Development of angiogenic periglomerular microvessels after acute glomerular lesions in IgA nephropathy.

AIM: To clarify the clinicopathological characteristics and role of periglomerular angiogenesis in IgA nephropathy. METHODS AND RESULTS: The renal biopsy specimens of 114 patients with IgA nephropathy were examined. Among them, 46 (40%) showed periglomerular angiogenesis around the glomeruli. CD34 and α-smooth muscle actin (α-SMA) staining in serial sections revealed that these vessels contained CD34+ α-SMA+ microarterioles along with CD34+ α-SMA- capillaries. We termed these "periglomerular microvessels (PGMVs)". Patients with PGMVs (PGMV group) had clinically and histologically more severe disease than those without PGMVs (non-PGMV group) at the time of biopsy. Even after adjusting for age, there were significant differences in the degree of proteinuria and estimated glomerular filtration rate reduction between the PGMV and non-PGMV groups. The PGMV group showed a higher incidence of segmental and global glomerulosclerosis and crescentic lesions than the non-PGMV group (P < 0.01). Here, PGMVs were undetectable in the acute and active inflammation phase, but were observed in the acute to chronic or chronic glomerular remodelling phase. PGMVs mainly developed around glomerular adherent lesions to the Bowman's capsule with small or minimal glomerular sclerotic lesions. Conversely, they were rarely observed in segmental sclerosis areas. CONCLUSION: The PGMV group is clinically and pathologically more severe than the non-PGMV group; however, they were undetectable in segmental sclerosis with mesangial matrix accumulation. PGMVs might occur after acute/active glomerular lesions, suggesting that PGMVs may inhibit segmental glomerulosclerosis progression and could be a marker for good repair response after acute/active glomerular injury in severe IgA nephropathy cases.

A case of seronegative primary Sjögren's syndrome complicated by Takayasu arteritis in a Japanese girl.

In paediatric primary Sjögren's syndrome (SS), the initial symptoms manifest systemically, such as fever, general fatigue, and lymphadenopathy, rather than sicca symptoms. Most children with primary SS have autoantibodies, such as antinuclear, anti-Ro/SS-A, and/or anti-La/SS-B antibodies; however, some patients are seronegative. Similar to paediatric patients with primary SS, those with Takayasu arteritis (TAK) initially only present constitutional symptoms, making it difficult to suspect, unless characteristic features are present. To our knowledge, there have been no reports of the coexistence of both diseases in children. We present a rare case of seronegative SS complicated by TAK in a 9-year-old girl who presented with a persistent low-grade fever, general fatigue, cervical lymphadenopathy, and multiple caries. Although blood examination revealed all autoantibodies to be negative, a lip biopsy revealed lymphocytic sialadenitis, and a sialoscintigraphy indicated hypofunctional salivary glands, leading to the diagnosis of seronegative SS. The patient was treated with low-dose glucocorticoid and immunosuppressant administration to inhibit persistent inflammation and the progression of salivary gland dysfunction; although the symptoms resolved, inflammatory markers remained elevated. When the patient was 14 years old, cervical bruits were incidentally found, and TAK was suspected based on cervical ultrasonography and magnetic resonance angiography findings. 18F-fluorodeoxyglucose-positron emission tomography/computed tomography results demonstrated increased fluorodeoxyglucose accumulation from the ascending to descending aorta. Therefore, she was diagnosed with SS complicated by TAK, which is rare. Aortitis should be suspected when the cause of persistent inflammation cannot be ascertained in patients with SS.

Drinking hydrogen water improves photoreceptor structure and function in retinal degeneration 6 mice.

