Ocular and orbital manifestations of the inherited bone marrow failure syndromes: Fanconi anemia and dyskeratosis congenita

A naturally occurring canine model of syndromic congenital microphthalmia

In humans, the prevalence of congenital microphthalmia is estimated to be 0.2-3.0 for every 10,000 individuals, with nonocular involvement reported in ∼80% of cases. Inherited eye diseases have been widely and descriptively characterized in dogs, and canine models of ocular diseases have played an essential role in unraveling the pathophysiology and development of new therapies. A naturally occurring canine model of a syndromic disorder characterized by microphthalmia was discovered in the Portuguese water dog. As nonocular findings included tooth enamel malformations, stunted growth, anemia, and thrombocytopenia, we hence termed this disorder Canine Congenital Microphthalmos with Hematopoietic Defects. Genome-wide association study and homozygosity mapping detected a 2 Mb candidate region on canine chromosome 4. Whole-genome sequencing and mapping against the Canfam4 reference revealed a Short interspersed element insertion in exon 2 of the DNAJC1 gene (g.74,274,883ins[T70]TGCTGCTTGGATT). Subsequent real-time PCR-based mass genotyping of a larger Portuguese water dog population found that the homozygous mutant genotype was perfectly associated with the Canine Congenital Microphthalmos with Hematopoietic Defects phenotype. Biallelic variants in DNAJC21 are mostly found to be associated with bone marrow failure syndrome type 3, with a phenotype that has a certain degree of overlap with Fanconi anemia, dyskeratosis congenita, Shwachman-Diamond syndrome, Diamond-Blackfan anemia, and reports of individuals showing thrombocytopenia, microdontia, and microphthalmia. We, therefore, propose Canine Congenital Microphthalmos with Hematopoietic Defects as a naturally occurring model for DNAJC21-associated syndromes.

Implementation of a prospective screening strategy to identify adults with a telomere biology disorder among those undergoing lung transplant evaluation for interstitial lung disease

INTRODUCTION

Patients with interstitial lung disease (ILD) secondary to telomere biology disorders (TBD) experience increased morbidity after lung transplantation. Identifying patients with TBD may allow for personalized management to facilitate better outcomes. However, establishing a TBD diagnosis in adults is challenging.

METHODS

A TBD screening questionnaire was introduced prospectively into the lung transplant evaluation. Patients with ILD screening positive were referred for comprehensive TBD phenotyping and concurrent telomere length measurement and germline genetic testing.

RESULTS

Of 98 patients, 32 (33%) screened positive. Eight patients (8% of total; 25% of patients with a positive screen) met strict TBD diagnostic criteria, requiring either critically short lymphocyte telomeres (<1st percentile) (n = 4), a pathogenic variant in a TBD-associated gene (n = 1), or both (n = 3) along with a TBD clinical phenotype. Additional patients not meeting strict diagnostic criteria had histories consistent with TBD along with telomere lengths <10th percentile and/or rare variants in TBD-associated genes, highlighting a critical need to refine TBD diagnostic criteria for this patient population.

CONCLUSION

A TBD phenotype screening questionnaire in patients with ILD undergoing lung transplant evaluation has a diagnostic yield of 25%. Additional gene discovery, rare variant functional testing, and refined TBD diagnostic criteria are needed to realize the maximum benefit of testing for TBD in patients undergoing lung transplantation.

Retinal vasoproliferative tumour: differential diagnoses and treatment considerations in a paediatric patient

An early adolescent man was referred to the ocular oncology service for evaluation of a pale, raised fundus lesion in the inferotemporal quadrant of his right eye. Unaided visual acuities were 20/20 OD and 20/20 OS. He had no medical, ocular or family history of note. Retinal vasoproliferative tumour with progressive retinal exudation was the working diagnosis. Improvement in tumour features and exudation regression were noted following a combination of argon laser therapy, cryotherapy and intravitreal steroid injection. Paediatric intraocular tumours present a complex list of differential diagnoses and offer significant diagnostic and management challenges. Discussed here are the differential diagnoses and treatment considerations in the setting of an intraocular tumour in childhood.

Glaucoma and Systemic Disease

Glaucoma is the leading cause of irreversible blindness in the world. Due to its potential to cause permanent vision loss, it is important to understand how systemic conditions and their respective treatments can be associated with or increase the risk for developing glaucoma. In this review, we examined the literature for up-to-date discussions and provided commentary on glaucoma, its pathophysiology, and associated risk factors. We discuss systemic diseases and the impact, risk, and mechanism for developing glaucoma, including pharmacologically induced glaucoma; inflammatory and auto-immune conditions; infectious, dermatologic, cardiovascular, pulmonary, renal, urologic, neurologic, psychiatric and systemic malignancies: intraocular tumors; as well as pediatric, and genetic conditions. The goal of our discussion of systemic conditions including their commonality, mechanisms, treatments, and associations with developing glaucoma is to emphasize the importance of ocular examinations and follow-up with the multidisciplinary teams involved in the care of each patient to prevent unnecessary vision-loss.

Molecular etiology of defective nuclear and mitochondrial ribosome biogenesis: Clinical phenotypes and therapy

Ribosomopathies are rare congenital disorders associated with defective ribosome biogenesis due to pathogenic variations in genes that encode proteins related to ribosome function and biogenesis. Defects in ribosome biogenesis result in a nucleolar stress response involving the TP53 tumor suppressor protein and impaired protein synthesis leading to a deregulated translational output. Despite the accepted notion that ribosomes are omnipresent and essential for all cells, most ribosomopathies show tissue-specific phenotypes affecting blood cells, hair, spleen, or skin. On the other hand, defects in mitochondrial ribosome biogenesis are associated with a range of clinical manifestations affecting more than one organ. Intriguingly, the deregulated ribosomal function is also a feature in several human malignancies with a selective upregulation or downregulation of specific ribosome components. Here, we highlight the clinical conditions associated with defective ribosome biogenesis in the nucleus and mitochondria with a description of the affected genes and the implicated pathways, along with a note on the treatment strategies currently available for these disorders.

