfusiones entre dos grupos de prematuros de muy bajo peso con diferente volumen de extracción. Se evaluó la correlación entre el volumen extraído y el número de transfusiones estimando el coeficiente de Spearman. Para ajustar por confundidores, se realizó un modelo de regresión logística.Resultados. Se incluyeron en el estudio 178 pacientes con edad gestacional media de 29,4 semanas (desvío estándar: 2,7) y peso al nacer de 1145 gramos (875-1345). El perfil de la serie roja inicial fue similar entre ambos grupos. El número de transfusiones (p = 0,017) y el volumen transfundido (p = 0,048) disminuyeron significativamente. El coeficiente de correlación resultó de 0,83. En el análisis multivariado, volumen de extracción y peso al nacer se asociaron a un requerimiento mayor de 3 transfusiones.Conclusión. Un menor volumen de extracción de sangre en prematuros de muy bajo peso está asociado de manera independiente a menor requerimiento transfusional.

Introduction. Anemia is a complication in very low birth weight (VLBW) infants, and lab tests are a predominant risk factor. At least one red blood cell transfusion is given in more than 50 % of cases. Transfusions are associated with a higher risk for infections, intracranial hemorrhage, necrotizing enterocolitis, and bronchopulmonary dysplasia. In 2012, Hospital Italiano de Buenos Aires implemented a strategy to collect a lower blood volume by phlebotomy. The objective of this study was to assess its association with the number of transfusions.Methods. Before-and-after, quasi-experimental study. The number of transfusions was compared between two groups of VLBW preterm infants with different blood collection volumes. The correlation between the collection volume and the number of transfusions was assessed estimating Spearman's coefficient. A logistic regression model was used to adjust for confounders.Results. The study included 178 patients with a mean gestational age of 29.4 weeks (standard deviation: 2.7) and a birth weight of 1145 g (875-1345). The baseline red series profile was similar between both groups. The number of transfusions (p = 0.017) and the transfusion volume (p = 0.048) decreased significantly. The correlation coefficient was 0.83. In the multivariate analysis, collection volume and birth weight were associated with a requirement of more than three transfusions.Conclusion. A lower blood collection volume in VLBW preterm infants is independently associated with fewer transfusion requirements.

Impact of the volume of blood collected by phlebotomy on transfusion requirements in preterm infants with birth weight of less than 1500 g. A quasi-experimental study. / Impacto del volumen de sangre extraído por flebotomía sobre el requerimiento transfusional en prematuros menores de 1500 g. Estudio cuasiexperimental.

INTRODUCTION: Anemia is a complication in very low birth weight (VLBW) infants, and lab tests are a predominant risk factor. At least one red blood cell transfusion is given in more than 50 % of cases. Transfusions are associated with a higher risk for infections, intracranial hemorrhage, necrotizing enterocolitis, and bronchopulmonary dysplasia. In 2012, Hospital Italiano de Buenos Aires implemented a strategy to collect a lower blood volume by phlebotomy. The objective of this study was to assess its association with the number of transfusions. METHODS: Before-and-after, quasi-experimental study. The number of transfusions was compared between two groups of VLBW preterm infants with different blood collection volumes. The correlation between the collection volume and the number of transfusions was assessed estimating Spearman's coefficient. A logistic regression model was used to adjust for confounders. RESULTS: The study included 178 patients with a mean gestational age of 29.4 weeks (standard deviation: 2.7) and a birth weight of 1145 g (875-1345). The baseline red series profile was similar between both groups. The number of transfusions (p = 0.017) and the transfusion volume (p = 0.048) decreased significantly. The correlation coefficient was 0.83. In the multivariate analysis, collection volume and birth weight were associated with a requirement of more than three transfusions. CONCLUSION: A lower blood collection volume in VLBW preterm infants is independently associated with fewer transfusion requirements.

