Prospective Evaluation of Kidney Disease in Joubert Syndrome

BACKGROUND AND OBJECTIVES

Joubert syndrome is a genetically heterogeneous ciliopathy associated with >30 genes. The characteristics of kidney disease and genotype-phenotype correlations have not been evaluated in a large cohort at a single center.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We evaluated 97 individuals with Joubert syndrome at the National Institutes of Health Clinical Center using abdominal ultrasonography, blood and urine chemistries, and DNA sequencing.

RESULTS

Patients were ages 0.6-36 years old (mean of 9.0±7.6 years old); 41 were female. Mutations were identified in 19 genes in 92 patients; two thirds of the mutations resided in six genes: TMEM67, C5orf42, CC2D2A, CEP290, AHI1, and KIAA0586. Kidney disease was detected in 30%, most commonly in association with the following genes: CEP290 (six of six), TMEM67 (11 of 22), and AHI1 (three of six). No kidney disease was identified in patients with mutations in C5orf42 (zero of 15) or KIAA0586 (zero of six). Prenatal ultrasonography of kidneys was normal in 72% of patients with kidney disease. Specific types of kidney disease included nephronophthisis (31%), an overlap phenotype of autosomal recessive polycystic kidney disease/nephronophthisis (35%), unilateral multicystic dysplastic kidney (10%), and indeterminate-type cystic kidney disease (24%). Early-onset hypertension occurred in 24% of patients with kidney disease. Age at ESRD (n=13) ranged from 6 to 24 years old (mean of 11.3±4.8 years old).

CONCLUSIONS

Kidney disease occurs in up to one third of patients with Joubert syndrome, most commonly in those with mutations in CEP290, TMEM67, and AHI1. Patients with mutations in C5orf42 or KIAA0586 are less likely to develop kidney disease. Prenatal ultrasonography is a poor predictor of kidney involvement in Joubert syndrome. Unilateral multicystic dysplastic kidney and autosomal recessive polycystic kidney disease-like enlarged kidneys with early-onset hypertension can be part of the Joubert syndrome kidney phenotype.

Differential diagnosis of leukokoria: radiologic-pathologic correlation

Leukokoria is an abnormal pupillary light reflection that usually results from an intraocular abnormality and is seen most often in children. One-half of the cases of childhood leukokoria are caused by retinoblastoma, a malignant tumor of immature retinoblasts that manifests in a normal-sized eye as a calcified mass, is often partially necrotic, and grows into the vitreous and through the choroid. Retinoblastoma enhances with contrast material and, unlike most tumors, may be darker than vitreous on T2-weighted images. When leukokoria is associated with microphthalmia, persistent hyperplastic primary vitreous (PHPV) (28% of cases) or retinopathy of prematurity (ROP) (5% of cases) should be considered. PHPV is a congenital, usually unilateral lesion that appears as a dense tubular mass extending from the lens to the retina along the course of the hyaloid canal. Hemorrhage from PHPV produces a subhyaloid (or subretinal) fluid collection, often with characteristic blood-fluid levels. ROP is bilateral and usually manifests in premature infants who received supplemental oxygen therapy. Coats disease (16% of leukokoria) is a sporadic unilateral idiopathic retinal telangiectasia that produces a lipoproteinaceous subretinal exudate leading to complete retinal detachment. The globe has normal size but increased attenuation and signal intensity from hemorrhage without calcification or enhancement. Toxocaral endophthalmitis (16% of leukokoria) is a granulomatous reaction to the parasite in the vitreous and uveoretinal coat. Retinal astrocytoma (3% of leukokoria), which manifests in a normal-sized globe, is an indolent benign neoplasm commonly associated with phakomatoses (usually tuberous sclerosis).

Absence of the greater sphenoid wing in neurofibromatosis type I: congenital or acquired: case report

unilateral absence of the greater wing of the sphenoid bone is a distinctive but uncommon manifestation of Type I neurofibromatosis, which has until now been regarded as a developmental anomaly of mesodermal origin. A computed tomographic scan was obtained in a 4-week-old infant with an abnormal left eye. The scan demonstrated an intact ipsilateral sphenoid bone, except for minor expansion of the medial end of the left superior orbital fissure. Another computed tomographic scan was obtained 6 years later, when the child had café-au-lait patches, axillary freckling, Lisch nodules, and left phthisis bulbi. This later scan showed typical sphenoid dysplasia. Much of the greater wing was absent, and the anterior temporal pole was displaced anteriorly. In this article, we discuss the implications of this case in terms of the cause of this condition and the diagnosis of Type I neurofibromatosis.

