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At least 19 recordsLinked to original sources

Central nervous system malformations in ethylmalonic encephalopathy.

Central nervous system malformations have been reported in a number of inherited enzyme defects. Ethylmalonic encephalopathy, an organic aciduria of unknown pathogenesis, has not been reported previously in association with brain or spinal cord malformations. We report on 2 sibs with confirmed ethylmalonic encephalopathy and malformations of the central nervous system; one with tethered cord, the other with cerebellar tonsillar ectopia (Chiari I malformation).

Abnormalities, Multiple↗

Molecular genetic classification of central nervous system malformations.

Traditional schemes of classifying nervous system malformations are based on descriptive morphogenesis of anatomic processes of ontogenesis, such as neurulation, neuroblast migration, and axonal pathfinding. This proposal is a first attempt to incorporate the recent molecular genetic data that explain programming of development etiologically. A scheme based purely on genetic mutations would not be practical, in part because only in a few dysgeneses are the specific defects known, but also because several genes might be involved sequentially and many genes inhibit or augment the expression of others. The same genes serve different functions at different stages and are involved in multiple organ systems. Some complex malformations, such as holoprosencephaly, result from several unrelated defective genes. Finally, a pure genetic classification would be too inflexible to incorporate some anatomic criteria. The basis for the proposed scheme is, therefore, disturbances in patterns of genetic expression; polarity gradients of the axes of the neural tube (eg, upregulation or downregulation of genetic influences); segmentation (eg, deletions of specific neuromeres, ectopic expression); mutations that cause change in cell lineage (eg, dysplastic gangliocytoma of cerebellum, myofiber differentiation within brain); and specific genes or molecules that mediate neuroblast migration in its early (eg, filamin-1), middle (eg, LIS1, double-cortin), or late course (eg, reelin, L1-CAM). The proposed scheme undoubtedly will undergo many future revisions, but it provides a starting point using currently available data.

Central Nervous System↗

Pulsatile tinnitus associated with congenital central nervous system malformations.

Pulsatile tinnitus as a manifestation of congenital central nervous system malformations has not been previously described. We present two patients with type I Arnold-Chiari malformation and one patient with congenital stenosis of the sylvian aqueduct with pulsatile tinnitus. Pulsatile tinnitus in these patients is believed to be secondary to increased intracranial pressure. Tinnitus subsided in one patient with Arnold-Chiari malformation after suboccipital decompression. The other two patients declined surgery. Audiologic and radiologic findings are presented, and our diagnostic algorithm for pulsatile tinnitus is described. The pathophysiology of pulsatile tinnitus can be a manifesting symptom in some patients with congenital central nervous system malformations.

Adult↗

Integrative classification of morphology and molecular genetics in central nervous system malformations.

We propose a scheme to classify central nervous system (CNS) malformations that integrates morphology and genetics by using patterns of genetic expression as its basis. The precise genetic mutations are not necessary to know in all cases. The premises of this classification are (1) genetic expression in the neural tube follows gradients in the axes that are established at the time of gastrulation: vertical (dorsoventral and ventrodorsal); rostrocaudal; mediolateral. (2) Overexpression in one of these gradients generally results in duplication or hyperplasia of structures, or ectopic segmental (i.e., neuromeric) expression. (3) Underexpression in a gradient generally results in hypoplasia, noncleavage in the midline of paired structures or segmental deletion of neuromeres. These gradients may also affect the formation and migration of neural crest tissue, affecting non-neural structures such as the face in the case of the mesencephalic neural crest, or induction of paraxial mesodermal in the posterior fossa. Additional criteria of the new classification allow for other genetic influences on developmental processes, such as cellular lineage, exemplified by tuberous sclerosis, and hemimegalencephaly. It is essential that the CNS be considered as a whole and classification not be regionalized, as to the cerebral cortex, because the limit of the rostrocaudal gradient may account for variability in clinical manifestations.

