Disease-specific variant interpretation highlighted the genetic findings in 2325 Japanese patients with retinitis pigmentosa and allied diseases

BACKGROUND

As gene-specific therapy for inherited retinal dystrophy (IRD) advances, unified variant interpretation across institutes is becoming increasingly important. This study aims to update the genetic findings of 86 retinitis pigmentosa (RP)-related genes in a large number of Japanese patients with RP by applying the standardised variant interpretation guidelines for Japanese patients with IRD (J-IRD-VI guidelines) built upon the American College of Medical Genetics and Genomics and the Association for Molecular Pathology rules, and assess the contribution of these genes in RP-allied diseases.

METHODS

We assessed 2325 probands with RP (n=2155, including n=1204 sequenced previously with the same sequencing panel) and allied diseases (n=170, newly analysed), including Usher syndrome, Leber congenital amaurosis and cone-rod dystrophy (CRD). Target sequencing using a panel of 86 genes was performed. The variants were interpreted according to the J-IRD-VI guidelines.

RESULTS

A total of 3564 variants were detected, of which 524 variants were interpreted as pathogenic or likely pathogenic. Among these 524 variants, 280 (53.4%) had been either undetected or interpreted as variants of unknown significance or benign variants in our earlier study of 1204 patients with RP. This led to a genetic diagnostic rate in 38.6% of patients with RP, with EYS accounting for 46.7% of the genetically solved patients, showing a 9% increase in diagnostic rate from our earlier study. The genetic diagnostic rate for patients with CRD was 28.2%, with RP-related genes significantly contributing over other allied diseases.

CONCLUSION

A large-scale genetic analysis using the J-IRD-VI guidelines highlighted the population-specific genetic findings for Japanese patients with IRD; these findings serve as a foundation for the clinical application of gene-specific therapies.

Genetic and Clinical Features of ABCA4-Associated Retinopathy in a Japanese Nationwide Cohort

PURPOSE

To clarify the genetic and clinical features of Japanese patients with ABCA4-associated retinopathy.

DESIGN

Retrospective, multicenter cohort study.

METHODS

Patients with retinal degeneration and biallelic ABCA4 variants were recruited from 13 different hospitals. Whole exome sequencing analysis was used for genetic testing. Comprehensive ophthalmic examinations were performed on matched patients. The primary outcome measure was identifying multimodal retinal imaging findings associated with disease progression.

RESULTS

This study included 63 patients: 19 with missense/missense, 23 with missense/truncation, and 21 with truncation/truncation genotypes. In total, 62 variants were identified, including 29 novel variants. Six patients had a mild phenotype characterized by foveal-sparing or preserved foveal structure, including 4 with missense/missense and 2 with missense/truncation genotypes. The p.Arg212His variant was the most frequent in patients with mild phenotypes (4/12 alleles). Clinical findings showed a disease duration-dependent worsening of the phenotypic stage. Patients with the truncation/truncation genotype exhibited rapid retinal degeneration within a few years and definite fundus autofluorescence imaging patterns, including hyper autofluorescence at the macula and few or no flecks.

CONCLUSIONS

Our results indicate that missense/missense or missense/truncation genotypes, including the p.Arg212His variant, are associated with a relatively mild phenotype. In contrast, the truncation/truncation genotype causes rapid and severe retinal degeneration in Japanese patients with ABCA4-associated retinopathy. These data are vital in predicting patient prognosis, guiding genetic counseling, and stratifying patients for future clinical trials.

Intraocular pressure changes at different gaze positions after superior rectus muscle-lateral rectus muscle loop myopexy in highly myopic strabismus

PURPOSE

To evaluate changes in intraocular pressure (IOP) at different gaze positions before and after superior rectus muscle-lateral rectus muscle (SR-LR) loop myopexy in highly myopic strabismus (HMS).

STUDY DESIGN

Nonrandomized clinical, prospective, interventional trial.

METHODS

Fourteen patients with HMS (18 eyes) who underwent SR-LR loop myopexy were divided into 3 groups: < 100 prism diopters (PD) (mild esotropia [ET] group), > 100 PD (large ET group), and > 100 PD, and simultaneous recession of the medial rectus (MR) muscle was performed (large ET + MR group). Intraocular pressure was measured preoperatively and postoperatively at the primary, abduction, and adduction positions in each group.

RESULTS

Intraocular pressure did not change after surgery in the mild ET group. Intraocular pressure significantly decreased in the abduction position (from 20.0 ± 2.1 to 16.0 ± 1.9 mmHg, P = 0.043) in the large ET group and in the abduction (from 22.2 ± 5.9 to 15.6 ± 4.3 mmHg, P = 0.048) and primary positions (from 15.8 ± 5.0 to 10.2 ± 2.8 mmHg, P = 0.043) in the large ET + MR group. The preoperative significant differences in IOP between the abduction and adduction positions in the large ET group (7.4 ± 3.4 mmHg) and the large ET + MR group (10.0 ± 5.5 mmHg) disappeared postoperatively (3.2 ± 2.8 mmHg and 3.6 ± 1.7 mmHg, respectively). The differences in IOP between abduction and adduction were similar in all the groups.

CONCLUSION

SR-LR loop myopexy decreased IOP in patients with HMS in the abduction and primary positions.

Recovery of stereoacuity after Yokoyama procedure in patients with highly myopic strabismus with good vision

Purpose

To report stereopsis after bilateral Yokoyama procedure in patients with highly myopic strabismus and good visual acuity.

Observations

Five patients aged between 34 and 81 years with best-corrected visual acuity of 20/25 or better were operated on. The preoperative strabismus angle ranged from esotropia of 35-113 prism diopters (PD) at distance and esotropia of 40-113 PD at near. One patient had left hypotropia of 4 PD and excyclotorsion of 15°, and the other had left hypotropia of 10 PD. Their axial lengths were 27.65-33.07 mm, and the posterior globe dislocation angles were between 123 and 148° on coronal magnetic resonance imaging (MRI). Limitations of abduction were between -1 and -2. All patients complained of diplopia, and none of them showed stereopsis. The Yokoyama procedure was performed on both eyes. Postoperative alternate cover testing showed from esotropia of 2 PD to exophoria of 8 PD at distance and from exotropia of 12 PD to esophoria of 10 PD at near.Three patients recovered stereopsis of 100, 50, and 140 sec, respectively. Two cases required unilateral inferior rectus muscle recessions, and their postoperative stereopsis was 25 and 50 sec.

Conclusions and Importance

The Yokoyama procedure is effective not only in cases of heavy eye syndrome but also in cases of myopic esotropia associated with a globe dislocation angle of 120° or with little abduction restriction. If visual acuity is good, stereopsis may be restored with improvement in eye deviation.

A case of siblings with juvenile retinitis pigmentosa associated with NEK1 gene variants

BACKGROUND

Axial spondylometaphyseal dysplasia(axial SMD) is associated with early-onset retinal dystrophy and various skeletal dysplasias of varying severity. NEK1 is the causative gene for short rib polydactyly syndrome and axial SMD. Here, we report a case of siblings with juvenile retinitis pigmentosa (RP) and NEK1 variants not associated with systemic disorders.

MATERIALS AND METHODS

The patients were a 7-year-old-girl and a 9-year-old boy with RP, who were followed for 9 years. Whole exome sequencing (WES) was performed on the siblings and their parents, who were not consanguineous.

RESULTS

The corrected visual acuity of the girl and the boy at first visit was binocular 20/63 and 20/100 OD and 20/63 OS, respectively. The siblings had narrowing of retinal blood vessels and retinal pigment epithelium atrophy in the fundus and showed an extinguished pattern in electroretinogram. On optical coherence tomography, there was a mottled ellipsoid band with progressive loss in the outer macular, the edges of which corresponded to the ring of hyperautofluorescence on fundus autofluorescence imaging. The siblings showed progressive visual field constriction. Radiological examination did not reveal any skeletal abnormalities. We identified two rare heterozygous NEK1 variants in the patients: c.240 G>A; p.(M80I) and c.634_639dup;p.(V212_L213dup). Heterozygous variants were recognized in the father and mother, respectively. According to the guidelines of the American College of Medical Genetics and Genomics, both variants were classified as likely pathogenic.

CONCLUSION

This is the first report of RP patients with NEK1 variants not associated with skeletal abnormalities.

