A novel T cell-redirecting anti-GPRC5D × CD3 bispecific antibody with potent antitumor activity in multiple myeloma preclinical models.

G-protein-coupled receptor class 5 member D (GPRC5D) is detected in malignant plasma cells in approximately 90% of patients diagnosed with multiple myeloma (MM). Here, we constructed BsAb5003, a novel humanized bispecific monoclonal antibody targeting CD3 and GPRC5D, and evaluated its therapeutic impact on MM. BsAb5003 induced specific cytotoxicity of GPRC5D-positive MM cells with concomitant T cell activation and cytokine release. The efficacy of BsAb5003 was associated with GPRC5D expression levels in MM cell lines. Flow cytometry analysis of bone marrow mononuclear cells (BMMNCs) from 49 MM patients revealed that GPRC5D was expressed in a wide population of MM patients, including heavily treated and high-risk patients. In ex vivo assays using BMMNCs, BsAb5003 induced potent efficacy against CD138 + MM cells in both newly diagnosed and relapsed/refractory patient samples in a GPRC5D expression-dependent manner. BsAb5003 significantly enhanced T cell activation and cytokine production in combination with immunomodulatory drugs (IMiDs) against MM cell lines. BsAb5003 also demonstrated significant inhibition of in vivo tumor growth by recruiting T cells. Taken together, these results suggest that T cell-redirecting bispecific antibody targeting GPRC5D as monotherapy and combination therapy with IMiDs could be a highly potent and effective treatment approach for a wide population of MM patients.

Incidence and Risk factors of Intraocular Inflammation after Brolucizumab Treatment in Japan: A Multicenter AMD Study.

PURPOSE: To investigate the incidence of intraocular inflammation (IOI) and its risk factors following intravitreal injections of brolucizumab for neovascular age-related macular degeneration (nAMD) in Japan. METHODS: A total of 1351 Japanese consecutive patients with nAMD who were treated with brolucizumab from May 2020 to May 2022 at 14 institutions were examined. The variables analyzed were the number of brolucizumab injections, time to onset of IOI, and risk factors. RESULTS: IOI developed in 152 eyes (11.3%). Retinal vasculitis and/or retinal occlusion (RV and/or RO) occurred in 53 eyes (3.9%). Ninety-four patients received bilaterally, bilateral IOI occurred in 5 patients (5.3%). Sixteen eyes (1.2%) had irreversible visual acuity loss and nine eyes (0.67%) had visual loss of 3 lines or more due to RV and/or RO. The cumulative IOI incidence was 4.5%, 10.3%, and 12.2% at 30, 180, and 365 days (1-year), respectively. Prior history of IOI (including RV) and/or RO (odds ratio[OR], 5.41; P = 0.0075) and female sex (OR, 1.99; P = 0.0004) were significantly associated with IOI onset. CONCLUSION: The 1-year cumulative incidence of IOI in Japanese nAMD patients treated with brolucizumab was 12.2%. Prior history of IOI (including RV) and/or RO and female sex were significant risk factors.

Six-month outcomes of switching from aflibercept to faricimab in refractory cases of neovascular age-related macular degeneration.

PURPOSE: To assess 6-month outcomes of switching from aflibercept to faricimab in eyes with refractory neovascular age-related macular degeneration (nAMD) previously requiring monthly injections. METHODS: This multicenter retrospective study examined nAMD eyes receiving monthly aflibercept injections switched to faricimab administered monthly up to 4 injections followed by injections at a minimum of 2-month intervals as per drug labeling. Data regarding age, sex, number of previous injections, treatment intervals, and best-corrected visual acuity (BCVA) were collected. Central retinal thickness (CRT), subfoveal choroidal thickness (SFCT), and maximal pigment epithelial detachment (PED) height were measured by optical coherence tomography. RESULTS: The study included 130 eyes of 124 patients. At 6 months, 53 eyes (40.8%) continued on faricimab treatment (Group 1), while 77 eyes (59.2%) discontinued faricimab for various reasons (Group 2) the most common being worse exudation. There were no significant differences between the two groups at baseline. In Group 1, CRT and SFCT significantly decreased at 1 month (P = 0.013 and 0.008), although statistical significance was lost at 6 months (P = 0.689 and 0.052). BCVA and maximal PED height showed no significant changes; however, mean treatment intervals were extended from 4.4 ± 0.5 weeks at baseline to 8.7 ± 1.7 weeks at 6 months (P < 0.001) in Group 1. No clear predictors of response were identified. CONCLUSION: Switching from aflibercept to faricimab allowed for extension of treatment intervals from monthly to bimonthly in roughly 40% of eyes, suggesting that faricimab may be considered in refractory nAMD cases.

