Alagille Syndrome: Clinical and Ocular Pathognomonic Features

Macular atrophy and focal choroidal excavation in a patient with JAG1- related alagille syndrome

INTRODUCTION

Alagille syndrome (AGS) is a genetic disease with multisystemic affection, including ocular manifestations. Recently, a high frequency of posterior segment findings, including macular changes, has been reported. This publication aims to report an unusual finding of macular atrophy and a focal choroidal excavation in a patient with JAG1 related AGS.

METHODS

Case report.

RESULTS

This publication describes an atypical presentation of focal choroidal excavation (FCE) and unilateral macular atrophy in a 7-year-old male with Alagille syndrome (AGS). Genetic analysis revealed a pathogenic variant in the JAG1 gene. Ophthalmological examination and imaging findings demonstrated characteristic ocular manifestations of AGS, including posterior embryotoxon, chorioretinal atrophy, and thinning of the choroid.

CONCLUSION

The presence of FCE in AGS is uncommon, and the underlying mechanisms remain unclear. Further exploration of similar cases is necessary to better understand the evolution and visual prognosis in patients with AGS and FCE.

Sex differences and risk factors for bleeding in Alagille syndrome

Spontaneous bleeds are a leading cause of death in the pediatric JAG1-related liver disease Alagille syndrome (ALGS). We asked whether there are sex differences in bleeding events in patients, whether Jag1^Ndr/Ndr mice display bleeds or vascular defects, and whether discovered vascular pathology can be confirmed in patients non-invasively. We performed a systematic review of patients with ALGS and vascular events following PRISMA guidelines, in the context of patient sex, and found significantly more girls than boys reported with spontaneous intracranial hemorrhage. We investigated vascular development, homeostasis, and bleeding in Jag1^Ndr/Ndr mice, using retina as a model. Jag1^Ndr/Ndr mice displayed sporadic brain bleeds, a thin skull, tortuous blood vessels, sparse arterial smooth muscle cell coverage in multiple organs, which could be aggravated by hypertension, and sex-specific venous defects. Importantly, we demonstrated that retinographs from patients display similar characteristics with significantly increased vascular tortuosity. In conclusion, there are clinically important sex differences in vascular disease in ALGS, and retinography allows non-invasive vascular analysis in patients. Finally, Jag1^Ndr/Ndr mice represent a new model for vascular compromise in ALGS.

Posterior Embryotoxon Revisited: An Immunohistologic Study

PURPOSE

This series describes the immunopathologic features of posterior embryotoxon (PE) and demonstrates that it is not an anterior displaced Schwalbe's line as commonly described, but a peripheral corneal stromal nub variable in location with abnormal extracellular matrix.

DESIGN

Case series.

PARTICIPANTS

Archived specimens from patients with PE.

METHODS

Sections from archived formalin-fixed, paraffin-embedded specimens (n = 9; 7 autopsy and 2 trabeculectomy specimens) were examined by light microscopy. Immunohistochemistry was performed on 5 specimens to characterize the extracellular matrix composition of PE.

RESULTS

Posterior embryotoxon appeared as nubs of whorled collagen extending from the corneal stroma, lined in some instances, by Descemet membrane. These nubs were located anterior to Schwalbe's line (n = 4), posteriorly (n = 1), partially embedded in the trabecular meshwork (n = 1), or at Schwalbe's line (n = 2). Qualitatively, collagen I labeling of the PE stroma was similar or weaker than the corneal stroma, whereas collagen III staining was focal and slightly more intense compared with the corneal stroma. Lumican and keratan sulfate staining was similar or less intense in PE compared with the corneal stroma.

MAIN OUTCOME MEASURES

Identify location of PE and its immunohistochemical features.

CONCLUSIONS

In contrast to the widely accepted definition of PE as a prominent, anteriorly displaced Schwalbe line, histologic evidence suggests that it is a direct extension of the corneal stroma with variable locations that may displace the attenuated Descemet membrane when located anterior to or at Schwalbe's line. Immunohistochemical examination revealed that the composition of PE's extracellular matrix was similar to corneal stroma but with some variability in staining intensity.

Broadening the clinical spectrum of ALGS: an Egyptian cohort with five novel mutations in JAG1 gene

Background

Alagille syndrome (ALGS) is a rare autosomal dominant multisystem disorder that affects the liver, heart, eyes, vertebrae, and kidneys and is associated with characteristic facies. This work aimed to study the spectrum of the clinical features of ALGS in an Egyptian cohort of patients in conjunction with partial sequencing of the JAG1 gene.