The Structural Abnormalities Are Deeply Involved in the Cause of RPGRIP1-Related Retinal Dystrophy in Japanese Patients

Leber congenital amaurosis (LCA) is the most severe form of inherited retinal dystrophy. RPGRIP1-related LCA accounts for 5-6% of LCA. We performed whole-exome sequencing and whole-genome sequencing (WGS) on 29 patients with clinically suspected LCA and examined ophthalmic findings in patients with biallelic pathogenic variants of RPGRIP1. In addition to five previously reported cases, we identified five cases from four families with compound heterozygous RPGRIP1 variants using WGS. Five patients had null variants comprising frameshift variants, an Alu insertion, and microdeletions. A previously reported 1339 bp deletion involving exon 18 was found in four cases, and the deletion was relatively prevalent in the Japanese population (allele frequency: 0.002). Microdeletions involving exon 1 were detected in four cases. In patients with RPGRIP1 variants, visual acuity remained low, ranging from light perception to 0.2, and showed no correlation with age. In optical coherence tomography images, the ellipsoid zone (EZ) length decreased with age in all but one case of unimpaired EZ. The retinal structure was relatively preserved in all cases; however, there were cases with great differences in visual function compared to their siblings and a 56-year-old patient who still had a faint EZ line. Structural abnormalities may be important genetic causes of RPGRIP1-related retinal dystrophy in Japanese patients, and WGS was useful for detecting them.

Steroid-induced ocular hypertensive response in pediatric patients with acute lymphoblastic leukemia

PURPOSE

To report the characteristics of the steroid-induced ocular hypertensive response in pediatric patients with acute lymphoblastic leukemia (ALL) treated with prednisolone (PSL) during induction therapy and with dexamethasone (DEX) during reinduction therapy.

STUDY DESIGN

Retrospective.

PATIENTS AND METHODS

This study included pediatric patients diagnosed with B-cell precursor ALL and treated with systemic corticosteroids sometime during the period from 2016 to 2018 at Shizuoka Children's Hospital. Data were extracted from the hematology/oncology records related to the type, dose, and duration of systemic corticosteroids as well as to the ophthalmologic examination findings, intraocular pressure (IOP) data, symptoms of high IOP, and antiglaucoma medications obtained during corticosteroid administration. The maximal IOPs of the PSL and DEX groups were compared.

RESULTS

Twenty-eight patients (18 boys and 10 girls; mean age 5.5 years) were treated with systemic corticosteroids. Twelve of the 22 courses of PSL and 33 of the 44 courses of DEX were found to be associated with high IOP. The maximal IOP was higher with the use of DEX than with the use of PSL, including in those who received prophylactic therapy (PSL 25.2 mmHg, DEX 33.6 mmHg; P = 0.02). Antiglaucoma medication was given to 21 patients; 6 patients had symptoms of ocular hypertension. The maximal IOPs were 52.8 mmHg and 70.8 mmHg in the PSL and DEX groups, respectively. Both groups of patients reported severe headache.

CONCLUSION

Increased IOP was frequently observed during systemic corticosteroid therapy in pediatric patients with ALL. Although most patients were asymptomatic, they occasionally presented with severe systemic symptoms. Regular ophthalmologic examinations should be included in the treatment guidelines for ALL.

A pediatric case of congenital stromal corneal dystrophy caused by the novel variant c.953del of the DCN gene

We report a 1-year-old girl with congenital stromal corneal dystrophy confirmed by genetic analysis. The ocular phenotype included diffuse opacity over the corneal stroma bilaterally. We performed a genetic analysis to provide counseling to the parents regarding the recurrence rate. Whole exome sequencing was performed on her and her parents, and a novel de novo variant, NM_001920.5: c.953del, p.(Asn318Thrfs*10), in the DCN gene was identified in the patient.

Genetic characterization of 1210 Japanese pedigrees with inherited retinal diseases by whole-exome sequencing

Inherited retinal diseases (IRDs) comprise a phenotypically and genetically heterogeneous group of ocular disorders that cause visual loss via progressive retinal degeneration. Here, we report the genetic characterization of 1210 IRD pedigrees enrolled through the Japan Eye Genetic Consortium and analyzed by whole exome sequencing. The most common phenotype was retinitis pigmentosa (RP, 43%), followed by macular dystrophy/cone- or cone-rod dystrophy (MD/CORD, 13%). In total, 67 causal genes were identified in 37% (448/1210) of the pedigrees. The first and second most frequently mutated genes were EYS and RP1, associated primarily with autosomal recessive (ar) RP, and RP and arMD/CORD, respectively. Examinations of variant frequency in total and by phenotype showed high accountability of a frequent EYS missense variant (c.2528G>A). In addition to the two known EYS founder mutations (c.4957dupA and c.8805C>G) of arRP, we observed a frequent RP1 variant (c.5797C>T) in patients with arMD/CORD.

Intraocular pressure at different gaze positions in patients with highly myopic strabismus

PURPOSE

To evaluate intraocular pressure (IOP) at different gaze positions in patients with highly myopic strabismus (HMS).

STUDY DESIGN

Nonrandomized, prospective, observational study.

METHODS

This study included 18 eyes of 14 patients with HMS and 51 eyes of 51 age-matched controls without strabismus; these were further divided into two groups based on refractive errors: > -6.00 diopter (D) (n = 22 eyes) and ≤ -6.00 D (n = 29 eyes). IOP was measured in primary and side gazes and compared within and among groups. The relationships between IOPs and axial length, angle of globe dislocation measured on magnetic resonance imaging, strabismus angle, and degree of abduction deficit were studied.

RESULTS

The HMS group showed higher IOP in abduction (19.3 ± 4.9 mmHg) than in the primary (12.5 ± 4.3 mmHg) and adducting positions (13.0 ± 3.3 mmHg), (p < 0.001). The IOP in the adducting position in the HMS group (13.0 ± 3.3 mmHg) was lower than in the control groups both with (17.6 ± 3.5 mmHg) and without (16.9 ± 4.1 mmHg) high myopia, ; (p < 0.001 and = 0.003). The difference in IOP between abduction and adduction was significantly larger in the HMS group (6.4 ± 4.6 mmHg) compared to others (p < 0.001) and positively correlated with the strabismus angle and the angle of globe dislocation and negatively with abduction deficit.

CONCLUSION

The IOP of patients with HMS changes dramatically on side gazes, therefore, care should be taken while measuring IOP.

Medial Rectus Muscle Resection Versus Plication: A Comparison of Conjunctival-Scleral Thickness Measured by AS-OCT

PURPOSE

To compare conjunctival-scleral thickness measured with anterior segment optical coherence tomography before and after medial rectus muscle resection and plication for exotropia.

METHODS

In this prospective observational study, patients with exotropia aged 5 years and older who underwent medial rectus muscle resection or plication through limbal incision of the conjunctiva between April 2016 and June 2018 were enrolled. Conjunctivalscleral thickness was measured with anterior segment optical coherence tomography before and 3 and 6 months after surgery at 1.5 mm (limbus), 4 mm (insertion), and 5.5 mm (tendon) posterior to the scleral spur. One examiner made measurements twice blinded for the initial data. Conjunctival-scleral thickness was compared between groups using the Mann-Whitney U test.

RESULTS

Twenty participants were divided into two groups: resection (n = 11) and plication (n = 9). The respective conjunctival-scleral thicknesses before and 3 and 6 months after surgery in the resection group were as follows: 0.76, 0.90, and 0.86 mm at the limbus; 0.86, 1.18, and 1.12 mm at the insertion; and 1.04, 1.41, and 1.33 mm at the tendon. Corresponding values in the plication group were as follows: 0.74, 0.87, and 0.81 mm at the limbus; 0.84, 1.16, and 1.08 mm at the insertion; and 1.00, 1.39, and 1.27 mm at the tendon. No between-group differences were observed at any location or time.

CONCLUSIONS

No differences in conjunctival-scleral thickness were observed between the resection and plication groups before surgery or at 3 months and 6 months postoperatively. [J Pediatr Ophthalmol Strabismus. 2022;59(4):274-278.].

Likely pathogenic structural variants in genetically unsolved patients with retinitis pigmentosa revealed by long-read sequencing

Despite the successful identification of causative genes and genetic variants of retinitis pigmentosa (RP), many patients have not been molecularly diagnosed. Our recent study using targeted short-read sequencing showed that the proportion of carriers of pathogenic variants in EYS, the cause of autosomal recessive RP, was unexpectedly high in Japanese patients with unsolved RP. This result suggested that causative genetic variants, which are difficult to detect by short-read sequencing, exist in such patients. Using long-read sequencing technology (Oxford Nanopore), we analysed the whole genomes of 15 patients with RP with one heterozygous pathogenic variant in EYS detected in our previous study along with structural variants (SVs) in EYS and another 88 RP-associated genes. Two large exon-overlapping deletions involving six exons were identified in EYS in two patients with unsolved RP. An analysis of an independent patient set (n=1189) suggested that these two deletions are not founder mutations. Our results suggest that searching for SVs by long-read sequencing in genetically unsolved cases benefits the molecular diagnosis of RP.

