Expanding the phenotype of COL4A1-related disorders-Four novel variants

OBJECTIVE

COL4A1 variant causes severe central nervous system (CNS) anomalies, including hydranencephaly. However, the pathogenic mechanism underlying the COL4A1 phenotype remains unclear. Here, we report de novo COL4A1 variants in four Japanese patients with typical or rare CNS involvement and exhibiting diverse phenotypes.

METHODS

We identified and enrolled four patients with white matter abnormalities and cerebral structural defects suggestive of cerebrovascular disease. Genetic analysis was performed using panel sequencing.

RESULTS

All the patients were perinatally asymptomatic during the infantile period but exhibited developmental delay and growth retardation later. All the patients exhibited CNS symptoms, including psychomotor disability, spastic paralysis, and epilepsy. Brain magnetic resonance imaging revealed hydranencephaly (n = 1), ventriculomegaly (n = 4) associated with cerebral hemorrhage, and atretic encephalocele (n = 1). Three patients had developed congenital cataract, while two had hematuria. We identified two COL4A1 missense variants [exon32:c.2555G > A p.(Gly852Asp), exon40:c.3407G > A p.(Gly1136Asp)] and two in frame variants [exon32:c.2603_2609delinsATCCTGA p.(Ala868_Gly870delinsAspProGlu), exon36:c.3054delinsTGTAGAT p.(Leu1018delinsPheValAsp)]. The in frame variants were associated with severe CNS anomalies, hydranencephaly, and severe ventriculomegaly. Atretic encephalocele has never been reported in individuals with COL4A1 variants.

CONCLUSIONS

Our findings suggest that COL4A1 variants cause variable CNS symptoms. Association between clinical phenotypes and each COL4A1 variant would clarify their underlying etiologies.

Hydranencephaly: Clinical Features and Survivorship in a Retrospective Cohort

OBJECTIVE

Hydranencephaly is a congenital central nervous system disorder characterized by the complete or near-complete absence of the cerebral cortex and basal ganglia. Because of its rarity, data on the clinical features and survivorship remain sparse. We aim to determine the clinical features and survivorship of a cohort of patients with hydranencephaly.

METHODS

We performed a retrospective cohort study of all patients diagnosed with hydranencephaly at our institution from 2008 to 2018. Data on demographics, clinical features, presence of comorbidities, surgical operations performed, and status on last follow-up were collected. Survival curves were generated using Kaplan-Meier analysis.

RESULTS

Fifty patients were included in the cohort, who had a median age at diagnosis of 4 months and a female predilection. The most common clinical manifestations were macrocephaly (92%) and seizures or myoclonic movements. Infection was present in 36% of cases, endocrinopathies in 22%, dysmorphisms in 20%, and cardiac disease in 8%. Twenty patients underwent shunt insertion, with half developing a postoperative complication at a mean follow-up of 14.9 months. The median survival of the cohort was not reached at 7.5 years. Among the patients with follow-up, characteristics were similar between the surgical and nonsurgical groups, except for the greater incidence of infections in the nonsurgical group. The survival curves among the groups were significantly different, with a hazard ratio of 3.731 in the nonsurgical group.

CONCLUSIONS

In this large single-center retrospective cohort of patients with hydranencephaly, novel findings are presented regarding the clinical manifestations and survivorship of this condition.

Unveiling what is absent within: illustrating anesthetic considerations in a patient with hydranencephaly - a case report

BACKGROUND

Hydranencephaly is a rare and debilitating congenital condition in which most anesthesiologists are unfamiliar. Primary surgical treatment involves CSF diversion, though other palliative procedures requiring anesthesia are often required. With medical advancements and a resulting prolonged life expectancy, caring for these patients is becoming more routine.

CASE PRESENTATION

We follow an infant with hydranencephaly over three different procedures requiring anesthesia from 5 months of age to 2 years, highlighting the various anesthetic considerations.

CONCLUSIONS

Anticipation of difficult positioning, deliberate airway management, and attention to anesthetic recovery were all necessary to safely care for this patient. An understanding of the challenges this particular condition poses will help anesthesiologists provide the most safe and effective care when encountering these patients.