An Infant Case of Transient Distal Renal Tubular Acidosis and Fanconi Syndrome Caused by Rotavirus Gastroenteritis.

We report an infant case of transient distal renal tubular acidosis and Fanconi syndrome caused by rotavirus gastroenteritis. A 10-month-old boy was admitted to the hospital because of frequent vomiting, lack of vitality, and dehydration. He was diagnosed with rotavirus gastroenteritis on account of his positive stool rotavirus antigen test. Although he presented with acidemia and severe mixed metabolic acidosis, he also had a urine pH of 6.0, indicating impaired urinary acidification. Therefore, he was diagnosed with distal renal tubular acidosis. On the third day of hospitalization, a relatively low %tubular reabsorption of phosphate level with hypophosphatemia, increased fractional excretion of uric acid with hypouricemia, and high urinary ß2-microglobulin levels were observed. Moreover, he was diagnosed with Fanconi syndrome on account of multiple proximal tubular dysfunctions. After remission of rotavirus gastroenteritis, the signs of renal tubular dysfunction improved. This was a case of rotavirus gastroenteritis-caused transient distal renal tubular acidosis and Fanconi syndrome. Severe metabolic acidosis resulted from anion-gap metabolic acidosis due to acute kidney injury by rotavirus gastroenteritis and normal anion-gap acidosis due to renal tubular acidosis. When renal tubular acidosis is associated with a disease that causes anion-gap metabolic acidosis, mixed metabolic acidosis occurs and becomes exacerbated. Furthermore, it is important to consider the complications of renal tubular acidosis in the case of severe metabolic acidosis.

Prioritization of Monogenic Congenital Anomalies of the Kidney and Urinary Tract Candidate Genes with Existing Single-Cell Transcriptomics Data of the Human Fetal Kidney.

INTRODUCTION: Congenital anomalies of the kidney and urinary tract (CAKUT) are the most common cause of chronic kidney disease in the first 3 decades of life. Over 40 genes have been identified as causative for isolated human CAKUT. However, many genes remain unknown, and the prioritization of potential CAKUT candidate genes is challenging. To develop an independent approach to prioritize CAKUT candidate genes, we hypothesized that monogenic CAKUT genes are most likely co-expressed along a temporal axis during kidney development and that genes with coinciding high expression may represent strong novel CAKUT candidate genes. METHODS: We analyzed single-cell mRNA (sc-mRNA) transcriptomics data of human fetal kidney for temporal sc-mRNA co-expression of 40 known CAKUT genes. A maximum of high expression in consecutive timepoints of kidney development was found for four of the 40 genes (EYA1, SIX1, SIX2, and ITGA8) in nephron progenitor cells a, b, c, d (NPCa-d). We concluded that NPCa-d are relevant for CAKUT pathogenesis and intersected two lists of CAKUT candidate genes resulting from unbiased whole-exome sequencing (WES) with the 100 highest expressed genes in NPCa-d. RESULTS: Intersection of the 100 highest expressed genes in NPCa-d with WES-derived CAKUT candidate genes identified an overlap with the candidate genes KIF19, TRIM36, USP35, CHTF18, in each of which a biallelic variant was detected in different families with CAKUT. CONCLUSION: Sc-mRNA expression data of human fetal kidney can be utilized to prioritize WES-derived CAKUT candidate genes. KIF19, TRIM36, USP35, and CHTF18 may represent strong novel candidate genes for CAKUT.

Three-month outcomes of faricimab loading therapy for wet age-related macular degeneration in Japan.

This multicenter study aimed to assess the short-term effectiveness and safety of faricimab in treatment-naïve patients with wet age-related macular degeneration (wAMD) in Japan. We retrospectively reviewed 63 eyes of 61 patients with wAMD, including types 1, 2, and 3 macular neovascularization as well as polypoidal choroidal vasculopathy (PCV). Patients received three consecutive monthly intravitreal injections of faricimab as loading therapy. Over these 3 months, visual acuity improved gradually compared to baseline. Moreover, the central foveal thickness decreased significantly at 1, 2, and 3 months compared to baseline (p < 0.0001). At 3 months after initiation of faricimab therapy, a dry macula (defined as absence of intraretinal or subretinal fluid) was achieved in 82% of the eyes. Complete regression of polypoidal lesions was observed in 52% of eyes with PCV. Subfoveal choroidal thickness also decreased significantly at 1, 2, and 3 months compared to baseline (p < 0.0001). Although retinal pigment epithelium tears developed in two eyes, there were no other ocular or systemic complications observed during the 3 months of loading therapy. In conclusion, loading therapy using faricimab resulted in improved visual acuity and retinal morphology in Japanese patients with wAMD without particular safety issues.