Exophthalmos associated with chronic progressive external ophthalmoplegia

PURPOSE

Chronic progressive external ophthalmoplegia (CPEO) is a mitochondrial disease characterized by slowly progressive ptosis and limitations in ocular motility. Although exophthalmos is not considered to be a common feature of CPEO, this study focused on the incidence of exophthalmos in patients with CPEO.

STUDY DESIGN

Retrospective observational case series METHODS: We reviewed the clinical charts of patients who received a diagnosis of CPEO sometime during the period between January 2010 and December 2018. CPEO was diagnosed on the basis of detection of a deletion of mitochondrial DNA (mtDNA) from saliva, buccal mucosa, or extraocular muscle specimens obtained during strabismus surgery. Horizontal MRI/CT images or Hertel ophthalmometry was used in determining exophthalmos.

RESULTS

Seven patients (4 males) were identified. The mean age at diagnosis was 32.6 years (range 13-53 years). mtDNA deletion mutations were detected in the buccal mucous membrane DNA in 5 patients and in the saliva and extraocular muscle DNA in 2 patients. MRI/CT was recorded in 6 patients, four of whom showed exophthalmos (cases 1-4), and case 5 was determined as exophthalmos on the basis of a Hertel ophthalmometer reading. Exophthalmos was bilateral in 4 of the patients (cases 1, 2, 4, and 5) and unilateral in 1 patient (case 3). Exophthalmos was the chief concern of 2 of the patients; however, it was not clinically significant in the other patients.

CONCLUSIONS

Although exophthalmos may not be recognized by either the patient or the clinician, it may be one of the common features of CPEO. A large multiethnic study should be performed.

De novo heterozygous variants in KIF5B cause kyphomelic dysplasia

Kyphomelic dysplasia is a heterogeneous group of skeletal dysplasias characterized by severe bowing of the limbs associated with other variable findings, such as narrow thorax and abnormal facies. We searched for the genetic etiology of this disorder. Four individuals diagnosed with kyphomelic dysplasia were enrolled. We performed whole-exome sequencing and evaluated the pathogenicity of the identified variants. All individuals had de novo heterozygous variants in KIF5B encoding kinesin-1 heavy chain: two with c.272A>G:p.(Lys91Arg), one with c.584C>A:p.(Thr195Lys), and the other with c.701G>T:p.(Gly234Val). All variants involved conserved amino acids in or close to the ATPase activity-related motifs in the catalytic motor domain of the KIF5B protein. All individuals had sharp angulation of the femora and humeri, distinctive facial features, and neonatal respiratory distress. Short stature was observed in three individuals. Three developed postnatal osteoporosis with subsequent fractures, two showed brachycephaly, and two were diagnosed with optic atrophy. Our findings suggest that heterozygous KIF5B deleterious variants cause a specific form of kyphomelic dysplasia. Furthermore, alterations in kinesins cause various symptoms known as kinesinopathies, and our findings also extend the phenotypic spectrum of kinesinopathies. This article is protected by copyright. All rights reserved.

Maternal Uniparental Isodisomy of Chromosome 4 and 8 in Patients with Retinal Dystrophy: SRD5A3-Congenital Disorders of Glycosylation and RP1-Related Retinitis Pigmentosa

Purpose: Uniparental disomy (UPD) is a rare chromosomal abnormality. We performed whole-exosome sequencing (WES) in cases of early-onset retinal dystrophy and identified two cases likely caused by UPD. Herein, we report these two cases and attempt to clarify the clinical picture of retinal dystrophies caused by UPD. Methods: WES analysis was performed for two patients and their parents, who were not consanguineous. Functional analysis was performed in cases suspected of congenital disorders of glycosylation (CDG). We obtained clinical case data and reviewed the literature. Results: In case 1, a novel c.57G>C, p.(Trp19Cys) variant in SRD5A3 was detected homozygously. Genetic analysis suggested a maternal UPD on chromosome 4, and functional analysis confirmed CDG. Clinical findings showed early-onset retinal dystrophy, intellectual disability, and epilepsy. In case 2, an Alu insertion (c.4052_4053ins328, p.[Tyr1352Alafs]) in RP1 was detected homozygously. Maternal UPD on chromosome 8 was suspected. The clinical picture was consistent with RP1-related retinitis pigmentosa. Although the clinical features of retinal dystrophy by UPD may vary, most cases present with childhood onset. Conclusions: There have been limited reports of retinal dystrophy caused by UPD, suggesting that it is rare. Genetic counseling may be encouraged in pediatric cases of retinal dystrophy.

Identification of susceptibility loci for light-induced visual impairment in rats

Bright light exposure in animals results in the selective degeneration of the outer retina, known as "retinal photic injury" (RPI). The susceptibility to RPI differs among rat strains. WKY rats display susceptibility to RPI with extensive retinal degeneration observed in the sagittal eye specimen, whereas LEW strain rats are resistant to it, showing only slight or no degeneration. In the present study, we first established an ethological screening method using the Morris water maze to discern differential susceptibility among the living rats. WKY and LEW were crossed to produce the first filial generation (F₁) offspring. Maze-trained individuals were exposed to bright, white light. The screening test results demonstrated that the susceptibility to light-induced visual impairment in rats is a dominant Mendelian susceptibility trait, as F₁ rats were susceptible to visual impairment like WKY rats. Therefore, F₁ rats were backcrossed with recessive LEW to produce the first backcross offspring (BC₁). Subsequent recurrent backcrossing while selecting for the susceptibility, indicated a segregation ratio of ca. 24% in BC₁ and BC₂ generations, indicating the involvement of two or more genes in the susceptibility. Further, microsatellite analysis of BC₁-to-BC₄ individuals using microsatellite markers mapped two susceptibility loci on chromosome segments 5q36 and 19q11-q12, named RPI susceptibility (Rpi)1 and Rpi2, respectively. This study provides an insight into mechanisms underlying differential susceptibility, which could help decipher the mechanism underlying the onset/progression of human age-related macular degeneration.

Retinal Features of Family Members With Familial Exudative Vitreoretinopathy Caused By Mutations in KIF11 Gene

Purpose

To determine the clinical characteristics of patients and family members with familial exudative vitreoretinopathy (FEVR) caused by mutations in the KIF11 gene.

Methods

Twenty-one patients from 10 FEVR families with mutations in the KIF11 gene were studied. The retinal and systemic features were examined. The genetic analyses performed included Sanger sequencing of the KIF11 gene, whole exome sequencing, as well as array comparative genomic hybridization (CGH) analysis and multiple ligation probe assay (MLPA).

Results

Sequence analysis revealed seven different KIF11 mutations. Array CGH with MLPA revealed two different exon deletions. All probands had advanced FEVR with retinal detachments (RDs) and microcephaly with or without developmental disabilities. Patients with bilateral RDs were more frequently associated with developmental disabilities (P = 0.023). Multimodal imaging of the family members revealed that six of nine patients without RDs (66%) had varying degrees of chorioretinopathy. The retinal folds in FEVR patients were associated with severe retinal avascularization. However, funduscopic changes in the peripheral retina were unremarkable in family members without RDs. A score representing the peripheral vascular anomalies determined from the fluorescein angiograms was lower than that of control eyes of patients with mutations of the Wnt signaling genes (P = 0.0029).

Conclusions

The probands with KIF11 mutations were associated with severe ocular and systemic pathologies, whereas affected family members showed highly variable clinical manifestations. Peripheral vascular anomalies can often be unremarkable in eyes without RDs.

Translational Relevance

These findings highlight more diverse mechanisms that underlie the pathological changes in patients with FEVR.

Genotype-Phenotype Correlations in RP1-Associated Retinal Dystrophies: A Multi-Center Cohort Study in JAPAN

Background: Little is known about genotype–phenotype correlations of RP1-associated retinal dystrophies in the Japanese population. We aimed to investigate the genetic spectrum of RP1 variants and provide a detailed description of the clinical findings in Japanese patients. Methods: In total, 607 patients with inherited retinal diseases were examined using whole-exome/whole-genome sequencing (WES/WGS). PCR-based screening for an Alu element insertion (c.4052_4053ins328/p.Tyr1352AlafsTer9) was performed in 18 patients with autosomal-recessive (AR)-retinitis pigmentosa (RP) or AR-cone dystrophy (COD)/cone-rod dystrophy (CORD), including seven patients with heterozygous RP1 variants identified by WES/WGS analysis, and 11 early onset AR-RP patients, in whom no pathogenic variant was identified. We clinically examined 25 patients (23 families) with pathogenic RP1 variants, including five patients (five families) with autosomal-dominant (AD)-RP, 13 patients (11 families) with AR-RP, and seven patients (seven families) with AR-COD/CORD. Results: We identified 18 pathogenic RP1 variants, including seven novel variants. Interestingly, the Alu element insertion was the most frequent variant (32.0%, 16/50 alleles). The clinical findings revealed that the age at onset and disease progression occurred significantly earlier and faster in AR-RP patients compared to AD-RP or AR-COD/CORD patients. Conclusions: Our results suggest a genotype–phenotype correlation between variant types/locations and phenotypes (AD-RP, AR-RP, and AR-COD/CORD), and the Alu element insertion was the most major variant in Japanese patients with RP1-associated retinal dystrophies.