Management and problems of prolonged survival with hydranencephaly in the modern treatment era

PURPOSE

Hydranencephaly is a rare condition that occurs during embryogenesis after neurogenesis and is characterized by the near complete absence of the cerebral hemispheres. In general, patients with hydranencephaly have been considered to have a markedly reduced life expectancy. We present 4 patients with hydranencephaly who have survived for over 5 years. The management and problems encountered in these cases are discussed.

METHODS

A retrospective review was conducted at our institution. Medical charts and radiographic studies were reviewed. Data including age at follow-up, sex, clinical complications, and surgical procedures were recorded.

RESULTS

Six patients were radiologically diagnosed with hydranencephaly during the period from January 2000 to December 2012. Two patients were excluded from our study: one because of death from pneumonia at 1 year of age and another because of transfer to another hospital. Four patients (3 males and 1 female) were included in the analysis. All 4 patients underwent ventriculoperitoneal shunt (VPS) placement and shunt revision. VPS infection occurred in 3 of 4 cases, and bloody cerebrospinal fluid (CSF) was observed in 2 of 4 cases. One patient underwent successful choroid plexus cauterization (CPC) and shunt removal after shunt infection.

CONCLUSIONS

Prolonged survival with hydranencephaly is not unusual in the modern treatment era. CSF shunt problems, such as recurring shunt malfunction and shunt infection, represent one of the major problems, and avoiding CSF shunt with CPC is particularly desirable in patients with hydranencephaly.

The Benefits of a Guideline on Safe Termination of Pregnancy for Legal Indications: An Illustrative Case Report of a Hydranencephaly

After years of the worsening burden of unsafe abortion and attendant morbidities and mortalities in Nigeria, a National Guideline on the Safe termination of pregnancy for legal indications was enunciated. This report presents and discusses an illustrative case of a hydranencephaly that benefited from it. A 43-year old multipara was informed during routine ultrasonography at booking for antenatal care, at 16 weeks of gestation, of a major defect in her baby and advised to meet her physician. Following a repeat high- resolution ultrasonography and discussions between the Obstetricians, Neurosurgeon, and Ultrasonologist, the woman was counseled on the diagnosis. At her insistence and provision of written consent, medical abortion with Mifepristone and Misoprostol was successfully instituted.

Hydranencephaly complicated by central diabetes insipidus: report of two cases and systematic review of literature

PURPOSE

Hydranencephaly is a congenital condition characterized by the complete or near-complete absence of the cerebral cortex and basal ganglia, while central diabetes insipidus (CDI) is a condition characterized by the inability to concentrate urine due to a deficiency in antidiuretic hormone (ADH). CDI is known to occur in midline congenital malformations such as holoprosencephaly and septo-optic dysplasia, but its association with hydranencephaly is less well-established.

METHODS

We reported two cases of hydranencephaly complicated by CDI. We also performed a systematic review of the SCOPUS and PubMed databases for case reports and case series of patients with hydranencephaly and CDI, and compiled data on the clinical features and treatment options.

RESULTS

Seven cases of hydranencephaly complicated by CDI were identified from the systematic review in addition to the two cases reported here, resulting in a total of nine cases. The patients' age ranged from 4 days to 4 years, and there was a female sex predilection (3.5:1). Patients most commonly presented with macrocephaly, developmental delay, and seizures, with dysmorphic features noted in 33%. In addition to CDI, other endocrinologic derangements included hypothyroidism (22%), hypocortisolemia (22%), and panhypopituitarism (22%). CDI was treated using sublingual or oral desmopressin while hypopituitarism was treated with the appropriate hormone replacement therapy. Insertion of a ventriculoperitoneal (VP) shunt was reported in 44% of cases.

CONCLUSION

The case reports and systematic review suggest a previously unknown association between hydranencephaly and CDI. Clinicians managing cases of hydranencephaly are advised to have a high index of suspicion for CDI in patients presenting with the characteristic signs and symptoms.

