MFRP variant results in nanophthalmos, retinitis pigmentosa, variability in foveal avascular zone.

BACKGROUND: Membrane frizzled-related protein (MFRP) plays a critical role in ocular development. MFRP mutations are known to cause nanophthalmos and, in some cases, retinitis pigmentosa, foveoschisis, and/or optic nerve head (ONH) drusen. The broad clinical spectrum of MFRP mutations necessitates further investigation of specific genotype-phenotype relationships. MATERIALS AND METHODS: We reviewed ophthalmologic and genetic medical records of two affected siblings and one unaffected sibling. RESULTS: Genetic testing revealed variants MFRP c.855T>A, p.(Cys285*) and MFRP c.1235T>C, p.(Leu412Pro) in trans in the two affected siblings. In both cases, photopic and scotopic responses were markedly reduced on electroretinogram (ERG), with greater decrease in scotopic function. Optical coherence tomography for both siblings revealed non-cystoid thickening. Blunted foveal reflexes were also observed in both siblings. Notably, foveal avascular zone abnormalities were seen on fundus autofluorescence in only one affected sibling. CONCLUSIONS: MFRP-related ocular disease may be underrecognized due to its presentation with high hyperopia and possibly subtle retinal findings. Presence of variants MFRP c.855T>A, p.(Cys285*) and MFRP c.1235T>C, p.(Leu412Pro) in trans resulted in nanophthalmos and retinitis pigmentosa without associated foveoschisis or ONH drusen in our patients, consistent with the incomplete phenotype previously described in Neri et al. Abnormalities in the foveal avascular zone have been noted in other case studies and were inconsistently associated with the variants described here, representing a potential area for future investigation.

The second Japanese family with Malattia Leventinese/Doyne honeycomb retinal dystrophy.

PURPOSE: To describe the clinical and genetic findings of patients in the second Japanese family with Malattia Leventinese/Doyne honeycomb retinal dystrophy (ML/DHRD). METHODS: Two patients (a 41-year-old male proband and his third son) underwent comprehensive ophthalmic examinations, including full-field and multifocal electroretinography (ERG). Sanger sequencing was performed to detect an EFEMP1 gene variant (p.Arg345Trp), which was identified as the only causative pathogenic variant. RESULTS: Genetic analysis revealed that both patients carried the heterozygous variant, but the other unaffected family members did not. Although the proband exhibited innumerable radially distributed drusen in both the posterior poles and good visual acuity at initial presentation, bilateral choroidal neovascularization (CNV) developed during the 15-year follow-up. The proband received 15 intravitreal anti-vascular endothelial growth factor (VEGF) injections in the left eye (LE) and two injections in the right eye (RE). At 56 years of age, his decimal best-corrected visual acuity was 0.1 and 1.2 in the LE and RE, respectively. Full-field ERG showed that while the rod and combined responses were within normal amplitudes, the cone and 30-Hz flicker responses had slightly decreased amplitudes. Multifocal ERG revealed attenuated central responses in the LE and decreased temporal responses in the RE. In the 20-year-old son, multifocal ERG showed normal responses in both eyes. CONCLUSION: This is the first report of ML/DHRD in a patient who developed bilateral CNV and received anti-VEGF treatment in both eyes. Although multifocal ERG exhibited worsening of macular function, the generalized photoreceptor function was preserved until middle age.

First reported case of Doyne honeycomb retinal dystrophy (Malattia Leventinese/autosomal dominant drusen) in Scandinavia.