Introducción. La anemia es una complicación para los recién nacidos de muy bajo peso al nacer, y los exámenes de laboratorio son un factor de riesgo preponderante. Más del 50 % recibe, al menos, una transfusión de glóbulos rojos. Estas se han asociado a mayor riesgo de infecciones, hemorragia intracraneal, enterocolitis necrotizante y displasia broncopulmonar. En 2012, se implementó, en el Hospital Italiano de Buenos Aires, una estrategia de menor volumen de extracción de sangre por flebotomía. El objetivo del presente estudio fue evaluar su asociación con el número de transfusiones. Métodos. Estudio cuasiexperimental del tipo antes/después. Se comparó el número de transfusiones entre dos grupos de prematuros de muy bajo peso con diferente volumen de extracción. Se evaluó la correlación entre el volumen extraído y el número de transfusiones estimando el coeficiente de Spearman. Para ajustar por confundidores, se realizó un modelo de regresión logística. Resultados. Se incluyeron en el estudio 178 pacientes con edad gestacional media de 29,4 semanas (desvío estándar: 2,7) y peso al nacer de 1145 gramos (875-1345). El perfil de la serie roja inicial fue similar entre ambos grupos. El número de transfusiones (p = 0,017) y el volumen transfundido (p = 0,048) disminuyeron significativamente. El coeficiente de correlación resultó de 0,83. En el análisis multivariado, volumen de extracción y peso al nacer se asociaron a un requerimiento mayor de 3 transfusiones. Conclusión. Un menor volumen de extracción de sangre en prematuros de muy bajo peso está asociado de manera independiente a menor requerimiento transfusional.

Heated Humidifier versus Heat-and-Moisture Exchanger During Positive Pressure Ventilation With a T-Piece Resuscitator in Rabbits.

BACKGROUND: There are many proven benefits of the use of conditioned gases in mechanically ventilated patients. In spite of this, its use in the delivery room is limited, perhaps because of known difficulties with heated humidifiers (HH); moreover, there is no evidence regarding the use of heat-and-moisture exchangers (HME) in a delivery room setting. We sought to asess the airway's absolute humidity level using three diferents strategies: HH, HME and unconditioned gases. METHODS: We conducted an experimental study in 12 intubated rabbits ventilated with a T-piece resuscitator. Absolute humidity levels in inspired gases were measured at baseline and at 5, 10, 15, and 20 min while using HH, HME, or no conditioning method (ie, unconditioned). The animals were initially randomized to one of the 3 interventions, and each animal underwent the other methods with at least 24 h between each test. RESULTS: There were no differences in vital signs at baseline or at the end of the procedures. Mean absolute humidity at the end of the tests was 38.2 ± 1.7 g/m3 for HH, 28.9 ± 4.7 g/m3 for HME, and 13.9 ± 5.1 g/m3 for unconditioned gas (P = .003). CONCLUSIONS: During ventilation with a T-piece resuscitator, the absolute humidity was the highest with HH. The absolute humidity with HME was lower, but it was still significantly more than that with unconditioned gas. Therefore, the use of a T-piece resuscitator with HME could be a good alternative to HH given that positive-pressure ventilation is used ideally for short periods of time in the delivery room.

Comparative analysis of the midgut microbiota of two natural tick vectors of Rickettsia rickettsii.

Although the ticks Amblyomma sculptum and Amblyomma aureolatum are important vectors of Rickettsia rickettsii, causative agent of the life-threatening Rocky Mountain spotted fever, A. aureolatum is considerably more susceptible to infection than A. sculptum. As the microbiota can interfere with the colonization of arthropod midgut (MG) by pathogens, in the current study we analyzed the MG microbiota of both tick species. Our results revealed that the MG of A. aureolatum harbors a prominent microbiota, while A. sculptum does not. Remarkably, a significant reduction of the bacterial load was recorded in R. rickettsii-infected A. aureolatum. In addition, the taxonomy analysis of the MG bacterial community of A. aureolatum revealed a dominance of the genus Francisella, suggesting an endosymbiosis. This study is the first step in getting insights into the mechanisms underlying the interactions among Amblyomma species, their microbiota and R. rickettsii. Additional studies to better understand these mechanisms are required and may help the development of novel alternatives to block rickettsial transmission.