An unusual presentation of bobble-head doll syndrome in a patient with hydranencephaly and Chiari 3 malformation

Bobble-head doll syndrome is a rare movement disorder that is usually associated with lesions involving the third ventricle. It is characterised by stereotypical rhythmic up-and-down or side-to-side head movements. The pathophysiology and anatomical basis for this unusual manifestation is still a subject of intense scrutiny. The syndrome has never been described in a patient with both hydranencephaly and Chiari type 3 malformation. We describe a 2-year-old female patient who presented with congenital hydrocephalus, an occipital encephalocele and rhythmic bobbling of the head. Imaging investigation revealed a Chiari type 3 malformation and hydranencephaly. The patient was taken to theatre for a ventriculoperitoneal shunt insertion, and at day 3 post operatively, the patient had a markedly decreased head circumference and a decrease in the frequency of the bobbling of the head. A further review at 2 weeks showed that the bobbling of the head had ceased. Although the pathophysiology of bobble-head doll syndrome is yet to be fully understood, there has been postulation of either a third ventricular enlargement or a cerebellar dysfunction to explain bobble-head doll syndrome. Our case illustrates that the pathophysiology is most likely multifactorial as illustrated by the fact that by just addressing the high intracranial pressure with a shunt was sufficient to treat the condition.

Fowler syndrome and fetal MRI findings: a genetic disorder mimicking hydranencephaly/hydrocephalus

Fetal ventriculomegaly is a common referral for prenatal MRI, with possible etiologies being hydrocephalus and hydranencephaly. The underlying cause of hydranencephaly is unknown, but many have suggested that the characteristic supratentorial injury is related to idiopathic bilateral occlusions of the internal carotid arteries from an acquired or destructive event. Fowler syndrome is a rare genetic disorder that causes fetal akinesia and a proliferative vasculopathy that can result in an apparent hydranencephaly-hydrocephaly complex. On prenatal imaging, the presence of significant parenchymal loss in the supratentorial and infratentorial brain is a clue to the diagnosis, which should prompt early genetic testing.

Choroid plexus cauterization on treatment of hydranencephaly and maximal hydrocephalus

INTRODUCTION

The standard treatment for hydranencephaly and maximal hydrocephalus consists of inserting shunts, although complications frequently occur. Choroid plexus cauterization (CPC) is an alternative, but its long-term efficacy and the factors associated with the success and failure of controlling head circumference (HC) are not well defined.

OBJECTIVE

This study aims to evaluate the long-term efficacy and factors related to the success rate of CPC in the treatment of hydranencephaly and maximal hydrocephalus.

METHOD

Forty-two children with maximal hydrocephalus and hydranencephaly underwent CPC from 2006 to 2014 and were retrospectively evaluated. Children with less than 3 months of follow-up were excluded. The long-term efficacy and success rate of possible variables (i.e., sex, type of malformation, type of surgery performed, treatment hospital, age, and HC at the time of surgery and birth) were evaluated.

RESULTS

Thirty-four children were considered for the effectiveness analysis. Treatment was successful in 24 children (70.6%), and failure occurred in 10 children (29.4%). Failure was detected soon after the endoscopic procedure (average 116 days). There was no difference in effectiveness when comparing the age at the moment of surgery (p = 0.473), type of malformation (p = 1), HC at birth (0.699), and HC at the time of surgery (p = 0.648). The surgical death rate was 7.14%.

CONCLUSION

Endoscopic CPC was a valid procedure used to treat hydranencephaly and maximal hydrocephaly, and it was effective in 70.6% of cases, with an average follow-up period of 32 months. When failures occurred, they occurred early. None of the analyzed variables interfered with the success of the treatment.

A Case of Hydranencephaly in Which Ophthalmic Examinations Were Performed

Purpose

We performed ophthalmic examinations, including optical coherence tomography (OCT), on a case diagnosed with hydranencephaly.