BACKGROUND: Doyne honeycomb retinal dystrophy (DHRD)/malattia leventinese (ML) is an autosomal dominant, progressive retinal disorder characterized by massive central retinal drusen often partly coalescent forming a characteristic honeycomb-like pattern. Debut of vision loss often occurs in early to mid-adulthood, and the degree varies. A single variant in EFEMP1: c.1033C>T (R345W) has been identified as the cause in all cases. METHODS: Following DNA isolation, exome sequencing was performed in seven genes associated with flecked retina. Direct sequencing was used for variant verification. RESULTS: We report the first Scandinavian case of molecular genetically verified DHRD/ML: a 57-year-old woman debuting with vision loss and metamorphopsia. On both eyes, ophthalmological findings included massive hard drusen in the macular region and nasal to the optic disc as well as macular hyperpigmentation. Secondary choroidal neovascularizations were identified on both eyes, and anti-vascular endothelial growth factor was administered, without effect. CONCLUSION: Molecular genetic investigation revealed heterozygosity for the known pathogenic missense variant in EFEMP1: c.1033C>T (R345W) previously reported in relation to DHRD/ML. Family history revealed no other cases of similar visual impairment suggesting a de novo mutation. Furthermore, there was no correlation between the unique DHRD/ML haplotypes reported in the literature and our patient.

Clinically-identified C-terminal mutations in fibulin-3 are prone to misfolding and destabilization.

Distinct mutations in the secreted extracellular matrix protein, fibulin-3 (F3), have been associated with a number of ocular diseases ranging from primary open angle glaucoma to cuticular age-related macular degeneration to a rare macular dystrophy, Malattia Leventinese (ML). The R345W F3 mutation that causes ML leads to F3 misfolding, inefficient secretion and accumulation at higher intracellular steady state levels in cultured cells. Herein, we determined whether fifteen other clinically-identified F3 mutations also led to similar levels of misfolding and secretion defects, which might provide insight into their potential pathogenicity. Surprisingly, we found that only a single F3 variant, L451F, presented with a significant secretion defect (69.5 ± 2.4% of wild-type (WT) F3 levels) and a corresponding increase in intracellular levels (226.8 ± 25.4% of WT F3 levels). Upon follow-up studies, when this conserved residue (L451) was mutated to a charged (Asp or Arg) or bulky (Pro, Trp, Tyr) residue, F3 secretion was also compromised, indicating the importance of small side chains (Leu, Ala, or Gly) at this residue. To uncover potential inherent F3 instability not easily observed under typical culture conditions, we genetically eliminated the sole stabilizing N-linked glycosylation site (N249) from select clinically-identified F3 mutants. This removal exacerbated R345W and L451F secretion defects (19.8 ± 3.0% and 12.4 ± 1.2% of WT F3 levels, respectively), but also revealed a previously undiscovered secretion defect in another C-terminal variant, Y397H (42.0 ± 10.1% of WT F3 levels). Yet, glycan removal did not change the relative secretion of the N-terminal mutants tested (D49A, R140W, I220F). These results highlight the uniqueness and molecular similarities between the R345W and L451F variants and also suggest that previously identified disease-associated mutations (e.g., R140W) are indistinguishable from WT with respect to secretion, hinting that they may lead to disease by an alternative mechanism.

The Pathophysiological Significance of Fibulin-3.

Fibulin-3 (also known as EGF-containing fibulin extracellular matrix protein 1 (EFEMP1)) is a secreted extracellular matrix glycoprotein, encoded by the EFEMP1 gene that belongs to the eight-membered fibulin protein family. It has emerged as a functionally unique member of this family, with a diverse array of pathophysiological associations predominantly centered on its role as a modulator of extracellular matrix (ECM) biology. Fibulin-3 is widely expressed in the human body, especially in elastic-fibre-rich tissues and ocular structures, and interacts with enzymatic ECM regulators, including tissue inhibitor of metalloproteinase-3 (TIMP-3). A point mutation in EFEMP1 causes an inherited early-onset form of macular degeneration called Malattia Leventinese/Doyne honeycomb retinal dystrophy (ML/DHRD). EFEMP1 genetic variants have also been associated in genome-wide association studies with numerous complex inherited phenotypes, both physiological (namely, developmental anthropometric traits) and pathological (many of which involve abnormalities of connective tissue function). Furthermore, EFEMP1 expression changes are implicated in the progression of numerous types of cancer, an area in which fibulin-3 has putative significance as a therapeutic target. Here we discuss the potential mechanistic roles of fibulin-3 in these pathologies and highlight how it may contribute to the development, structural integrity, and emergent functionality of the ECM and connective tissues across a range of anatomical locations. Its myriad of aetiological roles positions fibulin-3 as a molecule of interest across numerous research fields and may inform our future understanding and therapeutic approach to many human diseases in clinical settings.