Reporte voluntario y anónimo de errores de medicación en pacientes hospitalizados en un Departamento de Pediatría / Voluntary and anonymous reporting of medication errors in patients admitted to the Department of Pediatrics

Objetivo. Evaluar reportes de errores de medicación en niños hospitalizados para determinar las frecuencias, causas y eventos adversos (EA). Métodos. Estudio prospectivo de reportes de errores de medicación de Terapia Neonatal (UCIN), Clínica Pediátrica (CP) y Terapia Pediátrica (UCIP). Se excluyeron reportes de pediatría ambulatoria y datos incompletos. Se evaluaron las variables relacionadas. Resultados. De 989 errores reportados en pediatría, los de medicación fueron 401 (41 %). De ellos, 353 (88 %) llegaron a los pacientes y 48 (12 %) fueron cuasierrores. El 42 % ocurrieron a la mañana; 24 %, tarde; 17 %, mañana y tarde, y 17 %, noche; diferencias no significativas (p = 0,18). El error más frecuente fue dosis equivocada, 118 (33,4 %). Los reportes de errores de prescripción fueron 160 (45 %); administración, 149 (42 %), y dispensación, 44 (2,5 %). Los errores de dosis fueron más frecuentes en la prescripción (p < 0,05). La UCIN reportó la mayor cantidad de errores, 179 (50 %); CP, 91 (25,5 %), y UCIP, 83 (24,5 %). Hubo un total de 91 EA reportados (22,5 %); la mayoría leves, 53 (58 %), y moderados, 31 (34 %). La UCIN reportó 53 EA (58 %); UCIP, 25 (27 %), y CP, 18 (19,7 %). No ocurrieron fallecimientos.Conclusión. La tasa de errores de medicación reportados en niños hospitalizados fue de 41 %. Los errores en las dosis de medicamentos fueron los más frecuentes. Hubo 91 EA; prevalecieron los leves (58 %); la UCIN reportó el mayor número (58 %).

Objective. To assess reports of medication errors in hospitalized children to establish their frequency, causes, and adverse events (AEs). Methods. Prospective study of medication errors reported at the Neonatal Intensive Care Unit (NICU), Pediatric Clinic (PC), and Pediatric intensive Care Unit (PICU). Ambulatory Pediatrics reports and incomplete data were excluded. Related variables were evaluated. Results. Out of 989 errors reported in Department of Pediatrics, 401 (41 %) corresponded to medication errors. Of these, 353 (88 %) reached patients and 48 (12 %) were quasi-errors; 42 % occurred in the morning; 24 %, in the afternoon; 17 %, in the morning and afternoon, and 17 %, in the night; differences were not significant (p = 0.18). Dosing errors were the most common ones, 118 (33.4 %). In total, 160 reports (45 %) corresponded to prescription errors; 149 (42 %), to administration errors; and 44 (2.5 %), to dispensing errors. Dosing errors were more common in prescriptions (p < 0.05). The highest number of errors was reported at the NICU, 179 (50 %); compared to 91 (25.5 %) at the PC and 83 (24.5 %) at the PICU. A total of 91 AEs were reported (22.5 %); most were mild, 53 (58 %), or moderate, 31 (34 %). The NICU reported 53 AEs (58 %); the PICU, 25 (27 %); and the DCP, 18 (19.7 %). No deaths occurred.Conclusion. The rate of medication errors reported in hospitalized children was 41 %. Dosing errors were the most common ones. A total of 91 AEs were reported; most were mild (58 %); the highest number was reported at the NICU (58 %).

Voluntary and anonymous reporting of medication errors in patients admitted to the Department of Pediatrics. / Reporte voluntario y anónimo de errores de medicación en pacientes hospitalizados en un Departamento de Pediatría.