Regional differences in genes and variants causing retinitis pigmentosa in Japan

PURPOSE

To investigate the regional differences in the genes and variants causing retinitis pigmentosa (RP) in Japan STUDY DESIGN: Retrospective multicenter study METHODS: In total, 1204 probands of each pedigree clinically diagnosed with nonsyndromic RP were enrolled from 5 Japanese facilities. The regions were divided into the Tohoku region, the Kanto and Chubu regions, and the Kyushu region according to the location of the hospitals where the participants were enrolled. We compared the proportions of the causative genes and the distributions of the pathogenic variants among these 3 regions.

RESULTS

The proportions of genetically solved cases were 29.4% in the Tohoku region (n = 500), 29.6% in the Kanto and Chubu regions (n = 196), and 29.7% in the Kyushu region (n = 508), which did not differ statistically (P = .99). No significant regional differences in the proportions of each causative gene in genetically solved patients were observed after correction by multiple testing. Among the 29 pathogenic variants detected in all 3 regions, only p.(Pro347Leu) in RHO was an autosomal dominant variant; the remaining 28 variants were found in autosomal recessive genes. Conversely, 78.6% (275/350) of the pathogenic variants were detected only in a single region, and 6 pathogenic variants (p.[Asn3062fs] in EYS, p.[Ala315fs] in EYS, p.[Arg872fs] in RP1, p.[Ala126Val] in RDH12, p.[Arg41Trp] in CRX, and p.[Gly381fs] in PRPF31) were frequently found in ≥ 4 patients in the single region.

CONCLUSION

We observed region-specific pathogenic variants in the Japanese population. Further investigations of causative genes in multiple regions in Japan will contribute to the expansion of the catalog of genetic variants causing RP.

Effects of the Gaze Fixation Position on AS-OCT Measurements of the Limbus and Extraocular Muscle Insertion Site Distance

PURPOSE

To investigate the effect of the gaze fixation position on measurement of the limbus and extraocular muscle (EOM) insertion site distance using anterior segment optical coherence tomography (AS-OCT).

METHODS

Patients undergoing horizontal EOM surgeries were enrolled in this prospective experimental study. The distance between the angle recess and the muscle insertion site was measured using AS-OCT while patients fixed their gaze laterally or medially at inner or outer gaze fixation. The distance between the limbus and muscle insertion was intraoperatively measured using calipers.

RESULTS

A total of 46 lateral rectus muscles and 36 medial rectus muscles of 44 patients were evaluated. Significant differences were observed between intra-operative measurements (6.3 ± 0.7 mm) and AS-OCT measurements (5.8 ± 0.7 mm) for the lateral rectus muscle at inner gaze fixation (P = .0017) and medial rectus muscle at outer gaze fixation (P = .0003); no difference was observed when the lateral rectus (6.4 ± 0.5 mm) and medial rectus (4.9 ± 0.6 mm) muscles were measured at outer and inner gaze fixation, respectively. Bland-Altman plots showed better consistency at outer gaze fixation than at inner gaze fixation for the lateral rectus muscle; the opposite was observed for the medial rectus muscle. More than 80% of the AS-OCT measurements were within 1 mm of the intraoperative measurements at outer gaze fixation for the lateral rectus muscle and inner gaze fixation for the medial rectus muscle.

CONCLUSIONS

Gaze fixation at outer gaze fixation for the lateral rectus muscle and inner gaze fixation for the medial rectus muscle was an appropriate technique to assess limbus and EOM insertion using AS-OCT. [J Pediatr Ophthalmol Strabismus. 2021;58(1):28-33.].

Usefulness of handheld electroretinogram system for diagnosing blue-cone monochromatism in children

PURPOSE

To report the diagnosis of three childhood patients with blue-cone monochromatism (BCM) using S-cone electroretinograms (ERG) recorded with RETeval^® Complete.

STUDY DESIGN

Prospective clinical study.

METHODS

We examined three boys initially suspected of having rod monochromatism. S-cone ERG was performed with red background and blue flashed light stimulation using two different intensities: 0.25 cd × s/m² and 1 cd × s/m².

RESULTS

Case 1 was a 12-year-old boy with a visual acuity of 0.1 OU. Case 2 was an 8-year-old boy with a visual acuity of 0.3 OD and 0.2 OS. Both cases showed a myopic fundus and nystagmus without any other ocular abnormalities. Case 3 was a 6-year-old boy with a visual acuity of 0.3 OD and 0.4 OS. He also showed myopic fundus changes, but nystagmus was not observed. Rod and maximal responses recorded with RETeval^® were likely to be within normal range; however, cone responses were absent in all cases. S-cone ERGs showed positive responses at 40 ms with 0.25 cd × s/m² intensity in Case 2, and at approximately 30-40 ms with 1.0 cd × s/m² intensity in all three cases. These ERG findings led to a diagnosis of BCM.

CONCLUSIONS

S-cone ERG of RETeval^® was helpful in diagnosing with minimal invasion BCM in childhood patients.

Analysis of IKBKG/NEMO gene in five Japanese cases of incontinentia pigmenti with retinopathy: fine genomic assay of a rare male case with mosaicism

Incontinentia pigmenti (IP) is an X-linked dominant genodermatosis that is usually lethal in utero in males, though exceptionally they survive very rarely either with Klinefelter syndrome or a somatic mosaicism. We performed genomic analysis of five Japanese IP patients including a rare boy case, all of whom were definite cases with retinopathy. Four patients including the boy revealed the recurrent exon 4-10 deletion in the sole known causative gene IKBKG/NEMO, which was confirmed by various specific PCR techniques. The boy's saliva DNA showed a mosaicism consisting of the deletion and intact alleles, but his blood DNA did not. Relative quantification analysis of the real-time PCR data by ∆∆CT method estimated the mosaicism ratio of the boy's saliva as 45:55 (deletion:intact). A genomic analysis for the recurrent deletion at the nucleotide sequence level has been performed directly using patient's DNA and it has been clarified that the breakpoints are within two MER67B repeats in the intron 3 and downstream of exon 10. This is the first report of the assay for the mosaicism ratio of a male IP case with a recurrent exon 4-10 deletion of IKBKG/NEMO and the sequencing analysis of the breakpoints of the recurrent deletion directly using patient's sample.

Sensorineural hearing loss and hypoplastic cochlea in Axenfeld-Rieger syndrome with FOXC1 mutation

OBJECTIVE

Axenfeld-Rieger syndrome (ARS) type 3 is a rare autosomal dominant disease, characterized by anterior segment dysgenesis of the eye, hearing loss, and cardiac defects. ARS type 3 is highly associated with FOXC1 mutations, which induces developmental disorders of neural crest cells. Most studies about ARS patients focused on ophthalmologic findings, but details in their hearing loss have not yet been revealed. In this report, we investigated audiological and otological manifestations in the ARS type 3 patient who had the novel heterozygous FOXC1 mutation leading deletion at the forkhead DNA-binding domain.

METHODS AND RESULTS

Pure tone audiometry showed bilateral sensorineural hearing loss (SNHL) and audiological examinations confirmed that major dysfunctions existed in the cochlea, rather than the spiral ganglion neurons and the cochlear nerve. CT and MRI revealed the hypoplastic cochlea at both sides. Given that the 6p25 deletion syndrome, lacking one allele of the FOXC1 gene, shows similar, but more severe cochlear malformations than the present case, the FOXC1 mutations might contribute to the hypoplasia and dysfunctions in the cochlea.

CONCLUSION

To our knowledge, this is the first report demonstrating that the ARS type 3 patient with the FOXC1 mutation has the hypoplasia and dysfunctions in the cochlea, which results in bilateral SNHL.

Multimodal therapy with surgery and adjuvant nivolumab for late-onset multiple liver metastases of choroidal malignant melanoma: a case report

BACKGROUND

Choroidal malignant melanoma is the most common primary malignant tumor of the eye in adults. Prognosis after recurrence of this disease has been dismal because of the absence of an effective therapy. However, resection of recurrent foci and a subsequent treatment with immune-checkpoint inhibitor may improve the prognosis after recurrence of this disease. This study presents a case of late-onset liver metastases of choroidal malignant melanoma, successfully treated with hepatectomy and postoperative adjuvant nivolumab.