Fanconi anemia and dyskeratosis congenita/telomere biology disorders: Two inherited bone marrow failure syndromes with genomic instability

Inherited bone marrow failure syndromes (IBMFS) are a complex and heterogeneous group of genetic diseases. To date, at least 13 IBMFS have been characterized. Their pathophysiology is associated with germline pathogenic variants in genes that affect hematopoiesis. A couple of these diseases also have genomic instability, Fanconi anemia due to DNA damage repair deficiency and dyskeratosis congenita/telomere biology disorders as a result of an alteration in telomere maintenance. Patients can have extramedullary manifestations, including cancer and functional or structural physical abnormalities. Furthermore, the phenotypic spectrum varies from cryptic features to patients with significantly evident manifestations. These diseases require a high index of suspicion and should be considered in any patient with abnormal hematopoiesis, even if extramedullary manifestations are not evident. This review describes the disrupted cellular processes that lead to the affected maintenance of the genome structure, contrasting the dysmorphological and oncological phenotypes of Fanconi anemia and dyskeratosis congenita/telomere biology disorders. Through a dysmorphological analysis, we describe the phenotypic features that allow to make the differential diagnosis and the early identification of patients, even before the onset of hematological or oncological manifestations. From the oncological perspective, we analyzed the spectrum and risks of cancers in patients and carriers.

Shwachman-Diamond Syndrome With Congenital Myogenic Ptosis: Case Report of a Rare Association?

BACKGROUND

Shwachman-Diamond syndrome (SDS) is a multisystem disorder characterized by exocrine pancreatic insufficiency and bone marrow failure. There is considerable variation in the phenotypes of SDS. We present a case of an infant presenting with SDS and left-sided ptosis.

OBSERVATION

We report a case of an infant who presented with 2 episodes of severe sepsis and cytopenia, without overt symptoms of exocrine pancreatic deficiency or skeletal abnormalities. Persistent left-sided ptosis was noted in both presentations. Genetic testing confirmed the diagnosis of SDS. The left-sided ptosis was diagnosed as congenital myogenic ptosis.

CONCLUSION

The association of ptosis and other congenital bone marrow failure syndromes is well established, but this is the first description of SDS with ptosis. This association may expand our understanding of SDS phenotypes if similar cases are reported in the future.

Disease progression and clinical outcomes in telomere biology disorders

Dyskeratosis congenita related telomere biology disorders (DC/TBDs) are characterized by very short telomeres caused by germline pathogenic variants in telomere biology genes. Clinical presentations can affect all organs, and inheritance patterns include autosomal dominant (AD), autosomal recessive (AR), X-linked (XLR), or de novo. This study examined the associations between mode of inheritance with phenotypes and long-term clinical outcomes. Two hundred thirty-one individuals with DC/TBDs (144 male, 86.6% known genotype, median age at diagnosis 19.4 years [range 0 to 71.6]), enrolled in the National Cancer Institute's Inherited Bone Marrow Failure Syndrome Study, underwent detailed clinical assessments and longitudinal follow-up (median follow-up 5.2 years [range 0 to 36.7]). Patients were grouped by inheritance pattern, considering AD-nonTINF2, AR/XLR, and TINF2 variants separately. Severe bone marrow failure (BMF), severe liver disease, and gastrointestinal telangiectasias were more prevalent in AR/XLR or TINF2 disease, whereas pulmonary fibrosis developed predominantly in adults with AD disease. After adjusting for age at DC/TBD diagnosis, we observed the highest cancer risk in AR/XLR individuals. At last follow-up, 42% of patients were deceased with a median overall survival (OS) of 52.8 years (95% confidence interval [CI] 45.5-57.6), and the hematopoietic cell or solid organ transplant-free median survival was 45.3 years (95% CI 37.4-52.1). Significantly better OS was present in AD vs AR/XLR/TINF2 disease (P < .01), while patients with AR/XLR and TINF2 disease had similar survival probabilities. This long-term study of the clinical manifestations of DC/TBDs creates a foundation for incorporating the mode of inheritance into evidence-based clinical care guidelines and risk stratification in patients with DC/TBDs. This trial was registered at www.clinicaltrials.gov as #NCT00027274.

Multisystemic Manifestations in Rare Diseases: The Experience of Dyskeratosis Congenita

Dyskeratosis congenital (DC) is the first genetic syndrome described among telomeropathies. Its classical phenotype is characterized by the mucocutaneous triad of reticulated pigmentation of skin lace, nail dystrophy and oral leukoplakia. The clinical presentation, however, is heterogeneous and serious clinical complications include bone marrow failure, hematological and solid tumors. It may also involve immunodeficiencies, dental, pulmonary and liver disorders, and other minor complication. Dyskeratosis congenita shows marked genetic heterogeneity, as at least 14 genes are responsible for the shortening of telomeres characteristic of this disease. This review discusses clinical characteristics, molecular genetics, disease evolution, available therapeutic options and differential diagnosis of dyskeratosis congenita to provide an interdisciplinary and personalized medical assessment that includes family genetic counseling.

Ocular Manifestations in Patients with Fanconi Anemia: A Single-Center Experience Including 106 Patients

OBJECTIVES

To describe the prevalence of acquired ocular manifestations in patients with Fanconi anemia (FA) and to describe and correlate the congenital ocular malformations with the genetic subtypes of the disease.

