Ophthalmic and molecular genetic findings in Kniest dysplasia

Ophthalmic manifestations of Czech dysplasia

Czech dysplasia is an autosomal dominant type 2 collagenopathy that is caused by heterozygosity for the recurrent p.(Arg275Cys) COL2A1 variant. Affected individuals usually present with skeletal abnormalities such as metatarsal hypoplasia of the third and fourth toes and early-onset arthropathy, as well as hearing loss. To date, no ophthalmic findings have been reported in patients with Czech dysplasia even though COL2A1 has been implicated in other ocular conditions such as type 1 Stickler syndrome. For the first time, we report the ocular findings in four families with Czech dysplasia, including type 1 vitreous anomaly, hypoplastic vitreous, retinal tears, and significant refractive error. These novel ocular findings expand the phenotype associated with Czech dysplasia and may aid clinicians as an additional diagnostic feature. Patients with congenital abnormalities of vitreous gel architecture have an increased risk of retinal detachment, and as such, patients may benefit from prophylaxis. Considering that many of the patients did not report any ocular symptoms, vitreous phenotyping is of key importance in identifying the need for counseling with regard to prophylaxis.

Restoration of vision in Kniest dysplasia patient characterized by retinal detachment with dialysis of the ora serrata: A case report

INTRODUCTION

Congenital eye diseases have a significant impact on children and young adults. Retinal detachment associated with Kniest dysplasia represents the most severe ocular complication, which is challenging to diagnose and treat effectively. Genetic testing has emerged as an invaluable tool for diagnosing hereditary diseases.

CASE PRESENTATION

A 23-year-old male presented to our Ophthalmology Clinic with retinal detachment involving dialysis of the ora serrata in his left eye. High-throughput exon sequencing enabled a definitive diagnosis of Kniest dysplasia resulting from a mutation in the COL2A1 gene. The patient subsequently underwent pars plana vitrectomy with silicone oil injection to reattach the retina. This surgical intervention successfully reattached the retina and restored vision to 20/25 in the affected eye.

CONCLUSION

Retinal detachment represents the most serious ocular complication associated with Kniest dysplasia. To prevent permanent blindness, early diagnosis through genetic testing and regular ophthalmological examinations are imperative. Advances in genetic screening have improved the management of retinal detachment risk in Kniest dysplasia patients.

The genetics and disease mechanisms of rhegmatogenous retinal detachment

Rhegmatogenous retinal detachment (RRD) is a sight threatening condition that warrants immediate surgical intervention. To date, 29 genes have been associated with monogenic disorders involving RRD. In addition, RRD can occur as a multifactorial disease through a combined effect of multiple genetic variants and non-genetic risk factors. In this review, we provide a comprehensive overview of the spectrum of hereditary disorders involving RRD. We discuss genotype-phenotype correlations of these monogenic disorders, and describe genetic variants associated with RRD through multifactorial inheritance. Furthermore, we evaluate our current understanding of the molecular disease mechanisms of RRD-associated genetic variants on collagen proteins, proteoglycan versican, and the TGF-β pathway. Finally, we review the role of genetics in patient management and prevention of RRD. We provide recommendations for genetic testing and prophylaxis of at-risk patients, and hypothesize on novel therapeutic approaches beyond surgical intervention.

Reduction Mammaplasty in a Patient with Kniest Dysplasia: Case Report and Literature Review

Collagen plays a fundamental role in wound healing and consequently defective collagen can impair normal wound healing processes. Kniest dysplasia (KD) is a collagenopathy that results from a pathogenic mutation in a gene that codes for type II collagen. Clinical manifestations of the dysplasia include short-trunk dwarfism, kyphoscoliosis, hand arthropathy, cleft palate, hearing loss, and ocular abnormalities. We present the case of a 21-year-old woman who desired reduction mammaplasty. A review of the literature was performed, and there were no published reports of any plastic surgery procedures in patients with KD. The patient proceeded with surgery and healed without any complications. Given that wound healing appears normal in this patient population, it is reasonable to consider elective plastic surgical procedures in patients with KD.

Therapeutic and diagnostic advances in Stickler syndrome

The Stickler syndromes are the leading cause of inherited retinal detachment and the most common cause of rhegmatogenous retinal detachment in childhood. The clinical and molecular genetic spectrum of this connective tissue disorder is discussed in this article, emphasising the key role the ophthalmologist has to play in the identification, diagnosis and prevention of blindness in the increasingly widely recognised sub-groups with ocular-only (or minimal systemic) involvement. Without diagnosis and prophylaxis in such high-risk subgroups, these patients are at high risk of Giant Retinal Tear detachment and blindness, especially in the paediatric population, where late or second eye involvement is common. Initially considered a monogenic disorder, there are now known to be at least 11 distinct phenotypic subgroups in addition to allied connective tissue disorders that can present to the clinician as part of the differential diagnosis.

Plain language summary

Treatment and diagnostic advances in Stickler syndrome The Stickler syndromes are a group of related connective tissue disorders that are associated with short-sight and a very high risk of blindness from detachment of the retina - the light sensitive film at the back of the eye. Other features include cleft palate, deafness and premature arthritis. It is the most common cause of retinal detachment in children and the most common cause of familial or inherited retinal detachment. In contrast to most other forms of blinding genetic eye disease, blindness from retinal detachment in Stickler syndrome is largely avoidable with accurate diagnosis and prophylactic (preventive) surgery. Recent advances in the understanding of the genetic causes of Stickler syndrome mean that the diagnosis can now be confirmed in over 95% of cases and, most importantly, the patient's individual risk of retinal detachment can be graded. Preventative surgery is hugely effective in reducing the incidence of retinal detachment in those patients shown to be at high risk. NHS England have led the way in the multidisciplinary care for patients with Stickler syndrome by launching a highly specialist service that has been free at point of care to all NHS patients in England since 2011 (https://www.england.nhs.uk/commissioning/spec-services/highly-spec-services, www.vitreoretinalservice.org).