CASE PRESENTATION

A 53-year-old woman had undergone left ocular enucleation because of choroidal malignant melanoma 13 years prior to admission. She visited a nearby clinic with complaints of epigastric pain. She was referred to our hospital because a giant liver tumor was observed on abdominal ultrasonography. Enhanced computed tomography revealed multiple liver tumors in the right lobe, 49 mm in diameter with ring enhancement in subsegment (S) 5/6, and 14 and 8 mm without any enhancement in S7 and S5, respectively. On magnetic resonance imaging, the main tumor showed high intensity on T1-weighted with fat suppression, suggesting melanin deposition. Based on the diagnosis of multiple liver metastases of choroidal malignant melanoma, right hepatectomy and regional lymphadenectomy were performed. She was discharged without postoperative complications. Histological examination revealed that all tumors were metastatic malignant melanoma. She was treated with nivolumab postoperatively, and no recurrences were observed during 22 months of follow-up.

CONCLUSIONS

Aggressive surgery plus adjuvant nivolumab appears to be a promising treatment for choroidal malignant melanoma with late-onset liver metastases.

SAT0010 ANTI-CD30 IMMUNOTHERAPY AMELIORATES BONE AND CARTILAGE DESTRUCTION IN EXPERIMENTAL MODEL OF RHEUMATOID ARTHRITIS IN MICE

Background:

CD30 is a member of the TNF-receptor family and commonly expressed on lymphocytes of Hodgkin lymphoma and anaplastic large cell lymphoma. It has been reported that levels of soluble CD30 in serum and joint fluid is significantly elevated in rheumatoid arthritis (RA). Although RA patients may develop lymphoproliferative disorders (LPD) as a result of immunosuppression by MTX or bDMARDs, safety medications after the regression of LPD for RA have not yet been established.

Objectives:

To explore the potential of CD30 targeting therapy for RA.

Methods:

(1) Immuno-histological staining of CD30 was performed for fresh synovial tissues of RA and osteoarthritis (OA). In addition, double immunofluorescence staining of CD30 with CD3, CD20, CD68, CD138 were performed on RA synovial tissue. (2) Brentuximab vedotin (BV) is an anti-CD30 antibody conjugated with monomethyl auristatin E, designed to induce apoptosis of CD30 expressing cells. A multiple myeloma cell line (RPMI8226) was used as a non-lymphoma cell line and plasma cell-like cell line. Immuno-cytological staining for CD30 was performed on RPMI8226. Cells were cultured and harvested on days 0, 1, and 3 to evaluate the effects of BV (50 μl / ml per well). Cytospin specimens were stained by May-Grunwald-Giemsa (MGG) staining for cell counting and by FIFC-terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining for detection of apoptosis. (3) Collagen antibody induced arthritis (CAIA) was induced in DBA/1 mice by arthritogenic cocktail of monoclonal antibodies against type II collagen. BV was administered to the treatment groups (30mg/kg and 70mg/kg n=4 each) and evaluated clinical score, histological findings and levels of SAA, IL-6, and TNFα in serum by ELISA. Student’st-test (two-tailed) was used to determine statistical significance for analysis of synovial tissues and cell line assay. Two way ANOVA with Dunnett’s post hoc analysis was used for multiple comparisons of mice model.

Results:

(1) The number of CD30-positive cells was significantly higher in RA synovial tissue than in OA synovial tissue (p<0.01) (Fig. 1). CD30-positive cells were detected around the lymphoid follicles. Double immunofluorescence showed CD30 and CD138 double-positive cells in the synovial tissue of RA, suggesting CD30 is predominantly expressed by plasma cells. (2) RPMI8226 cells expressed CD30. BV caused apoptosis of RPMI8226 cells, and the number of cells treated with BV decreased to 95% compared to controls. (3) All control mice (n=4) developed severe arthritis, and their scores reached a peak (score: 13.3) on day 10. In the mice of treatment group of 30 mg/kg, paw swelling was slightly decreased, their clinical score reached a peak (score: 9.3) on day 10. In contrast, paw swelling was significantly reduced in the 70 mg/kg treatment group. The peak of the clinical score was 4.3 on day 10 (Fig.2). Histological score evaluated synovitis with infiltration of inflammatory cells, pannus formation, and erosion of bone and cartilage. Histological score of hind paws were 3.0 ± 0.8 for the control group, 2.7 ± 1.0 for 30 mg/kg group, and 0.7 ± 1.1 for 70 mg/kg group (p<0.01), respectively. The serum levels of SAA and IL-6 of treatment group were lower than those of no treatment group (p<0.01).

Conclusion:

We showed the expression of CD30 on synovial tissue of RA and the expression of CD30 on plasma cells. In addition, the current study provides the first evidence that BV depletion of CD30-positive cells suppressed arthritis and osteochondral destruction in CAIA mice. Our results may provide an important clue for the development of an effective treatment for RA with iatrogenic immunodeficiency-related LPD.

Disclosure of Interests:

Minami Matsuhashi: None declared, Keiichiro Nishida Grant/research support from: K. Nishida has received scholarship donation from CHUGAI PHARMACEUTICAL Co., Eisai Co., Mitsubishi Tanabe Pharma and AbbVie GK., Speakers bureau: K. Nishida has received speaking fees from CHUGAI PHARMACEUTICAL Co., Eli Lilly, Janssen Pharmaceutical K.K., Eisai Co. and AYUMI Pharmaceutical Corporation., Yoshihisa Nasu: None declared, Ryuichi Nakahara: None declared, Masahito Watanabe: None declared, Yoshifumi Hotta: None declared, Toshifumi Ozaki: None declared

SAT0068 THE RECENT INCIDENCE OF SURGICAL SITE INFECTION AND DELAYED WOUND HEALING AFTER ELECTIVE ORTHOPAEDIC SURGERIES FOR PATIENTS WITH RHEUMATOID ARTHRITIS WHO TREATED WITH B/TSDMARDS

Background:

In Japan, Methotrexate (MTX) has been approved in 1999, the first biologic DMARD (bDAMRD) in 2003, and the Janus kinase (JAK) inhibitors have been used since 2013. Although it is expected that the recent advancement of drug therapy would contribute the decrease in the incidence of orthopaedic surgeries by preventing structural damages1, 2), we are still facing a considerable number of patients who require surgical interventions3).

Objectives:

To investigate the recent trends of patient’s background who underwent the orthopaedic surgery for rheumatoid arthritis, number of orthopaedic intervention, and the type of the surgery.

Methods:

We reviewed the records of 1569 patients with RA who underwent orthopedic surgeries between 2004 and 2019 in our institution. The mean age of patients was 62.8 (22-88) years-old with disease duration of 20.9 (0.5-64) years. Data of these patients such as age, disease duration, medication (Glucocorticoid; GC, MTX, b/tsDMARD), type of surgeries (total joint replacement; TJR, hand surgery, foot surgery, spine surgery, and others), and preoperative serum CRP level were collected. We analyzed the annual change of these demographic and clinical data. Then, we compared them between CRP negative (<1.5g/l) and CRP positive group. Cochran-Armitage trend test,χ square test, or unpaired T-test was performed for statistical analysis. P <0.05 was considered significant.

Results:

Among all cases, 426 cases (27.2%) were treated with b/tsDMARDs at the time of operation. MTX and GC were used in 937 cases (59.7%) and 1015 cases (64.7%), respectively. The mean age and disease duration of RA showed an increasing trend, although the CRP level was dramatically decreased during the study period. While the rate of MTX use has not changed significantly (p=0.102), the number of cases treated by b/ts DMARD increased significantly to 46.7% (p<0.001). In contrast, the rate of GC use dicreased significantly (p<0.001). Although the annual number of surgeries have not changed, the proportion of cases who performed TJR decreased dramatically (59.6% in 2011, 29.5% in 2019), and the surgeries for hand and foot increased significantly (p<0.001) (Fig 1). The annual mean preoperative CRP level also decreased from 18.8±1.95 to 4.89±0.81 (Fig2). Compared to CRP positive group (n=1,113), the patients in CRP negative group (n=446) showed significantly younger age(p<0.001), shorter disease duration (p=0.031), lower late of GC use, and a higher rate of b/tsDAMRD use. The proportion of patients who underwent TJR was significantly higher in CRP positive group (p<0.001).

Conclusion:

Along with the increasing use of b/tsDMARD, the preoperative disease control of RA, as well as the type of demanded surgeries have dramatically changed.

References:

[1] Yamanaka H, Tanaka E, Nakajima A, et al. A large observational cohort study of rheumatoid arthritis, IORRA: Providing context for today’s treatment options.Mod Rheumatol2020;30:1-6.