Recessive CHRM5 variant as a potential cause of neurogenic bladder.

Neurogenic bladder is caused by disruption of neuronal pathways regulating bladder relaxation and contraction. In severe cases, neurogenic bladder can lead to vesicoureteral reflux, hydroureter, and chronic kidney disease. These complications overlap with manifestations of congenital anomalies of the kidney and urinary tract (CAKUT). To identify novel monogenic causes of neurogenic bladder, we applied exome sequencing (ES) to our cohort of families with CAKUT. By ES, we have identified a homozygous missense variant (p.Gln184Arg) in CHRM5 (cholinergic receptor, muscarinic, 5) in a patient with neurogenic bladder and secondary complications of CAKUT. CHRM5 codes for a seven transmembrane-spanning G-protein-coupled muscarinic acetylcholine receptor. CHRM5 is shown to be expressed in murine and human bladder walls and is reported to cause bladder overactivity in Chrm5 knockout mice. We investigated CHRM5 as a potential novel candidate gene for neurogenic bladder with secondary complications of CAKUT. CHRM5 is similar to the cholinergic bladder neuron receptor CHRNA3, which Mann et al. published as the first monogenic cause of neurogenic bladder. However, functional in vitro studies did not reveal evidence to strengthen the status as a candidate gene. Discovering additional families with CHRM5 variants could help to further assess the genes' candidate status.

Automated Quantitative Analysis of Anterior Segment Inflammation Using Swept-Source Anterior Segment Optical Coherence Tomography: A Pilot Study.

Background: The aim of this study is to develop an automated evaluation of anterior chamber (AC) cells in uveitis using anterior segment (AS) optical coherence tomography (OCT) images. Methods: We analyzed AS swept-source (SS)-OCT (CASIA 2) images of 31 patients (51 eyes) with uveitis using image analysis software (Python). An automated algorithm was developed to detect cellular spots corresponding to hyper-reflective spots in the AC, and the correlation with Standardization of Uveitis Nomenclature (SUN) grading AC cells score was evaluated. The approximated AC grading value was calculated based on the logarithmic approximation curve between the number of cellular spots and the SUN grading score. Results: Among 51 eyes, cellular spots were automatically segmented in 48 eyes, whereas three eyes (all SUN grading AC cells score: 4+) with severe fibrin formation in the AC were removed by the automated algorithm. The AC cellular spots increased with an increasing SUN grading score (p < 0.001). The 48 eyes were split into training data (26 eyes) and test data (22 eyes). There was a significant correlation between the SUN grading score and the number of cellular spots in 26 eyes (rho: 0.843, p < 0.001). There was a significant correlation between the SUN grading score and the approximated grading value of 22 eyes based on the logarithmic approximation curve (rho: 0.774, p < 0.001). Leave-one-out cross-validation analysis demonstrated a significant correlation between the SUN grading score and the approximated grading value of 48 eyes (rho: 0.748, p < 0.001). Conclusions: This automated anterior AC cell analysis using AS SS-OCT showed a significant correlation with clinical SUN grading scores and provided SUN AC grading values as a continuous variable. Our findings suggest that automated grading of AC cells could improve the accuracy of a quantitative assessment of AC inflammation using AS-OCT images and allow the objective and rapid evaluation of anterior segment inflammation in uveitis. Further investigations on a large scale are required to validate this quantitative measurement of anterior segment inflammation in uveitic eyes.

Genetic Ablation of Nrf2 Exacerbates Neuroinflammation in Ocular Autoimmunity.