Retinitis pigmentosa (RP) is a genetically heterogeneous group of inherited retinal disorders involving the progressive dysfunction of photoreceptors and the retinal pigment epithelium, for which there is currently no treatment. The rd6 mouse is a natural model of autosomal recessive retinal degeneration. Given the known contributions of oxidative stress caused by reactive oxygen species (ROS) and selective inhibition of potent ROS peroxynitrite and OH·by H2 gas we have previously demonstrated, we hypothesized that ingestion of H2 water may delay the progression of photoreceptor death in rd6 mice. H2 mice showed significantly higher retinal thickness as compared to controls on optical coherence tomography. Histopathological and morphometric analyses revealed higher thickness of the outer nuclear layer for H2 mice than controls, as well as higher counts of opsin red/green-positive cells. RNA sequencing (RNA-seq) analysis of differentially expressed genes in the H2 group versus control group revealed 1996 genes with significantly different expressions. Gene and pathway ontology analysis showed substantial upregulation of genes responsible for phototransduction in H2 mice. Our results show that drinking water high in H2 (1.2-1.6 ppm) had neuroprotective effects and inhibited photoreceptor death in mice, and suggest the potential of H2 for the treatment of RP.

Transitioning from paediatric to adult rheumatological healthcare: English summary of the Japanese Transition Support Guide.

Issues related to transitioning from paediatric to adult healthcare are currently receiving international attention. In Japan, 1000 patients with childhood-onset chronic rheumatological diseases reach adulthood every year and require transition from care by paediatric to care by adult rheumatologists. Here, we propose a guide for the latter, wherein the adult caregiver poses the clinical questions about transitional support that they need to have answered, and the paediatric caregiver mainly compiles the plans for the transition. To formulate the guide, we sought comments from both the Japan College of Rheumatology and the Pediatric Rheumatology Association of Japan and obtained their approval. Here, we present the outcome of this consultation in the form of a Guide for Supporting Transitional Care, aiming to provide essential knowledge to physicians in the fields of adult internal medicine and orthopaedics who may be involved in treating patients with rheumatic disease during the transition from paediatric to adult care. The features of transitional support that are common for patients with various different rheumatic diseases are presented in this guide, with the aim of informing policy and strategies to deliver optimal outcomes in transitional care by non-paediatric rheumatologists.

Clinical practice guidance for childhood-onset systemic lupus erythematosus-secondary publication.

Childhood-onset systemic lupus erythematosus (cSLE) has been recognised as a more acute and severe autoimmune disease than adult-onset SLE. With the development of medications for the disease and supportive therapy, the mortality rate associated with cSLE has drastically improved; the 10-year survival rate among patients with cSLE between 1995 and 2006 in Japan was 98.3%. However, the 10-year survival rate without any permanent functional impairment remained low at 66.1%. Therefore, the current treatment goal for cSLE is to ensure that they can perform normal daily activities throughout their lives by preventing the occurrence and/or progression of organ damage. For this purpose, appropriate treatments and evaluations are required according to the severity and risk of organ damage; however, there are no established guidelines for cSLE. Therefore, the Pediatric Rheumatology Association of Japan and the Pediatric Rheumatology Subcommittee in the Japan College of Rheumatology developed a comprehensive guidance for clinical practice based on cSLE-related data collected from Japanese national surveys and relevant articles from both domestic and international sources. However, due to the lack of indications for defined and objective evidence quality levels, this guidance should be used on the basis of the judgement of the attending physicians for individual patients.

Identification of novel OCRL isoforms associated with phenotypic differences between Dent disease-2 and Lowe syndrome.

BACKGROUND: Although Lowe syndrome and Dent disease-2 are caused by Oculocerebrorenal syndrome of Lowe (OCRL) mutations, their clinical severities differ substantially and their molecular mechanisms remain unclear. Truncating mutations in OCRL exons 1-7 lead to Dent disease-2, whereas those in exons 8-24 lead to Lowe syndrome. Herein we identified the mechanism underlying the action of novel OCRL protein isoforms. METHODS: Messenger RNA samples extracted from cultured urine-derived cells from a healthy control and a Dent disease-2 patient were examined to detect the 5' end of the OCRL isoform. For protein expression and functional analysis, vectors containing the full-length OCRL transcripts, the isoform transcripts and transcripts with truncating mutations detected in Lowe syndrome and Dent disease-2 patients were transfected into HeLa cells. RESULTS: We successfully cloned the novel isoform transcripts from OCRL exons 6-24, including the translation-initiation codons present in exon 8. In vitro protein-expression analysis detected proteins of two different sizes (105 and 80 kDa) translated from full-length OCRL, whereas only one protein (80 kDa) was found from the isoform and Dent disease-2 variants. No protein expression was observed for the Lowe syndrome variants. The isoform enzyme activity was equivalent to that of full-length OCRL; the Dent disease-2 variants retained >50% enzyme activity, whereas the Lowe syndrome variants retained <20% activity. CONCLUSIONS: We elucidated the molecular mechanism underlying the two different phenotypes in OCRL-related diseases; the functional OCRL isoform translated starting at exon 8 was associated with this mechanism.