Methods

This study included 17 pediatric ALGS patients diagnosed on clinical grounds: facial features, cholestatic liver disease, and cardiac, vertebral, and ocular findings. Molecular analysis was conducted in 10 selected exons of the JAG1 gene.

Results

The clinical features of ALGS included cholestatic liver disease (100%), facial dysmorphism (100%), cardiac abnormalities (88.2%), butterfly vertebrae (64.7%), posterior embryotoxon (35.2%), poor growth (41%), xanthomata (11.8%), and hiatus hernia (11.8%). Five novel pathogenic JAG1 mutations were identified in this study, including two nonsense mutations, one splicing mutation, one frameshift insertion, and one frameshift deletion. In two patients, the mutations were confirmed to be de novo, as the mutations could not be detected in both parents.

Conclusion

Five novel JAG1 pathogenic variants were identified in this study. This is the first molecular study to report pathogenic mutations in the JAG1 gene within an Egyptian cohort of children with ALGS.

Characterization of the Spectrum of Ophthalmic Changes in Patients With Alagille Syndrome

Purpose

The purpose of this study was to characterize the phenotypic spectrum of ophthalmic findings in patients with Alagille syndrome.

Methods

We conducted a retrospective, observational, multicenter, study on 46 eyes of 23 subjects with Alagille syndrome. We reviewed systemic and ophthalmologic data extracted from medical records, color fundus photography, fundus autofluorescence, optical coherence tomography, visual fields, electrophysiological assessments, and molecular genetic findings.

Results

Cardiovascular abnormalities were found in 83% of all cases (of those, 74% had cardiac murmur), whereas 61% had a positive history of hepatobiliary issues, and musculoskeletal anomalies were present in 61% of all patients. Dysmorphic facies were present in 16 patients, with a broad forehead being the most frequent feature. Ocular symptoms were found in 91%, with peripheral vision loss being the most frequent complaint. Median (range) Snellen visual acuity of all eyes was 20/25 (20/20 to hand motion [HM]). Anterior segment abnormalities were present in 74% of the patients; of those, posterior embryotoxon was the most frequent finding. Abnormalities of the optic disc were found in 52%, and peripheral retinal abnormalities were the most frequent ocular finding in this series, found in 96% of all patients. Fifteen JAG1 mutations were identified in 16 individuals; of those, 6 were novel.

Conclusions

This study reports a cohort of patients with Alagille syndrome in which peripheral chorioretinal changes were more frequent than posterior embryotoxon, the most frequent ocular finding according to a number of previous studies. We propose that these peripheral chorioretinal changes are a new hallmark to help diagnose this syndrome.

Case Report: Alagille Syndrome Presenting with Angioid Streaks

SIGNIFICANCE

Alagille syndrome is rare genetic disease, which affects liver and heart function. Cases are frequently diagnosed late, and a complete ocular examination aids in the diagnosis. Although ophthalmic manifestations are usually benign, occasionally, sight-threatening complications occur.

PURPOSE

The case presented herein highlights a rare condition, which usually can be diagnosed by the ophthalmological findings. However, in this particular case report, the complication of angioid streaks and choroidal neovascularization is reported for the first time in Alagille syndrome.

CASE REPORT

Α 32-year-old woman diagnosed with Alagille syndrome presented with diminution of vision in the left eye. The cause was choroidal neovascularization related to angioid streaks. She was treated with intravitreal injections of ranibizumab but developed an extensive macular scar. A few years later, she developed the same complication in the right eye and was treated similarly.

CONCLUSIONS

Alagille syndrome has many ophthalmic manifestations, most of them benign with minimal threat to vision. Herein for the first time, we present a case of Alagille syndrome with angioid streak-related choroidal neovascularization, which resulted in severe vision loss.

Intracranial Hypertension and Papilledema in a Large Cohort of Pediatric Patients With Alagille Syndrome

AIMS AND BACKGROUND

Ophthalmic abnormalities are amongst the 5 major criteria required for a diagnosis of Alagille syndrome (ALGS), of which embryotoxon, pseudopapilledema, and hypopigmented retinopathy are the most common. Papilledema with or without intracranial hypertension (ICHT) is rarely described. We report 9 pediatric cases of ALGS with bilateral papilledema, 5 of which were diagnosed with ICHT.

METHODS

The ophthalmic data from 85 patients with clinically and/or genetically (n = 37) proven ALGS were reviewed. The study inclusion criteria were a positive diagnosis of ALGS and availability of ophthalmic follow-up data. Ophthalmic data from 40 patients after liver transplantation (LT) for other indications were also analyzed.