Central Nervous System↗

[Central nervous system malformations in a Clinical Hospital of Universidad de Chile and in Chilean maternity hospitals that participated in the Latin American Collaborative Study of Congenital Malformations (ECLAMC)].

BACKGROUND: In Chile, the rates of central nervous system congenital malformations at birth remain high, when compared with the rest of the world. AIM: To report the rates of central nervous system congenital malformations in Chilean hospitals. MATERIAL AND METHODS: Using the ECLAMC protocol, every malformed newborn or stillbirth, weighing more than 500 g at birth is registered using a standard protocol, and the next non malformed child of the same sex born in the same hospital is assigned as control. RESULTS: The rates of central nervous system congenital malformations are higher at the University of Chile Clinical Hospital than in the rest of Chilean hospitals or Latin American Hospitals. There are significantly higher rates of anencephalia in Concepcion and spina bifida in Valdivia, Rancagua and Concepcion. In the University of Chile Clinical Hospital, global annual rates have a negative slope of -0.0259 per 1000 born alive, with a correlation coefficient of -0.125 (p < 0.05). The slope is positive among children born alive, with an annual rate increase of 0.071. Among stillbirths, the slope is -0.47 per 1000 born alive. Sixty two percent of malformed children were female. Among children with neural tube defects, 30% had a malformed relative and, of these, 66% had the same malformation. CONCLUSIONS: Family clustering of neural tube defects, supports the influence of a genetic factor influencing their appearance.

Adolescent↗

Genetic advances in central nervous system malformations in the fetus and neonate.

Malformations of the central nervous system (CNS) are commonly encountered by the pediatric neurologist when called to evaluate a fetus or newborn. Such malformations may be isolated or appear as part of a genetic syndrome. In the past few years there have been great advances in identifying the genes and genetic alterations for many isolated CNS malformations and syndromes with CNS malformations. Therefore, it is important to look for associated anomalies in any infant with a CNS malformation, as well as consideration of the rest of the family. We have chosen four malformations (holoprosencephaly, hydrocephalus, lissencephaly, and schizencephaly) to serve as a paradigm for genetic malformations of the CNS. Understanding the underlying genetic etiology of a disorder allows us to give more accurate recurrence risk counseling, to better estimate potential complications, and to better manage the patient's care. As research continues, additional malformations and syndromes will be understood on the genetic level, and combining this genetic information with neurologic understanding will translate into better medical care for the patient.

Adult↗

Mental retardation, distinct craniofacial dysmorphism, and central nervous system malformation: confirmation of a syndrome.

We present a child with severe mental retardation, a central nervous system malformation, signs of ectodermal dysplasia, and a distinct craniofacial dysmorphism. Similar but less pronounced craniofacial features were present in the mildly mentally retarded mother. This observation confirms a previous report of a boy with the same MCA-MR syndrome and suggests X linked or autosomal dominant inheritance.

Adult↗

Central nervous system malformations in a perinatal/neonatal autopsy series.

Congenital malformations of the central nervous system (CNS) are among the most common anomalies, but data on the incidence of CNS malformations in autopsy populations are scant. We examined 4122 autopsies between the years 1958 and 1995. There were 363 cases (8.8%) with CNS malformations; 235 were neonates and 128 stillborns. The overall gender ratio was 1:1, although more male neonates and more female stillborns had malformations. The body weights ranged from 24 to 6440 g. Neural tube defects were the most common types of malformations (45.5%) and included anencephaly, meningoencephalocele, meningocele/meningomyelocele, craniospinal rachischisis, and spina bifida occulta. The incidences of other malformations were: congenital hydrocephalus (12.4%), neuronal/glial proliferation disorders such as micro- and macrocephaly (8.8%), neuronal migration disorders (8.8%), prosencephalon growth disorders such as holoprosencephaly and arhinencephaly (8.5%), abnormalities of the midline structures such as agenesis of corpus callosum (4.1%), developmental cysts (3.3%), cerebellar malformations (3%), and vascular malformations (2%). Miscellaneous malformations (3%) consisted of acephalia in four cases with twin reversed arterial perfusion (TRAP), two cases of hydranencephaly, and four cases of rare degenerative and metabolic encephalopathies.