A case of IgA vasculitis with necrotizing arteritis in a 13-year-old girl.

IgA vasculitis (IgAV) is the most frequent form of vasculitis in childhood which classically presents with purpura of the lower extremities, joint pain or swelling and abdominal pain. Though it is a self-limiting disease, and its prognosis is generally good, glomerulonephritis is one of the most important complications. IgAV is classified as a small vessel vasculitis, and though glomerulonephritis develops in IgAV, necrotizing arteritis is rarely seen. Here, we present a case of a 13-year-old girl with IgAV, glomerulonephritis, and necrotizing arteritis in the small renal arteries. There have been only a few reports of adult cases of IgAV with necrotizing arteritis in the kidneys, but there have been no pediatric cases. Some previous reports showed a high mortality rate and implied the possibility of overlap with other vasculitides. In the current report, a rare case of IgAV is described which exhibited necrotizing arteritis rather than overlap with another vasculitis, with a relatively typical clinical course for IgAV and laboratory tests.

Brain-derived Neurotrophic Factor in the Aqueous Humor of Glaucoma Patients.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) may be involved in the pathogenesis of glaucoma. BDNF concentrations reported in previous studies have varied widely, and the concentration of BDNF in aqueous humor is unknown. In this study, BDNF concentrations in the aqueous humor of glaucoma patients and control patients were measured with ELISA kits. METHODS: This prospective, observational study examined BDNF levels in aqueous humor in 62 eyes of 43 patients who underwent cataract surgery or trabeculectomy (11 glaucoma patients and 32 non-glaucoma cataract patients as controls). BDNF concentrations were examined by 4 different enzyme-linked immunosorbent assay (ELISA) techniques. RESULTS: The mean ± SD patient age was 72.0 ± 10.1 (range 35 to 87) years. Two of the techniques detected no BDNF in aqueous humor in any samples (n=3 and n=9, respectively); the average value was less than zero. An ultrasensitive ELISA kit did not yield reliable measurements. Finally, in an even more sensitive ELISA (Simoa-HD1), performed by an outside contractor, 25 (54.3%) eyes were below the detection limit, including 20 (55.6%) control and 5 (50%) glaucoma cases. For eyes with detectable BDNF, the overall BDNF concentration was 0.158 pg/mL (n=21): 0.196 pg/mL (n=16) in controls and 0.034 pg/mL (n=5) in glaucoma cases. CONCLUSIONS: BDNF level in aqueous humor varies widely.

Clinical Courses of IKAROS and CTLA4 Deficiencies: A Systematic Literature Review and Retrospective Longitudinal Study.

IKAROS and CTLA4 deficiencies are inborn errors of immunity and show similar clinical phenotypes, including hypogammaglobulinemia and autoimmune diseases (ADs). However, the differences in clinical features and pathogenesis of these are not fully understood. Therefore, we performed systematic literature reviews for IKAROS and CTLA4 deficiencies. The reviews suggested that patients with IKAROS deficiency develop AD earlier than hypogammaglobulinemia. However, no study assessed the detailed changes in clinical manifestations over time; this was likely due to the cross-sectional nature of the studies. Therefore, we conducted a retrospective longitudinal study on IKAROS and CTLA4 deficiencies in our cohort to evaluate the clinical course over time. In patients with IKAROS deficiency, AD and hypogammaglobulinemia often develop in that order, and AD often resolves before the onset of hypogammaglobulinemia; these observations were not found in patients with CTLA4 deficiency. Understanding this difference in the clinical course helps in the clinical management of both. Furthermore, our results suggest B- and T-cell-mediated ADs in patients with IKAROS and CTLA4 deficiencies, respectively.