Prenatal unilateral cerebellar hypoplasia in a series of 26 cases: significance and implications for prenatal diagnosis

OBJECTIVE

To define imaging patterns of unilateral cerebellar hypoplasia (UCH), discuss possible pathophysiological mechanisms and underline the etiology and prognosis associated with these lesions.

METHODS

In this retrospective study we reviewed the charts of 26 fetuses diagnosed between 2003 and 2011 with UCH, defined by asymmetrical cerebellar hemispheres with or without decreased transverse cerebellar diameter. The review included analysis of the anatomy of the cerebellar hemispheres, including foliation, borders and parenchymal echogenicity, and of the severity of the hypoplasia. Data from clinical and biological work-up and follow-up were obtained.

RESULTS

Our series could be divided into two groups according to whether imaging features changed progressively or remained constant during follow-up. In Group 1 (n = 8), the progression of imaging features, echogenic cerebellar changes and/or hyposignal in T2*-weighted MR images were highly suggestive of ischemic/hemorrhagic insult. In Group 2 (n = 18), imaging features remained constant during follow-up; UCH was associated with abnormal foliation in three proven cases of clastic lesions, a cystic lesion was noted in three cases of PHACE (posterior fossa anomalies, hemangioma, arterial anomalies, cardiac abnormalities/aortic coarctation, eye abnormalities) syndrome and, in the remaining cases, UCH remained unchanged, with no imaging pattern typical of hemorrhage. In 24 cases the infant was liveborn and follow-up was continued in 23, for a mean period of 3 years. Among these, neurological complications were identified in seven (in one of seven (at a mean of 46 months) in Group 1 and in six of 16 (at a mean of 35 months) in Group 2). The surface loss of cerebellar hemisphere was > 50% in 19/24 fetuses and the vermis was clearly normal in appearance in 19/24. Predisposing factors for fetal vascular insult were identified in eight cases: these included maternal alcohol addiction, diabetes mellitus, congenital cytomegalovirus infection and pathological placenta with thrombotic vasculopathy and infarctions.

CONCLUSION

UCH is defined as a focal lesion of the cerebellum that may be secondary to hemorrhage and/or ischemic insult, suggesting a clastic origin, particularly when imaging follow-up reveals changes over time. UCH may also be a clue for the prenatal diagnosis of PHACE syndrome. The amount of surface loss of cerebellar hemisphere does not correlate with poor prognosis. UCH with normal vermis is often associated with normal outcome.

Computed tomography of the lacrimal drainage system: retrospective study of 107 cases of dacryostenosis

PURPOSE

To evaluate the role of computed tomography in patients with dacryostenosis.

METHODS

One hundred seven cases of dacryostenosis (94 patients) were assessed by thorough clinical and lacrimal history and examination, and lacrimal region computerized tomography (CT). The lacrimal drainage system examination included the state and position of the puncta; Jones testing; lacrimal syringing; and, in the latter half of the study, telescopic nasal endoscopy. The patients were drawn from the hospital outpatients and private office of the operating lacrimal surgeon in this series (I.C.F.). Of the 107 cases, 79 either underwent dacryocystorhinostomy surgery or had this planned.

RESULTS

In 14 of the 107 cases (12 patients), preoperative CT led to an alteration of patient management, usually referral to an otolaryngologist for further evaluation or treatment. In addition to the detection of two tumors extrinsic to the sac, conditions such as ethmoiditis, lacrimal sac mucoceles, soft tissue opacity in the nasolacrimal duct, gross nasal polyposis, fungal sinusitis, and a dacryolith were observed by CT.

CONCLUSION

Similar to the role of functional endoscopic sinus surgery in otolaryngology, CT imaging will become increasingly important in the assessment of many patients with symptoms of lacrimal drainage obstruction.