Autopsy↗

Molecular genetics of central nervous system malformations.

INTRODUCTION: Each of the processes involved in the development of the central nervous system is under genetic control and some mutations are responsible for severe malformations. For example, holoprosencephaly is associated with HPE genes, hydrocephalus with L1-CAM and lissencephaly with LIS-1. DISCUSSION: Molecular genetics has brought new insights into the etiology and pathogenesis of nervous system malformations and has provided new tools for accurate prenatal diagnosis.

Amniocentesis↗

High incidence of central nervous system malformations associated with marked parental consanguinity in an Israeli Arab community.

It is common among Israeli Arabs who live in villages to prefer consanguineous marriages, particularly among first cousins. In addition, such villages are populated by a few (< 20) original families, and inter-family/inter-village marriages are infrequent. The purpose of this study was to examine the incidence of congenital malformation of the central nervous system associated with such "consanguinity" in Taibe, a large Arab village, 30 km from Tel Aviv. Six hundred and ten families were prospectively ascertained through infants who were routinely seen in the local "Well Baby Clinics". A significant increase in the incidence of major malformations was noted in relation to the closeness of the parental relationship. For the index cases group, the prevalence of individuals with major malformations was 5.8% in the product of inter-village marriages, 8.3% in the intra-village non-related matings, 15.1% in the distant consanguineous group, and up to 15.8% in the progeny of first-cousin marriages (P < 0.001). Malformations of the central nervous system consisted of 1/3 to 1/2 of the total malformations in the consanguineous group versus less than 1/5 in the non-consanguineous groups. The study demonstrates a marked high rate of consanguineous marriages, the effect of which leads to a marked increase in major malformations and especially those of the central nervous system. This requires a unique genetic counseling approach.

Adult↗

Outcome of children with prenatally diagnosed central nervous system malformations.

OBJECTIVE: To study the outcome of pregnancies with a prenatally diagnosed central nervous system (CNS) malformation. METHODS: Leiden University Medical Centre is a tertiary referral center for fetal ultrasound and invasive prenatal diagnosis. Maternal and neonatal records of prenatally diagnosed CNS malformations were retrospectively reviewed over a 6-year period (1993-1998). Information on current development of surviving children was obtained by contacting the care-giving pediatric neurologist. RESULTS: During the study period 124 fetuses were diagnosed with a CNS malformation. Data on pregnancy and delivery were available for 118 pregnancies. Additional malformations were present in 47% of fetuses (55/118). A total of 46% of pregnancies (54/118) were terminated, and 15% (18/118) ended in spontaneous intrauterine death. A total of 39% of pregnancies (46/118) resulted in live birth, and 29 of the infants were still alive at the age of 3 months. One child was lost to follow-up, one infant died at the age of 4 months, and two children died at the age of 3 years. Psychomotor development of the remaining 25 children was normal for five, slightly disabled for seven, moderately disabled for five and severely disabled for eight. CONCLUSION: Due to the high rate of termination of pregnancy and to the frequent association with other anomalies, the survival rate of pregnancies in which a CNS defect had been diagnosed prenatally was only 25%. More than 50% of surviving children were moderately or severely disabled.

Adolescent↗

Congenital central nervous system malformations and vinyl chloride monomer exposure: a community study.

Incidence rates for central nervous system (CNS) malformations in infants born to residents of Kanawha County, West Virginia, 1970-1974, were significantly higher than comparable United States rates during those years. Since Kanawha County contains a polyvinyl chloride (PVC) polymerization plant, a case-control study was conducted on the possible relationship between the occurrence of CNS defects and parental occupational or residential exposure to vinyl chloride monomer emissions from this plant. No relationship with parental occupation was found. While a tendency was noted for residences of case families to be located in an area northeast of the plant, this observation did not entirely correlate with existing data on local patterns of wind direction and air pollution.

Abnormalities, Drug-Induced↗