X-linked aqueductal stenosis.

A family is reported in which eight members of one generation were affected by the syndrome hydrocephalus with aqueductal stenosis. With the exception of one child who lived for several weeks, they all died at or within 10 days of birth. Autopsy of a pair of affected twins showed marked stenosis of the aqueduct of Sylvius with fusion of the lamina quadrigemina. There were no signs of previous or present inflammatory changes or neoplasia. All the affected individuals were males, and the familial and pathological data presented support the concept that aqueductal stenosis in this family was due to an X-linked gene, and may have a developmental origin.     

X-linked recessive aqueductal stenosis without macrocephaly

A normocephalic, severely retarded boy with a family history suggesting aqueductal stenosis was found by computerized tomography to have aqueductal stenosis. His parents' concurrent pregnancy was monitored by ultrasonography and amniocentesis; these disclosed a male fetus which developed marked hydrocephalus after the 20th week. The pregnancy was terminated and an autopsy of the fetus demonstrated several major CNS malformations in addition to a very narrowed aqueduct. This case illustrates the diffuse CNS disease present in at least some cases of X-linked aqueductal stenosis (XLAS) and the importance of considering this variable syndrome in normocephalic, non-dysmorphic mentally retarded males. Important aspects of the prenatal diagnosis of XLAS are also illustrated.     

A novel low-profile ventriculoamniotic shunt for foetal aqueductal stenosis

This study proposed a novel ventriculoamniotic shunt device for foetal aqueductal stenosis treatment fabricated with 3Fr or 4Fr size catheters that have a longitudinal bending stiffness with kink resistance, sufficient luminal area for cerebrospinal fluid drainage and capacity for valve integration. Computational flow dynamics studies were carried out to optimise the device design, including size of the lumen and length of the device. An in vitro pressure and flow rate measurement test circuit was constructed to assess the high pressure relieving functionality of draining cerebrospinal fluid from foetal brain. Additionally, a resistance force measurement test platform was built to quantitatively evaluate the anchor performance of various geometric designs. The valve functionality was qualitatively evaluated through the visualisation of the flow patterns in the amniotic sac with injected red coloured fluid under stereomicroscopy. These in vitro results demonstrate the feasibility of the ventriculoamniotic shunt device designed for placement in the foetal brain.     

Urofacial syndrome associated with hydrocephalus due to aqueductal stenosis

The urofacial syndrome is an autosomal recessive disorder of distorted facial expression and neurogenic bladder with resultant urogenital tract damage. We report on an 8-year-old boy of consanguineous Arab parents with inverted facial expression upon laughing and renal changes as a consequence of a neurogenic bladder in addition to hydrocephalus due to stenosis of the aqueduct of Sylvius. We suggest that the association is not fortuitous and probably widens the spectrum of urofacial syndrome or represents a distinct entity mimicking the urofacial syndrome.     

Prenatal diagnosis of X linked hydrocephalus without aqueductal stenosis.

The outcome of four successive pregnancies in a woman heterozygous for X linked hydrocephalus is described. The last two were scanned by ultrasound. In one, a good prognosis was given; the fetus was male but there was no evidence of dilated cerebral ventricles. In the other, hydrocephalus was diagnosed. The absence of aqueductal stenosis in this case supports the hypothesis that in this X linked condition communicating hydrocephalus is the primary defect and aqueductal stenosis is secondary.     

Brief clinical report: aqueductal stenosis leading to hydrocephalus--an unusual manifestation of neurofibromatosis

Two brothers and an unrelated male with neurofibromatosis (NF) developed hydrocephalus in childhood. Aqueductal stenosis (AS) was demonstrated by ventriculography and required shunt operation. Genetic counselors had to decide whether to invoke an X-linked gene for AS or whether AS could be caused by the NF mutation. Reports of 13 patients of both sexes with AS and NF suggest that AS with resulting hydrocephalus may be a rare manifestation of the NF gene. AS should be looked for in young NF patients with signs of hydrocephalus or with neurologic abnormalities.     

Enamel hypoplasia,bilateral cataracts,and aqueductal stenosis: A new syndrome?

We report on a 12-year-old girl who presented with generalized enamel hypoplasia, cataracts, and enlargement of the cerebral ventricles secondary to aqueductal stenosis. Previously described syndromes of enamel defects with or without cataracts were excluded on the basis of clinical criteria and appearance of the dentition. Metabolic conditions which could have caused cataracts were excluded clinically and by biochemical tests. The combination of signs in this patient may represent a new syndrome. © 1995 Wiley-Liss, Inc.     