PHACE syndrome: clinical manifestations, diagnostic criteria, and management

Infantile hemangioma can be linked to other organ malformations. In 1996, PHACE syndrome was first defined as the association of large and segmental infantile hemangioma, usually on the face, head, or cervical region, with malformations of the posterior fossa of the brain, arterial anomalies of the central nervous system, coarctation of the aorta, cardiac defects, and ocular abnormalities. Over 300 cases of PHACE syndrome have been reported, and it is cconsidered one of the most common neurocutaneous vascular disorders in childhood. Knowledge of the features and locations of lesions that imply a greater risk of systemic involvement is crucial for the diagnosis and proper management of PHACE syndrome patients. This review highlights the diagnostic criteria for PHACE syndrome, the imaging workup for extracutaneous involvement, the treatment of infantile hemangioma, and the importance of a multidisciplinary approach in the management of these patients.

Diagnostic imaging of cystic lesions in the child's orbit

The child's orbit may be involved with a variety of cysts and cyst-like lesions. Such lesions may represent development anomalies of the globe and orbit, acquired lesions of the orbit, or cystic expansions from contiguous structures. CT and MR imaging are important diagnostic tools that aid the ophthalmologist in establishing the correct diagnosis and defining the extent of these cystic lesions.

Morning glory syndrome: clinical, computerized tomographic, and ultrasonographic findings

OBJECTIVE

To evaluate the ophthalmic, radiologic, and ultrasonographic findings in morning glory syndrome.

PATIENTS AND METHODS

Retrospective review of patients' charts.

RESULTS

Twenty-one patients were included. Visual acuity was 20/200 or better in 50% of the eyes. Three eyes developed a retinal detachment. When computerized tomography of the orbit demonstrated peripapillary scleral staphyloma and intraocular calcifications, this correlated with poor visual acuity. Computerized tomography of the brain revealed abnormalities in three asymptomatic patients. B-scan ultrasonography demonstrated retinal tissue overhanging the peripapillary scleral staphyloma.

CONCLUSIONS

Morning glory syndrome has a spectrum of severity, with most patients retaining useful vision. Orbital and cerebral computerized tomography scan as well as B-scan ultrasonography may help with diagnosis and management.

Growth of the fetal lens and orbit

OBJECTIVES

To present normal lens and orbital measurement ranges by gestational age.

METHODS

Three hundred and thirty-five women with uneventful pregnancies were evaluated from the 15th to the 40th week of gestation. Lens and orbital measurements were added to routine biometric measurements for normal fetuses.

RESULTS

A strong linear correlation was observed between gestational age (GA) and lens diameter (R(2)=0.89; P<0.0001), circumference (R(2)=0.89; P<0.0001), and surface (R(2)=0.90; P<0.0001). A linear correlation was also found between GA and orbital diameter (R(2)=0.92; P<0.0001), circumference (R(2)=0.92; P<0.0001) and surface (R(2)=0.95; P<0.0001). A linear growth function was observed between biparietal diameter and both lens diameter (R(2)=0.90; P<0.0001) and orbital diameter (R(2)=0.94; P<0.0001).

CONCLUSION

Lens and orbital measurements provide normative data for fetal growth and development. These data may be also helpful in detecting fetal ocular anomalies.

Mutations in KIAA0753 cause Joubert syndrome associated with growth hormone deficiency

Joubert syndrome and related disorders (JSRD) are a heterogeneous group of ciliopathies defined based on the mid-hindbrain abnormalities that result in the characteristic "molar tooth sign" on brain imaging. The core clinical findings of JSRD are hypotonia, developmental delay, abnormal eye movements and breathing abnormalities. To date, more than 30 JSRD genes that encode proteins important for structure and/or function of cilia have been identified. Here, we present 2 siblings with Joubert syndrome associated with growth hormone deficiency. Whole exome sequencing of the family identified compound heterozygous mutations in KIAA0753, i.e., a missense mutation (p.Arg257Gly) and an intronic mutation (c.2359-1G>C). The intronic mutation alters normal splicing by activating a cryptic acceptor splice site in exon 16. The novel acceptor site skips nine nucleotides, deleting three amino acids from the protein coding frame. KIAA0753 (OFIP) is a centrosome and pericentriolar satellite protein, previously not known to cause Joubert syndrome. We present comprehensive clinical descriptions of the Joubert syndrome patients as well as the cellular phenotype of defective ciliogenesis in the patients' fibroblasts.