STUDY DESIGN

This is a cross-sectional observational study of 106 consecutive patients with confirmed diagnosis of FA who were followed at the Hematopoietic Stem Cell Transplantation (HSCT) Service at the Federal University of Paraná, Curitiba, Parana, Brazil. Participants underwent a complete ophthalmologic evaluation and 84 patients underwent ocular ultrasound examination. This study was conducted between November 2014 and August 2017.

RESULTS

The patients ranged in age from 6 months to 43 years of age. Microphthalmia was the most common congenital ocular abnormality (95.2%). A decrease in anthropometric measurements was observed, including palpebral fissure length (78/103 patients [76.5%]), microcornea (48/103 patients [46.6%]), and ptosis (31/103 patients [30.1%]). We identified a new ophthalmic condition in 15 patients with FA, that is, epiretinal tissue on the optic disc. The genetic subtype was identified in 78 patients (79.6%), the FA-A subtype was most prevalent (50%). The most common acquired ocular manifestation (non-graft-versus-host disease [GVHD] related) in patients who did not undergo HSCT (n = 44) was limbal neovascularization (13.6%), whereas in patients who underwent HSCT (n = 62), the GVHD-related manifestation was ocular GVHD (51.6%). The most frequent symptom of ocular GVHD was keratoconjunctivitis sicca (29%).

CONCLUSIONS

Several ocular manifestations were identified in patients with FA.

CAMT-MPL: congenital amegakaryocytic thrombocytopenia caused by MPL mutations - heterogeneity of a monogenic disorder - a comprehensive analysis of 56 patients

Congenital amegakaryocytic thrombocytopenia caused by deleterious homozygous or compound heterozygous mutations in MPL (CAMT-MPL) is a rare inherited bone marrow failure syndrome presenting as an isolated thrombocytopenia at birth progressing to pancytopenia due to exhaustion of hematopoietic progenitors. The analysis of samples and clinical data from a large cohort of 56 patients with CAMT-MPL resulted in a detailed description of the clinical picture and reliable genotype-phenotype correlations for this rare disease. We extended the spectrum of CAMT causing MPL mutations regarding number (17 novel mutations) and impact. Clinical courses showed great variability with respect to the severity of thrombocytopenia, the development of pancytopenia and the consequences from bleedings. The most severe clinical problems were (i) intracranial bleedings pre- and perinatally and the resulting long-term consequences, and (ii) the development of aplastic anemia in the later course of the disease. An important and new finding was that thrombocytopenia was not detected at birth in a quarter of the patients. The rate of non-hematological abnormalities in CAMT-MPL was higher than described so far. Most of the anomalies were related to the head region (brain anomalies, ocular and orbital anomalies) and consequences of intracranial bleedings. The present study demonstrates a higher variability of clinical courses than described so far and has important implications on diagnosis and therapy. The diagnosis CAMT-MPL has to be considered even for those patients who are inconspicuous in the first months of life or show somatic anomalies typical for other inherited bone marrow failure syndromes.

Treatment of telomeropathies

Telomeropathies or telomere biology disorders (TBDs) are a group of rare diseases characterised by altered telomere maintenance. Most patients with TBDs show pathogenic variants of genes that encode factors involved in the prevention of telomere shortening. Particularly in adults, TBDs mostly present themselves with heterogeneous clinical features that often include bone marrow failure, hepatopathies, interstitial lung disease and other organ sites. Different degrees of severity are also observed among patients with TBDs, ranging from very severe syndromes manifesting themselves in early childhood, such as Revesz syndrome, Hoyeraal-Hreidarsson syndrome, and Coats plus disease, to dyskeratosis congenita (DKC) and adult-onset "cryptic" forms of TBD, which often affect fewer organ systems. Overall, the most relevant clinical complications of TBD are bone marrow failure, lung fibrosis, and liver cirrhosis. In this review, we summarise recent advances in the management and treatment of TBD and provide a brief overview of the various treatment approaches.

A Case of Presumed Dyskeratosis Congenita Causing Severe Retinal Vascular Occlusion

Dyskeratosis congenita (DKC) is a rare, multisystem, bone marrow failure disease characterized by abnormalities such as in the skin, mucosa, nervous system, and lungs. Here we report a rare case of presumed DKC causing total retinal detachment in the right eye and severe peripheral retinal vascular occlusion in the left eye. A 3-year-old boy was presented with vitreous hemorrhage and total retinal detachment in the right eye and was scheduled to undergo vitreous surgery in the right eye and detailed ophthalmologic examination of the left eye under general anesthesia. Since a systemic examination revealed anemia and marked thrombocytopenia, he underwent a detailed pediatric examination. Although genetic testing revealed no significant pathologic mutations, the presence of shortened telomere length and other clinical findings suggested the possibility of DKC. His right eye had severe proliferative vitreoretinopathy, and retinal reattachment was not achieved with vitreous surgery, thus resulting in phthisis bulbi. The left eye showed a wide retinal avascular area in the temporal retina, retinal neovascularization, and hard exudates on fluorescein fundus angiography and was treated with laser photocoagulation using a binocular indirect ophthalmoscopic photocoagulator. Following laser surgery, the new blood vessels regressed, and the visual acuity was maintained at 1.0. The findings in this rare case indicate that DKC can cause severe retinal vascular occlusion, thus leading to vitreous hemorrhage and retinal detachment. Therefore, early detection with fundus examination and early treatment with photocoagulation are important.

Ubiquitous Chromatin Modifiers in Congenital Retinal Diseases: Implications for Disease Modeling and Regenerative Medicine

Retinal congenital malformations known as microphthalmia, anophthalmia, and coloboma (MAC) are associated with alterations in genes encoding epigenetic proteins that modify chromatin. We review newly discovered functions of such chromatin modifiers in retinal development and discuss the role of epigenetics in MAC in humans and animal models. Further, we highlight how advances in epigenomic technologies provide foundational and regenerative medicine-related insights into blinding disorders. Combining knowledge of epigenetics and pluripotent stem cells (PSCs) is a promising avenue because epigenetic factors cooperate with eye field transcription factors (EFTFs) to direct PSC fate - a foundation for congenital retinal disease modeling and cell therapy.

