[Frecuencia y gravedad de la retinopatía del prematuro en una unidad de cuidados intensivos neonatales].

INTRODUCTION: Retinopathy of prematurity (ROP) is a disease where retinal blood vessels do not develop normally and may cause visual damage and blindness. OBJECTIVE: To determine the frequency and severity of ROP in preterm newborns. METHOD: A descriptive, comparative study was carried out within the 2009-2013 period. Patients' general characteristics were recorded, including gestational age and postmenstrual age at the moment of ophthalmologic examination, as well as ROP severity and type of treatment. RESULTS: A total of 326 preterm newborns were included: 47.8 % (n = 156) had ROP; in 21.1 % it was severe (stage ≥ 3). Median gestational age was 28 weeks in preterm newborns with ROP, median birth weight was 1000 g, and median postmenstrual age at ophthalmological examination was 36 weeks. Of the infants with ROP, 71.1 % received treatment: 63.4 % of those who had mild ROP and 100 % of those with severe ROP. CONCLUSIONS: ROP frequency was high, higher than that reported in developed countries and similar to that in developing countries. The frequency of severe ROP was also higher. It is necessary for effective programs for the detection and opportune treatment of ROP to be established.

INTRODUCCIÓN: La retinopatía del prematuro (ROP) es una enfermedad en la que los vasos sanguíneos de la retina no se desarrollan normalmente, lo que puede ocasionar daño visual y ceguera. OBJETIVO: Identificar la frecuencia y gravedad de la ROP en recién nacidos prematuros. MÉTODO: Estudio descriptivo comparativo realizado en el periodo 2009-2013. Se registraron características generales de los pacientes, edad posnatal y edad posconcepcional al momento de la exploración oftalmológica, así como gravedad y tratamiento de la ROP. RESULTADOS: Se incluyeron 326 recién nacidos prematuros: 47.8 % (n = 156) tuvo ROP, en 21.1 % fue grave (estadio ≥ 3). La mediana de la edad gestacional fue de 28 semanas en los recién nacidos prematuros con ROP, el peso al nacer fue de 1000 g y la edad posconcepcional a la exploración oftalmológica fue de 36 semanas. De los niños con ROP, 71.1 % recibió tratamiento, 63.4 % de aquellos que tuvieron ROP leve y 100 % de aquellos con ROP grave. CONCLUSIONES: La frecuencia de ROP fue alta, mayor a la reportada en los países desarrollados y similar a la de otros países en desarrollo. La frecuencia de ROP grave también fue mayor. Es necesario establecer programas efectivos de detección y tratamiento oportuno de ROP.

miRNome landscape analysis reveals a 30 miRNA core in retinoblastoma.

BACKGROUND: miRNAs exert their effect through a negative regulatory mechanism silencing expression upon hybridizing to their target mRNA, and have a prominent position in the control of many cellular processes including carcinogenesis. Previous miRNA studies on retinoblastoma (Rb) have been limited to specific miRNAs reported in other tumors or to medium density arrays. Here we report expression analysis of the whole miRNome on 12 retinoblastoma tumor samples using a high throughput microarray platform including 2578 mature miRNAs. METHODS: Twelve retinoblastoma tumor samples were analyzed using an Affymetrix platform including 2578 mature miRNAs. We applied RMA analysis to normalize raw data, obtained categorical data from detection call values, and also used signal intensity derived expression data. We used Diana-Tools-microT-CDS to find miRNA targets and ChromDraw to map miRNAs in chromosomes. RESULTS: We discovered a core-cluster of 30 miRNAs that were highly expressed in all the cases and a cluster of 993 miRNAs that were uniformly absent in all cases. Another 1022 miRNA were variably present in the samples reflecting heterogeneity between tumors. We explored mRNA targets, pathways and biological processes affected by some of these miRNAs. We propose that the core-cluster of 30 miRs represent miRNA machinery common to all Rb, and affecting most pathways considered hallmarks of cancer. In this core, we identified miR-3613 as a potential and critical down regulatory hub, because it is highly expressed in all the samples and its potential mRNA targets include at least 36 tumor suppressor genes, including RB1. In the variably expressed miRNA, 36 were differentially expressed between males and females. Some of the potential pathways targeted by these 36 miRNAs were associated with hormonal production. CONCLUSION: These findings indicate that Rb tumor samples share a common miRNA expression profile regardless of tumor heterogeneity, and shed light on potential novel therapeutic targets such as mir-3613 This is the first work to delineate the miRNA landscape in retinoblastoma tumor samples using an unbiased approach.