A study of optic nerve head drusen in 38 pseudoxanthoma elasticum (PXE) patients (64 eyes). Location of optic nerve head drusen in PXE.

PURPOSE: To investigate the prevalence and location of optic nerve head drusen and their potential association with other PXE-related ophthalmic abnormalities. MATERIALS AND METHODS: Thirty-eight of the 155 patients (57 male and 98 female aged 49±17 years) included in this retrospective study had optic nerve head drusen. All of the patients underwent a comprehensive ophthalmic examination, including color images using red-free, blue and red filters, autofluorescence imaging and late-phase ICG frames. Comparative analysis of both groups (optic nerve head drusen or not) was conducted using R statistical software. RESULTS: The prevalence of optic nerve head drusen in our cohort was 24.5%. In this study, no evidence of a significant link between optic nerve head drusen and other fundus abnormalities was detected. They were more commonly located in the nasal sector than in the temporal sector of the optic disc (P<0.001). They were more frequently situated superonasally than inferonasally (P<0.004), superotemporally (P<0.001) or inferotemporally (P<0.03). No central visual field defect was observed in OND+ patients who were unaffected by macular disorders. DISCUSSION: We hypothesized this predominantly nasal primary location may result from greater sensitivity in the nasal optic nerve fibers which follow a much more angular path once they arrive in the scleral canal, accounting for accumulation of axoplasmic debris. CONCLUSION: In PXE, optic nerve head drusen are mostly located in the superonasal quadrant, causing progressive optic nerve invasion but probably no central visual field defects.

Doyne honeycomb retinal dystrophy/malattia leventinese induced by EFEMP1 mutation in a Chinese family.

BACKGROUND: Doyne honeycomb retinal dystrophy (DHRD)/malattia leventinese (ML) is a rare allelic condition with massive drusen in the posterior fundus caused by EFEMP1 gene mutation. Patients showed decreased vision when the lesion affected the macular area. At present, the treatment efficiency is not satisfactory. CASE PRESENTATION: In this study, we presented a family with DHRD/ML disease and analyzed the pathological and genetic information. A 28-year-old female patient presented to our department due to impaired visual acuity for 10 years especially in the right eye with deterioration for 5 months. Gene sequencing was performed by MyGenostics (Peking, China). Gene sequencing results revealed heterozygous mutations in EFEMP1 gene, which were consistent with the DHRD/ ML. Single heterozygous mutation (c.1033C > T) was observed in each of the three blood samples. This missense mutation triggered p.R345W. CONCLUSIONS: DHRD/ML is a rare disease associated with EFEMP1 gene mutation. Up to now, we are not sure whether these lesions are associated with the onset of DHRD/ML. In future, we hope to find out the exact relationship between them.

Co-inheritance of the membrane frizzled-related protein ocular phenotype and glycogen storage disease type Ib.

AIM: To report co-occurrence of two rare recessive conditions, the membrane frizzled-related protein (MFRP)-related ocular phenotype and glycogen storage disease type 1b (GSD-1b), in three siblings in an Omani family. BACKGROUND: Biallelic mutations in the MFRP gene (chromosome 11q23) result in a distinct ocular phenotype characterized by retinitis pigmentosa, foveoschisis, optic nerve head drusen, and posterior microphthalmos. GSD-1b is an autosomal-recessive disorder caused by mutations in SLC37A4 gene located in the same chromosomal region. METHODS: An Omani family with three siblings diagnosed with GSD-1b presented with ocular manifestations of progressive visual impairment and diminution of night vision. All siblings underwent a standard ophthalmic and clinical genetic evaluation. Full sequencing of the MFRP and SLC37A4 genes and haplotype analysis was carried out. RESULTS: The three children (2F:1M) aged 13, 17, and 18 years were born to consanguineous parents. Their best-corrected visual acuity ranged from 20/60 to 20/15. Ophthalmic exam revealed bilateral optic disc drusen, foveoschisis, and pigmentary retinopathy, hyperopia of +12 to +15.5 diopters, and decreased axial length (15.8-16.39 mm) in all affected siblings. Full-field electroretinography showed rod-cone dysfunction. Sequence analysis revealed two novel variants in a homozygous state in the SLC37A4 and MFRP genes in all the affected patients. CONCLUSIONS: We report the MFRP-related ocular phenotype in three siblings with GSD-1b. Molecular genetic studies identified novel mutations in the MFRP and SLC37A4 genes. Co-inheritance of a haplotype harboring mutations in both loci on chromosome 11q23 resulted in co-occurrence of the MFRP-related ocular phenotype and GSD-1b. This has not been reported previously.