OBJECTIVE: To assess reports of medication errors in hospitalized children to establish their frequency, causes, and adverse events(AEs). METHODS: Prospective study of medication errors reported at the Neonatal Intensive Care Unit (NICU), Pediatric Clinic (PC), and Pediatric intensive Care Unit (PICU). Ambulatory Pediatrics reports and incomplete data were excluded. Related variables were evaluated. RESULTS: Out of 989 errors reported in Department of Pediatrics, 401 (41 %) corresponded to medication errors. Of these, 353 (88 %) reached patients and 48 (12 %) were quasi-errors; 42 % occurred in the morning; 24 %, in the afternoon; 17 %, in the morning and afternoon, and 17 %, in the night; differences were not significant (p = 0.18). Dosing errors were the most common ones, 118 (33.4 %). In total, 160 reports (45 %) corresponded to prescription errors; 149 (42 %), to administration errors; and 44 (2.5 %), to dispensing errors. Dosing errors were more common in prescriptions (p < 0.05). The highest number of errors was reported at the NICU, 179 (50 %); compared to 91 (25.5 %) at the PC and 83 (24.5 %) at the PICU. A total of 91 AEs were reported (22.5 %); most were mild, 53 (58 %), or moderate, 31 (34 %). The NICU reported 53 AEs (58 %); the PICU, 25 (27 %); and the DCP, 18 (19.7 %). No deaths occurred. CONCLUSION: The rate of medication errors reported in hospitalized children was 41 %. Dosing errors were the most common ones. A total of 91 AEs were reported; most were mild (58 %); the highest number was reported at the NICU (58 %).

Objetivo. Evaluar reportes de errores de medicación en niños hospitalizados para determinar las frecuencias, causas y eventos adversos (EA). Métodos. Estudio prospectivo de reportes de errores de medicación de Terapia Neonatal (UCIN), Clínica Pediátrica (CP) y Terapia Pediátrica (UCIP). Se excluyeron reportes de pediatría ambulatoria y datos incompletos. Se evaluaron las variables relacionadas. Resultados. De 989 errores reportados en pediatría, los de medicación fueron 401 (41 %). De ellos, 353 (88 %) llegaron a los pacientes y 48 (12 %) fueron cuasierrores. El 42 % ocurrieron a la mañana; 24 %, tarde; 17 %, mañana y tarde, y 17 %, noche; diferencias no significativas (p = 0,18). El error más frecuente fue dosis equivocada, 118 (33,4 %). Los reportes de errores de prescripción fueron 160 (45 %); administración, 149 (42 %), y dispensación, 44 (2,5 %). Los errores de dosis fueron más frecuentes en la prescripción (p < 0,05). La UCIN reportó la mayor cantidad de errores, 179 (50 %); CP, 91 (25,5 %), y UCIP, 83 (24,5 %). Hubo un total de 91 EA reportados (22,5 %); la mayoría leves, 53 (58 %), y moderados, 31 (34 %). La UCIN reportó 53 EA (58 %); UCIP, 25 (27 %), y CP, 18 (19,7 %). No ocurrieron fallecimientos. Conclusión. La tasa de errores de medicación reportados en niños hospitalizados fue de 41 %. Los errores en las dosis de medicamentos fueron los más frecuentes. Hubo 91 EA; prevalecieron los leves (58 %); la UCIN reportó el mayor número (58 %).

The Transcriptome of the Salivary Glands of Amblyomma aureolatum Reveals the Antimicrobial Peptide Microplusin as an Important Factor for the Tick Protection Against Rickettsia rickettsii Infection.

The salivary glands (SG) of ixodid ticks play a pivotal role in blood feeding, producing both the cement and the saliva. The cement is an adhesive substance that helps the attachment of the tick to the host skin, while the saliva contains a rich mixture of antihemostatic, anti-inflammatory, and immunomodulatory substances that allow ticks to properly acquire the blood meal. The tick saliva is also a vehicle used by several pathogens to be transmitted to the vertebrate host, including various bacterial species from the genus Rickettsia. Rickettsia rickettsii is a tick-borne obligate intracellular bacterium that causes the severe Rocky Mountain spotted fever. In Brazil, the dog yellow tick Amblyomma aureolatum is a vector of R. rickettsii. In the current study, the effects of an experimental infection with R. rickettsii on the global gene expression profile of A. aureolatum SG was determined by next-generation RNA sequencing. A total of 260 coding sequences (CDSs) were modulated by infection, among which 161 were upregulated and 99 were downregulated. Regarding CDSs in the immunity category, we highlight one sequence encoding one microplusin-like antimicrobial peptide (AMP) (Ambaur-69859). AMPs are important effectors of the arthropod immune system, which lack the adaptive response of the immune system of vertebrates. The expression of microplusin was confirmed to be significantly upregulated in the SG as well as in the midgut (MG) of infected A. aureolatum by a quantitative polymerase chain reaction preceded by reverse transcription. The knockdown of the microplusin expression by RNA interference caused a significant increase in the prevalence of infected ticks in relation to the control. In addition, a higher rickettsial load of one order of magnitude was recorded in both the MG and SG of ticks that received microplusin-specific dsRNA. No effect of microplusin knockdown was observed on the R. rickettsii transmission to rabbits. Moreover, no significant differences in tick engorgement and oviposition were recorded in ticks that received dsMicroplusin, demonstrating that microplusin knockdown has no effect on tick fitness. Further studies must be performed to determine the mechanism of action of this AMP against R. rickettsii.

