Evaluación de la fracción de reticulocitos inmaduros como parámetro de ferropenia en el embarazo / Evaluation of the fraction of immature reticulocytes as a parameter of iron deficiency in pregnancy

Las embarazadas constituyen un grupo susceptible de desarrollar anemia ferropénica, la cual produce una alteración de la hematopoyesis, con aumento de reticulocitos principalmente a expensas de la fracción de reticulocitos inmaduros (IRF). El objetivo de este trabajo ha sido evaluar la sensibilidad (S) y especificidad (E) del IRF para el diagnóstico temprano de la deficiencia de hierro en el embarazo. Se obtuvieron muestras de sangre de 99 embarazadas que concurrieron al laboratorio del Hospital Vélez Sarsfield para su control prenatal. Se realizó el hemograma y el recuento reticulocitario en un autoanalizador hematológico, y se determinaron el hierro sérico y la ferritina. Se halló una sensibilidad de 76,1% y una especificidad de 53,1% por medio del análisis de la curva ROC (receiver- operating characteristic curve) para un valor de IRF de 0,35. La comparación de parámetros hematológicos y bioquímicos de las muestras con IRF menor o mayor a 0,35 muestran diferencias significativas (p<0,05). Por estos datos se podría recomendar esta prueba para el diagnóstico precoz de la deficiencia de hierro.

Pregnant women constitute a group capable of developing iron deficiency anemia, which causes a disturbance of hematopoiesis, with increased reticulocyte mainly at the expense of the immature reticulocyte fraction (IRF). The aim of this work was to assess IRF sensitivity (S) and specificity (E for its name in Spanish) for early diagnosis of iron deficiency in pregnancy. Blood samples from 99 pregnant women who attended Vélez Sarsfield Hospital Laboratory for prenatal care. Complete blood cells and reticulocyte automated counts were performed and serum iron and ferritin were analyzed. A 0.35 IRF cutoff was taken when the ROC curve (receiver-operating characteristic curve) was evaluated and a 76.1% sensitivity and 53.1%. specificity were found. Comparison of hematological and biochemical parameters of the samples with IRF lower and higher than 0.35 shows significant differences (p<0.05). These results make it possible to recommend this test for early diagnosis of iron deficiency.

Confirmation of neonatal screening: reference intervals and evaluation of methodological changes in TSH measurement.

Neonatal reference values for serum thyrotropin are scarce and comprise only small numbers of patients. During 2006, changes were made in IMMULITE kits for TSH measurement. To validate methodological changes, 80 serum samples from patients were evaluated and to establish reference intervals, 334 neonates and infants were analyzed (divided into 4 groups). Group 1 (G1) (48-72 h of life) (n=153), group 2A (G2A) (7-10 days of life) (n=65), group 2B (G2B) (11-14 days of life) (n=35), group 3 (G3) (28-40 days of life) (n=81). Current kits overestimate TSH results by 26 to 37%; TSH (mIU/L) reference intervals (percentile 2.5-97.5) were G1 (1.1-12.7), G2A (1.8-9.8), G2B (1.1-7.1) (p < 0.03 vs. G2A), G3 (1.2-6.9). We suggest that during the second week of life, reference values should be divided into an early stage and a late stage, at least, for there to be an adequate interpretation of borderline measurements in newborn thyroid screening.

Valores de referencia de la serie eritroide con tecnología del siglo XXI en embarazadas: Prevalencia de anemia / Reference values for the erythroid series with twenty-first century technology in pregnant women: Prevalence of anemia

La disponibilidad, en los hospitales, de contadores hematológicos con nueva tecnología hace necesario actualizar los valores de referencia para establecer el límite entre lo normal y lo patológico. Con este objetivo, se estableció cuáles son dichos valores en una población de mujeres embarazadas. Asimismo, se determinó el porcentaje de disminución de hemoglobina durante el embarazo por efecto de la dilución fisiológica, que fue del 2,2% del primero al segundo trimestre y del 1,5% del segundo al tercero, La prevalencia de anemia microcítica fue del 28% y de anemia macrocítica del 1,6%.

The availability in hospitals of blood cell counters using state-of-the-art technology has made it necessary to update the corresponding reference values. These values allow us to establish the boundary between normal and pathological. With this objective in mind, these intervals were established among pregnant women. Furthermore, the percentage of haemoglobin level decrease during pregnancy due to the effect of physiological dilution has been established as being of 2.2% between the first and the second trimester and 1.5% between the second and the third. The prevalence of microcytic anaemia was 28% and of macrocytic anaemia 1.6%.