Genotype-Phenotype Correlation Analysis of WT1 Gene Variants in Denys-Drash Syndrome and Frasier Syndrome / 罕见病研究

ObjectiveThis study aims to explore the association between different genotypes of WT1 gene variations and the phenotypes of Denys-Drash syndrome (DDS) and Frasier syndrome (FS).MethodsThrough searching and summarizing the case information of WT1 gene variations recorded in NCBI PubMed and CNKI databases from January 1, 1991 to October 31, 2023, we analyzed the association between variation types, occurrence locations, and phenotypes such as progressive renal function impairment, genitourinary developmental abnormalities, nephroblastoma, and gonadal tumors between DDS and FS.ResultsA total of 128 articles, including 304 subjects, were included in this study, and 86 pathogenic variations of the WT1 gene were detected.The distribution characteristics of these variations were as follows: the most common occurrence was in exon 9(24/86, 27.9%) and exon 8 (23/86, 26.7%); the most common variation type was missense mutation(51/86, 59.3%), followed by splice site mutation (13/86, 15.1%).The disease types caused by WT1 gene variations were as follows: DDS had the highest number of cases (174/304, 57.2%), followed by FS (83/304, 27.3%); DDS was mainly caused by missense mutations on exon 9 and exon 8 (143/174, 82.2%), while FS was mainly caused by splice site mutations on intron 9 (76/83, 91.6%).ConclusionsThe missense variants in exon 9 and exon 8 on the WT1 gene mainly resulted in DDS, while the splice variants in intron 9 mainly resulted in FS. Infants and children with progressive renal injury should undergo a comprehensive evaluation of the genitourinary system, and early genetic diagnosis should be established to improve prognosis.

High-Throughput Splicing Assays Identify Known and Novel WT1 Exon 9 Variants in Nephrotic Syndrome.

Introduction: Frasier syndrome (FS) is a rare Mendelian form of nephrotic syndrome (NS) caused by variants which disrupt the proper splicing of WT1. This key transcription factor gene is alternatively spliced at exon 9 to produce 2 isoforms ("KTS+" and "KTS-"), which are normally expressed in the kidney at a ∼2:1 (KTS+:KTS-) ratio. FS results from variants that reduce this ratio by disrupting the splice donor of the KTS+ isoform. FS is extremely rare, and it is unclear whether any variants beyond the 8 already known could cause FS. Methods: To prospectively identify other splicing-disruptive variants, we leveraged a massively parallel splicing assay. We tested every possible single nucleotide variant (n = 519) in and around WT1 exon 9 for effects upon exon inclusion and KTS+/- ratio. Results: Splice disruptive variants (SDVs) made up 11% of the tested point variants overall and were tightly concentrated near the canonical acceptor and the KTS+/- alternate donors. Our map successfully identified all 8 known FS or focal segmental glomerulosclerosis (FSGS) variants and 16 additional novel variants which were comparably disruptive to these known pathogenic variants. We also identified 19 variants that, conversely, increased the KTS+/KTS- ratio, of which 2 are observed in unrelated individuals with 46,XX ovotesticular disorder of sex development (46,XX OTDSD). Conclusion: This splicing effect map can serve as functional evidence to guide the clinical interpretation of newly observed variants in and around WT1 exon 9.

Genotype-phenotype correlation of WT1 mutation-related nephropathy in Chinese children.