Hipercalcemia e hipofosfatemia en prematuros que reciben nutrición parenteral agresiva / Hypercalcemia and hypophosphatemia among preterm infants receiving aggressive parenteral nutrition

Introducción. La nutrición parenteral agresiva constituye un estándar de cuidado en prematuros de muy bajo peso. Sin embargo, investigaciones recientes evaluaron su impacto en los resultados a corto plazo, como la homeostasis mineral y electrolítica. El objetivo fue comparar la prevalencia de hipercalcemia e hipofosfatemia en prematuros que recibían nutrición parenteral agresiva o estándar. Métodos. Estudio observacional retrospectivo que comparó a un grupo de prematuros menores de 1250 gramos que recibían nutrición parenteral agresiva con un grupo control histórico. Se calculó la prevalencia de hipercalcemia y se buscó la asociación con nutrición parenteral agresiva ajustando por confundidores. Se estimó la media de fosfatemia del grupo control mediante regresión lineal y se la comparó con el otro grupo. Resultados. Se incluyeron 40 pacientes por grupo. La prevalencia de hipercalcemia fue mayor en el grupo de nutrición parenteral agresiva (87,5% vs. 35%, p= 0,001). La nutrición parenteral agresiva se asoció con hipercalcemia al ajustar por peso al nacer, restricción del crecimiento intrauterino, aporte de aminoácidos y calorías (ORa 21,8; IC 95%: 3,7-128). La media de calcemia fue diferente entre ambos grupos (p= 0,002). El grupo de nutrición parenteral agresiva presentó más sepsis sin alcanzar significancia estadística y su fosfatemia media resultó menor que la estimada para el grupo control (p= 0,04). La prevalencia de hipofosfatemia en este grupo fue de 90% (IC 95%: 76-97%). Conclusiones. Nuestros datos muestran una asociación entre hipercalcemia/hipofosfatemia y nutrición parenteral agresiva. Se recomienda monitorizar la calcemia y la fosfatemia frecuentemente, ya que pueden estar asociadas con resultados clínicos adversos.

Introduction. Aggressive parenteral nutrition is the standard of care among very-low-birth weight preterm infants. However, in recent studies, its impact on short-term outcomes, has been evaluated. The objective was to compare the prevalence of hypercalcemia and hypophosphatemia among preterm infants receiving aggressive or standard parenteral nutrition. Methods. Observational, retrospective study comparing a group of preterm infants weighing less than 1250 grams who received aggressive parenteral nutrition with a historical control group. The prevalence of hypercalcemia was estimated and its association with aggressive parenteral nutrition was searched adjusting by confounders. The mean phosphate level was estimated for the control group by linear regression and was compared to the value in the other group. Results. Forty patients per group were included. The prevalence of hypercalcemia was higher in the group who received aggressive parenteral nutrition (87.5% versus 35%, p= 0.001). Aggressive parenteral nutrition was associated with hypercalcemia when adjusting by birth weight, intrauterine growth restriction, amino acid, and calorie intake (adjusted odds ratio: 21.8, 95% confidence interval -amp;#91;CI-amp;#93;: 3.7-128). The mean calcium level was different between both groups (p= 0.002). Infants who received aggressive parenteral nutrition had more sepsis without reaching statistical significance and the mean phosphate level was lower than that estimated for the control group (p= 0.04). The prevalence of hypophosphatemia in this group was 90% (95% CI: 76-97%). Conclusions. Our data show an association between hypercalcemia/hypophosphatemia and aggressive parenteral nutrition. It is recommended to frequently monitor calcium and phosphate levels since they might be associated with adverse clinical outcomes.