Experimental autoimmune uveoretinitis (EAU) is an animal model of non-infectious uveitis and is developed by immunization with retinal antigen, interphotoreceptor retinoid-binding protein (IRBP). Nuclear factor erythroid 2- (NF-E2-) related factor 2 (Nrf2) is responsible for regulating antioxidant and inflammatory responses. In this study, we investigated the role of Nrf2 on the development of EAU. Clinical and pathological examination demonstrated that retinal inflammation was exacerbated in Nrf2 knockout (Nrf2 KO) mice compared to wild type (WT) mice, and the expression of inflammatory cytokines (IFN-γ, IL-6, and IL-17) in the retina was significantly elevated in Nrf2 KO mice. GFAP positive cells (astrocytes) and Iba-1 positive cells (microglia cells) in the retina were more numerous in Nrf2 KO mice compared to WT mice. Furthermore, we examined the suppressive effect of the Nrf2 activator CDDO-Im (2-cyano-3,12 dioxooleana-1,9 dien-28-oyl imidazoline) on the development of EAU. The treatment with CDDO-Im significantly reduced the clinical and pathological score of EAU compared to those of vehicle-treated mice. These findings suggest that Nrf2 plays a regulatory role in the pathogenesis of autoimmune uveoretinitis and the activation of the Nrf2 system may have therapeutic potential for protecting vision from autoimmune neuroinflammation.

Copy Number Variation Analysis Facilitates Identification of Genetic Causation in Patients with Congenital Anomalies of the Kidney and Urinary Tract.

Background: Congenital anomalies of the kidneys and urinary tract (CAKUT) are the most common cause of chronic kidney disease among children and adults younger than 30 yr. In our previous study, whole-exome sequencing (WES) identified a known monogenic cause of isolated or syndromic CAKUT in 13% of families with CAKUT. However, WES has limitations and detection of copy number variations (CNV) is technically challenging, and CNVs causative of CAKUT have previously been detected in up to 16% of cases. Objective: To detect CNVs causing CAKUT in this WES cohort and increase the diagnostic yield. Design setting and participants: We performed a genome-wide single nucleotide polymorphism (SNP)-based CNV analysis on the same CAKUT cohort for whom WES was previously conducted. Outcome measurements and statistical analysis: We evaluated and classified the CNVs using previously published predefined criteria. Results and limitations: In a cohort of 170 CAKUT families, we detected a pathogenic CNV known to cause CAKUT in nine families (5.29%, 9/170). There were no competing variants on genome-wide CNV analysis or WES analysis. In addition, we identified novel likely pathogenic CNVs that may cause a CAKUT phenotype in three of the 170 families (1.76%). Conclusions: CNV analysis in this cohort of 170 CAKUT families previously examined via WES increased the rate of diagnosis of genetic causes of CAKUT from 13% on WES to 18% on WES + CNV analysis combined. We also identified three candidate loci that may potentially cause CAKUT. Patient summary: We conducted a genetics study on families with congenital anomalies of the kidney and urinary tract (CAKUT). We identified gene mutations that can explain CAKUT symptoms in 5.29% of the families, which increased the percentage of genetic causes of CAKUT to 18% from a previous study, so roughly one in five of our patients with CAKUT had a genetic cause. These analyses can help patients with CAKUT and their families in identifying a possible genetic cause.

Comparative Analysis of Serum microRNA in Diagnosed Ocular Sarcoidosis versus Idiopathic Uveitis with Ocular Manifestations of Sarcoidosis.

"Idiopathic" is the most common category of uveitis, representing cases in which a specific diagnosis has not been established despite work-up. Sarcoidosis is a systemic granulomatous disorder affecting multiple organs including the lungs, skin, kidneys, and eyes. We used microRNA (miRNA) microarrays to investigate serum miRNA profiles of patients with ocular sarcoidosis as diagnosed by specific criteria (diagnosed ocular sarcoidosis), and patients with idiopathic uveitis characterized by ocular manifestations of sarcoidosis (suspected ocular sarcoidosis). Principal component analysis (PCA) and hierarchical clustering showed that serum miRNA profiles of diagnosed ocular sarcoidosis and suspected ocular sarcoidosis were both clearly distinguishable from healthy controls. Furthermore, comparative analysis of the miRNA profiles showed highly similar patterns between diagnosed ocular sarcoidosis and suspected ocular sarcoidosis. Pathway analysis revealed common pathways were involved in the two groups, including those of WNT signaling and TGF-beta signaling. Our study demonstrated a high overlap of differentially expressed serum miRNAs in patients with diagnosed ocular sarcoidosis and suspected ocular sarcoidosis, suggesting that these groups share a similar underlying pathology and may represent possible variants of the disease. Characterization of serum miRNA profiles may provide an opportunity for earlier diagnosis and treatment, and may inform more accurate clinical prognosis in patients with an ocular sarcoidosis phenotype.