[Muscular Dystrophies Involving the Retinal Function]. / Netzhautbeteiligung bei Muskeldystrophien.

Muscular dystrophies are rare disorders, with an incidence of approx. 20 in 100 000. Some dystrophies also affect retinal or optic nerve function. In such cases, the ophthalmological findings may be critical for differential diagnosis or patient counseling. For example in Duchenne muscular dystrophy, where the alteration in retinal function seems to reflect cerebral involvement. Other important forms are mitochondrial and metabolic disorders, such as the Kearns-Sayre syndrome and the Refsum syndrome. Molecular genetic analysis has become a major tool for differential diagnosis, but may be complex and demanding. This article gives an overview of major muscular dystrophies involving retinal function and their genetic origin, in order to guide differential diagnosis.

[Optic Disk Drusen: Historical and Up-To-Date Aspects]. / Drusenpapille - ein Überblick über medizinhistorische und aktuelle Aspekte.

Optic disc drusen are an important differential diagnosis in the diagnostic evaluation of a prominent optic nerve head. Drusen of the optic disc occur in 0.34 to 2.4 % of human individuals and manifest themselves bilaterally in three of four cases. Drusen are found six times more often within histological sections than on funduscopic examination. It is known that optic disc drusen can occur in familial clusters without any other pathological ophthalmic findings. They can also be associated with retinitis pigmentosa, or with the Joubert or Alagille syndromes. Non-invasive diagnostic tools include fundus-autofluorescence (AF), optical coherence tomography (OCT) and ultrasound. Drusen of the optic nerve head are asymptomatic in most cases, though transient ischemia can lead to transient visual impairment. In particular, superficial drusen can lead to profound visual field defects in adulthood. Regular ophthalmological follow-up examinations with tonometry and perimetry are recommended for the early detection of visual field defects. Radial optic neurotomy (RON) seems to be a therapeutic option in patients with acute deterioration of the visual field.

Novel membrane frizzled-related protein gene mutation as cause of posterior microphthalmia resulting in high hyperopia with macular folds.

PURPOSE: We present a genetic and clinical analysis of two sisters, 3 and 4 years of age, with nanophthalmos and macular folds. METHODS: Ophthalmological examination, general paediatric examination and molecular genetic analysis of the MFRP gene were performed in both affected siblings. RESULTS: Clinical analysis showed high hyperopia (+11 D and +12 D), short axial lengths (15 mm) and the presence of macular folds and optic nerve head drusen. Autofluorescence of the retina was generally normal with subtle macular abnormalities. Sequence analysis showed compound heterozygosity for severe MFRP mutations in both sisters: a previously reported p.Asn167fs (c.498dupC) and a novel stop codon mutation p.Gln91X (c.271C>T). CONCLUSION: These are the youngest nanophthalmos patients in the literature identified with severe loss of MFRP function, showing already the known structural abnormalities for this disease. Adult patients affected by homozygous or compound heterozygous MFRP mutations generally show signs of retinal dystrophy, with ERG disturbances and RPE abnormalities on autofluorescence imaging. ERG examination could not be performed in these children, but extensive RPE abnormalities were not seen at this young age.

Membrane frizzled-related protein gene-related ophthalmological syndrome: 30-month follow-up of a sporadic case and review of genotype-phenotype correlation in the literature.