CT and MR imaging of the pediatric orbit

Orbital abnormalities encountered in the pediatric population differ substantially from those found in adult patients. Retinoblastoma, the most serious intraocular tumor, is often difficult to diagnose, but use of computed tomography (CT) (which reveals the characteristic focal calcification) and magnetic resonance (MR) imaging allows this tumor to be differentiated from pseudogliomas, such as Coats disease, and retrolental fibroplasia. CT and MR imaging help in the differentiation of orbital cellulitis from preseptal, lacrimal, and eyelid infectious processes and of orbital pseudotumor from Graves disease. In cases of orbital trauma, CT is excellent for detecting orbital fractures and metallic foreign bodies; MR imaging is better for depicting ocular and optic nerve injuries. Both modalities allow the differentiation of rhabdomyosarcoma from dermoid, cavernous hemangioma, and lymphangioma and provide helpful information for the diagnosis of many other tumors. Since CT and MR imaging have widely expanded the capabilities of orbital imaging, it is more important than ever before for radiologists to understand pediatric orbital disease.

Early sonographic detection of recurrent fetal eye anomalies

OBJECTIVE

To determine the possible association between congenital eye anomaly of a previous child in the family and current congenital eye anomaly.

METHODS

An early transvaginal anomaly scan at 14-16 gestational weeks was used to diagnose fetal eye anomalies in five cases in which at least one previous child in the family had the same congenital eye anomaly.

RESULTS

At least one cataract was detected in four of the five fetuses and bilateral anophthalmia in one. The congenital cataract in one case was part of multiple pterygium syndrome. Both of these extremely rare malformations are commonly associated with other fetal anomalies.

CONCLUSION

Our data suggest that a detailed targeted ultrasound survey with a special focus on the orbital region should be offered at the time of genetic counseling to couples with children with congenital eye anomalies.

Biallelic Mutations in TMTC3, Encoding a Transmembrane and TPR-Containing Protein, Lead to Cobblestone Lissencephaly

Cobblestone lissencephaly (COB) is a severe brain malformation in which overmigration of neurons and glial cells into the arachnoid space results in the formation of cortical dysplasia. COB occurs in a wide range of genetic disorders known as dystroglycanopathies, which are congenital muscular dystrophies associated with brain and eye anomalies and range from Walker-Warburg syndrome to Fukuyama congenital muscular dystrophy. Each of these conditions has been associated with alpha-dystroglycan defects or with mutations in genes encoding basement membrane components, which are known to interact with alpha-dystroglycan. Our screening of a cohort of 25 families with recessive forms of COB identified six families affected by biallelic mutations in TMTC3 (encoding transmembrane and tetratricopeptide repeat containing 3), a gene without obvious functional connections to alpha-dystroglycan. Most affected individuals showed brainstem and cerebellum hypoplasia, as well as ventriculomegaly. However, the minority of the affected individuals had eye defects or elevated muscle creatine phosphokinase, separating the TMTC3 COB phenotype from typical congenital muscular dystrophies. Our data suggest that loss of TMTC3 causes COB with minimal eye or muscle involvement.

Bilateral congenital corneal keloids and anterior segment mesenchymal dysgenesis in a case of Rubinstein-Taybi syndrome

PURPOSE

To report the unusual association of bilateral corneal keloids and anterior segment mesenchymal dysgenesis in a child with Rubinstein-Taybi syndrome.

METHODS

Case report of a 2-year-old boy.

RESULTS

Excision of the epicorneal mass in the right eye was followed by recurrence of the lesion. Multiple penetrating keratoplasties were unsuccessful in reconstructing the anterior segment because of recurrent corneal epithelial breakdown, suggesting limbal stem cell insufficiency. Histopathology and electron microscopy of the excised mass lesion showed features typical of a corneal keloid: thickened keratinized epithelium, absent Bowman's layer, and fibrovascular hyperplasia, with haphazard orientation of the collagen lamellae. Ultrasound biomicroscopy and intraoperative findings suggested a diagnosis of Peter anomaly, but genetic analysis did not show a PAX6 mutation.

CONCLUSION

The findings in our patient add to the spectrum of ocular changes described in Rubinstein-Taybi syndrome and confirm earlier reports of poor ocular prognosis in corneal keloids and Rubinstein-Taybi syndrome.