Serum Brain-Derived Neurotrophic Factor in Glaucoma Patients in Japan: An Observational Study.

PURPOSE: The aim of this study was to measure serum levels of brain-derived neurotrophic factor (BDNF) in Japanese patients with primary open angle glaucoma (POAG) and normal tension glaucoma (NTG). METHODS: This was a prospective observational study of serum BDNF levels in 78 patients who underwent cataract surgery or trabeculectomy (27 glaucoma patients and 51 non-glaucoma cataract patients as controls). Patient age was 68.8 ± 11.1 years (mean ± standard deviation; range 35-86 years). The numbers of patients with POAG and NTG were 16 and 11, respectively. POAG was diagnosed by intraocular pressure measurement, gonioscopy, optic nerve head change, and presence of a visual field defect. RESULTS: Serum BDNF concentration was significantly lower in the glaucoma group (including both POAG and NTG) than in the control group (7.2 ± 3.6 ng/mL vs. 12.2 ± 9.3 ng/mL, p=0.004). Serum BDNF concentration was lower in early glaucoma than in moderate glaucoma. There was no correlation between serum BDNF concentration and age. When patients with NTG and POAG were compared, serum BDNF concentration was lower in the former. Serum BDNF concentration was not significantly correlated with glaucoma parameters, including optical coherence tomography and visual field defects. CONCLUSION: This is the first study to investigate serum BDNF concentration in glaucoma patients in Japan. Future studies should evaluate the role of BDNF as a potential biomarker of glaucoma.

Safety and effectiveness of adalimumab in Japanese patients with juvenile idiopathic arthritis: Results from a real-world postmarketing study.

OBJECTIVES: This study was conducted to assess the real-world safety and effectiveness of adalimumab in patients with juvenile idiopathic arthritis (JIA). METHODS: In this all-case, postmarketing surveillance study (NCT01412021) conducted in Japan, patients receiving adalimumab for JIA affecting multiple joints were observed for 24 weeks. The safety (adverse drug reactions [ADRs]/serious ADRs) and effectiveness (4-variable Disease Activity Score in 28 joints using erythrocyte sedimentation rate [DAS28-4/ESR] remission rate) were assessed. RESULTS: In the safety population (n = 356), 90.3% (65/72; weight, ≥15-<30 kg) of patients received adalimumab 20 mg every 2 weeks (q2w) and 98.3% (236/240; weight ≥30 kg) received 40 mg q2w. Incidence of ADRs and serious ADRs was 29.8% (106/356) and 3.4% (12/356), respectively. Incidence of ADRs was significantly higher in patients aged <15 years vs. ≥15 years (34.6% vs. 21.1%, p = .0072), those with comorbidities vs. without (38.3% vs. 25.7%, p = .0155), and those receiving dose <40 mg q2w vs. ≥40 mg q2w (38.8% vs. 26.9%, p = .0418). DAS28-4/ESR remission rate improved from 21.7% (36/166) at baseline to 74.7% (112/150) at week 24. CONCLUSIONS: Adalimumab was well tolerated and had acceptable safety and effectiveness in patients with JIA in the real-world setting.

Pediatric Dual-Energy X-Ray Absorptiometry in Japan: A Proposal for Shared Access to Equipment.