Case Report

This case involved a female infant born at the gestational age of 35 weeks and 4 days, with the birth weight of 2,152 g, who was one of monochorionic diamniotic twins, and the identical twin died in utero at the gestational age of 24 weeks. After that, examination by fetal echo indicated that she had microcephaly and ventriculomegaly. Postnatal magnetic resonance imaging (MRI) of her head indicated microcephaly and significant enlargement of the lateral ventricle on both sides, with no obvious signs of elevated intracranial pressure. The brain parenchyma of both sides of the frontal lobe, parietal lobe, and occipital lobe had marked thinning, yet that of the temporal lobe, basal ganglia, thalamus, brain stem, and cerebellum had been maintained. Moreover, no obvious hematoma or neoplastic lesions were observed. Ophthalmic examinations indicated that both of her eyes had slight light reflex, attributed to optic nerve atrophy. Examination by use of a hand-held OCT system indicated a layered structure of the retina and thinning of the ganglion cell layer. Flicker electroretinogram (ERG) examination by use of a hand-held ERG system indicated an almost normal wave. However, no clear visual reaction was observed when she was 10 months old.

Conclusion

Our findings in this case of hydranencephaly revealed that even though the outer layer functions of the patient's retina were maintained, extensive damage to her cerebral cortex resulted in poor visual function.

A novel homozygous variant in SERPINH1 associated with a severe, lethal presentation of osteogenesis imperfecta with hydranencephaly

Osteogenesis imperfecta (OI) is a genetic disorder characterised by low bone mineral density resulting in fractures. 85-90% of patients with OI carry a variant in the type 1 collagen genes, COL1A1 and COL1A2, which follows an autosomal dominant pattern of inheritance. However, within the last two decades, there have been growing number of variants identified in genes that follow an autosomal recessive pattern of inheritance. Our proband is a child born in Mexico with multiple fractures of ribs, minimal calvarial mineralisation, platyspondyly, marked compression and deformed long bones. He also presented with significant hydranencephaly, requiring ventilatory support from birth, and died at 8days of age. A homozygous c.338_357delins22 variant in exon 2 of SERPINH1 was identified. This gene encodes heat shock protein 47, a collagen-specific chaperone which binds to the procollagen triple helix and is responsible for collagen stabilisation in the endoplasmic reticulum. There is minimal literature on the mechanism of action for variants in SERPINH1 resulting in osteogenesis imperfecta. Here we discuss this rare, previously unreported variant, and expand on the phenotypic presentation of this novel variant resulting in a severe, lethal phenotype of OI in association with hydranencephaly.

Hydranencephaly in a case of suspected infanticide

An abandoned fetus with suspicious skin injuries was found dead, lying on the grass of a garden, near a private house. Suspecting infanticide, the prosecutor ordered a medico-legal autopsy. The cause of death was identified as a congenital malformation of the central nervous system such as hydranencephaly, and infanticide was excluded.

Consciousness without cortex: a hydranencephaly family survey

AIM

Hydranencephaly is commonly taken to exemplify the developmental vegetative state, based largely on the assumption that radical loss of cortical tissue is incompatible with consciousness. The aim of the study reported here was to survey primary caregivers of children born with hydranencephaly for behavioural evidence indirectly informative about the conscious status of these children.

METHODS

The survey recruited 108 primary caregivers through a parent support group and was conducted online via a commercial survey hosting facility. As part of a more extensive questionnaire, participants answered 106 questions bearing on the environmental responsiveness, emotional reactivity, mood and agency of the child in their care.

RESULTS

The survey elicited a many-facetted and detailed set of caregiver answers and written observations regarding the child's behaviour. A conservative measure of agreement among respondents' answers yielded a generic portrait of the responsiveness and expressive behaviour of a hydranencephaly child.

CONCLUSION

The generic behavioural characteristics of hydranencephaly thus assessed are incompatible on multiple counts with the unconsciousness characteristic of the vegetative state. This bears on what is included under the concept of quality of life for children with hydranencephaly, and hence on appropriate forms of treatment and care in their case.

Endoscopic coagulation of choroid plexus in hydranencephaly

Hydranencephaly is a rare congenital disease defined as an absence of cerebral hemispheres with an intact thalamus, brain stem, and cerebellum. Generally, patients with hydranencephaly require cerebro-spinal fluid diversion due to progressive hydrocephalus. An excellent view of the choroid plexus and advancement of the neurosurgical endoscope were possible, leading to easy coagulation of the choroid plexus to balance cerebro-spinal fluid production without the use of a shunt device. We present this rare case and good treatment outcome from endoscopic coagulation of the choroid plexus.