Análise morfológica dos órgãos de stress de autopsias perinatais.

Abstract

Introduction: The aim of this study was evaluated through immunohistochemical and morphometrical techniques the morphology of the organs that had been previously described in the literature as stress organs, with morphological injuries due to perinatal stress: adrenal gland (AG), thymus (TY), liver (LI) and placenta (PL), in 3 different types of perinatal death: Perinatal Hypoxia/Anoxia (PHA), Ascending Infection (AI)) and Congenital Malformations (CM). Material and Methods: We analyzed 146 cases, 84 (51,2 %) PHA, 34 (20,7 %) AI and 30 (18,4 %) CM. The hematoxylin-eosin stain was used to the analysis of the adrenal gland vacuolization; hepatic steatosis and extramedullary erythropoiesis quantification in the LI. For the LI fibrosis the Picro Sirius staining was used. For the immunohistochemical analyses we used the antibodies CD68 (DAKO®), Anti-Tryptophan Hydroxylase antibody-Novus Biologicals®) and Anti- Melatonin Receptor 1A antibody Novus Biologicals®. Results: From the total evaluated autopsies the cases with PAH and AI had the bigger rate of stillborns babies (p <0,001). The autolysis was observed in 70 (42,7 %) cases, being more frequent in the cases with PAH (p <0,001). Of the 95 evaluated AG, the discreet standard of vacuolization was observed in 50 (52.6 %) of the cases, 21 (22.1 %) presented the moderate standard and 24 (25.3 %) the severe. The degree of vacuolization was higher in the cases with AI (p = 0.008). The material was of lipid nature as proved by the positive coloration for Sudam III. In the thymus the number of macrophages was significantly higher in the cases with PAH (p <0.001). There was no difference regarding the frequency of steatosis between the groups of cause of death. There was a positive and significant correlation between the degree of steatosis and the gestational age (Sr: 0.359, p = 0.002). In the liver the cases with PAH and AI presented the bigger percentage of hepatic fibrosis. The focuses of erythropoiesis varied in accordance with the gestational age, being more frequent in the premature independently of the cause of death (p = 0,012). The Anti-tryptophan-hydroxylase marker demonstrated cytoplasmic stain in the trophoblast and in the inflammatory cells of the intervillous space and for Anti- Melatonin Receptor 1A antibody the same structures were marked plus endothelial cell cytoplasm. The percentage of area of positive cells expression per field for the Anti-tryptophan-hydroxylase and Anti- Melatonin Receptor 1A was significantly higher in the cases with intrauterine stress (p=0,012). Conclusions: The analysis of the different anthropometrics parameters contributed to improve the interpretation of the perinatal autopsy findings. With the improvement of the perinatal care and the survival of the premature which had been exposed to intrauterine stimulus like PAH and AI, the description of the morphological injuries of the stress organs will help in future autopsy studies, and in the prevention of the diseases in the childhood such as hiper reactivity of the adrenal gland to hormones stimuli; thymus immunodepletion, hepatic fibrosis and injuries caused by the free radicals production.