BACKGROUND: Regular assessment of bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) is essential for detecting glucocorticoid-induced osteoporosis in juvenile-onset autoimmune diseases. Z-score is used to standardize osteoporosis assessment in children and is evaluated with only one of three devices in Japan. The purpose of this study was to determine how many Japanese medical facilities for pediatric rheumatic diseases were unable to use Z-scores to evaluate osteoporosis. METHODS: Electronic questionnaires were distributed between 2017 and 2019 to hospitals belonging to the Pediatric Rheumatology Association of Japan and to university hospitals and public children's hospitals that provide medical care for pediatric rheumatic diseases. The questionnaire inquired about the location of DXA measurement, manufacturer (Hologic, GE healthcare, Hitachi), and measurement site, and the answers were collected using Google Forms. Statcel 4 was used for analysis. RESULTS: Overall, 120 facilities responded to the survey, of which 117 had DXA. In the remaining three facilities, DXA was not installed in two and was out of order in one. Bone loss in childhood was evaluated using a Z-score calculated from age-based reference values; however, 30% of hospitals without HOLOGIC DXA could not evaluate osteoporosis by Z-score in Japanese childhood. The characteristics of the hospitals enrolled in this study did not bias the selection of Hologic DXA. CONCLUSIONS: Neighboring institutions should consider sharing access to Hologic DXA equipment, to ensure use of uniform reference values. GE BMD reference values should be established for Japanese children.

Role of Pediatric Departments in Community Hospitals in Countermeasures against Measles Epidemics at Olympic Games Sites.

BACKGROUND: In preparation for the 2021 Tokyo Olympic/Paralympic Games, the Japanese government assessed the risks of infectious disease outbreaks and identified necessary preparations. This present study reviewed efforts made during a previous measles epidemic and describes the roles of hospitals. METHODS: This descriptive study investigated the records of 198 children with measles. All children were treated at a general hospital during the period from January 1997 through February 1998. We also examined the actions of pediatricians during and after a measles outbreak in the community. RESULTS: Of the 198 children, 145 (73%) were hospitalized. The measles vaccination rate in the previous year was approximately 75%. Of the patients examined, 53% were younger than 2 years of age; mean age was 2.75 years. Pneumonia and gastroenteritis accounted for 46% and 30% of the complications, respectively. Issues requiring attention included the number of hospital beds located in a negative pressure room or private room with a window, the need for gamma globulin preparations with high measles antibody titers, the necessity of increasing vaccination opportunities, and extension of physician working hours. CONCLUSIONS: Visitors from other countries could cause measles outbreaks in Japan. Measures that might mitigate an outbreak were maintenance of high vaccination rates, ready availability of information on the location of negative pressure hospital rooms, knowledge of the status of the measle outbreak, and flexible medical staffing. There is a risk of measles outbreaks among infants and among those who do not have a measles antibody titer.

Real-world Safety and Effectiveness of Infliximab in Pediatric Patients With Acute Kawasaki Disease: A Postmarketing Surveillance in Japan (SAKURA Study).

BACKGROUND: In 2015, infliximab was approved for the treatment of patients with intravenous immunoglobulin-refractory Kawasaki disease (KD) in Japan. However, limited real-world data exist on the usefulness of infliximab for acute KD patients. We conducted a postmarketing surveillance study in patients with acute KD refractory to conventional therapies to evaluate the safety (including any live vaccine-related infections) and the effectiveness of infliximab. METHODS: This was a multicenter, prospective, open-label, single-cohort, observational study in patients with acute KD refractory to conventional therapy who were prescribed a single 5 mg/kg dose of infliximab. Safety and effectiveness of infliximab were evaluated at 1 month, and live vaccine-related infections were further observed until 6 months from KD onset. Effectiveness assessments included fever resolution rate, the incidence of coronary artery lesions and change in coronary diameter Z scores. RESULTS: A total of 291 patients were enrolled, and all patients completed the study. Adverse drug reactions and serious adverse drug reactions were reported in 12.4% and 3.1% of patients, respectively. Live vaccine-related infections were not observed. In the 208 patients with effectiveness assessments, the fever resolution rate within 48 hours after infliximab infusion was 77.4% (95% confidence interval: 71.1-82.9). Median time until fever resolution was 16.6 hours. After infliximab administration, the incidence (at baseline: 10.9%; at the final observation point: 12.0%; maximum value: 14.6%) and severity of coronary artery lesions did not change notably. CONCLUSIONS: In this study, Infliximab for patients with acute KD refractory to conventional therapies was well tolerated and effective.