Transcriptome from opaque cornea of Fanconi anemia patient uncovers fibrosis and two connected players

Congenital corneal opacities (CCO) are a group of blinding corneal disorders, where the underlying molecular mechanisms are poorly understood. Phenotyping through specialized imaging and histopathology analysis, together with assessment of key transcriptomic changes (including glycosaminoglycan metabolic enzymes) in cornea(s) with CCO from a case of Fanconi anemia is the approach taken in this study to identify causal mechanisms. Based on our findings, we propose a novel mechanism and two key players contributing to CCO.

Revesz syndrome revisited

Background

Revesz syndrome (RS) is an extremely rare variant of dyskeratosis congenita (DKC) with only anecdotal reports in the literature.

Methods

To further characterize the typical features and natural course of the disease, we screened the English literature and summarized the clinical and epidemiological features of previously published RS cases. In addition, we herein describe the first recorded patient in central Europe.

Results

The literature review included 18 children. Clinical features are summarized, indicating a low prevalence of the classical DKC triad. All patients experienced early bone marrow failure, in most cases within the second year of life (median age 1.5 years; 95% CI 1.4–1.6). Retinopathy occurred typically between 6 and 18 months of age (median age 1.1 years; 95% CI 0.7–1.5). The incidence of seizures was low and was present in an estimated 20% of patients. The onset of seizures was exclusively during early childhood. The Kaplan–Meier estimate of survival was dismal (median survival 6.5 years; 95% CI 3.6–9.4), and none of the patients survived beyond the age of 12 years. Stem cell transplantation (SCT) was performed in eight children, and after a median of 22 months from SCT four of these patients were alive at the last follow up visit.

Conclusion

RS is a severe variant of DKC with early bone marrow failure and retinopathy in all patients. Survival is dismal, but stem cell transplantation may be performed successfully and might improve prognosis in the future.

Dyskeratosis congenita: a literature review

Dyskeratosis congenita is a rare hereditary disease that occurs predominantly in males and manifests clinically as the classic triad of reticulate hyperpigmentation, nail dystrophy and leukoplakia. It increases the risk of malignancy and other potentially lethal complications such as bone marrow failure, lung and liver diseases. Mutations in 19 genes are associated with dyskeratosis congenita, and a fifth of the pathogenic mutations are found in DKC1, the gene coding for dyskerin. This review aims to address the clinical and genetic aspects of the disease.

Inflammatory manifestations in patients with Shwachman-Diamond syndrome: A novel phenotype

Shwachman-Diamond syndrome (SDS) is an autosomal recessive multisystem disorder characterized by exocrine pancreatic dysfunction, bone marrow failure, and leukemia predisposition. Approximately 90% of cases are due to biallelic mutations in the Shwachman-Bodian-Diamond (SBDS) gene. Additional phenotypic features variably associated with SDS include skeletal, neurologic, hepatic, cardiac, endocrine, and dental abnormalities. We report five subjects with SDS who developed a range of inflammatory manifestations. Three patients developed inflammatory eye conditions. Single cases of juvenile idiopathic arthritis, chronic recurrent multifocal osteomyelitis, and scleroderma were also noted. Clinical presentation and treatment responses are described. Proteomic analysis revealed increased inflammatory signatures in SDS subjects as compared to controls. Treatment of inflammatory manifestations in patients with SDS may be complicated by potential myelosuppressive toxicities of anti-rheumatic medications. Further research is needed to better understand the potential link between inflammatory disorders and SDS to inform effective treatment strategies.

An update on the biology and management of dyskeratosis congenita and related telomere biology disorders

Introduction: Telomere biology disorders (TBDs) encompass a group of illnesses caused by germline mutations in genes regulating telomere maintenance, resulting in very short telomeres. Possible TBD manifestations range from complex multisystem disorders with onset in childhood such as dyskeratosis congenita (DC), Hoyeraal-Hreidarsson syndrome, Revesz syndrome and Coats plus to adults presenting with one or two DC-related features.Areas covered: The discovery of multiple genetic causes and inheritance patterns has led to the recognition of a spectrum of clinical features affecting multiple organ systems. Patients with DC and associated TBDs are at high risk of bone marrow failure, cancer, liver and pulmonary disease. Recently, vascular diseases, including pulmonary arteriovenous malformations and gastrointestinal telangiectasias, have been recognized as additional manifestations. Diagnostics include detection of very short leukocyte telomeres and germline genetic testing. Hematopoietic cell transplantation and lung transplantation are the only current therapeutic modalities but are complicated by numerous comorbidities. This review summarizes the pathophysiology underlying TBDs, associated clinical features, management recommendations and therapeutic options.Expert opinion: Understanding TBDs as complex, multisystem disorders with a heterogenous genetic background and diverse phenotypes, highlights the importance of clinical surveillance and the urgent need to develop new therapeutic strategies to improve health outcomes.

Dyskeratosis Congenita and Corneal Refractive Surgery

Dyskeratosis congenita is a syndrome of bone marrow failure secondary to unstable telomeres. It is characterized by a range of mucocutaneous diseases. Due to premature telomere shortening, these patients have limbal stem cell deficiency leading to poor regeneration and maintenance of the cornea. Many of these patients will require hematopoietic stem cell transplant in their lifetime, which poses a significant risk for acute and chronic graft-versus-host disease with and without ocular manifestations. We advise against elective corneal refractive surgery in patients with dyskeratosis congenita due to the compounded and long-term risks of delayed healing secondary to limbal stem cell deficiency and ocular complications of graft-versus-host disease post-allogeneic hematopoietic stem cell transplant.