Secondary amenorrhea caused by hydrocephalus due to aqueductal stenosis : report of two cases

Amenorrhea is rarely presented as a manifestation of endocrinological disturbances in patients of chronic hydrocephalus. We describe two cases of secondary amenorrhea caused by hydrocephalus due to aqueductal stenosis. Two female patients of age 30 and 20 yr presented with amenorrhea and increasing headache. Magnetic resonance images revealed marked, noncommunicating hydrocephalus without any tumorous lesion. In one patient, emergent extraventricular drainage was necessary because of progressive neurological deterioration. Each patient underwent surgical intervention for the hydrocephalus-ventriculoperitoneal shunt and endoscopic third ventriculostomy. Both resumed normal menstruation continuing so far with further normal menstrual bleeding. These two cases and others reported in the literature indicated that the surgical intervention for hydrocephalus resolves amenorrhea in all the cases of amenorrhea due to hydrocephalus. The suspected role of the surgery is the correction of increased intracranial pressure, which is an important pathogenetic factor in the development of amenorrhea.     

X-linked hydrocephalus

We report on a family with X-linked hydrocephalus: progressive increase in head circumference (OFC) led to the diagnosis in 3 patients; however, in 5 with normal OFC, the initial diagnosis had been "nonspecific" mental retardation, until identification of relatedness between 3 macrocephalic boys suggested segregation of a major Mendelian gene. Moderate to severe hydrocephaly was present in all macrocephalic patients and in 3 of the 5 with normal OFC, but CT-scan of the brain did not show aqueductal stenosis in any of them. We stress the importance of a brain CT-scan in every male with "nonspecific" mental retardation, especially in cases with X-linked inheritance, because confirmation of X-linkage has important genetic counseling consequences.     

X-linked hydrocephalus

We report on a family with X-linked hydrocephalus: progressive increase in head circumference (OFC) led to the diagnosis in 3 patients; however, in 5 with normal OFC, the initial diagnosis had been “nonspecific” mental retardation, until identification of relatedness between 3 macrocephalic boys suggested segregation of a major Mendelian gene. Moderate to severe hydrocephaly was present in all macrocephalic patients and in 3 of the 5 with normal OFC, but CT-scan of the brain did not show aqueductal stenosis in any of them. We stress the importance of a brain CT-scan in every male with “nonspecific” mental retardation, especially in cases with X-linked inheritance, because confirmation of X-linkage has important genetic counseling consequences.     

X-linked agammaglobulinemia

Conclusions The identification of the gene responsible for XLA has made it possible to clarify the clinical and laboratory findings in this disorder. It has markedly improved our ability to provide informative genetic counseling for affected families and it has helped unmask disorders that are clinically similar to XLA but genotypically different. However, many significant questions remain unanswered. What are the factors that influence the severity of disease and can we manipulate these factors to the benefit of the patient? As an increasing proportion of patients with XLA reach middle age and old age, are there previously unidentified complications that we should be aware of? What are the biological mechanisms by which mutations in Btk result in a failure of B-cell development and are these mechanisms different at different stages of B-cell differentiation? The long term goal of patients with XLA, their families, and the physicians who provide care for them is improved treatment for this disorder. Perhaps it is not unreasonable to hope that we are on the brink of entering the molecular therapeutic are of immunology.     

X-linked idiopathic thrombocytopenia

A family is described in which the incidence of thrombocytopenia suggested transmission by an X-linked gene. The condition carries a good prognosis. Comparison with previous similar reports suggests that the disorder is phenotypically distinct from the Wiskott-Aldrich syndrome.     

X-linked dilated cardiomyopathy

To study the inheritance of idiopathic dilated cardiomyopathy, we investigated a large kindred in which 11 young male members had definite or possible evidence of the disorder. The five affected males for whom we had complete clinical data survived for 5 to 12 months after the onset of symptoms, which occurred early in life (ages 15 to 21 years). In six other males, clinical data were incomplete but suggested possible cardiomyopathy. Three mothers of affected males were given a diagnosis of definite, and two of possible, late-onset dilated cardiomyopathy. These women presented in their 40s with atypical chest pain, and progressive congestive heart failure developed gradually over a period of 10 or more years. X-linked inheritance of dilated cardiomyopathy is suggested in this family by the early onset in males, late onset in females, and no evidence of male-to-male transmission. The late onset of the disease in females, in contrast to the early onset in hemizygous males, is compatible with heterozygosity for the mutant allele. Since most cases of genetically lethal X-linked syndromes appear to be sporadic, for every case of "idiopathic" dilated cardiomyopathy in which X-linked inheritance can be confirmed from family information, it is possible that there are several nonfamilial cases due to a mutation at the same locus.