Beta-Blocker Therapy Preserves Normal Splenic T-Lymphocyte Numbers Reduced in Proportion to Sepsis Severity in a Sepsis Model.

Lymphocyte cell death contributes to sepsis-induced immunosuppression, leading to poor prognosis. This study examined whether sepsis severity and beta-blocker therapy could affect the degree of T-lymphocyte cell death in a mouse model of sepsis. In the first control study, 20 animals were allocated to 4 groups: control group with sham operation (group C, n = 5) and 3 groups with cecum ligation and puncture (CLP) performed at 3 different sites: proximal, middle, and distal cecum (groups CLP-P, CLP-M, and CLP-D, respectively; n = 5 in each group). Their spleens were resected under general anesthesia 24 hours after CLP, and the total number of normal splenic T lymphocytes per mouse and the percentage of apoptotic T lymphocytes were evaluated using flow cytometry. In the second experimental study, the effect of the beta-blocker esmolol was examined in CLP-P (group CLP-PE vs. CLP-P; n = 5 in each group). The total normal splenic T-lymphocyte numbers per mouse significantly decreased in proportion to CLP severity (group C, 18.6 × 106 (15 × 106-23.6 × 106); CLP-D, 9.2 × 106 (8.8 × 106-9.8 × 106); CLP-M, 6.7 × 106 (6.3 × 106-7.0 × 106); and CLP-P, 5.3 × 106 (5.1 × 106-6.8 × 106)). Beta-blocker therapy restored T-lymphocyte numbers (group CLP-PE vs. CLP-P; 6.94 ± 1.52 × 106 vs. 4.18 ± 1.71 × 106; p=0.027) without affecting apoptosis percentage. Beta-blocker therapy might improve sepsis-induced immunosuppression via normal splenic T-lymphocyte preservation.

Effects of Hydrogen in Prevention of Corneal Endothelial Damage During Phacoemulsification: A Prospective Randomized Clinical Trial.

PURPOSE: Hydrogen (H2) has been reported to scavenge free radicals, particularly the hydroxyl radical (·OH). Ultrasound oscillation in an aqueous solution produces ·OH. Our recent study demonstrated that H2 dissolved in an irrigation solution prevented corneal endothelial damage during phacoemulsification in an animal model. We examined the effects of H2 during clinical phacoemulsification. DESIGN: A single-center, prospective, randomized, double-masked clinical trial. METHODS: Thirty-two patients who had cataracts of similar nucleus hardness in both eyes (age: 75.4±7.68 years; 17 males, 15 females) were recruited. Phacoemulsification was performed using a solution of dissolved H2 in one eye, and a conventional solution in the contralateral eye. Endothelial cell density (ECD) at the center of the cornea was measured using noncontact specular microscopy preoperatively and at 1 day, 1 week, and 3 weeks postoperatively. RESULTS: Reduction rates of ECD (mean ± standard deviation) were 16.0%±15.7% at 1 day, 15.4%±16.1% at 1 week, and 18.4%±14.9% at 3 weeks in the control group, compared to 6.5%±8.7% at 1 day (P = .003), 9.3%±11.0% at 1 week (P = .039), and 8.5%±10.5% at 3 weeks (P = .004) in the H2 groups. These rates were significantly smaller in the H2 group at all time points. CONCLUSIONS: H2 dissolved in irrigation solution reduced corneal endothelial damage during phacoemulsification. This suggests that a considerable part of the corneal endothelial damage during phacoemulsification is caused by oxidative stress, and that H2 is useful in clinical phacoemulsification.

Pathologic glomerular characteristics and glomerular basement membrane alterations in biopsy-proven thin basement membrane nephropathy.