The Spatiotemporal Pattern and Intensity of p53 Activation Dictates Phenotypic Diversity in p53-Driven Developmental Syndromes

Inappropriate activation of the p53 transcription factor contributes to numerous developmental syndromes characterized by distinct constellations of phenotypes. How p53 drives exquisitely specific sets of symptoms in diverse syndromes, however, remains enigmatic. Here, we deconvolute the basis of p53-driven developmental syndromes by leveraging an array of mouse strains to modulate the spatial expression pattern, temporal profile, and magnitude of p53 activation during embryogenesis. We demonstrate that inappropriate p53 activation in the neural crest, facial ectoderm, anterior heart field, and endothelium induces distinct spectra of phenotypes. Moreover, altering the timing and degree of p53 hyperactivation substantially affects the phenotypic outcomes. Phenotypes are associated with p53-driven cell-cycle arrest or apoptosis, depending on the cell type, with gene expression programs, rather than extent of mitochondrial priming, largely governing the specific response. Together, our findings provide a critical framework for decoding the role of p53 as a mediator of diverse developmental syndromes.

Late exudative retinopathy after laser treatment for retinopathy of prematurity in a child with dyskeratosis congenita

Exudative retinopathy may be a manifestation of a variety of isolated ocular or systemic diseases in children. We report the case of a teenager with dyskeratosis congenita who developed a unilateral late exudative retinopathy after having previous laser treatment for threshold retinopathy of prematurity as an infant.

Syndromic and Nonsyndromic Systemic Associations of Congenital Lacrimal Drainage Anomalies: A Major Review

PURPOSE

To review and summarize the syndromic, nonsyndromic, and systemic associations of congenital lacrimal drainage anomalies.

METHODS

The authors performed a PubMed search of all articles published in English on congenital lacrimal anomalies (1933-2016). Patients of these articles were reviewed along with the literature of direct references to syndromes and other systemic associations. Data reviewed included syndromic descriptions, systemic details, demographics, lacrimal presentations, management, and outcomes.

RESULTS

Syndromic and systemic associations with congenital lacrimal drainage disorders are not known to be common. Although familial presentations have been reported, the inheritance patterns are unclear for most anomalies. There is an increasingly growing evidence of a genetic basis to many lacrimal anomalies. However, few syndromes have either widespread or are frequently associated with lacrimal anomalies. Few sequences of distinct lacrimal presentations and intraoperative findings are seen. Surgical challenges in these patients are distinct and a thorough pre and intraoperative anatomical assessment, detailed imaging when indicated, and assessment and correction of associated periocular and facial abnormalities may facilitate good outcomes.

CONCLUSIONS

Lacrimal drainage anomalies associated with syndromic and nonsyndromic systemic conditions have certain unique features of their own and their surgical and anesthesia challenges are distinct. Diagnosis of congenital lacrimal drainage anomalies should prompt consideration of the possible presence of associated systemic abnormalities.

Revesz syndrome masquerading as traumatic retinal detachment

A 13-month-old boy with mild hemophilia A presented for strabismus evaluation and was found to have retinal hemorrhages in the right eye, left exotropia, and left total retinal detachment. These findings were attributed to trauma and hemophilia A. Routine blood work for hemophilia A subsequently showed pancytopenia. A bone marrow aspirate showed marked hypocellularity consistent with severe aplastic anemia, and telomere testing revealed very short telomeres. The patient was found to have a TINF2 mutation consistent with a diagnosis of Revesz syndrome, a variant of dyskeratosis congenita. He underwent successful bone marrow transplantation, and on subsequent evaluation was found to have retinal hemorrhages, vessel sclerosis, and cotton wool spots in the right eye associated with peripheral retinal nonperfusion. He underwent retinal laser treatment to the areas of retinal nonperfusion which resulted in stable visual function.

Fanconi Anemia: A Rarely Considered Cause of Macrocytosis During Childhood

We describe a Turkish boy newly diagnosed with Fanconi anemia with mutation in the FANCA gene. The patient, with normal clinical phenotype and negative chromosomal breakage test result, presented with macrocytosis. No clinical or laboratory changes were observed in a follow-up period of 4 years. The diagnosis was confirmed molecularly after a prolonged and exhaustive investigation. He was found to be a compound heterozygote for 2 mutations in the FANCA gene (1 of which is novel, c.4261-2A>C). We present this experience to alert physicians that Fanconi anemia should be considered in the differential diagnosis of otherwise unexplained macrocytosis during childhood.

PERIPHERAL RETINOPATHY ASSOCIATED WITH APLASTIC ANEMIA

PURPOSE

To report a case of severe, bilateral, rapidly progressing peripheral retinal nonperfusion associated with underlying aplastic anemia.

METHODS

An interventional case report.

RESULTS

A 4-year-old girl presented with decreased visual acuity. On clinical examination, she was found to have a RAPD, elevated intraocular pressure, 360° rubeosis, vitreous hemorrhage, severe exudative retinal detachment, and telangiectasia with severe peripheral retinal nonperfusion. Laboratory workup was significant for pancytopenia, and a bone marrow biopsy showed extreme hypocellularity with no malignant cells. The patient was diagnosed with primary aplastic anemia. She developed dramatic progression of retinal nonperfusion in the left eye, as well as in the fellow right eye. This bilateral retinopathy was poorly responsive to aggressive management, which included laser photocoagulation and intravitreal injections of anti-vascular endothelial growth factor medications.

CONCLUSION

Asymmetric, bilateral quickly progressing peripheral retinal ischemia, in conjunction with pancytopenia and otherwise negative workup may be related to underlying bone marrow failure and aplastic anemia.