Introduction: This study aimed to analyze the clinical characteristics of nephropathy associated with WT1 gene mutations in Chinese children and explore the relationship between genotype and clinical phenotype. Methods: Cases diagnosed at the Guangzhou Women and Children's Medical Center, were combined with those retrieved from PubMed and China National Knowledge Infrastructure (CNKI) databases from January 2015 to June 2022 and integrated into a study cohort; grouped according to gene mutation sites, clinical phenotype, and renal pathological types. The clinical characteristics between groups were compared, and the relationship between genotype and age of onset, clinical phenotype, and pathological type were retrospectively analyzed. Results: The center enrolled 15 confirmed children: seven cases of non-simple nephropathy, including Denys-Drash syndrome (DDS) and Frasier syndrome (FS); eight cases of isolated steroid-resistant nephrotic syndrome (ISRNS); and 13 cases (86.7%) that progressed to end-stage renal disease (ESRD). The initial hemoglobin and bicarbonate levels of patients with clinical non-simple nephropathy were significantly lower than those with simple nephropathy, whereas the serum creatinine levels were higher than those of patients with simple nephropathy. A total of 75 cases of nephropathy associated with WT1 mutations in the study cohort met the inclusion and exclusion criteria. The most common clinical manifestations of WT1 mutations in this cohort were DDS (29/75, 38.7%) and ISRNS (37/75, 49.3%). A renal biopsy was performed in 43 patients, and the common types of renal pathology were focal segmental glomerulosclerosis (23/43, 53.5%) and DMS (13/43, 30.2%). Within the cohort, there were 12 cases (16.0%) in the exon 8 mutation group, 32 (42.6%) in the exon 9 group, 19 (25.3%) in the intron 9 group, and 12 (16.0%) in other gene site mutation groups. Common sites of WT1 mutations in Chinese children were exons 9 and intron 9. Exon 8 mutations were uniquely correlated with the age of onset within three months [5/7; 71.4%; Adjusted standardized residual (AR) = 4.2]. The renal survival time in the exon 8 mutation group was the shortest (P = 0.003). Discussion: The molecular and biological characteristics of WT1 mutation-related nephropathy determine the clinical type, pathological features, and renal survival time of the disease; and there was a strong correlation between the genotype and clinical phenotype.

Frasier Syndrome: A 15-Year-Old Phenotypically Female Adolescent Presenting with Delayed Puberty and Nephropathy.

Frasier syndrome (FS) is a rare inherited disorder characterized by gonadal dysgenesis and progressive nephropathy, resulting from mutations in the intron 9 splice donor site of the Wilms tumor 1 (WT1) gene. It is associated with male gonadal dysgenesis (female external genitalia with a 46 XY karyotype), and a high risk of gonadoblastoma during adolescence. Patients with FS present early in childhood with proteinuria that progressively worsens with a high likelihood of end-stage renal disease (ESRD). Herein, we report a 15-year-old female (karyotype 46, XY) patient characterized by delayed puberty and steroid-resistant nephrotic syndrome, in whom whole genome sequencing showed a mutation in intron 9 of the WT1 gene, c.1447 + 4 C>T. This is the first case of FS with delayed puberty as the first complaint with no previous renal symptoms. We consider delayed puberty as an important manifestation of FS and summarize the diagnostic process of delayed puberty in the female phenotype. For clinicians, delayed puberty is a common disorder in pediatrics but requires vigilance for some rare causes. Etiological screening and chromosome karyotype analysis are important for the early diagnosis of FS in patients with delayed puberty.

Síndrome de Frasier: ¿Cómo diagnosticar una enfermedad rara en la consulta de Ginecología? Reporte de caso / Frasier Syndrome: How to diagnose a rare disease in a Gynecology consultation? A case report

Resumen INTRODUCCIÓN: El síndrome de Frasier es una enfermedad de herencia autosómica dominante con una prevalencia inferior a 1 caso por cada millón de recién nacidos vivos. Hasta la fecha se han descrito unos 150 casos. Este síndrome se caracteriza por pseudohermafroditismo masculino, disgenesia gonadal 46, XY y enfermedad glomerular, todo ello producido por una mutación del gen WT1. CASO CLÍNICO: Paciente de 16 años que consultó por amenorrea primaria y ausencia de caracteres sexuales secundarios. Antecedentes: glomerulonefritis focal segmentaria corticorresistente desde la infancia. En la exploración física se objetivó un estadio Tanner 1. Las pruebas complementarias pusieron de manifiesto la ausencia de útero y anejos y un hipogonadismo hipergonadotrópico con cariotipo 46, XY. Ante los hallazgos se decidió la laparoscopia exploradora y salpingooforectomía bilateral. El informe anatomopatológico fue de disgerminoma de ovario derecho. La sospecha clínica se confirmó en el estudio genético, que reportó una mutación del gen WT1, diagnóstica de síndrome de Frasier. En la actualidad, la paciente recibe tratamiento inmunosupresor y hormonal sustitutivo, con una evolución favorable. CONCLUSIÓN: El diagnóstico temprano del síndrome de Frasier es fundamental en virtud del riesgo asociado de malignidad. La baja frecuencia de la enfermedad y la asociación común con retraso puberal en pacientes con enfermedades crónicas puede favorecer el retraso del diagnóstico. El reporte de los casos diagnosticados de este síndrome, y el tratamiento multidisciplinario son decisivos para mejorar el conocimiento de esta rara enfermedad.