[2] Matsumoto T, Nishino J, Izawa N, et al. Trends in Treatment, Outcomes, and Incidence of Orthopedic Surgery in Patients with Rheumatoid Arthritis: An Observational Cohort Study Using the Japanese National Database of Rheumatic Diseases.J Rheumatol2017;44:1575-82.

[3] Momohara S, Tanaka S, Nakamura H, et al. Recent trends in orthopedic surgery performed in Japan for rheumatoid arthritis.Mod Rheumatol2011;21:337-42.

Disclosure of Interests:

Yoshifumi Hotta: None declared, Yoshihisa Nasu: None declared, Keiichiro Nishida Grant/research support from: K. Nishida has received scholarship donation from CHUGAI PHARMACEUTICAL Co., Eisai Co., Mitsubishi Tanabe Pharma and AbbVie GK., Speakers bureau: K. Nishida has received speaking fees from CHUGAI PHARMACEUTICAL Co., Eli Lilly, Janssen Pharmaceutical K.K., Eisai Co. and AYUMI Pharmaceutical Corporation., Minami Matsuhashi: None declared, Masahito Watanabe: None declared, Ryuichi Nakahara: None declared, Toshifumi Ozaki: None declared

SAT0023 THE ROLE OF ADAM12 UPREGULATED PROLIFERATION OF SYNOVIAL MEMBRANE IN RHEUMATOID ARTHRITIS

Background:

ADAM12 is a member of a disintegrin and metalloproteinase family and has been reported to participate in the development of a variety of tumors by degrading ECM and shed precursors, thus promoting cell proliferation, invasion, and metastasis1). Additionally, ADAM12 is involved in chondrocyte differentiation from osteoarthritis (OA) patients by regulation of TGFβ1-induced IGF-1 and RUNX-2 expressions2). However, there is no report on the role of ADAM12 for rheumatoid arthritis (RA).

Objectives:

To investigate the expression and role of ADAM12 in the synovial tissue of RA.

Methods:

(1) The expression of ADAM12 in synovial tissues from RA (18 cases), OA (5 cases) and healthy control (HC) (3 cases) was examined by immunohistochemistry. The synovial tissues of HC were obtained during surgery of hemiarthroplasty for bone tumors. Three researchers evaluated the positive cell ratio. The samples were scored according to the percentage of positive staining: 0 points (weak positive, positive expression was less than 5%), 1 point (moderate positive, positive expression was between 5% and 50%) and 2 points (strong positive, positive expression was greater than 50%). In addition, the samples were scored according to the staining intensity: 0 points (weak intensity), 1 point (moderate intensity) and 2 points (high intensity). (2) The cultured synovial fibroblasts obtained from RA patients at the surgery (RASF) were stimulated by TNFα (1, 5, 10 ng/mL), TGFβ1 (1, 5, 10 ng/mL), PDGF-BB (1, 5, 10 ng/mL) and TNFα+TGFβ1+PDGF-BB (all 10 ng/mL), and the expression levels of ADAM12 relative mRNA was examined by real-time PCR. (3) siADAM12 was transfected in RASF, and the proliferation was examined by WST-1 assay, and the expression of ADAM12 protein was examined by western blotting.

Results:

(1) ADAM12 positive cells were found in synovial lining cells, plasma cells, and vascular endothelial cells. ADAM12 was highly expressed in RA synovial tissues. The immunostaining scores of RA, OA, and HC were 3.9±0.01, 1.9±0.27, and 0.8±0.18, respectively. (2) Stimulation by TNFα, TGFβ1, and PDGF-BB resulted in the upregulation of the expression of ADAM12 relative mRNA in RASF, and TGFβ1 stimulation notably tended to increase the expression by about 5 to 6 times. (3) siADAM12 successfully suppressed the expression of ADAM12 protein and simultaneously suppressed the proliferation of RASF.

Conclusion:

ADAM12 might be involved in the pathogenesis of RA, promoting the cell proliferation of RASF.

References:

[1] Kyeiborg M, Albrechtsen R, Couchman J, et al., Cellular roles of ADAM12 in health and disease, Int J Biochem Cell Biol, 2008

[2] Masahiro H, Keiichiro N, Joe H, et al., Involvement of ADAM12 in Chondrocyte Differentiation by Regulation of TGF-beta1-Induced IGF-1 and RUNX-2 Expressions, Calcif Tissue Int, 2019

Disclosure of Interests:

Masahito Watanabe: None declared, Keiichiro Nishida Grant/research support from: K. Nishida has received scholarship donation from CHUGAI PHARMACEUTICAL Co., Eisai Co., Mitsubishi Tanabe Pharma and AbbVie GK., Speakers bureau: K. Nishida has received speaking fees from CHUGAI PHARMACEUTICAL Co., Eli Lilly, Janssen Pharmaceutical K.K., Eisai Co. and AYUMI Pharmaceutical Corporation., Yoshihisa Nasu: None declared, Ryuichi Nakahara: None declared, Minami Matsuhashi: None declared, Yoshifumi Hotta: None declared, Toshifumi Ozaki: None declared

FRI0523 THE RECENT TREND OF ORTHOPAEDIC SURGERIES FOR RHEUMATOID ARTHRITIS. AN ANALYSIS OF 1569 CASES FROM 2004 TO 2019

Background:

In Japan, Methotrexate (MTX) has been approved in 1999, the first biologic DMARD (bDAMRD) in 2003, and the Janus kinase (JAK) inhibitors have been used since 2013. Although it is expected that the recent advancement of drug therapy would contribute the decrease in the incidence of orthopaedic surgeries by preventing structural damages1, 2), we are still facing a considerable number of patients who require surgical interventions3).

Objectives:

To investigate the recent trends of patient’s background who underwent the orthopaedic surgery for rheumatoid arthritis, number of orthopaedic intervention, and the type of the surgery.

Methods:

We reviewed the records of 1569 patients with RA who underwent orthopedic surgeries between 2004 and 2019 in our institution. The mean age of patients was 62.8 (22-88) years-old with disease duration of 20.9 (0.5-64) years. Data of these patients such as age, disease duration, medication (Glucocorticoid; GC, MTX, b/tsDMARD), type of surgeries (total joint replacement; TJR, hand surgery, foot surgery, spine surgery, and others), and preoperative serum CRP level were collected. We analyzed the annual change of these demographic and clinical data. Then, we compared them between CRP negative (<1.5g/l) and CRP positive group. Cochran-Armitage trend test,χ square test, or unpaired T-test was performed for statistical analysis. P <0.05 was considered significant.

Results:

Among all cases, 426 cases (27.2%) were treated with b/tsDMARDs at the time of operation. MTX and GC were used in 937 cases (59.7%) and 1015 cases (64.7%), respectively. The mean age and disease duration of RA showed an increasing trend, although the CRP level was dramatically decreased during the study period. While the rate of MTX use has not changed significantly (p=0.102), the number of cases treated by b/ts DMARD increased significantly to 46.7% (p<0.001). In contrast, the rate of GC use dicreased significantly (p<0.001). Although the annual number of surgeries have not changed, the proportion of cases who performed TJR decreased dramatically (59.6% in 2011, 29.5% in 2019), and the surgeries for hand and foot increased significantly (p<0.001) (Fig 1). The annual mean preoperative CRP level also decreased from 18.8±1.95 to 4.89±0.81 (Fig 2). Compared to CRP positive group (n=1,113), the patients in CRP negative group (n=446) showed significantly younger age(p<0.001), shorter disease duration (p=0.031), lower late of GC use, and a higher rate of b/tsDAMRD use. The proportion of patients who underwent TJR was significantly higher in CRP positive group (p<0.001).

Conclusion:

Along with the increasing use of b/tsDMARD, the preoperative disease control of RA, as well as the type of demanded surgeries have dramatically changed.

References:

[1] Yamanaka H, Tanaka E, Nakajima A, et al. A large observational cohort study of rheumatoid arthritis, IORRA: Providing context for today’s treatment options.Mod Rheumatol2020;30:1-6.

[2] Matsumoto T, Nishino J, Izawa N, et al. Trends in Treatment, Outcomes, and Incidence of Orthopedic Surgery in Patients with Rheumatoid Arthritis: An Observational Cohort Study Using the Japanese National Database of Rheumatic Diseases.J Rheumatol2017;44:1575-82.

[3] Momohara S, Tanaka S, Nakamura H, et al. Recent trends in orthopedic surgery performed in Japan for rheumatoid arthritis.Mod Rheumatol2011;21:337-42.