PURPOSE: To report a new sporadic case of membrane frizzled-related protein gene (MFRP)-related syndrome with a 30-month follow-up, and to review the literature for genotype-phenotype correlation in MFRP mutations. METHODS: A complete ophthalmological evaluation was performed at presentation and 30 months later, including best-corrected visual acuity test, slit lamp examination, fundoscopy, kinetic perimetry, electroretinography, fundus imaging (color, red-free, and autofluorescence), and morphologic-biometric analysis of the eye structures with an optical biometer, anterior-segment optical coherence tomography, retinal optical coherence tomography, and a confocal scanning laser for optic nerve head study. Polymerase chain reaction amplification of DNA obtained from peripheral blood lymphocytes and nucleotide sequencing of the complete MFRP gene were performed. The literature on cases of posterior microphthalmos and retinitis pigmentosa associated with MFRP mutations was reviewed. RESULTS: A 33-year-old female patient presented with posterior microphthalmos, retinitis pigmentosa with patches of retinal pigmented epithelium atrophy and scarce pigment mobilization, foveoschisis, and optic nerve drusen. After 30 months, progression of rod-cone retinal degeneration was detected. One obligate carrier showed a normal eye phenotype. A homozygote mutation in the MFRP gene (c.492delC), predicting a truncated protein (P166fsX190), was identified with genetic analysis. To our knowledge, 17 cases of MFRP-related syndrome have been reported in the literature, including the patient described herein. The phenotype of the syndrome, expressivity, and age of onset varied among and within the affected families. However, all patients sharing homozygous mutation c.492delC (alternatively named c.498delC) showed a complete phenotype (including foveoschisis and optic nerve head drusen), and similar fundus characteristics. CONCLUSIONS: A new sporadic case of MFRP-related syndrome is reported. Review of the literature showed variability in the phenotype, but initial elements of genotype-phenotype correlation have been identified in patients sharing the mutation of the present case.

A novel crumbs homolog 1 mutation in a family with retinitis pigmentosa, nanophthalmos, and optic disc drusen.

PURPOSE: The purpose of this study is to identify the genetic defect in a Turkish family with autosomal recessive retinitis pigmentosa, nanophthalmos, and optic disc drusen. METHODS: Ophthalmological examinations consisted of measuring the best-corrected visual acuity and the refractive error, electroretinography, optical coherence tomography, B-mode ultrasonography, and fundus photography. The involvement of the membrane frizzled-related protein (MFRP) gene in this family was studied with direct DNA sequencing of the coding exons of MFRP and with linkage analysis with microsatellite markers. After MFRP was excluded, genome-wide homozygosity mapping was performed with 250 K single nucleotide polymorphism (SNP) microarrays. Mutation analysis of the crumbs homolog 1 (CRB1) gene was performed with direct sequencing. RESULTS: Ophthalmological evaluation of both affected individuals in the family revealed a decreased axial length (18-19 mm), retinal dystrophy, macular edema, and hyperopia of >+8.0 diopters. Sequencing of MFRP did not reveal any pathogenic changes, and microsatellite marker analysis showed that the chromosomal region did not segregate within the disease in this family. Genome-wide homozygosity mapping using single nucleotide polymorphism microarrays revealed a 28-Mb homozygous region encompassing the CRB1 gene, and direct sequencing disclosed a novel homozygous missense mutation (p.Gly833Asp) in CRB1. CONCLUSIONS: Previous studies associated mutations in the MFRP gene with the syndrome nanophthalmos-retinitis pigmentosa-foveoschisis-optic disc drusen. In this study, we demonstrated that a similar disease complex can be caused by mutations in the CRB1 gene.

Multimodal imaging of autosomal dominant drusen.