Abstract INTRODUCTION: Frasier Syndrome is an autosomal dominant inherited disease with a prevalence of less than 1 per million live births. To date, about 150 cases have been described. This syndrome is characterized by male pseudohermaphroditism, 46, XY gonadal dysgenesis, and glomerular disease, all caused by a mutation of the WT1 gene. It is essential to learn more about this disease, not only because of the high risk of ovarian neoplasia, but also because its early diagnosis will improve the prognosis. CLINICAL CASES: We report the case of a 16-year-old woman who consulted for primary amenorrhea and absence of secondary sexual characteristics. As medical history, she highlighted steroid-resistant focal segmental glomerulonephritis since childhood. The examination revealed Tanner stage 1. Complementary tests revealed the absence of the uterus and adnexa and hypergonadotropic hypogonadism with a 46, XY karyotype. Given the findings, it was decided to perform an exploratory laparoscopy and bilateral salpingo-oophorectomy. The anatomopathological result reported dysgerminoma of the right ovary. The clinical suspicion was confirmed by genetic study, which reported a mutation of the WT1 gene, diagnostic of Frasier Syndrome. Currently, the patient undergoes, along with immunosuppressive treatment, hormone replacement therapy, with a favorable evolution. CONCLUSION: Early diagnosis of Frasier Syndrome is essential given the associated risk of malignancy. The low frequency of the disease and the usual association of delayed puberty in patients with chronic diseases may lead to a diagnostic delay. Therefore, reporting the diagnosed cases of this syndrome, as well as its multidisciplinary management, is essential to improve knowledge about this rare disease.

Congenital diaphragmatic eventration with pulmonary dysplasia in Frasier syndrome due to a WT1 mutation of c.1432+5(IVS9)G>A.

WT1 disorder is caused by a heterozygous variant in the gene WT1 (Wilms' tumor suppressor gene 1), and is clinically diagnosed as Denys-Drash, Meacham, or Frasier syndrome, on a phenotypic continuum that presents as abnormalities of the urogenital system and gonads. Rarely, manifestations appear in the lung, especially in Frasier syndrome. Here we describe the first noted case of congenital diaphragmatic eventration with pulmonary dysplasia in a child with Frasier syndrome. A c.1432+5G > A mutation in intron 9 of WT1 was found. We also summarize pulmonary diseases associated with WT1 mutations in WT1 disorder.

WT1 complete gonadal dysgenesis with membranoproliferative glomerulonephritis: case series and literature review.

BACKGROUND: Intronic WT1 mutations are usually causative of Frasier syndrome with focal segmental glomerulosclerosis as the characteristic nephropathy. Membranoproliferative glomerulonephritis is not commonly associated with disorders of sex development but has been recently identified as a WT1-associated nephropathy, but usually in cases of exonic mutations in either isolated Wilms tumor or Denys-Drash syndrome. METHODS: The clinical and genetic data from 3 individuals are reported. RESULTS: This report describes the kidney manifestations in 3 individuals from 2 unrelated families with Frasier syndrome intronic WT1 mutations, noting that 2 of the 3 individuals have histologically confirmed membranoproliferative glomerulonephritis. CONCLUSIONS: These case reports support expansion of the clinical spectrum of the kidney phenotypes associated with Frasier syndrome providing evidence of an association between WT1 mutation and an immune complex-related membranoproliferative glomerulonephritis. A higher resolution version of the Graphical abstract is available as Supplementary information.

WT1 Pathogenic Variants are Associated with a Broad Spectrum of Differences in Sex Development Phenotypes and Heterogeneous Progression of Renal Disease.