Disclosure of Interests:

Yoshifumi Hotta: None declared, Yoshihisa Nasu: None declared, Keiichiro Nishida Grant/research support from: K. Nishida has received scholarship donation from CHUGAI PHARMACEUTICAL Co., Eisai Co., Mitsubishi Tanabe Pharma and AbbVie GK., Speakers bureau: K. Nishida has received speaking fees from CHUGAI PHARMACEUTICAL Co., Eli Lilly, Janssen Pharmaceutical K.K., Eisai Co. and AYUMI Pharmaceutical Corporation., Minami Matsuhashi: None declared, Masahito Watanabe: None declared, Ryuichi Nakahara: None declared, Toshifumi Ozaki: None declared

A case of childhood glaucoma with a combined partial monosomy 6p25 and partial trisomy 18p11 due to an unbalanced translocation

Background: Chromosomal deletion involving the 6p25 region results in a clinically recognizable syndrome characterized by anterior eye chamber anomalies with risk of glaucoma and non-ocular malformations (6p25 deletion syndrome). We report a newborn infant case of childhood glaucoma with a combination of partial monosomy 6p25 and partial trisomy 18p11 due to an unbalanced translocation.Materials and methods: The patient was a 0-year-old girl. Both eyes showed aniridia and left eye Peters anomaly with multiple malformations. To identify the chromosomal aberrations in the patient with clinically suspected 6p25 deletion syndrome, we performed cytogenetic analysis (G-banding and multicolor fluorescent in-situ hybridization) and array-based comparative genomic hybridization (array-CGH) analysis.Results: Cytogenetic analyses revealed a derivative chromosome 6 with its distal short arm replaced by an extra copy of the short arm of chromosome 18. Array-CGH analysis detected a 4.6-Mb deletion at 6pter to 6p25.1 and 8.9-Mb duplication at 18pter to 18p11.22. To determine the breakpoint of the unbalanced rearrangement at the single-base level, we performed a long-range PCR for amplifying the junctional fragment of the translocation breakpoint. By sequencing the junctional fragment, we defined the unbalanced translocation as g.chr6:pter_4594783delinschr18:pter_8911541.Conclusions: A phenotype corresponding to combined monosomy 6p25 and trisomy 18p11 presented as childhood glaucoma associated with non-acquired (congenital) ocular anomalies consist of aniridia and Peters anomaly and other systemic malformations. To the best of our knowledge, this is the first report which demonstrated the breakpoint sequence of an unbalanced translocation in a Japanese infant with childhood glaucoma.

Long-term observation of a Japanese mucolipidosis IV patient with a novel homozygous p.F313del variant of MCOLN1

Mucolipidosis type IV (MLIV) is an autosomal recessively inherited lysosomal storage disorder characterized by progressive psychomotor delay and retinal degeneration that is associated with biallelic variants in the MCOLN1 gene. The gene, which is expressed in late endosomes and lysosomes of various tissue cells, encodes the transient receptor potential channel mucolipin 1 consisting of six transmembrane domains. Here, we described 14-year follow-up observation of a 4-year-old Japanese male MLIV patient with a novel homozygous in-frame deletion variant p.(F313del), which was identified by whole-exome sequencing analysis. Neurological examination revealed progressive psychomotor delay, and atrophy of the corpus callosum and cerebellum was observed on brain magnetic resonance images. Ophthalmologically, corneal clouding has remained unchanged during the follow-up period, whereas optic nerve pallor and retinal degenerative changes exhibited progressive disease courses. Light-adapted electroretinography was non-recordable. Transmission electron microscopy of granulocytes revealed characteristic concentric multiple lamellar structures and an electron-dense inclusion in lysosomes. The in-frame deletion variant was located within the second transmembrane domain, which is of putative functional importance for channel properties.

Coexistence of GNAT1 and ABCA4 variants associated with Nougaret-type congenital stationary night blindness and childhood-onset cone-rod dystrophy

PURPOSE

A single variant (p.G38D) in the GNAT1 gene, encoding the rod-specific transducin α-subunit in phototransduction, has been reported only in one French family with Nougaret-type autosomal dominant congenital stationary night blindness (CSNB). We identified a Japanese family with Nougaret-type CSNB and cone-rod dystrophy (CORD).

METHODS

Five patients with CSNB and two patients with childhood-onset CORD were recruited. We performed a comprehensive ophthalmic examination including electroretinography (ERG). Disease-causing variants were identified by whole exome sequencing, with candidates confirmed by Sanger sequencing in nine family members.

RESULTS

The GNAT1 variant (p.G38D) was identified in all four CSNB patients, whereas the two CORD patients carried biallelic truncated known ABCA4 variants as well as the GNAT1 variant. Clinically, no remarkable findings were observed in fuduscopy, fundus autofluorescence, or optical coherence tomography images from the CSNB patients. No response was detectable by rod ERG. The a-waves of standard and bright flash ERG were delayed and broadened rather than biphasic, and b/a-wave amplitude ratio was negative. Cone and 30-Hz flicker responses were normal, and overall, the ERG findings were compatible with previous descriptions of Nougaret-type CSNB. ERG of the CORD patients with macular atrophy showed non-recordable rod response and severely decreased standard flash, cone and 30-Hz flicker responses.

CONCLUSIONS

This is the second report of a Nougaret-type CSNB family with the GNAT1 variant. Our novel findings suggest that coexistence of the GNAT1 and biallelic ABCA4 variants is associated with an overlapping phenotype with both Nougaret-type CSNB and CORD.

Retinal structure in Leber's congenital amaurosis caused by RPGRIP1 mutations

This study aimed to evaluate retinal structure in the early stage of Leber’s congenital amaurosis (LCA) caused by RPGRIP1 mutations. Four patients from two families were included. Case 1 was a 13-year-old girl, cases 2 and 3 were 7-year-old monozygotic twin brothers of case 1, and case 4 was a 17-year-old boy. Comprehensive ophthalmic examinations were performed, including visual acuity measurements, perimetry, electroretinography (ERG), and optical coherence tomography (OCT). To identify potential pathogenic mutations, 74 genes known to cause retinitis pigmentosa or LCA were assessed using targeted next-generation sequencing. OCT showed photoreceptor outer nuclear layer (ONL) thinning in all patients. The lamellar structure was retained in all patients, whereas the ellipsoid zone was extinguished in cases 1, 2, and 3. In case 4, the ellipsoid zone was maintained at 9 years of age but became blurred at 17 years of age. In case 1, OCT indicated slight photoreceptor ONL thinning during the period between 7 and 11 years of age. Mutation analysis revealed RPGRIP1 mutations as the cause for autosomal recessive LCA in all patients. Photoreceptor ONL on OCT is relatively well preserved in the early stage of LCA caused by RPGRIP1 mutations.

Researchers in Japan have characterized the early stages of the inherited retinal disease Leber’s congenital amaurosis (LCA), raising hope that gene therapy could help before the disease progresses too far. LCA results in early-onset blindness or severe visual impairment and has been linked with several genes, including RPGRIP1. Daisuke Miyamichi from Hamamatsu University School of Medicine, Japan, and coworkers conducted ophthalamic tests on four young patients with RPGRIP1 mutations. In all four cases, they found thinning of the photoreceptor outer nuclear layer, a layer of the retina. The outer nuclear layer progressively thinned in consecutive samples taken from the same patient at different ages, and was better retained in the younger patients. Taken together, these findings suggest that gene therapy to correct RPGRIP1 mutations could be effective if carried out in early childhood.

Genetic characteristics of retinitis pigmentosa in 1204 Japanese patients

BACKGROUND

The genetic profile of retinitis pigmentosa (RP) in East Asian populations has not been well characterised. Therefore, we conducted a large-scale sequencing study to investigate the genes and variants causing RP in a Japanese population.

METHODS

A total of 1209 Japanese patients diagnosed with typical RP were enrolled. We performed deep resequencing of 83 known causative genes of RP using next-generation sequencing. We defined pathogenic variants as those that were putatively deleterious or registered as pathogenic in the Human Gene Mutation Database or ClinVar database and had a minor allele frequency in any ethnic population of ≤0.5% for recessive genes or ≤0.01% for dominant genes as determined using population-based databases.

RESULTS

We successfully sequenced 1204 patients with RP and determined 200 pathogenic variants in 38 genes as the cause of RP in 356 patients (29.6%). Variants in six genes (EYS, USH2A, RP1L1, RHO, RP1 and RPGR) caused RP in 65.4% (233/356) of those patients. Among autosomal recessive genes, two known founder variants in EYS [p.(Ser1653fs) and p.(Tyr2935*)] and four East Asian-specific variants [p.(Gly2752Arg) in USH2A, p.(Arg658*) in RP1L1, p.(Gly2186Glu) in EYS and p.(Ile535Asn) in PDE6B] and p.(Cys934Trp) in USH2A were found in ≥10 patients. Among autosomal dominant genes, four pathogenic variants [p.(Pro347Leu) in RHO, p.(Arg872fs) in RP1, p.(Arg41Trp) in CRX and p.(Gly381fs) in PRPF31] were found in ≥4 patients, while these variants were unreported or extremely rare in both East Asian and non-East Asian population-based databases.

