Severe intra- and periventricular hemorrhage: role of arteriolosclerosis related to maternal smoke.

OBJECTIVE: The authors aimed to describe the atherosclerotic lesions of the cerebral arterioles as a substrate of their rupture and bleeding. METHODS: The study was performed on the brain of nine Caucasian fetal victims of intra- and periventricular hemorrhage, all grade IV, and nine control cases. RESULTS: In the nine victims of hemorrhage, the arteriolar wall structure was altered, focally transformed into a deposit of amorphous eosinophilic material. Such changes often affected the full thickness of the wall causing rupture and hemorrhage. In eight of these cases and in two victims of the control group, the mothers were heavy cigarette smokers (15-20 cigarettes/day) before and during pregnancy. CONCLUSION: The authors conclude that intra- and periventricular hemorrhage can be ascribed to the toxic effects of prenatal absorption of nicotine.

Primary Cardiac Fibroma and Cardiac Conduction System Alterations in a Case of Sudden Death of a 4-month-old Infant.

A 4-month-old female infant considered to be in good health died suddenly and unexpectedly. Post- mortem examination was requested, with clinical diagnosis of sudden infant death syndrome. At autopsy the infant was described in good health. Histo- logical examination of the heart found a cardiac fibroma compressing the atrio-ventricular node and the examination of the cardiac conduction system showed an accessory fiber of Mahaim (nodo-ventricular) and cartilaginous metaplasia of the cardiac fibrous body. Probably the concomitant presence of cardiac conduction system abnormalities and a septal fibroma, compressing the atrio-ventricular node, could have an important role in causing the sudden death.

Sudden death of an infant with cardiac, nervous system and genetic involvement--a case report.

We present a case of sudden death of a 1-month-old male infant with heart, brainstem and genetic polymorphism involvement. Previously considered quite healthy, the child died suddenly and unexpectedly during sleep. The autopsy protocol included an in-depth anatomopathological examination of both the autonomic nervous system and the cardiac conduction system, and molecular analysis of the serotonin transporter gene promoter region, in which a specific genetic condition seems to be associated with sudden infant death. Histological examination revealed the presence of congenital cardiac alterations (hypertrophic cardiomyopathy and an accessory Mahaim fiber in the cardiac conduction system), severe hypodevelopment of all the raphe nuclei and a heterozygous genotype L/S related to the serotonin transporter gene. The sudden death of this infant was the unavoidable outcome of a complex series of congenital anomalies, each predisposing to SIDS. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/3480540091031788.

Neuropathology of the area postrema in sudden intrauterine and infant death syndromes related to tobacco smoke exposure.

The area postrema is a densely vascularized small protuberance at the inferoposterior limit of the fourth ventricle, outside of the blood-brain barrier. This structure, besides to induce emetic reflex in the presence of noxious chemical stimulation, has a multifunctional integrative capacity to send major and minor efferents to a variety of brain centers particularly involved in autonomic control of the cardiovascular and respiratory activities. In this study we aimed to focus on the area postrema, which is so far little studied in humans, in a large sample of subjects aged from 25 gestational weeks to 10 postnatal months, who died of unknown (sudden unexplained perinatal and infant deaths) and known causes (controls). Besides we investigated a possible link between alterations of this structure, sudden unexplained fetal and infant deaths and maternal smoking. By the application of morphological and immunohistochemical methods, we observed a significantly high incidence of alterations of the area postrema in fetal and infant victims of sudden death as compared with age-matched controls. These pathological findings, including hypoplasia, lack of vascularization, cystic formations and reactive gliosis, were related to maternal smoking. We hypothesize that components from maternal cigarette smoke, particularly in pregnancy, could affect neurons of the area postrema connected with specific nervous centers involved in the control of vital functions. In conclusion, we suggest that the area postrema should be in depth examined particularly in victims of sudden fetal or infant death with smoker mothers.

Developmental alterations of the prefrontal cerebral cortex in sudden unexplained perinatal and infant deaths.

The aim of this study was to investigate the developmental patterns of the human prefrontal cortex involved in breathing control in a wide cohort of fetal and infant death victims, aged from the 22(nd) gestational week to 10 months of life, and to evaluate whether morpho-functional disorders are present in this specific cortical area in victims of sudden unexplained death. A further aim was to determine whether prenatal absorption of nicotine could also affect the maturational processes of the prefrontal cortex. A pronounced radial organization of the cerebral wall was evident from the 26(th) gestational week. By 36 gestational weeks this columnar structure disappeared, coinciding with the formation of a laminar cyto-architecture. The mature cortex, observable from the 4(th) month of life, was organized horizontally into six laminae. In 33% of the sudden death victims the prefrontal cortex showed morphological alterations with anomalous laminar patterns and delayed neuronal maturation. A significant correlation with prenatal cigarette exposure was found.