Objective:To explore the clinical feature and genetic variation of NPHS1 variant-associated nephropathy ( NPHS1-VAN) in Chinese patients. Methods:This study was a case-series analysis. Patients with NPHS1-VAN, who were treated and/or followed in the Department of Pediatrics, Nanfang Hospital, Southern Medical University between 2018 and 2023 were recruited into this study. Genotype, phenotype and their relationship were analyzed. Results:Nine NPHS1-VAN patients from 8 non-consanguineous Chinese families were collected, including 5 males and 4 females. There were 7 cases with an onset age within 3 months and 2 cases with an onset age of 6 months and 13 years, respectively. Seven patients harbored compound heterozygous variants, two had homozygous variants, including 8 missense variations,3 frameshift variants, and 1 splicing site variant. Four patients in 3 families harbored missense variant c.928G>A, two of them experienced spontaneous remission of proteinuria at the age of 1 year and 2 years, respectively, another one had persistent proteinuria and entered end stage renal disease (ESRD) at 11 years old. The other one had an onset age of 6 months with no response to steroids initially. She got complete remission by tacrolimus administered, but relapse frequently and partially responded to steroids later. Two patients of this group died, one of them died of respiratory failure 3 days after birth. Excessive amniotic fluid and fetal edema were acknowledged at 28 weeks of gestational age. He harbored compound heterozygous variants of NPHS1, c.1135C>G (R379G) and c.1339G>A (E447K). His mother previously experienced fetal death at 28 weeks gestational age for her first pregnant and stillborn at 36 weeks of gestational age for her second pregnant, respectively. One patient in this study who harbored homozygous variant of c.1339G>A (E447K) presented with a mild phenotype, onset age was 13 years old and didn't progress to ESRD yet at 21 years. Thus, variant E447K was hypothesized to be weakly pathogenic, while R379G may be strongly pathogenic with a risk of death. Five novel variants were identified in this group of patients, 3 missense variants (c.1135C>G, c.1157A>T, c.3197T>A) and 2 frameshift variants (c.709_710delCT, c.3193delG). Renal biopsy was performed in 4 cases, of whom two were focal segmental glomerular sclerosis and another two were minimal change disease. Conclusions:NPHS1-VAN possesses remarkable clinical and genetic heterogeneity. Five novel variants were identified. Missense variant is the most common variant type and c.928G>A is the most common one in this group of patients, in consistent with previous report in China. Children harbor c.928G>A may have a mild phenotype with possible spontaneous remission and may be response to steroids and calcineurin inhibitor. Variant c.1135C>G (R379G) may have a strong pathogenicity, and patient who harbors this variant may have a severe phenotype.

Joubert syndrome is a rare primary ciliopathy characterized by hypoplasia of the midbrain and vermis cerebellum, with or without extracerebral organs involvement. This article reports a case of Joubert syndrome with RPGRIP1L mutation, presented with anemia, renal dysfunction, growth retardation, and mental retardation. The patient reached end-stage renal disease at the age of 13 years old. Magnetic resonance imaging of the brain revealed slight elongation of the superior cerebellar peduncles, mild hypoplasia of the cerebellar vermis, and the characteristic "molar tooth sign". Elevated transaminase and γ-glutamyl transpeptidase levels were detected at the age of 14 years old. Genetic analysis showed a compound heterozygous mutation in the RPGRIP1L gene (c.1290_1291delGT, c.3764T>C). Joubert syndrome is a clinically heterogeneous disorder and easy to be missed. Early diagnosis and standard treatment contribute to a better prognosis.

Objective:To explore the clinical feature and genetic variation of NPHS1 variant-associated nephropathy ( NPHS1-VAN) in Chinese patients. Methods:This study was a case-series analysis. Patients with NPHS1-VAN, who were treated and/or followed in the Department of Pediatrics, Nanfang Hospital, Southern Medical University between 2018 and 2023 were recruited into this study. Genotype, phenotype and their relationship were analyzed. Results:Nine NPHS1-VAN patients from 8 non-consanguineous Chinese families were collected, including 5 males and 4 females. There were 7 cases with an onset age within 3 months and 2 cases with an onset age of 6 months and 13 years, respectively. Seven patients harbored compound heterozygous variants, two had homozygous variants, including 8 missense variations,3 frameshift variants, and 1 splicing site variant. Four patients in 3 families harbored missense variant c.928G>A, two of them experienced spontaneous remission of proteinuria at the age of 1 year and 2 years, respectively, another one had persistent proteinuria and entered end stage renal disease (ESRD) at 11 years old. The other one had an onset age of 6 months with no response to steroids initially. She got complete remission by tacrolimus administered, but relapse frequently and partially responded to steroids later. Two patients of this group died, one of them died of respiratory failure 3 days after birth. Excessive amniotic fluid and fetal edema were acknowledged at 28 weeks of gestational age. He harbored compound heterozygous variants of NPHS1, c.1135C>G (R379G) and c.1339G>A (E447K). His mother previously experienced fetal death at 28 weeks gestational age for her first pregnant and stillborn at 36 weeks of gestational age for her second pregnant, respectively. One patient in this study who harbored homozygous variant of c.1339G>A (E447K) presented with a mild phenotype, onset age was 13 years old and didn't progress to ESRD yet at 21 years. Thus, variant E447K was hypothesized to be weakly pathogenic, while R379G may be strongly pathogenic with a risk of death. Five novel variants were identified in this group of patients, 3 missense variants (c.1135C>G, c.1157A>T, c.3197T>A) and 2 frameshift variants (c.709_710delCT, c.3193delG). Renal biopsy was performed in 4 cases, of whom two were focal segmental glomerular sclerosis and another two were minimal change disease. Conclusions:NPHS1-VAN possesses remarkable clinical and genetic heterogeneity. Five novel variants were identified. Missense variant is the most common variant type and c.928G>A is the most common one in this group of patients, in consistent with previous report in China. Children harbor c.928G>A may have a mild phenotype with possible spontaneous remission and may be response to steroids and calcineurin inhibitor. Variant c.1135C>G (R379G) may have a strong pathogenicity, and patient who harbors this variant may have a severe phenotype.