RETINAL VASCULAR TORTUOSITY AND EXUDATIVE RETINOPATHY IN A FAMILY WITH DYSKERATOSIS CONGENITA MASQUERADING AS FAMILIAL EXUDATIVE VITREORETINOPATHY

PURPOSE

To report a novel presentation of dyskeratosis congenita masquerading as familial exudative vitreoretinopathy.

METHODS

Observational case series involving single family and literature review.

RESULTS

A brother and sister were diagnosed with familial exudative vitreoretinopathy at ages 4 and 2, respectively. Both patients were managed with laser photocoagulation. Eight years after the initial presentation, both siblings developed pancytopenia secondary to bone marrow failure. Laboratory work-up revealed severely shortened telomere length in both patients, and genetic testing revealed a missense mutation in the gene that encodes the reverse transcriptase component of telomerase, confirming the diagnosis of dyskeratosis congenita. The father of both children was a carrier of the same mutation, who exhibited marked retinal vascular tortuosity of the second-order vessels.

CONCLUSION

Dyskeratosis congenita is a severe multisystem disorder, which should be considered in cases of pediatric exudative retinopathies with concurrent signs and/or symptoms of bone marrow failure.

Bilateral Proliferative Retinopathy Associated With Hoyeraal-Hreidarsson Syndrome, a Severe Form of Dyskeratosis Congenita

Dyskeratosis congenita (DC) is the prototypical member of a family of diseases caused by defective telomere maintenance. These "telomeropathies" also include Hoyeraal-Hreidarsson syndrome (HH) and Revesz syndrome, which are severe forms of dyskeratosis congenita, as well as a subset of idiopathic pulmonary fibrosis, aplastic anemia, and Coats' plus syndrome. Retinopathy has only rarely been reported in DC and HH, but is universally present in Coats' plus and Revesz syndromes. The care of these patients is typically a multidisciplinary effort, and this should include monitoring by an ophthalmologist.

Thinking of VACTERL-H? Rule out Fanconi Anemia according to PHENOS

VACTERL-H association includes three of eight features: vertebral anomalies, anal atresia, congenital heart disease, tracheo-esophageal fistula, esophageal atresia, renal, limb anomalies, and hydrocephalus. The VACTERL-H phenotype among cases with FA is considered to be about 5%; the frequency of FA among patients with VACTERL-H is unknown. We examined 54 patients with FA in the National Cancer Institute Inherited Bone Marrow Failure Syndrome Cohort for features of VACTERL-H, including imaging studies (radiology and ultrasound). Eighteen of the fifty-four patients had three or more VACTERL-H features. The presence of VACTERL-H association in 33% of those with FA is much higher than the previous estimate of 5% (P < 0.0001). We created the acronym PHENOS (Pigmentation, small Head, small Eyes, central Nervous system (not hydrocephalus), Otology, and Short stature) which includes all major phenotypic features of FA that are not in VACTERL-H; these findings were more frequent in the patients with FA who had VACTERL-H. Identification of any components of the VACTERL-H association should lead to imaging studies, and to consideration of the diagnosis of FA, particularly if the patient has radial ray and renal anomalies, as well as many features of PHENOS. There was no association of the presence or absence of VACTERL-H with development of cancer, stem cell transplant, or survival. Early diagnosis will lead to genetic counseling and early surveillance and management of complications of FA. © 2016 Wiley Periodicals, Inc.

Frosted Branch Angiitis in Pediatric Dyskeratosis Congenita: A Case Report

Dyskeratosis congenita (DC) is an inherited bone marrow failure syndrome, usually presented with abnormal skin pigmentation, nail dystrophy, and oral leukoplakia. The main cause of mortality in DC is immunodeficiency and vital infection. DC involves multisystem, but retinal involvements are rare.Herein, we report an unusual case of pediatric DC suffering from frosted branch angiitis (FBA) after recovery of mycoplasma pneumonia. Cytomegalovirus infection and cytokine changes were found relevant to the onset of FBA. Despite corticosteroids, antiviral medication, and hematopoietic stem cell transplantation, the patient ended in poor vision with optic atrophy.This case implies that pediatricians should be aware of FBA as a rare retinal manifestation in children with DC and bone marrow failure. Cytomegalovirus may be one of the common causes and cytokines could be triggering factors.

Pigmentary disorders of the eyes and skin

Oculocutaneous albinism, Menkes syndrome, tuberous sclerosis, neurofibromatosis type 1, dyskeratosis congenita, lentiginosis profusa syndrome, incontinentia pigmenti, and Waardenburg syndrome all are genodermatoses that have well established gene mutations affecting multiple biological pathways, including melanin synthesis, copper transport, cellular proliferation, telomerase function, apoptosis, and melanocyte biology. Onchocerciasis results from a systemic inflammatory response to a nematode infection. Hypomelanosis of Ito is caused by chromosomal mosaicism, which underlies its phenotypic heterogeneity. Incomplete migration of melanocytes to the epidermis and other organs is the underlying feature of nevus of Ota. Vogt-Koyangi-Harada and vitiligo have an autoimmune etiology; the former is associated with considerable multiorgan involvement, while the latter is predominantly skin-limited.

Ocular manifestations of genetic skin disorders

Genetic skin diseases, or genodermatoses, often have extracutaneous manifestations. Ocular manifestations in particular can have significant clinical implications, like blindness. Other manifestations, such as the corneal opacities that occur in X-linked ichthyosis, are asymptomatic but characteristic of a particular genodermatosis. Ophthalmologic examination can aid in diagnosis when characteristic findings are seen. The genodermatoses with ocular manifestations will be reviewed, but neurocutaneous, syndromes, genetic pigmentary disorders, and genetic metabolic diseases are not included because they are covered elsewhere in this issue.