Orthodontic Treatment in a Patient With Kniest Dysplasia: A Case Study and Review of Literature

Kniest dysplasia is a rare autosomal dominant chondrodysplasia that is characterized by distinct musculoskeletal and craniofacial irregularities. These craniofacial abnormalities include cleft palate, midface anomalies, tracheomalacia, and hearing loss. This article illustrates a case of Kniest dysplasia that presented for orthodontic treatment. The purpose of this literature review is to describe clinical manifestations, radiographic features, histopathological features, genetic mutation, and management of Kniest dysplasia.

Stickler syndrome: exploring prophylaxis for retinal detachment

PURPOSE OF REVIEW

The literature regarding prophylactic treatment of rhegmatogenous retinal detachment in Stickler syndrome remains controversial. We review major published clinical studies and offer a critical analysis of this subject.

SUMMARY

Stickler syndrome is a systemic collagenopathy affecting multiple organ systems including the eye, ear, and skeleton. Stickler syndrome is probably the most common cause of genetically determined pediatric rhegmatogenous retinal detachment. Congenital developmental anomalies constitute over half rhegmatogenous detachments (RRD) in patients less than 10 years. The majority are caused by hereditary vitreoretinopathies associated with Stickler syndrome. Sixty percent of patients with Stickler syndrome develop RRD's over their lifetime with possible severe visual loss and subsequent lifelong morbidity. In view of these complications, some have emphasized the importance of prophylactic laser treatment to the retina of patients with Stickler syndrome to reduce the occurrence of and/or prevent future rhegmatogenous retinal detachment, but there appears to be insufficient data to support the absolute benefit of such prophylactic treatment. Guidelines regarding the age at prophylactic treatment as well as type and frequency of intervention are scarce and would benefit from additional clinical investigations.

Cyst of canal of Nuck in a young woman affected by kniest syndrome: ultrasound and MRI features

Swelling of the inguinal region in a woman is a frequent finding in daily clinical practice. We focused our attention on the possible differential diagnoses, giving emphasis to the less common causes of this frequent female disorder and describing their characteristics in ultrasound and magnetic resonance imaging. The causes of swelling in this region may be multiple and in this paper, we will show a rare case of diagnosis of Nuck's canal cyst in a patient with Kniest Syndrome.

Best practice guidelines regarding diagnosis and management of patients with type II collagen disorders

PURPOSE

Skeletal dysplasias comprise a heterogeneous group of inherited disorders of development, growth, and maintenance of the human skeleton. Because of their relative rarity and wide phenotypic variability, patients should be accurately identified, uniformly assessed, and managed by clinicians who are aware of their potential complications and possess the knowledge and resources to treat them effectively. This study presents expert guidelines developed to improve the diagnosis and management of patients with type II collagen skeletal disorders to optimize clinical outcomes.

METHODS

A panel of 11 multidisciplinary international experts in the field of skeletal dysplasia participated in a Delphi process, which comprised analysis of a thorough literature review with subsequent generation of 26 diagnosis and care recommendations, followed by two rounds of anonymous voting with an intervening face-to-face meeting. Those recommendations with more than 80% agreement were considered as consensual.

RESULTS

After the first voting round, consensus was reached to support 12 of 26 (46%) statements. After the panel discussion, the group reached consensus on 22 of 24 revised statements (92%).

CONCLUSIONS

Consensus-based, expert best practice guidelines developed as a standard of care to assist accurate diagnosis, minimize associated health risks, and improve clinical outcomes for patients with type II collagen skeletal dysplasias.

Evaluation of 10 AMD Associated Polymorphisms as a Cause of Choroidal Neovascularization in Highly Myopic Eyes

Choroidal neovascularization (CNV) commonly occurs in age related macular degeneration and pathological myopia patients. In this study we conducted a case-control prospective study including 431 participants. The aim of this study was to determine the potential association between 10 single nucleotide polymorphisms (SNPs) located in 4 different genetic regions (CFI, COL8A1, LIPC, and APOE), and choroidal neovascularization in age-related macular degeneration and the development of choroidal neovascularization in highly myopic eyes of a Caucasian population. Univariate and multivariate logistic regression analysis adjusted for age, sex and hypertension was performed for each allele, genotype and haplotype frequency analysis. We found that in the univariate analysis that both single-nucleotide polymorphisms in COL8A1 gene (rs13095226 and rs669676) together with age, sex and hypertension were significantly associated with myopic CNV development in Spanish patients (p<0.05). After correcting for multiple testing none of the polymorphisms studied remained significantly associated with myopic CNV (p>0.05); however, analysis of the axial length between genotypes of rs13095226 revealed an important influence of COL8A1 in the development of CNV in high myopia. Furthermore we conducted a meta-analysis of COL8A1, CFI and LIPC genes SNPs (rs669676, rs10033900 and rs10468017) and found that only rs669676 of these SNPs were associated with high myopia neovascularization.