BACKGROUND: Malattia Leventinese (ML) is a dominantly inherited macular dystrophy characterized by a radial pattern of drusen in the macular area and on the nasal edge of the optic disc. This case series describes the morphological features of drusen associated with ML using multimodal imaging. HISTORY AND SIGNS: Three patients (two of the same family but only one with the ML phenotype) were analyzed by multimodal imaging including spectral domain optical coherence tomography (SD OCT) and genetic testing. In two patients multiple drusen in the macular region and around the optic nerve head were observed bilaterally. A radial pattern was only seen in one patient. These drusenoid deposits showed early hyperfluorescence in fluorescein angiography (FA) and intense staining in indocyanine green angiography similar to cuticular drusen (basal laminar drusen). The corresponding SD OCT scan revealed two types of deposits. The first, more prominent type, were focal nodular sub-retinal pigment epithelium (RPE) deposits. The second type of deposit appears to be localized on the anterior part of the RPE comparable to subretinal drusenoid deposits (SDD; reticular pseudodrusen). THERAPY AND OUTCOME: A single nucleotide variation c.1033C>T (p.R345 W) in the EFEMP1 gene was found in case 1 (classic ML), but could not be detected in case 2 and 3. So far our patients have not suffered from any visual complaints and have not developed choroidal neovascularization. They will be followed up regularly. DISCUSSION: Multimodal imaging including SD OCT provided new information about the appearance of drusen in eyes with ML/early onset drusen. In addition to the sub-RPE deposits some deposits appear above the RPE, however have different characteristic findings on FA/ICG, autofluorescence, near infrared reflectance and blue light imaging than SDD observed in patients with age-related macular degeneration. SD OCT alone might not be sufficient to characterize these type of drusen in ML.

Associations of complement factor H and smoking with early age-related macular degeneration: the ALIENOR study.

PURPOSE: To assess the associations of complement factor H (CFH) Y402H polymorphism and smoking with specific features of early AMD (type, location, and area). METHODS: The ALIENOR study is a population-based study of age-related eye diseases in 963 residents of Bordeaux (France), aged 73 years or more. AMD features were graded from nonmydriatic color retinal photographs. CFH Y402H was genotyped by using DNA extracted from blood. Statistical analyses included 796 subjects with complete data. RESULTS: CFH CC genotype was strongly associated with late neovascular AMD (OR, 6.0; 95% confidence interval [CI], 1.5-23.5) but not with late atrophic AMD (OR, 0.9; 95% CI, 0.2-4.3). Among early characteristics, it was associated with central soft drusen (within 500 µm of the fovea), whether of intermediate (63-125 µm; OR, 2.7; 95% CI, 1.5-4.8), or large (>125 µm; OR, 5.9; 95% CI, 2.2-15.7) size, but not with pericentral soft drusen (500-3000 µm from the fovea). It was also strongly associated with a large central area of soft drusen (OR, 5.7; 95% CI, 1.7-19.2). Similarly, heavy smoking (>20 pack-years) was strongly associated with central large drusen (OR, 3.9; 95% CI, 1.6-9.6) and a large central area of drusen (OR, 3.5; 95% CI, 1.2-10.0), but not with pericentral soft drusen. By contrast, both CFH CC and smoking tended to be more strongly associated with pericentral pigmentary abnormalities. CONCLUSIONS: Location of abnormalities, together with type and area, may prove useful for the identification of subjects at high risk for late AMD.

Association of variants in the LIPC and ABCA1 genes with intermediate and large drusen and advanced age-related macular degeneration.