FANCONI ANEMIA PRESENTING AS BILATERAL DIFFUSE RETINAL OCCLUSIVE VASCULOPATHY

PURPOSE

To describe the ocular findings and subsequent workup of a 21-year-old woman with previously undiagnosed Fanconi anemia.

METHODS

Observational case report and literature review.

RESULTS

A 21-year-old healthy woman presented with bilateral retinal hemorrhages, telangiectasia, and severe ischemia with vascular leak. Systemic workup revealed anemia and thrombocytopenia. A diepoxybutane chromosomal breakage test confirmed the diagnosis of Fanconi anemia.

CONCLUSION

Ocular complications are common in patients with Fanconi anemia and may be the presenting manifestation of the disease.

Dyskeratosis Congenita Without Oral Involvement: A Rare Hereditary Disease

Dyskeratosis congenita (DC) is a rare, progressive, multi-system, inherited disorder of telomere biology, first described in 1906 as the Zinsser-Engman-Cole syndrome. The condition presents with the classic triad of nail dystrophy, reticulate skin pigmentation, and oral leukoplakia. Variable somatic abnormalities may be present; these include pulmonary, gastrointestinal, genitourinary, cerebral, and dental complications. Pancytopenia eventually develops, progressing to bone marrow failure. In our patient, the progression of DC did not follow the "classic triad" typically seen in the condition. Here we report the case of a 27-year-old male who had features consistent with this syndrome but who had a normal oral cavity associated with aplastic anemia for which longstanding nail dystrophy and reticular pigmentation were the dominant clinical features. The patient was advised to avoid smoking and severe exposure to the sun, and to return regularly for follow-up. Because all symptoms of this disorder are not necessarily seen collectively in any one patient, physicians should consider it as a probability in all patients showing signs of reticular hyperpigmentation, especially accompanied by aplastic anemia. Our report emphasizes the fact that not all components of the syndrome need to be present and in all cases of genodermatosis, pleomorphism may be expected with variable clinical manifestations. Even though many variants have been described in literature, sparing of the oral cavity as in our patient is extremely uncommon. Therefore, physicians should be aware of the mucocutaneous manifestation of DC and its diagnosis and refer the patient for better evaluation.

Adult-onset Diamond-Blackfan anemia with a novel mutation in the exon 5 of RPL11: too late and too rare

Diamond-Blackfan anemia (DBA) is a congenital erythroid aplasia usually diagnosed in the early infancy and associated with mutations or large deletions in 11 ribosomal protein (RP) genes. Adult patients with severe, transfusion dependence, aregenerative anemia might have a genetic-in-origin disease with an atypical presentation. Late onset nonclassical DBA should be ruled out and mutations of RP genes studied.

Dyskeratosis congenita caused by a novel TERT point mutation in siblings with pancytopenia and exudative retinopathy

Two siblings presenting with exudative retinopathy, thrombocytopenia, and macrocytosis were found to have markedly shortened telomeres and a previously unreported inherited mutation in TERT, c.2603A>G. Revesz syndrome, a subtype of dyskeratosis congenita (DC) caused by TINF2 mutation, combines marrow failure with exudative retinopathy, intracranial calcifications, and neurocognitive impairment. As our patients manifested neither intracranial calcification nor significant neurocognitive impairment, we conclude that the c.2603A>G TERT mutation may define a subtype of DC manifesting first as exudative retinopathy without other signs of DC. Children with exudative retinopathy should be periodically screened for macrocytosis and cytopenias to evaluate for underlying DC.

Ocular dimensions in relation to auxological data in a sample of Swedish children aged 4-15 years

PURPOSE

The purpose was to characterize normal growth patterns of ocular and optical components and to relate them to auxological data in a sample of Swedish children aged 4-15 years.

METHODS

A prospective cross-sectional study was carried out in 143 Swedish children with a mean age of 9.8 years. Variables including gestational age (GA), weight, length and head circumference (HCF) at birth and at the time of assessment were registered. Visual acuity (VA), cycloplegic refraction and biometric measures were obtained. Palpebral fissure length and inner canthal distance were measured. Optic disc morphology as seen on fundus photographs was analysed.

RESULTS

Children born more mature, with male predilection, were found to have deeper anterior and vitreous chamber depths, longer axial lengths and thinner crystalline lens thickness. No correlations were found between ocular biometric measurements and VA or refraction after adjustment for confounding variables. Inner canthal distance was significantly correlated with birth length (p = 0.03), height, weight, BMI and HCF (p = 0.0008, p = 0.0007, p = 0.037, and p = 0.04, respectively) at time of assessment. Total axial length was found to be significantly correlated with GA (p = 0.0226) and length at assessment in girls (p = 0.0084). Right optic disc and rim areas decreased with increasing age (p = 0.0078 and p = 0.0107, respectively); however, optic disc parameters were not dependent on any other variable.

CONCLUSION

These normative values may serve as a basis for the ocular findings and their relationship to auxological data in Caucasian children aged 4-15 years, as well as for future comparison in patients with paediatric ocular pathologies.

Coats disease in a patient with Fanconi anemia: a case report

PURPOSE

To describe the diagnosis and management of Coats disease in a patient with Fanconi anemia.

METHODS

Case report.

RESULTS

A 12-year-old girl with Fanconi anemia developed Coats disease. Retinal vasculature anomalies are present in both diseases; however, differential diagnosis in this case could be based on the presence of telangiectasias, which are typical of Coats disease, and the absence of perivascular sheathing, usually described in the uncommon retinal manifestations of Fanconi anemia. The stage 4 Coats disease was managed with intravitreal bevacizumab injections and later pars plana vitrectomy with silicone oil tamponade surgery, which prevented enucleation despite visual loss.