Wilms' tumor suppressor gene 1 (WT1) plays an essential role in urogenital and kidney development. Heterozygous germline pathogenic allelic variants of WT1 have been classically associated with Denys-Drash syndrome (DDS) and Frasier syndrome (FS). Usually, exonic pathogenic missense variants in the zinc finger region are the cause of DDS, whereas pathogenic variants affecting the canonic donor lysine-threonine-serine splice site in intron 9 cause FS. Phenotypic overlap between WT1 disorders has been frequently observed. New WT1 variant-associated phenotypes, such as 46,XX testicular/ovarian-testicular disorders of sex development (DSD) and primary ovarian insufficiency, have been reported. In this report, we describe the phenotypes and genotypes of 7 Brazilian patients with pathogenic WT1 variants. The molecular study involved Sanger sequencing and massively parallel targeted sequencing using a DSD-associated gene panel. Six patients (5 with a 46,XY karyotype and 1 with a 46,XX karyotype) were initially evaluated for atypical genitalia, and a 46,XY patient with normal female genitalia sought medical attention for primary amenorrhea. Germ cell tumors were identified in 2 patients, both with variants affecting alternative splicing of WT1 between exons 9 and 10. Two pathogenic missense WT1 variants were identified in two 46,XY individuals with Wilms' tumors; both patients were <1 year of age at the time of diagnosis. A novel WT1 variant, c.1453_1456 (p.Arg485Glyfs*14), was identified in a 46,XX patient with testicular DSD. Nephrotic proteinuria was diagnosed in all patients, including 3 who underwent renal transplantation after progressing to end-stage kidney disease. The expanding phenotypic spectrum associated with WT1 variants in XY and XX individuals confirms their pivotal role in gonadal and renal development as well as in tumorigenesis, emphasizing the clinical implications of these variants in genetic diagnosis.

Exonic WT1 pathogenic variants in 46,XY DSD associated with gonadoblastoma.

OBJECTIVE: The literature regarding gonadoblastoma risk in exonic Wilms' tumor suppressor gene (WT1) pathogenic variants is sparse. The aim of this study is to describe the phenotypic and genotypic characteristics of Asian-Indian patients with WT1 pathogenic variants and systematically review the literature on association of exonic WT1 pathogenic variants and gonadoblastoma. DESIGN: Combined retrospective-prospective analysis. METHODS: In this study, 46,XY DSD patients with WT1 pathogenic variants detected by clinical exome sequencing from a cohort of 150 index patients and their affected relatives were included. The PubMed database was searched for the literature on gonadoblastoma with exonic WT1 pathogenic variants. RESULTS: The prevalence of WT1 pathogenic variants among 46,XY DSD index patients was 2.7% (4/150). All the four patients had atypical genitalia and cryptorchidism. None of them had Wilms' tumor till the last follow-up, whereas one patient had late-onset nephropathy. 11p13 deletion was present in one patient with aniridia. The family with p.Arg458Gln pathogenic variant had varied phenotypic spectrum of Frasier syndrome; two siblings had gonadoblastoma, one of them had growing teratoma syndrome (first to report with WT1). On literature review, of >100 exonic point pathogenic variants, only eight variants (p.Arg462Trp, p.Tyr177*, p.Arg434His, p.Met410Arg, p.Gln142*, p.Glu437Lys, p.Arg458*, and p.Arg458Gln) in WT1 were associated with gonadoblastoma in a total of 15 cases (including our two cases). CONCLUSIONS: WT1 alterations account for 3% of 46,XY DSD patients in our cohort. 46,XY DSD patients harboring exonic WT1 pathogenic variants carry a small but definitive risk of gonadoblastoma; hence, these patients require a gonadoblastoma surveillance with a more stringent surveillance in those harboring a gonadoblastoma-associated variant.

Systematic Review of Genotype-Phenotype Correlations in Frasier Syndrome.

INTRODUCTION: Frasier syndrome (FS) is a rare inherited kidney disease caused by intron 9 splicing variants of WT1. For wild-type WT1, 2 active splice donor sites in intron 9 cause a mixture of 2 essential transcripts (with or without lysine-threonine-serine [+/KTS or -KTS]), and imbalance of the +KTS/-KTS ratio results in the development of FS. To date, 6 causative intron 9 variants have been identified; however, detailed transcript analysis has not yet been conducted and the genotype-phenotype correlation also remains to be elucidated. METHODS: We conducted an in vitro minigene splicing assay for 6 reported causative variants and in vivo RNA sequencing to determine the +KTS/-KTS ratio using patients' samples. We also performed a systematic review of reported FS cases with a description of the renal phenotype. RESULTS: The in vitro assay revealed that although all mutant alleles produced -KTS transcripts only, the wild-type allele produced both +KTS and -KTS transcripts at a 1:1 ratio. In vivo RNA sequencing showed that patients' samples with all heterozygous variants produced similar ratios of +KTS to -KTS (1:3.2-1:3.5) and wild-type kidney showed almost a 1:1 ratio (1:0.85). A systematic review of 126 cases clarified that the median age of developing ESKD was 16 years in all FS patients, and there were no statistically significant differences between the genotypes or sex chromosome karyotypes in terms of the renal survival period. CONCLUSION: Our study suggested no differences in splicing pattern or renal survival period among reported intron 9 variants causative of FS.