PURPOSE: Intermediate and large drusen usually precede advanced age-related macular degeneration (AMD). There is little information about which genes influence drusen accumulation. Discovery of genetic variants associated with drusen may lead to prevention and treatments of AMD in its early stages. METHODS: A total of 3066 subjects were evaluated on the basis of ocular examinations and fundus photography and categorized as control (n = 221), intermediate drusen (n = 814), large drusen (n = 949), or advanced AMD (n = 1082). SNPs in the previously identified CFH, C2, C3, CFB, CFI, APOE, and ARMS2/HTRA1 genes/regions and the novel genes LIPC, CETP, and ABCA1 in the high-density lipoprotein (HDL) cholesterol pathway were genotyped. Associations between stage of AMD and SNPs were assessed using logistic regression. RESULTS: Controlling for age, sex, education, smoking, body mass index, and antioxidant treatment, the number of minor (T) alleles of the genes LIPC and ABCA1 were significantly associated with a reduced risk of intermediate drusen (LIPC [P trend = 0.045], ABCA1 [P = 4.4 × 10(-3)]), large drusen (LIPC [P = 0.041], ABCA1 [P = 7.7 × 10(-4)]), and advanced AMD (LIPC [P = 1.8 × 10(-3)], ABCA1 [P = 3 × 10(-4)]). After further adjustment for known genetic factors, the protective effect of the TT genotype was significant for intermediate drusen (LIPC [odds ratio (OR), 0.56; 95% confidence interval (CI), 0.33-0.94], ABCA1 [OR, 0.48; 95% CI, 0.27-0.85]), large drusen (LIPC [OR, 0.58; 95% CI, 0.34-0.98)], ABCA1 [OR, 0.41; 95% CI, 0.23-0.74)]), and advanced AMD (LIPC [OR, 0.39; 95% CI, 0.21-0.74)], ABCA1 [OR, 0.35; 95% CI, 0.17-0.71)]). CFH, C3, C2, and ARMS2/HTRA1 were associated with large drusen and advanced AMD. CONCLUSIONS: LIPC and ABCA1 are related to intermediate and large drusen, as well as advanced AMD. CFH, C3, C2, and ARMS2/HTRA1 are associated with large drusen and advanced AMD. Genes may have varying effects on different stages of AMD.

The phenotype of Severe Early Childhood Onset Retinal Dystrophy (SECORD) from mutation of RPE65 and differentiation from Leber congenital amaurosis.

PURPOSE: To describe in detail the characteristic clinical phenotype and electrophysiological features of Severe Early Childhood Onset Retinal Dystrophy (SECORD) caused by mutation of RPE65. METHODS: Ophthalmological examination, color fundus photography, visual field testing, detailed electrophysiological assessment, and screening of RPE65 were undertaken in five subjects. Selected patients also had spectral domain optical coherence tomography. RESULTS: All five patients had life-long, extremely poor night vision. Variable degrees of nystagmus were present; three cases lacked nystagmus at the time of assessment. Bilateral disc drusen were evident in three subjects. While case 1 had an undetectable electroretinogram and features supporting a diagnosis of Leber congential amaurosis (LCA) as an infant, her level of acuity and function into the second decade of life was more consistent with SECORD. In two cases, both vision and electrophysiological responses were seen to improve into the second decade of life. The objective demonstration of improved retinal function over time, with electrophysiological testing, has not been previously reported. Cases 4 and 5 had evidence of fine white retinal dots. The authors propose that these represent abnormal accumulations of retinyl esters, as has been demonstrated in animal models, and has also been observed as lipid droplets within the retinal pigment epithelium (RPE). These white dots were seen to fade with time in the patients and were replaced by RPE changes. CONCLUSIONS: The identification of patients with mutations in RPE65 has attained greater significance now that gene replacement trials have begun. The features presented in this article assist in the recognition of this form of LCA/SECORD.

[Retinitis pigmentosa--clinical and genetic aspects with low vision]. / Retinitis pigmentosa--clinica, genetica si low-vision.

PURPOSE: Clinical and genetic study of a case of retinitis pigmentosa following the vision and the quality of life in this disease. METHOD: This paper presents a female periodically reevaluated in our clinic from the first diagnosis of retinitis pigmentosa which was established ten years ago, with many relatives with the diagnosis of retinitis pigmentosa, has also high hyperopia and optic disc drusen. A particular aspect--she is student at English Faculty and she want to become professor in a school for children with low vision. Clinical evaluation included complete ophthalmic and general examination, family history and also some additional lab and imaging study, In genetic evaluation of this case were used the basic rules of genetics to diagnose the genetic form of retinitis pigmentosa in order to offer a correct genetic counseling. CONCLUSIONS: Retinitis pigmentosa needs a broad clinical evaluation and a careful socio-professional rehabilitation of these low-vision patients.