CONCLUSIONS

Patients with Fanconi anemia can have retinal vasculature anomalies that are not necessarily related to this systemic anomaly. In this case, the retinal alterations were related to advanced Coats disease stage, which was successfully treated, and enucleation of the affected eye was not necessary.

Ocular manifestations of idiopathic aplastic anemia: retrospective study and literature review

Aplastic anemia (AA) is a rare disease with few reports on its ophthalmic manifestations. The ocular findings are described in a retrospective consecutive series of 719 AA Korean patients followed at the Hematology Clinic of The Catholic University of Korea. Out of a total of 719 patients, 269 patients had eye examinations, 156 patients had retinal evaluation, and 37 (23.7%) had retinal findings. These 37 patients had unilateral retinal hemorrhage in seven and bilateral retinal hemorrhage in 30 with mean hemoglobin of 6.6 g/dL (range 2.7–12.6 g/dL) and platelet counts of 18.8×10⁹/L (range 4–157×10⁹/L); central retinal vein occlusion-like picture occurred in nine patients and these had similar rheology to the rest of the subjects; optic disc edema, cotton-wool spots, macular edema, and dry eyes occurred in two, three, five, and three patients, respectively. In this Korean series of 141 subjects with AA, systemic bleeding occurred in 24.8% of subjects, retinal hemorrhage in 37% of subjects, and any bleeding site (eye or elsewhere) occurred in 47.5% of subjects with AA. A literature review (1958–2010) of 200 AA cases revealed retinal hemorrhages in 56%, subhyaloid or vitreous hemorrhage in 9%, peripheral retinal vasculopathy in 5.5%, and cotton-wool spots, Sjögren’s syndrome, or optic disc edema in 4% each. The prevalence of retinopathy among series of AA patients varied from 20% to 28.3%, which is consistent with the Korean series of 24.8%. Management of AA patients needs to involve multiple specialties, including hematologists, ophthalmologists, and infectious disease specialists.

Ocular manifestations and visual functions in patients with Fanconi anaemia

PURPOSE

Fanconi anaemia (FA) is a multisystemic disorder with ocular implications. This study aims to describe visual function, ocular characteristics and visual processing skills in patients with FA after haematopoietic stem cell transplantation.

METHODS

Ten patients with FA, ages 8-17 years, underwent ophthalmological examinations, corneal, periocular and fundus photography, visual evoked potentials (VEPs), visual fields and ocular motor and visual processing information tests.

RESULTS

Best-corrected decimal visual acuity was ≥0.65 in all 20 eyes. Microcornea was present in 18 of 18 eyes, short axial lengths in six of six eyes, steep corneal curvatures in four of six eyes, ptosis in 14 of 16 eyes, short palpebral fissures in 15 of 16 eyes and hypotelorism in three of seven patients. Optic disc areas were smaller in patients with FA compared to controls (p = 0.0003 right, p = 0.0003 left eye). Visual fields were abnormal in 4 of 18 eyes, while VEP was abnormal in 1 of 20 eyes. Eight patients had ocular motor dysfunction, while nine of 10 patients showed delay in visual processing skills.

CONCLUSION

Patients with FA can present with microcornea, microphthalmia, ptosis, steep corneal curvatures, small optic discs, ptosis and delay in visual processing skills. Detailed ophthalmological and visual processing skills assessments and developmental investigations are important to detect impairments and facilitate appropriate support.

Human telomeres and telomere biology disorders

Telomeres consist of long nucleotide repeats and a protein complex at chromosome ends essential for chromosome stability. Telomeres shorten with each cell division and thus are markers of cellular age. Dyskeratosis congenita (DC) is a cancer-prone inherited bone marrow failure syndrome caused by germ-line mutations in key telomere biology genes that result in extremely short telomeres. The triad of nail dysplasia, abnormal skin pigmentation, and oral leukoplakia is diagnostic of DC but highly variable. Patients with DC may also have but numerous other medical problems, including pulmonary fibrosis, liver abnormalities, avascular necrosis of the hips, and stenosis of the esophagus, lacrimal ducts, and/or urethra. All modes of inheritance have been reported in DC and de novo mutations are common. Broad phenotypic heterogeneity occurs within DC. Clinically severe variants of DC are Hoyeraal-Hreidarsson syndrome and Revesz syndrome. Coats plus syndrome joined the spectrum of DC with the discovery that it is caused by mutations in a telomere-capping gene. Less clinically severe variants, such as subsets of apparently isolated aplastic anemia or pulmonary fibrosis, have also been recognized. These patients may not have the DC-associated mucocutaneous triad or complicated medical features, but they do have the same underlying genetic etiology. This has led to the use of the descriptive term telomere biology disorder (TBD). This chapter will review the connection between telomere biology and human disease through the examples of DC and its related TBDs.

Updates on the biology and management of dyskeratosis congenita and related telomere biology disorders

Dyskeratosis congenita (DC) is a cancer-prone inherited bone marrow failure syndrome caused by aberrant telomere biology. The mucocutaneous triad of nail dysplasia, abnormal skin pigmentation and oral leukoplakia is diagnostic, but is not always present; DC can also be diagnosed by the presence of very short leukocyte telomeres. Patients with DC are at high risk of bone marrow failure, pulmonary fibrosis, liver disease, cancer and other medical problems. Germline mutations in one of nine genes associated with telomere maintenance are present in approximately 60% of patients. DC is one among the group of clinically and biologically related telomere biology disorders, including Hoyeraal-Hreidarsson syndrome, Revesz syndrome, Coats plus (also known as cranioretinal microangiopathy with calcifications and cysts) and subsets of aplastic anemia, pulmonary fibrosis, nonalcoholic and noninfectious liver disease and leukemia. The authors review the pathobiology that connects DC and the related telomere biology disorders, methods of diagnosis and management modalities.