Factores asociados con un mayor riesgo de retinopatía del prematuro en recién nacidos prematuros atendidos en un hospital de tercer nivel / Risk factors associated with retinopathy of prematurity in preterm infants treated at a tertiary level hospital

Introducción. La retinopatía del prematuro se define como una vitreorretinopatía proliferativa periférica en que la inmadurez -determinada por la edad gestacional y el peso al nacimiento- y el oxígeno son factores determinantes. El objetivo de este trabajo fue analizar el riesgo relativo para el desarrollo de la retinopatía del prematuro con respecto a la edad gestacional y el peso al nacimiento en prematuros. Métodos. Se realizó un estudio retrospectivo, análitico, transversal y unicéntrico en recién nacidos prematuros con una edad gestacional menor de 37 semanas y un peso al nacimiento menor de 2,000 g. Se realizó la exploración del fondo de ojo con oftalmoscopia binocular indirecta en diferentes tiempos de acuerdo con la edad gestacional. Las lesiones se registran siguiendo la clasificación internacional. Resultados. Se incluyeron dos grupos: uno de individuos sanos (grupo I) y otro de individuos con retinopatía del prematuro (grupo II). Se estudiaron 217 individuos sanos (91 femeninos y 126 masculinos) con una edad gestacional promedio de 30.95 ± 2.07 semanas y peso de 1,291.98 ± 255.93 g (620-2035 g). En el grupo II se estudiaron 127 pacientes (65 femeninos y 62 masculinos) con una edad gestacional promedio de 29.37 ± 1.77 semanas y peso de 1,089.31 ± 194.74 g (630-1650g). Predominó la retinopatía estadio 1 (70.1%), seguida de la retinopatía de estadio 2 (21.3%) y estadio 3 (7.1%). El 9.4% presentó retinopatía preumbral tipo 1 y el 4.7%, umbral. El grupo de 28-29 semanas presentó 2.37 veces más riesgo de desarrollar retinopatía del prematuro. Resultó el grupo con mayor incidencia (64.13%); a partir de las 30-31 semanas, el riesgo comenzó a disminuir. Conclusiones. Los recién nacidos prematuros con edad gestacional entre las 28 y 29 semanas tienen un riesgo mayor para desarrollar retinopatía del prematuro.

Background. Retinopathy of prematurity (ROP) is defined as a peripheral proliferative vitreoretinopathy in which immaturity (determined by gestational age and birth weight) and oxygen are more decisive factors. We undertook this study to analyze the relative risk for development of ROP in relation to gestational age and birth weight in infants. Methods. We carried out a retrospective, analytical, cross-sectional, single center trial in preterm infants with a gestational age <37 weeks and a birth weight <2,000 g. We performed fundus examination with binocular indirect ophthalmoscopy at different times according to gestational age. Injuries are accounted for using the international classification. Results. We included two groups: I) healthy individuals and II) those with retinopathy of prematurity. Group I included 217 healthy subjects, 91 females and 126 males, with a mean gestational age of 30.95 ± 2.7 weeks and a weight of 1291.98 ± 255.93 g (range: 620-2035). Group II was comprised of 127 patients, 65 females and 62 males with a mean gestational age of 29.37 ± 1.77 weeks (range: 26-34) and a weight of 1089.31 ± 194.74 g (range: 630-1650). Stage 1 retinopathy predominated (70.1%), followed by stage 2 (21.3%) and stage 3 (7.1%); 9.4% presented a type 1 prethreshold retinopathy and 4.7% threshold. The group of 28-29 weeks showed a factor of 2.37 times more risk of developing ROP and was the group with the highest incidence with 64.13% at 30-31 weeks after which the risk begins to decrease. Conclusions. Preterm infants with gestational age between 28 and 29 weeks are at increased risk for developing ROP.