An epidemiologic study of environmental and genetic factors in congenital hydrocephalus

Abstract

Risk factors were studied in 96 children with congenital hydrocephalus (CH) coming from 118,265 consecutive births of known outcome. Hydrocephalus with neural tube defects, intracranial tumors or secondary to brain atrophy were excluded. The prevalence of CH was 0.81 per thousand. Diagnosis was performed prenatally in 41 cases. Forty-three (44.8%) of the cases had hydrocephalus without other malformations (isolated hydrocephalus), 18 (18.7%) infants had recognized chromosomal or non-chromosomal syndromes and 35 children (36.4%) had multiple malformations. Each case was matched to a control. Weight and length at birth of children with hydrocephalus were less than in the controls (p < 0.001). The weight of the placenta was lower than in the controls (p < 0.05). The pregnancy with a hydrocephalic child was more often complicated by threatened abortion, polyhydramnios and oligohydramnios. The mothers of children with hydrocephalus and multiple malformations had used oral contraceptives during the first trimester of pregnancy more often than the mothers of the controls. No differences appeared between the mothers of children with CH and the controls for the other risk factors studied: parental age, parity, previous pregnancies, previous stillbirths, smoking, diabetes, epilepsy, X-rays, hypertension, fever "flu", medication and occupational exposure. There was an increase of parental consanguinity in the parents of our patients (6.2% v. 1.1%, p < 0.001) and first degree relatives had more non-cerebral malformations than the controls (7.3% v. 3.2%, p < 0.05).

Congenital hydrocephalus: Nosology and guidelines for clinical approach and genetic counselling

“…The differences between them however make them hard to compare: children with spina bifida were included or not, fetal deaths were taken into consideration or not, studies were population based or hospital based, and there were possible ethnic differences. In the studies since the 1980s, it is agreed that the incidence of congenital and infantile hydrocephalus (20 weeks gestational age-1 year) is 0.12 2.5 per 1000 live and stillbirths [22,46,61,63]. In a group of Swedish children with prenatal onset hydrocephalus [22], toxoplasmosis was an important causative factor; in the peri/postnatal group haemorrhage was the main determinant in preterm babies.…”

Epidemiology of Infantile Hydrocephalus in Saudi Arabia: Birth Prevalence and Associated Factors

“…Stoll et al [17]in their evaluation of 96 children with congenital hydrocephalus, which excluded cases of prenatal and perinatal infections and hemorrhage, reported a consanguinity rate of 6.6%. This was 6 times the frequency in their controls.…”

“…Despite this high rate of consanguinity among parents of children with hydrocephalus, only one sibling of a case had hydrocephalus. Stoll et al [17]concluded that parents of children with hydrocephalus are significantly more often related to each other than parents of controls. Varadi et al [18], suggested that couples who had one previous child with hydrocephalus, have a 4% incidence of hydrocephalus in a sibling.…”

Congenital hydrocephalus internus and aqueduct stenosis: aetiology and implications for genetic counselling

“…The frequency of congenital hydrocephalus internus (CHI) varies between 0.5 and 2.5 per 1000 newborns for dierent populations [4,11,13,22,25]. Retrospective studies report a low overall recurrence risk (0.6±1.4%) of CHI [4,7].…”