Hypercalcemia and hypophosphatemia among preterm infants receiving aggressive parenteral nutrition. / Hipercalcemia e hipofosfatemia en prematuros que reciben nutrición parenteral agresiva.

INTRODUCTION: Aggressive parenteral nutrition is the standard of care among very-low-birth weight preterm infants. However, in recent studies, its impact on short-term outcomes, has been evaluated. The objective was to compare the prevalence of hypercalcemia and hypophosphatemia among preterm infants receiving aggressive or standard parenteral nutrition. METHODS: Observational, retrospective study comparing a group of preterm infants weighing less than 1250 grams who received aggressive parenteral nutrition with a historical control group. The prevalence of hypercalcemia was estimated and its association with aggressive parenteral nutrition was searched adjusting by confounders. The mean phosphate level was estimated for the control group by linear regression and was compared to the value in the other group. RESULTS: Forty patients per group were included. The prevalence of hypercalcemia was higher in the group who received aggressive parenteral nutrition (87.5% versus 35%, p= 0.001). Aggressive parenteral nutrition was associated with hypercalcemia when adjusting by birth weight, intrauterine growth restriction, amino acid, and calorie intake (adjusted odds ratio: 21.8, 95% confidence interval [CI]: 3.7-128). The mean calcium level was different between both groups (p= 0.002). Infants who received aggressive parenteral nutrition had more sepsis without reaching statistical significance and the mean phosphate level was lower than that estimated for the control group (p= 0.04). The prevalence of hypophosphatemia in this group was 90% (95% CI: 76-97%). CONCLUSIONS: Our data show an association between hypercalcemia/hypophosphatemia and aggressive parenteral nutrition. It is recommended to frequently monitor calcium and phosphate levels since they might be associated with adverse clinical outcomes.

Introducción. La nutrición parenteral agresiva constituye un estándar de cuidado en prematuros de muy bajo peso. Sin embargo, investigaciones recientes evaluaron su impacto en los resultados a corto plazo, como la homeostasis mineral y electrolítica. El objetivo fue comparar la prevalencia de hipercalcemia e hipofosfatemia en prematuros que recibían nutrición parenteral agresiva o estándar. Métodos. Estudio observacional retrospectivo que comparó a un grupo de prematuros menores de 1250 gramos que recibían nutrición parenteral agresiva con un grupo control histórico. Se calculó la prevalencia de hipercalcemia y se buscó la asociación con nutrición parenteral agresiva ajustando por confundidores. Se estimó la media de fosfatemia del grupo control mediante regresión lineal y se la comparó con el otro grupo. Resultados. Se incluyeron 40 pacientes por grupo. La prevalencia de hipercalcemia fue mayor en el grupo de nutrición parenteral agresiva (87,5% vs. 35%, p= 0,001). La nutrición parenteral agresiva se asoció con hipercalcemia al ajustar por peso al nacer, restricción del crecimiento intrauterino, aporte de aminoácidos y calorías (ORa 21,8; IC 95%: 3,7-128). La media de calcemia fue diferente entre ambos grupos (p= 0,002). El grupo de nutrición parenteral agresiva presentó más sepsis sin alcanzar significancia estadística y su fosfatemia media resultó menor que la estimada para el grupo control (p= 0,04). La prevalencia de hipofosfatemia en este grupo fue de 90% (IC 95%: 76-97%). Conclusiones. Nuestros datos muestran una asociación entre hipercalcemia/hipofosfatemia y nutrición parenteral agresiva. Se recomienda monitorizar la calcemia y la fosfatemia frecuentemente, ya que pueden estar asociadas con resultados clínicos adversos.