Clinical features and visual outcomes of ocular sarcoidosis at a tertiary referral center in Tokyo.

BACKGROUND: To analyze clinical features, treatment, complications, and visual outcomes of ocular sarcoidosis at a tertiary center in Tokyo. METHODS: Clinical records of 53 patients with ocular sarcoidosis ("definite" or "presumed") presenting between 2013 and 2018 to the Kyorin Eye Center were retrospectively reviewed. Diagnosis was based on the revised criteria of the International Workshop on Ocular Sarcoidosis. RESULTS: Definite (biopsy-proven) disease was present in 87% of patients and presumed disease in 13%. The mean age at presentation was 58 years (13-81 years) and 68% were women. The mean follow-up was 34 months (6-70 months). Forty-five patients (85%) had panuveitis, and the most common ocular clinical sign suggestive of ocular sarcoidosis was bilaterality (92%). Ocular complications were observed in 93 eyes (85%), most commonly cataract (73%), epiretinal membrane (24%), macular edema (24%) and glaucoma (19%). Thirty-one eyes (30%) underwent cataract surgery and 12 eyes (12%) underwent pars plana vitrectomy. Ten patients (19%) received systemic corticosteroid therapy and 33 eyes (32%) received periocular corticosteroid injections. The best-corrected visual acuity was 1.0 or better in 51% of eyes at presentation, 57% at 6 months, 50% at 12 months, and 58% at 36 months. CONCLUSIONS: The majority of ocular sarcoidosis patients were women, had bilateral disease and panuveitis involvement. Most eyes maintained good visual acuity, although surgical interventions for cataract and epiretinal membrane were common.

Short-term results for brolucizumab in treatment-naïve neovascular age-related macular degeneration: a Japanese multicenter study.

PURPOSE: To investigate short-term treatment outcomes of intravitreal brolucizumab (IVBr) for treatment-naïve neovascular age-related macular degeneration (AMD) in a Japanese multicenter study. STUDY DESIGN: Retrospective case control study METHODS: The subjects were 58 eyes of 57 patients with neovascular AMD (43 men and 14 women, mean age 74.6 years) of whom 43 eyes of 42 patients completed initial loading of 3 monthly IVBr injections and were followed for more than 3 months. Best-corrected visual acuity (BCVA) changes, anatomical outcomes, and complications were investigated. RESULTS: Of the 43 eyes that completed loading doses, the AMD subtype was type 1 and type 2 macular neovascularization (MNV) in 51%, polypoidal choroidal vasculopathy (PCV) in 42%, and type 3 MNV in 7%. At 3 months after initiating treatment, BCVA significantly improved (P = 0.002) and central retinal thickness significantly decreased (P < 0.0001). At 3 months, complete retinal and subretinal fluid resolution was achieved in 91% of all eyes and complete regression of polypoidal lesions was achieved in 82% of PCV eyes. Iritis occurred in 8 eyes of 8 patients (14%), but resolved using topical or subtenon corticosteroid injection without visual loss in all cases. CONCLUSIONS: IVBr for treatment-naïve neovascular AMD was effective in the short-term, achieving significantly improved BCVA, good retinal fluid resolution, and a high rate of polypoidal lesion regression. However, iritis was noted in 14% of patients which may limit use of this drug.

A COVID-19 Risk Reduction Strategy for the Treatment of Acute Vogt-Koyanagi-Harada Disease Utilizing the Antiviral Potential of Cyclosporine.

PURPOSE: To report on the successful treatment of patients with acute Vogt-Koyanagi-Harada (VKH) disease utilizing the antiviral potential of cyclosporine during the COVID-19 pandemic. STUDY DESIGN: Case series. METHODS: Clinical records were retrospectively reviewed of 4 patients presenting with new-onset acute VKH disease who elected to receive initial treatment consisting of bilateral sub-Tenon injection of triamcinolone acetonide combined with immediately starting oral cyclosporine without the use of systemic corticosteroids. RESULTS: The mean follow-up was 17.0 months. Choroidal thickness decreased to normal with recovery of bilateral best-corrected visual acuity (BCVA) of 1.2 in 3 patients. One elderly patient had decreased BCVA (OD 0.5, OS 0.8) due to cataract progression and mild epiretinal membrane. No recurrences of intraocular were observed in any patients. Mild renal dysfunction developed in 2 elderly patients, but importantly no patients developed COVID-19 disease. CONCLUSIONS: Oral cyclosporine as the initial systemic treatment of acute VKH disease, in combination with sub-Tenon injection of triamcinolone acetonide, lead to favorable clinical outcomes. Due to the known antiviral properties of cyclosporine, we suggest that this may represent a good treatment strategy for patients during the COVID-19 pandemic.