Suspicion of Frasier's Syndrome in the Nephrology Unit of the State University Hospital of Haiti: Case Study and Review of Literature.

OBJECTIVE: Frasier syndrome is a rare genetic nephropathy characterized by the presence of progressive glomerulopathy with proteinuria associated with male pseudo hermaphroditism. This case study described a picture of a young boy where the clinical suspicion context reminded the Frasier syndrome. To our knowledge, this case is the first described in Haiti. CASE STUDY: This is a 19-year-old young phenotypically male, born with a genital anomaly, was seen on referral at the nephrology/dialysis unit of the internal medicine department of the State University Hospital of Haiti for evaluation and follow-up. Insidious progression of symptoms had occurred over 3 years. Over three months of outpatient follow-up, he had four sets of renal labs drawn, and all showed impaired renal function. At the ultrasound, a bilateral cryptorchidism is described in the inguinal, and presence of functional ovaries with follicles of variable size scattered in the parenchyma. So, in the light of these anamnestic, clinical and paraclinical findings, we concluded to the diagnosis of end-stage renal failure by progressive glomerulopathy in a context of Frasier's syndrome. CONCLUSION: With any clinical picture consisting of genital anomalies at birth, renal symptomatology during childhood and the diagnosis of renal failure during adolescence, rare genetic nephropathies, such as Frasier syndrome must be considered.

Frasier Syndrome: A Rare Cause of Refractory Steroid-Resistant Nephrotic Syndrome.

Frasier syndrome is a rare disease that affects the kidneys and genitalia. Patients who have Frasier syndrome develop nephrotic syndrome (NS) featuring focal segmental glomerulosclerosis (FSGS) that is resistant to steroid treatment in early childhood. Male patients can have female external genitalia (pseudo-hermaphroditism) at birth and develop gonado-blastoma in their adolescence. Frasier syndrome is caused by mutations in the splice donor site at intron 9 of the Wilms' tumor WT1 gene; these mutations result in an imbalanced ratio of WT1 protein isoforms and affect the development of the urogenital tract, podocyte function, and tumor suppression. Here, we report on a patient with long-term refractory NS who developed a malignant mixed germ cell tumor arising in a gonado-blastoma of the ovary 8 years after the onset of proteinuria.

A Unique Presentation of XY Gonadal Dysgenesis in Frasier Syndrome due to WT1 Mutation and a Literature Review.

Frasier syndrome (FS), a rare disease caused by inherited or de novo mutation in Wilm's Tumor suppressor gene 1 (WT1), is characterized by slow progressive nephropathy, XY gonadal dysgenesis (XY-DSD), and increased risk for gonadal tumors. Early childhood (1-6 years) nephropathy progresses with age to refractory nephrotic syndrome, and end-stage renal failure in late adolescence, when delayed puberty and/or primary amenorrhea are clinically evident. We report a unique case of FS presenting initially with primary amenorrhea at 16 years, without previous or concomitant renal damage. Only subsequently she developed an extremely late-onset nephropathy. Genetic analysis revealed the IVS9 + 5 G>A mutation in intron 9 of the WT1 gene. This clinical presentation and review of WT1 literature highlights the importance of considering FS in the differential diagnosis of patients with 46,XY disorders of Sexual development, even without nephropathy. Furthermore, the identification WT1 gene mutation prior to evident renal dysfunction indicates an immediate and close surveillance of renal function enabling an optimal and timely medical response.

Immune-complex glomerulonephritis with a membranoproliferative pattern in Frasier syndrome: a case report and review of the literature.