Diagnostic echographic findings in cryptophthalmos syndrome (Fraser syndrome)

We report two male siblings with cryptophthalmos syndrome (Fraser syndrome), an autosomal recessive multiple malformation syndrome with cryptophthalmos, abnormal genitalia, and syndactyly of the fingers and toes as major clinical symptoms. Renal anomalies (uni- or bilateral agenesis) occur in 85 per cent. In the second trimester of both pregnancies (at 23.5 and 18.5 weeks, respectively), echographic examination revealed multiple anomalies: oligoamnios sequence and fetal hydrops with nuchal oedema. Contrasting with the oligohydramnios, the lungs were voluminous and hyperechogenic. Fetopathological examination revealed that the oligoamnios sequence was due to major renal abnormalities (bilateral renal agenesis in the first, and unilateral renal agenesis and contralateral multicystic renal dysplasia in the second sibling). Laryngeal substenosis had resulted in another malformation sequence consisting of overdistended lungs, and non-immune fetal hydrops. The present experience shows that in the presence of an oligoamnios sequence with contrastingly voluminous, hyperechogenic lungs, the diagnosis of cryptophthalmos syndrome should seriously be considered in the differential diagnosis.

Congenital cystic eye with multiple ocular and intracranial anomalies

We describe a newborn with congenital cystic eye, contralateral persistent hyperplastic primary vitreous, and cerebrocutaneous abnormalities. The cerebrocutaneous abnormalities consisted of agenesis of the corpus callosum, midbrain deformity, malformed sphenoid bone, right upper eyelid coloboma, and a left periocular hamartoma. The results of karyotype analysis of the patient and his parents were normal. The association of congenital cystic eye with contralateral persistent hyperplastic primary vitreous has not been previously reported, to our knowledge. Although no unifying diagnosis exists for the collection of anomalies demonstrated in this patient, the term cranial ectodermopathy broadly classifies most of the defects.

A rare case of arhinia with severe airway obstruction: case report and review of the literature

A rare case of a newborn suffering from arhinia with complete airway obstruction is reported. The complexity of the life-threatening airway obstruction is described and adequate treatment is reported. The relevant literature is reviewed, and the different approaches to treatment are discussed.

Laryngeal atresia presenting as fetal ascites, olygohydramnios and lung appearance mimicking cystic adenomatoid malformation in a 25-week-old fetus with Fraser syndrome

We describe a 25-week-old female fetus of consanguineous parents with ultrasonographic findings of increased echogenicity of lungs mimicking CAM (cystic adenomatoid malformation) type III, olygohydramnios and fetal ascites. A therapeutic abortion was performed and unilateral cryptophthalmos, laryngeal atresia and bilateral syndactyly of the hands and feet were observed at post-mortem. These findings confirmed the diagnosis of Fraser syndrome after abortion.

SLC38A8 mutations result in arrested retinal development with loss of cone photoreceptor specialization

Foveal hypoplasia, optic nerve decussation defects and anterior segment dysgenesis is an autosomal recessive disorder arising from SLC38A8 mutations. SLC38A8 is a putative glutamine transporter with strong expression within the photoreceptor layer in the retina. Previous studies have been limited due to lack of quantitative data on retinal development and nystagmus characteristics. In this multi-centre study, a custom-targeted next generation sequencing (NGS) gene panel was used to identify SLC38A8 mutations from a cohort of 511 nystagmus patients. We report 16 novel SLC38A8 mutations. The sixth transmembrane domain is most frequently disrupted by missense SLC38A8 mutations. Ninety percent of our cases were initially misdiagnosed as PAX6-related phenotype or ocular albinism prior to NGS. We characterized the retinal development in vivo in patients with SLC38A8 mutations using high-resolution optical coherence tomography. All patients had severe grades of arrested retinal development with lack of a foveal pit and no cone photoreceptor outer segment lengthening. Loss of foveal specialization features such as outer segment lengthening implies reduced foveal cone density, which contributes to reduced visual acuity. Unlike other disorders (such as albinism or PAX6 mutations) which exhibit a spectrum of foveal hypoplasia, SLC38A8 mutations have arrest of retinal development at an earlier stage resulting in a more under-developed retina and severe phenotype.