RESULTS

Nine (13.0%) of the 69 patients meeting the inclusion criteria had papilledema. The neurological and neuroimaging results in all 9 patients were normal. These 9 patients were categorized into 4 groups: a nontransplant group (n = 1), a group with pretransplant papilledema persistent after LT (n = 2), a group with papilledema occurring after LT with spontaneous resolution (n = 1), and a group with papilledema and signs of ICHT after LT (n = 5). The patients with ICHT were treated with steroids alone (n = 1) or with acetazolamide (n = 4). A ventriculoperitoneal shunt was placed in 2 of the 5 cases because of progressive visual loss. Pseudopapilledema was present in 10 additional patients (14.5%, 10/69). One (2.5%) of the 40 patients without ALGS developed papilledema after LT.

CONCLUSIONS

True ICHT may be underdiagnosed in patients with ALGS. Our findings underscore the need for close ophthalmic follow-up before and after LT in these patients.

Genetic Syndromes Associated with Congenital Cardiac Defects and Ophthalmologic Changes - Systematization for Diagnosis in the Clinical Practice

BACKGROUND

Numerous genetic syndromes associated with heart disease and ocular manifestations have been described. However, a compilation and a summarization of these syndromes for better consultation and comparison have not been performed yet.

OBJECTIVE

The objective of this work is to systematize available evidence in the literature on different syndromes that may cause congenital heart diseases associated with ocular changes, focusing on the types of anatomical and functional changes.

METHOD

A systematic search was performed on Medline electronic databases (PubMed, Embase, Cochrane, Lilacs) of articles published until January 2016. Eligibility criteria were case reports or review articles that evaluated the association of ophthalmic and cardiac abnormalities in genetic syndrome patients younger than 18 years.

RESULTS

The most frequent genetic syndromes were: Down Syndrome, Velo-cardio-facial / DiGeorge Syndrome, Charge Syndrome and Noonan Syndrome. The most associated cardiac malformations with ocular findings were interatrial communication (77.4%), interventricular communication (51.6%), patent ductus arteriosus (35.4%), pulmonary artery stenosis (25.8%) and tetralogy of Fallot (22.5%).

CONCLUSION

Due to their clinical variability, congenital cardiac malformations may progress asymptomatically to heart defects associated with high morbidity and mortality. For this reason, the identification of extra-cardiac characteristics that may somehow contribute to the diagnosis of the disease or reveal its severity is of great relevance.

Congenital optic nerve anomalies

OBJECTIVE

To update the current knowledge about congenital optic disc anomalies.

METHODS

A comprehensive literature search was performed in the major biomedical databases.

RESULTS

Patients with these anomalies usually have poor vision in infancy. Refractive errors are common, and serous retinal detachment may develop in some of these anomalies. It is critically important to clinically differentiate between these congenital optic disc anomalies, as central nervous system malformations are common in some, whereas others may be associated with systemic anomalies.

CONCLUSIONS

Congenital optic disc anomalies are a heterogeneous group of pathologies with characteristic fundus appearance and systemic associations. We should always try to make a correct diagnosis, in order to ask for specific tests, as well as to provide an adequate follow-up.

Optic disk drusen in children

Optic disk drusen occur in 0.4% of children and consist of acellular intracellular and extracellular deposits that often become calcified over time. They are typically buried early in life and generally become superficial, and therefore visible, later in childhood, at the average age of 12 years. Their main clinical significance lies in the ability of optic disk drusen, particularly when buried, to simulate true optic disk edema. Misdiagnosing drusen as true disk edema may lead to an invasive and unnecessary workup for elevated intracranial pressure. Ancillary testing, including ultrasonography, fluorescein angiography, fundus autofluorescence, and optical coherence tomography, may aid in the correct diagnosis of optic disk drusen. Complications of optic disk drusen in children include visual field defects, hemorrhages, choroidal neovascular membrane, nonarteritic anterior ischemic optic neuropathy, and retinal vascular occlusions. Treatment options for these complications include ocular hypotensive agents for visual field defects and intravitreal anti-vascular endothelial growth factor agents for choroidal neovascular membranes. In most cases, however, children with optic disk drusen can be managed by observation with serial examinations and visual field testing once true optic disk edema has been excluded.

