Cristián Belmar

Gestational diabetes and pre‐pregnancy overweight: Possible factors involved in newborn macrosomia

Aim:  Good glycemic control in gestational diabetes mellitus (GDM) seems not to be enough to prevent macrosomia (large‐for‐gestational‐age newborns). In GDM pregnancies we studied the effects of glycemic control (as glycosylated hemoglobin [HbA1c]), pre‐pregnancy body mass index (PP‐BMI) and gestational weight gain per week (GWG‐W) on the frequency of macrosomia.

Maternal hypertriglyceridemia: A link between maternal overweight-obesity and macrosomia in gestational diabetes

Infants born from overweight and obese mothers with glucose‐controlled gestational diabetes (GDM) tend to be large‐for‐gestational age (LGA). It is hypothesized that this is due to an excessive rise in maternal triglyceride levels.

Functional link between adenosine and insulin: a hypothesis for fetoplacental vascular endothelial dysfunction in gestational diabetes.

Gestational diabetes mellitus (GDM) is a syndrome compromising the health of the mother and the fetus. Endothelial damage and reduced metabolism of the vasodilator adenosine occur and fetal hyperinsulinemia associated with deficient insulin response and a metabolic rather than mitogenic phenotype is characteristic of this pathology. These phenomena lead to endothelial dysfunction of the fetoplacental unit. Major databases were searched for the relevant literature in the field. Special attention was placed on publications related with diabetes and hormone/metabolic disorders. We aimed to summarize the information regarding insulin sensitivity changes in GDM and the role of adenosine in this phenomenon. Evidence supporting the possibility that fetal endothelial dysfunction involves a functional link between adenosine and insulin signaling in the fetal endothelium from GDM pregnancies is summarized. Since insulin acts via membrane receptors type A (preferentially associated with mitogenic responses) or type B (preferentially associated with metabolic responses), a differential activation of these receptors in this syndrome is proposed.

La hipótesis de Pedersen no es suficiente: Otros nutrientes además de la glucosa explicarían la macrosomía fetal en pacientes diabéticas gestacionales con sobrepeso y buen control glicémico

Since 1964, the hypothesis of Pedersen has been used to explain fetal macrosomia observed in gestational diabetes mellitus (GDM), by a mechanism involving maternal hyperglycemia--fetal hyperglycemia--fetal hyperinsulinemia. However, since the 1980-89 decade, it is known that pregnant women with pre-gestational overweight not suffering from GDM still have a higher frequency of fetal macrosomia. Furthermore, pregnant women with GDM, despite being subjected to optimal glycemic control, still show unacceptably high frequencies of fetal macrosomia, a phenomenon that is concentrated in pregnancies with overweight or obesity prior to pregnancy. If glucose is not the single nutrient responsible for fetal macrosomia in pregnant women with gestational diabetes that undergo strict glycemic control, other nutrients may cause excessive fetal growth in pre-pregnancy overweight mothers. In this review, we propose that triglycerides (TG) could be responsible for this accelerated fetal growth. If this hypothesis is validated in animal models and clinical studies, then normal and pathological ranges of TG should be defined, and monitoring of triglyceride levels during pregnancy should be advised as a possible new alternative, besides a good glycemic control, for the management of fetal macrosomia in GDM women with overweight prior to pregnancy.

Determinación de la portación de streptococcus agalactiae: grupo B en embarazadas durante el tercer trimestre mediante inmunoensayo

RESUMENDado que la sepsis neonatal por Streptococcus Grupo B es una enfermedad de alta letalidad, yconsiderando ademas que la portacion de este germen en nuestra poblacion de embarazadas se acercaa 20%, es que, resulta muy importante disponer de algun test rapido y confiable para realizar screening.Este estudio evalua el rendimiento de un inmunoensayo para pesquisa de Streptococcus agalactiae enembarazadas sin factores de riesgo y a fines del tercer trimestre. Los resultados muestran una bajasensibilidad y un bajo valor predictivo positivo para este metodo, lo que no lo hace recomendable para suimplementacion clinica.PALABRAS CLAVES: Sepsis por Streptococcus Grupo B, inmunoensayoSUMMARYNeonatal sepsis of early onset by group B Streptococcus has a high mortality rate. Twenty percent ofour pregnant population have vaginal colonization by this bacterial agent, so clinical practice require a fastand efficient screening test.This report checks a Group B Streptococcus immunoassay screening test in the last trimester forpregnant women without risk factors. The low sensitivity and low positive predictive value of the test makeit not recomendable for clinical practice.KEY WORDS: Group B Streptococcus, immunoassay, perinatal sepsis

PREVALENCIA DE COLONIZACION POR STREPTOCOCCUS AGALACTIAE (GRUPO B) EN EL TERCER TRIMESTRE DEL EMBARAZO. EVALUACION DEL CULTIVO SELECTIVO. EXPERIENCIA EN 2192 PACIENTES

SUMMARY Group B Streptococcus (GBS) is the most important bacterial agent in early-onset neonatal sepsis. Infection is usually acquired during labor in colonized women. Among pregnant women streptococcal colonization ranges from 2% to 34%, with highgest rates when using combined vaginal and anal culture in a selective broth medium. The aim of this study was to know the GBS prevalence in pregnant women controlled in our hospital and the real improvement in GBS recovery because the use of selective media. Among 2192 pregnant women enrolled, using selective medium, we identifed GBS in 19.8% of them. With non selective medium the prevalence would have reached only 12.7%. This finding support the systematic screening for GBS in our hospital, using selective medium only.