BACKGROUND: Mutations in the Wilms tumor 1 gene cause a spectrum of podocytopathy ranging from diffuse mesangial sclerosis to focal segmental glomerulosclerosis. In a considerable fraction of patients with Wilms tumor 1 mutations, the distinctive histology of immune-complex-type glomerulonephritis has been reported. However, the clinical relevance and etiologic mechanisms remain unknown. CASE PRESENTATION: A 5-year-old child presented with steroid-resistant nephrotic range proteinuria. Initial renal biopsy revealed predominant diffuse mesangial proliferation with a double-contour and coexisting milder changes of focal segmental glomerulosclerosis. Immunofluorescence and electron microscopy revealed a full-house-pattern deposition of immune complexes in the subendothelial and paramesangial areas. Serial biopsies at 6 and 8 years of age revealed that more remarkable changes of focal segmental glomerulosclerosis had developed on top of the initial proliferative glomerulonephritis. Identification of a de novo Wilms tumor 1 splice donor-site mutation in intron 9 (NM_024426.6:c.1447 + 4C > T) and 46,XY-gonadal dysgenesis led to the diagnosis of Frasier syndrome. CONCLUSIONS: Our findings, together with those of others, point to the importance of heterogeneity in clinicopathological phenotypes caused by Wilms tumor 1 mutations and suggest that immune-complex-mediated membranoproliferative glomerulopathy should be considered as a histological variant.

Síndrome de Frasier en una adolescente: asociación con disgenesia gonadal y enfermedad renal crónica / Frasier Syndrome in an adolescent: association to gonadal dysgenesis and renal chronic disease

Se describe el caso clínico de una adolescente de 16 años de edad, con aparente buen estado de salud, quien había sido atendida desde hacía 3 años aproximadamente en la consulta de Pediatría por presentar falta de desarrollo puberal, amenorrea primaria, así como aumento de volumen en miembros inferiores. Se le realizaron los exámenes complementarios pertinentes y dado el conjunto de elementos clínicos que presentaba, incluida una proteinuria significativa asociada a dismorfismos corporales e hipogenitalismo, se consultó el caso con un equipo multidisciplinario, integrado por nefrólogos, endocrinólogos, genetistas y psicólogos. Se le diagnosticó el síndrome de Frasier, como una asociación síndrome nefrótico-disgenesia gonadal.

The case report of a 16 years adolescent with apparent good health state who had been attended approximately for 3 years in the Pediatrics service to present lack of puberal changes, primary amenorrhoea, as well as increase of volume in lower members is described. The pertinent and complementary examinations were carried out and taking into account the group of clinical elements she presented, including a significant proteinuria associated with corporal dysmorfisms and hypogenitalism, the case was exposed to a multidisciplinary team, formed by nephrologists, Endocrinology specialists, geneticists and psychologists. Frasier syndrome was diagnosed, associated to nephrotic syndrome and gonadal dysgenesis.

Síndrome de Frasier, primer caso reportado en Perú: first reported case in Peru / Frasier´s syndrome: first reported case in Peru

El síndrome de Frasier es una enfermedad rara producida por la mutación del gen WT1, caracterizado por pseudohermafroditismo masculino, disgenesia gonadal 46XY y enfermedad glomerular. Reportamos el caso de una mujer de 18 años, diagnosticada a los 12 años de síndrome nefrótico con desarrollo precoz de enfermedad renal crónica terminal y requerimiento de diálisis. A los 17 años se le detectó una tumoración abdominal. La laparotomía exploratoria reveló tumoración anexada a la trompa derecha que se extendía hasta la pared posterior del útero. Se le realizó histerectomía abdominal total con salpingo-ooforectomía bilateral. El diagnóstico anátomo-patológico fue disgerminoma. La paciente tenía amenorrea primaria y ausencia de caracteres sexuales secundarios. El estudio de corpúsculo de Barr de células de mucosa bucal fue negativo para cromatina sexual y el cariotipo fue 46, XY (Disgenesia Gonadal). El estudio genético reportó mutación heterocigótica en el intrón 9 del gen WT1. El cuadro es compatible con síndrome de Frasier, primer caso reportado en Perú. (AU)

Frasier´s syndrome is a rare disease caused by a mutation in the WT1 gene and is characterized by male pseudo hermaphroditism, gonadal dysgenesis 46XY and glomerular disease. We report the case of an 18-year-old female patient diagnosed at the age of 12 years of age of nephrotic syndrome who rapidly progressed to chronic failure needing dialysis. At the age of 17-years of age she presented an abdominal tumor, a laparotomy revealed a tumor attached to the right fallopian tube. An hysterectomy with bilateral fallopian tube extirpation, pathological findings revealed a dysgerminoma. The patient had a history of primary amenorrhea and absence of secondary sexual features. The study of Barr´s corpuscle of the oral mucosa was negative for sexual chromatin and the karyotype was 46 XY (gonadal dysgenesis). The genetic study revealed heterozygous mutation in the 9 gene WT1. The clinical presentation is compatible with Frasier´s syndrome, fist time reported in Peru. (AU)

Once-Daily Low-Dose Cyclosporine A Treatment with Angiotensin Blockade for Long-Term Remission of Nephropathy in Frasier Syndrome.