Anterior Chamber Pathology in Alagille Syndrome

BACKGROUND

Alagille syndrome is an autosomal dominant disorder characterized by neonatal cholestasis, characteristic facies, and cardiac abnormalities. Ocular abnormalities include posterior embryotoxon, mosaic pattern of iris stromal hypoplasia, microcornea, optic disc drusen, and pigmentary retinopathy. We present the second report of ocular pathology in two cases of Alagille syndrome.

METHODS

Gross and histologic preparations of four eyes of two patients.

RESULTS

Posterior embryotoxon is seen in both cases, with iris processes extending to the embryotoxon in case 1. Case 1 exhibited distinctly abnormal iris stroma with a prominent cleft separating the anterior and posterior stroma. Lacy vacuolization of the iris pigment epithelium was seen in case 2.

CONCLUSIONS

Alagille syndrome is primarily a hepatic disorder but presents with several distinct ocular pathologic features, most specifically posterior embryotoxon. This and the unusual iris stroma may be caused by improper migration of neural crest cells due to mutation in the Jagged 1 gene that causes Alagille syndrome. Patients with Alagille syndrome rarely present to ocular autopsy. Pathology findings may help us better understand the pathophysiology of the ocular abnormalities in this disorder.

The frequency of occurrence of certain corneal conditions by age and sex in Iranian adults

PURPOSE

To determine the prevalence of posterior embryotoxon, corneal opacity, pigment on endothelium, corneal dystrophy, and corneal vascularization in a middle-aged Iranian population, and their association with age and sex.

METHODS

In a cross-sectional study with multistage cluster sampling, subjects were chosen from 40 to 64-year-old residents of Shahroud in northern Iran. Participants had ophthalmic examinations before and after pupil dilation. Corneal abnormalities were diagnosed by an ophthalmologist using a slit lamp.

RESULTS

Of the 6311 invitees, 5190 people (82.2%) participated; 58.6% (n=3040) were female. The prevalence of posterior embryotoxon, corneal opacity, and pigment on endothelium were 14.7% (95% CI: 13.4-16.0), 4.1% (95% CI: 3.4-4.7) and 1.2% (95% CI: 0.9-1.5), respectively, and corneal dystrophy and corneal vascularization were seen in 0.3% (95% CI: 0.2-0.5) and 3.7% (95% CI: 3.0-4.3), respectively. Unlike posterior embryotoxon, the prevalence of all studied abnormalities increased with age after adjusting for sex. The prevalence of posterior embryotoxon (p=0.023) and corneal dystrophy (p=0.038) was significantly higher in women, and the prevalence of corneal opacity (p<0.001) was significantly higher in men. After adjusting for age, sex, and cataract, cases with corneal opacity and corneal vascularization demonstrated significantly worse uncorrected and corrected visual acuity (p<0.001).

CONCLUSION

This report is the first to explore the prevalence of a variety of corneal conditions in a Middle-Eastern population. The findings indicate that one out of five people may have some sort of corneal conditions, and some can impact corrected visual acuity.

Multimodal imaging of optic disc drusen

PURPOSE

To evaluate optic disc drusen, extracellular protein deposits known to contain numerous aggregates of mitochondria, using multimodal modalities featuring optical coherence tomography (OCT) and autofluorescence imaging.

DESIGN

Retrospective observational case series.

METHODS

Eyes with optic nerve drusen were examined with enhanced depth imaging (EDI)-OCT, swept source OCT, and fundus autofluorescence using a fundus camera.

RESULTS

Twenty-six eyes of 15 patients with optic disc drusen were evaluated. EDI-OCT and swept source OCT showed multiple optic disc drusen at different levels; most were located immediately anterior to the lamina cribrosa. The drusen were ovoid regions of lower reflectivity that were bordered by hyperreflective material, and in 12 eyes (46.2%) there were internal hyperreflective foci. The mean diameter of the optic disc drusen as measured in OCT images was 686.8 (standard deviation ± 395.2) μm. There was a significant negative correlation between the diameter of the optic disc drusen and the global retinal nerve fiber layer thickness (r = -0.61, P = .001). There was a significant negative correlation between proportion of the optic disc drusen area occupied by optic nerve drusen as detected by autofluorescence imaging and the global retinal nerve fiber layer thickness (r = -0.63, P = .001).

CONCLUSIONS

Deeper-penetration OCT imaging demonstrated the internal characteristics of optic disc drusen and their relationship with the lamina cribrosa in vivo. This study also showed that both the larger the drusen and the more area of the optic canal occupied by drusen, the greater the associated retinal nerve fiber layer abnormalities.