Whole exome sequencing identifies potential candidate genes for spina bifida derived from mouse models.

Spina bifida (SB) is the second most common nonlethal congenital malformation. The existence of monogenic SB mouse models and human monogenic syndromes with SB features indicate that human SB may be caused by monogenic genes. We hypothesized that whole exome sequencing (WES) allows identification of potential candidate genes by (i) generating a list of 136 candidate genes for SB, and (ii) by unbiased exome-wide analysis. We generated a list of 136 potential candidate genes from three categories and evaluated WES data of 50 unrelated SB cases for likely deleterious variants in 136 potential candidate genes, and for potential SB candidate genes exome-wide. We identified 6 likely deleterious variants in 6 of the 136 potential SB candidate genes in 6 of the 50 SB cases, whereof 4 genes were derived from mouse models, 1 gene was derived from human nonsyndromic SB, and 1 gene was derived from candidate genes known to cause human syndromic SB. In addition, by unbiased exome-wide analysis, we identified 12 genes as potential candidates for SB. Identification of these 18 potential candidate genes in larger SB cohorts will help decide which ones can be considered as novel monogenic causes of human SB.

Subfoveal choroidal thickness after brolucizumab therapy for neovascular age-related macular degeneration: a short-term multicenter study.

BACKGROUND/PURPOSE: Observation of choroidal thickness after anti-vascular endothelial growth factor (VEGF) therapy may be important for the ideal management of neovascular age-related macular degeneration (AMD). This study investigated changes in subfoveal choroidal thickness (SCT) during loading doses of intravitreal injections of brolucizumab in eyes with neovascular AMD. METHODS: This study included 73 eyes of 72 patients with neovascular AMD at five university hospitals in Japan. All 73 eyes underwent three monthly 6.0 mg intravitreal injections of brolucizumab at baseline, 1 month, and 2 months. The SCT at 3 months was evaluated using optical coherence tomography. RESULTS: The 73 eyes were classified into the treatment-naïve group (43 eyes) and the switched group (30 eyes) that were switched from other anti-VEGF treatments. After three intravitreal injections of brolucizumab, SCT significantly decreased from 236.5 ± 98.8 µm at baseline to 200.4 ± 98.3 µm at 3 months (percent of baseline 84.7%, P < 0.001) in the treatment-naïve group. In the switched group, SCT also significantly decreased from 229.0 ± 113.2 µm at baseline to 216.9 ± 110.2 µm at 3 months (percent of baseline 94.7%, P = 0.039), although the decrease was not as marked compared to that of the treatment-naïve group. CONCLUSION: Intravitreal injections of brolucizumab for neovascular AMD significantly reduced the SCT in both the treatment-naïve and switched groups. Brolucizumab may cause significant anatomic changes in the choroid, particularly in treatment-naïve AMD eyes, possibly more than that previously reported for other anti-VEGF agents.

Reverse phenotyping facilitates disease allele calling in exome sequencing of patients with CAKUT.

PURPOSE: Congenital anomalies of the kidneys and urinary tract (CAKUT) constitute the leading cause of chronic kidney disease in children. In total, 174 monogenic causes of isolated or syndromic CAKUT are known. However, syndromic features may be overlooked when the initial clinical diagnosis of CAKUT is made. We hypothesized that the yield of a molecular genetic diagnosis by exome sequencing (ES) can be increased by applying reverse phenotyping, by re-examining the case for signs/symptoms of the suspected clinical syndrome that results from the genetic variant detected by ES. METHODS: We conducted ES in an international cohort of 731 unrelated families with CAKUT. We evaluated ES data for variants in 174 genes, in which variants are known to cause isolated or syndromic CAKUT. In cases in which ES suggested a previously unreported syndromic phenotype, we conducted reverse phenotyping. RESULTS: In 83 of 731 (11.4%) families, we detected a likely CAKUT-causing genetic variant consistent with an isolated or syndromic CAKUT phenotype. In 19 of these 83 families (22.9%), reverse phenotyping yielded syndromic clinical findings, thereby strengthening the genotype-phenotype correlation. CONCLUSION: We conclude that employing reverse phenotyping in the evaluation of syndromic CAKUT genes by ES provides an important tool to facilitate molecular genetic diagnostics in CAKUT.