CONCLUSIONS

East Asian-specific variants in causative genes were the major causes of RP in the Japanese population.

Phenotypic Features of Oguchi Disease and Retinitis Pigmentosa in Patients with S-Antigen Mutations: A Long-Term Follow-up Study

PURPOSE

To present phenotypic features of 22 patients with S-antigen (SAG) mutations.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Twenty-one Japanese patients from 16 families with a homozygous c.924delA mutation and 1 patient with a homozygous c.636delT mutation in the SAG gene.

METHODS

Clinical records on symptoms; best-corrected visual acuity; and Goldmann perimetry, fundus photography, fundus autofluorescence (FAF), OCT, and electroretinography results were reviewed.

MAIN OUTCOME MEASURES

Best-corrected visual acuity, Goldmann perimetry results, imaging findings, and electroretinography results.

RESULTS

Ten patients had Oguchi disease and 12 had retinitis pigmentosa (RP) with mean follow-up periods of 13.8 and 10.2 years, respectively. Retinitis pigmentosa patients were older (mean age, 56.0 years) than those with Oguchi disease (mean age, 22.1 years; P < 0.001) at the initial visit. Night blindness noted in childhood was the most common initial symptom for both Oguchi disease (80.0%) and RP (91.7%) patients. Best-corrected visual acuity in the logarithm of the minimum angle of resolution (logMAR) was well preserved in Oguchi disease patients (mean, 0.02 logMAR in both eyes) but reduced in most RP patients (mean, 1.32 logMAR [right eye] and 1.35 logMAR [left eye]). Similarly, the visual field in the retinal area was preserved in Oguchi disease patients (mean, 677 mm² right eye and 667 mm² left eye) and reduced in RP patients (mean, 369 mm² right eye and 294 mm² left eye). Fundus images revealed a characteristic golden sheen with no retinal degeneration in Oguchi disease patients, excluding 2 with macular degeneration detected by FAF, OCT, or both and 1 with mild retinal degeneration confirmed by OCT and fluorescein angiography. Pigmentary retinal degeneration most evident posteriorly was observed in RP patients, accompanied by a characteristic golden sheen in 12 of 14 patients undergoing ultra-widefield fundus imaging. OCT showed disrupted macular structure, and FAF revealed variable hypofluorescence. Electroretinography identified absent rod responses in both diseases, along with relative preservation of cone responses in Oguchi disease patients. Three patients showed progressive loss of the golden sheen based on fundus images, including 1 who demonstrated RP 26 years after the initial diagnosis of Oguchi disease.

CONCLUSIONS

Retinitis pigmentosa with SAG mutations often shows a characteristic golden sheen surrounding posterior pigmentary retinal degeneration. Oguchi disease can show progressive degeneration in adulthood, rarely resulting in RP.

Multicenter open-label randomized phase II study of second-line panitumumab and irinotecan with or without fluoropyrimidines in patients with KRAS wild-type metastatic colorectal cancer (PACIFIC study)

This phase II clinical trial compared the efficacy and safety of second-line irinotecan and panitumumab treatment (IRI + Pmab) with that of irinotecan, fluoropyrimidines and panitumumab treatment (control) in patients with KRAS wild-type mCRC. The primary endpoint was progression-free survival. In addition, early predictive markers of treatment efficacy were explored. Eighty patients were planned to be recruited. Due to a slow accrual rate, only 48 patients were recruited from 2012 to 2016, of which 23 were allocated to the control group and 25 were allocated to the IRI + Pmab group. The median progression-free survival was 254 days (95% confidence interval, 159-306) for control, and 190 days (95% confidence interval, 159-213) for IRI + Pmab (log-rank test, P = 0.26). The response rate without confirmation was 21.7% (5/23) for control and 40.0% (10/25) for IRI + Pmab. Neutropenia, leukopenia, and anorexia were the most common Grade 3/4 adverse events, and several early drop-outs from the treatment protocol were observed in the control group. As for the biomarkers, carcinoembryonic antigen and lactate dehydrogenase (LDH) smoothly declined immediately after the initial dosing in patients with a partial response or stable disease. After starting treatment, LDH-1 and - 2 increased, while LDH-4 and - 5 decreased, irrespective of tumor response. However, exceptions were frequent. In conclusion, this study failed to prove the safety and efficacy of irinotecan and panitumumab treatment due to insufficient patient accrual. Although LDH and its isozymes changed after initiation of treatment, their ability to predict the tumor response may not surpass that of carcinoembryonic antigen levels.The University Hospital Medical Information Network Clinical Trial Registry: UMIN000007658.

Genotype determination of the OPN1LW/OPN1MW genes: novel disease-causing mechanisms in Japanese patients with blue cone monochromacy

Blue cone monochromacy (BCM) is characterized by loss of function of both OPN1LW (the first) and OPN1MW (the downstream) genes on the X chromosome. The purpose of this study was to investigate the first and downstream genes in the OPN1LW/OPN1MW array in four unrelated Japanese males with BCM. In Case 1, only one gene was present. Abnormalities were found in the promoter, which had a mixed unique profile of first and downstream gene promoters and a -71A > C substitution. As the promoter was active in the reporter assay, the cause of BCM remains unclear. In Case 2, the same novel mutation, M273K, was present in exon 5 of both genes in a two-gene array. The mutant pigments showed no absorbance at any of the wavelengths tested, suggesting that the mutation causes pigment dysfunction. Case 3 had a large deletion including the locus control region and entire first gene. Case 4 also had a large deletion involving exons 2-6 of the first gene. As an intact LCR was present upstream and one apparently normal downstream gene was present, BCM in Case 4 was not ascribed solely to the deletion. The deletions in Cases 3 and 4 were considered to have been caused by non-homologous recombination.

Changes in conjunctival-scleral thickness after strabismus surgery measured with anterior segment optical coherence tomography

PURPOSE

To evaluate changes in conjunctival-scleral thickness following strabismus surgery with anterior segment optical coherence tomography (AS-OCT).

STUDY DESIGN

Prospective, observational, consecutive case series.

METHODS

Distances between the conjunctival epithelium and inner scleral wall were measured with AS-OCT before and 3-5 months after strabismus surgery. The measurements were performed at 1.5 mm (limbus), 7.0 mm (insertion), and 8.0 mm (tendon) posterior to the scleral spur on the lateral rectus muscle (LR); and 1.5 mm (limbus), 4.0 mm (insertion), and 5.5 mm (tendon) posterior to the scleral spur on the medial rectus muscle (MR). Thirty-three extraocular muscles (20 LRs and 13 MRs) from 23 subjects were studied.

RESULTS

Thicknesses were significantly less at the insertion (0.95-0.78 mm; p < 0.001) and tendon (0.99-0.78 mm; p < 0.001) after LR recession and at the tendon (1.21-0.92 mm; p = 0.02) after MR recession. Thicknesses were significantly greater at the insertion (0.82-1.07 mm; p = 0.01) and tendon (0.95-1.28 mm; p = 0.01) after MR resection or plication and at the limbus, insertion, and tendon (0.75-0.90 mm, 0.94-1.19 mm, 1.03-1.28 mm, respectively; all p = 0.04) after LR resection or plication.

CONCLUSION

Conjunctival-scleral thicknesses showed various changes after recession and resection or plication. These findings may help detect previous surgical operations when conjunctival scarring and ciliary vessel changes are unclear.

Visual Outcomes in Japanese Patients with Retinitis Pigmentosa and Usher Syndrome Caused by USH2A Mutations

PURPOSE

EYS and USH2A are the most common causative genes for retinitis pigmentosa (RP) in Japan. We determined the clinical outcomes for USH2A-related non-syndromic RP or Usher syndrome type II (USH2).

METHODS

Two non-syndromic RP and 11 USH2 patients with previously identified USH2A mutations were included. Their complete history and medical records were collected using standard procedures. Visual fields and acuity were compared with those of patients with EYS mutations. Clinical analyses were based on ophthalmic and otolaryngologic examinations.

RESULTS

In all patients, the fundus displayed changes typical of RP. Most patients showed relatively well-preserved visual acuity in their thirties or forties, with rapid deterioration in their fifties. Concentric constriction started in the twenties or thirties, and no effective residual visual field was observed after the fifties.

CONCLUSIONS

The visual outcome for non-syndromic RP or USH2 patients with USH2A mutations is consistent with that for RP patients with EYS mutations.