Cyclosporine A is known to be effective in some genetic podocyte injury. However, the efficacy of cyclosporine A depends on the degree of histopathological findings, and the relationship between long-term use and renal prognosis remains unknown. Frasier syndrome is a rare genetic disorder caused by intronic mutations in WT1, and is characterized by progressive glomerulopathy, a 46,XY disorder of sex development, and an increased risk of gonadoblastoma. We report here a 16-year-old phenotypically female patient with Frasier syndrome. A renal biopsy at the age of seven years showed segmentally effaced podocyte foot processes with no evidence of glomerulosclerosis. Steroid-resistant proteinuria progressed to the nephrotic range at the age of 10 years, which responded to once-daily administration of cyclosporine A with low two-hour post-dose cyclosporine A (C2) levels; she then achieved stable partial remission in combination with renin-angiotensin system (RAS) blockade. At the age of 12 years, examinations for delayed puberty confirmed the diagnosis of Frasier syndrome. The second renal biopsy showed widespread foot process effacement and a minor lesion of segmental glomerulosclerosis without findings suggestive of cyclosporine A nephropathy. She maintained partial remission and normal renal function with the continuation of once-daily low-dose cyclosporine A. The C2 levels required for the remission were between 212 and 520 ng/ml. Cyclosporine A dosages sufficient for maintaining the C2 levels were 1.1-1.2 mg/kg per day. In conclusion, the long-lasting treatment of once-daily low-dose cyclosporine A with RAS inhibition was effective for induction and maintenance of partial remission in Frasier syndrome.

Clinical heterogeneity in children with gonadal dysgenesis associated with non-mosaic 46,XY karyotype.

INTRODUCTION: Gonadal dysgenesis is unique in disorders of sex development (DSD), in that it can be associated with 46,XX, 46,XY or mosaic 45,X/46,XY karyotypes. Gonadal dysgenesis can be partial or complete. Gonadal dysgenesis associated with the Y-chromosome has increased risk of gonadal germ cell neoplasms. Most of the literature focus on 45,X/46,XY gonadal dysgenesis, while there are scanty data on the condition when the karyotype is non-mosaic 46,XY. OBJECTIVE: To investigate the diversity of clinical pictures of children presenting with 46,XY DSD due to gonadal dysgenesis. METHODS: A retrospective study on consecutive patients diagnosed with 46,XY gonadal dysgenesis at age ≤18 years in a tertiary center from 1985 to 2015. The clinical presentations, phenotypes, gonadal features and associated anomalies were investigated. RESULTS: Twenty-eight patients with Y-chromosome gonadal dysgenesis were identified during the study period and six (21.4%) had non-mosaic 46,XY karyotype. Three had complete gonadal dysgenesis (CGD) with normal female phenotype, while the other three had partial gonadal dysgenesis (PGD). Of the three patients with CGD, two presented with the classical Swyer syndrome at adolescence, while the third presented at birth with multiple congenital anomalies. The three PGD patients presented with ambiguous genitalia at birth (n = 2), and isolated hypospadias (n = 1), which was associated with Frasier syndrome. Three patients had germ cell neoplasms: bilateral gonadoblastoma (n = 1), bilateral intratubular germ cell neoplasia unclassified (n = 1), and dysgerminoma + gonadoblastoma (n = 1). Two patients had global developmental delay with other congenital anomalies, and another patient had learning difficulties with borderline intelligence (Table). DISCUSSION: The findings suggest that 46,XY gonadal dysgenesis is much rarer than 45,X/46,XY gonadal dysgenesis. Patients differed in their clinical presentations and well-established syndromes happened in half of them. Overall, the risk of germ cell neoplasms and the association with other somatic anomalies appeared to be high. The study was limited by: its small number, single-center experience, and the possibility of missing the diagnosis in some male patients with mild undervirilization. CONCLUSION: Heterogeneity was noted in the clinical, phenotypic and gonadal features among pediatric patients with 46,XY gonadal dysgenesis.