BACKGROUND: Thin basement membrane nephropathy (TBMN) is diagnosed by diffuse thinning of the glomerular basement membrane (GBM) without any clinical and pathologic findings of Alport syndrome and the other renal diseases. TBMN is characterized clinically by benign familial hematuria but rarely develops into end-stage renal disease. METHODS: In 27 cases of biopsy-proven TBMN, we evaluated the pathologic characteristics of TBMN, and examined the correlation between these pathologic characterizations and renal dysfunction. RESULTS: All patients had hematuria, and 21 patients (77.8%) had proteinuria. In six patients (28.6%) who were more than 50 years of age, the estimated glomerular filtration rate (eGFR) decreased from G3a to G4 in the chronic kidney disease stage. Pathologically, an irregular decrease in intensity of type IV collagen α5(IV) chain was seen in GBM, and irregular thinning with diffuse rough etched images was observed on the GBM surface with several sizes of holes by low-vacuum scanning electron microscopy. The glomerular morphology of TBMN was characterized by an increased number of small glomerular capillaries with an increased extracellular matrix (ECM). These characteristic morphologic alterations were evident from a young age in patients with TBMN, but were not correlated directly with the decrease of eGFR, the degree of hematuria, and proteinuria. The decrease of eGFR in patients with TBMN who were more than 50 years of age might be primarily mediated by arteriolosclerosis-associated glomerulosclerosis and interstitial fibrosis. CONCLUSION: Characteristic pathological glomerular findings and GBM alterations occurred from a young age but were not associated directly with renal impairment in biopsy-proven TBMN.

Detection of Splicing Abnormalities and Genotype-Phenotype Correlation in X-linked Alport Syndrome.

BACKGROUND: X-linked Alport syndrome (XLAS) is a progressive hereditary nephropathy caused by mutations in the COL4A5 gene. Genotype-phenotype correlation in male XLAS is relatively well established; relative to truncating mutations, nontruncating mutations exhibit milder phenotypes. However, transcript comparison between XLAS cases with splicing abnormalities that result in a premature stop codon and those with nontruncating splicing abnormalities has not been reported, mainly because transcript analysis is not routinely conducted in patients with XLAS. METHODS: We examined transcript expression for all patients with suspected splicing abnormalities who were treated at one hospital between January of 2006 and July of 2017. Additionally, we recruited 46 males from 29 families with splicing abnormalities to examine genotype-phenotype correlation in patients with truncating (n=21, from 14 families) and nontruncating (n=25, from 15 families) mutations at the transcript level. RESULTS: We detected 41 XLAS families with abnormal splicing patterns and described novel XLAS atypical splicing patterns (n=14) other than exon skipping caused by point mutations in the splice consensus sequence. The median age for developing ESRD was 20 years (95% confidence interval, 14 to 23 years) among patients with truncating mutations and 29 years (95% confidence interval, 25 to 40 years) among patients with nontruncating mutations (P=0.001). CONCLUSIONS: We report unpredictable atypical splicing in the COL4A5 gene in male patients with XLAS and reveal that renal prognosis differs significantly for patients with truncating versus nontruncating splicing abnormalities. Our results suggest that splicing modulation should be explored as a therapy for XLAS with truncating mutations.

Clinically diverse phenotypes and genotypes of patients with branchio-oto-renal syndrome.

Branchio-oto-renal (BOR) syndrome is a rare autosomal dominant disorder characterized by branchiogenic anomalies, hearing loss, and renal anomalies. The aim of this study was to reveal the clinical phenotypes and their causative genes in Japanese BOR patients. Patients clinically diagnosed with BOR syndrome were analyzed by direct sequencing, multiplex ligation-dependent probe amplification (MLPA), array-based comparative genomic hybridization (aCGH), and next-generation sequencing (NGS). We identified the causative genes in 38/51 patients from 26/36 families; EYA1 aberrations were identified in 22 families, SALL1 mutations were identified in two families, and SIX1 mutations and a 22q partial tetrasomy were identified in one family each. All patients identified with causative genes suffered from hearing loss. Second branchial arch anomalies, including a cervical fistula or cyst, preauricular pits, and renal anomalies, were frequently identified (>60%) in patients with EYA1 aberrations. Renal hypodysplasia or unknown-cause renal insufficiency was identified in more than half of patients with EYA1 aberrations. Even within the same family, renal phenotypes often varied substantially. In addition to direct sequencing, MLPA and NGS were useful for the genetic analysis of BOR patients.