Prenatal abnormal features of the fourth ventricle in Joubert syndrome and related disorders

Joubert syndrome and related disorders (JSRD) are characterized by absence or underdevelopment of the cerebellar vermis and a malformed brainstem. This family of disorders is a member of an emerging class of diseases called ciliopathies. We describe the abnormal features of the brain, particularly the fourth ventricle, in seven fetuses affected by JSRD. In three cases abnormality of the fourth ventricle was isolated and in four cases there were associated malformations. The molar tooth sign (MTS) was always present and visible on two-dimensional ultrasound and, when performed, on three-dimensional ultrasound and magnetic resonance imaging. The fourth ventricle was always abnormal, in both axial and sagittal views, presenting pathognomonic deformities. It is important to identify JSRD, preferably prenatally or at least postnatally, due to its high risk of recurrence of about 25%. A detailed prenatal assessment of the fourth ventricle in several views may help to achieve this goal.

Walker-Warburg syndrome: prenatal ultrasound findings

The prenatal sonographic findings in a case of Walker-Warburg syndrome are described. The patient was not at risk for this condition. Ultrasound examination at 34 weeks' gestation revealed hydrocephaly, Dandy-Walker anomaly, and striking ocular abnormalities. From a review of the literature it appears that while intracranial abnormalities can lead to the diagnosis in cases at risk for this syndrome, ocular abnormalities are rather characteristic for this syndrome and they should be searched for in every case of hydrocephaly or encephalocele.

Sonographic 'molar tooth' sign in the diagnosis of Joubert syndrome

The characteristic imaging finding common to Joubert syndrome and related disorders is the 'molar tooth' sign. The prenatal diagnosis of Joubert syndrome using both ultrasound and fetal magnetic resonance imaging (MRI) in families with an affected child has been reported previously. We report two cases in which the molar tooth sign was identified by sonography at 26 + 4 weeks and at 20 + 6 weeks, respectively, prior to fetal MRI or genetic testing. In both cases the finding was subsequently confirmed on fetal MRI. As definitive prenatal genetic testing may not be conclusive in Joubert syndrome, the ability to identify the molar tooth sign sonographically before 24 weeks provides a valuable adjunct to prenatal diagnosis.

High-frequency ultrasonography findings in persistent hyperplastic primary vitreous

PURPOSE

To identify anatomic correlates in eyes with persistent hyperplastic primary vitreous (PHPV) by using high-frequency ultrasonography.

METHOD

Three main groups of patients were studied by means of high-frequency ultrasonography over a 19-month period. Group I included 9 eyes of 9 patients with newly diagnosed unilateral PHPV. Group II included 4 eyes of 4 patients with unilateral PHPV that had been previously surgically treated. Group III included 22 eyes and was a control group of patients without PHPV. This group consisted of the 5 contralateral normal eyes of 5 patients with unilateral PHPV in the fellow eye, both eyes of one patient with uncomplicated unilateral cataracts, the affected eye of one patient with unilateral uncomplicated cataract, the affected eye of one patient with isolated retinal coloboma, and 13 normal eyes of 7 young adults. Group I and II patients also had B-scan ultrasonography performed and had any intraoperative findings noted.

RESULTS

Characteristic features of PHPV, such as centrally dragged ciliary processes and swollen anteriorly displaced lens, were observed only in those eyes with PHPV. A new echographic finding of a double linear echo was observed in the region of the pars plana or plicata only in eyes with PHPV. This finding was confirmed intraoperatively to be consistent with a thickened adherent anterior hyaloid face and not to be an anteriorly inserted peripheral retina.

CONCLUSION

High-frequency ultrasound can be reliably used to distinguish characteristic features of PHPV. To our knowledge this is the first such description of the use of high-frequency ultrasonography in PHPV eyes. Furthermore, the presence of a thickened adherent anterior hyaloid face may help explain the well-recognized complications of peripheral retinal tears and retinal detachments during and after surgical intervention.

Aicardi syndrome: early neuroradiological manifestations and results of DNA studies in one patient

A patient with Aicardi syndrome is presented. We report results of DNA analysis from the patient and her parents with probes mapped to Xp21.3-22.3 in an attempt to localize a deletion in this region. No signs of a microdeletion could be detected, using 5 different DNA markers. Further, it is suggested that a specific combination of cerebral abnormalities may be characteristic of the syndrome and that antenatal ultrasonographic diagnosis may be feasible.