Joubert syndrome is a rare primary ciliopathy characterized by hypoplasia of the midbrain and vermis cerebellum, with or without extracerebral organs involvement. This article reports a case of Joubert syndrome with RPGRIP1L mutation, presented with anemia, renal dysfunction, growth retardation, and mental retardation. The patient reached end-stage renal disease at the age of 13 years old. Magnetic resonance imaging of the brain revealed slight elongation of the superior cerebellar peduncles, mild hypoplasia of the cerebellar vermis, and the characteristic "molar tooth sign". Elevated transaminase and γ-glutamyl transpeptidase levels were detected at the age of 14 years old. Genetic analysis showed a compound heterozygous mutation in the RPGRIP1L gene (c.1290_1291delGT, c.3764T>C). Joubert syndrome is a clinically heterogeneous disorder and easy to be missed. Early diagnosis and standard treatment contribute to a better prognosis.

OBJECTIVE To develop a population pharmacokinetic （PPK） model for mycophenolate mofetil active metabolite mycophenolic acid （MPA） in children with primary IgA nephropathy， explore the factors affecting the pharmacokinetic parameters of MPA， and provide a basis for clinical individualized therapy. METHODS Retrospective collection was conducted on 636 concentrations and clinical data from 47 pediatric patients with primary IgA nephropathy. PPK analysis was carried out by using the nonlinear mixed-effects model； the covariates were tested with a stepwise method. Goodness-of-fit plots， Bootstrap and visual predictive check were employed to evaluate the final model. RESULTS The pharmacokinetics of MPA in children with IgA nephropathy in vivo conformed to the first-order absorption and elimination two-compartment model （objective function value of 3 276.31）. Covariate analysis suggested that body weight and albumin （ALB） levels were significant influencing factors on apparent clearance rate and apparent distribution volume. The typical values of PPK parameters of MPA in the final model were as follows： the central room had a distributed volume of 5.79 L， the clearance rate was 4.06 L/h， the volume of peripheral ventricular distribution was 430.93 L， the clearance rate between compartments was 15.40 L/h， the oral absorption rate constant was 1.29 h－1. After verification， most of the predicted corrected observed concentration points were within the 90% confidence interval of the predicted corrected simulated concentration， indicating that the MPA final model had good predictive performance. CONCLUSIONS The PPK model of MPA in children with primary IgA nephropathy is established in this study， identifying body weight and ALB levels are significant factors affecting MPA metabolism.

Objective To explore the activation of tumor necrosis factor-α(TNF-α)signaling pathway and the expressions of the associated inflammatory factors in NPHP1-defective renal tubular epithelial cells.Methods A human proximal renal tubular cell(HK2)model of lentivirus-mediated NPHP1 knockdown(NPHP1KD)was constructed,and the expressions of TNF-α,p38,and C/EBPβ and the inflammatory factors CXCL5,CCL20,IL-1β,IL-6 and MCP-1 were detected using RT-qPCR,Western blotting or enzyme-linked immunosorbent assay.A small interfering RNA(siRNA)was transfected in wild-type and NPHP1KDHK2 cells,and the changes in the expressions of TNF-α,p38,and C/EBPβ and the inflammatory factors were examined.Results NPHP1KDHK2 cells showed significantly increased mRNA expressions of TNF-α,C/EBPβ,CXCL5,IL-1β,and IL-6(P<0.05),protein expressions of phospho-p38 and C/EBPβ(P<0.05),and IL-6 level in the culture supernatant(P<0.05),and these changes were significantly blocked by transfection of cells with siRNA-C/EBPβ(P<0.05).Conclusion TNF-α signaling pathway is activated and its associated inflammatory factors are upregulated in NPHP1KDHK2 cells,and C/EBPβ may serve as a key transcription factor to mediate these changes.

Objective To explore the activation of tumor necrosis factor-α(TNF-α)signaling pathway and the expressions of the associated inflammatory factors in NPHP1-defective renal tubular epithelial cells.Methods A human proximal renal tubular cell(HK2)model of lentivirus-mediated NPHP1 knockdown(NPHP1KD)was constructed,and the expressions of TNF-α,p38,and C/EBPβ and the inflammatory factors CXCL5,CCL20,IL-1β,IL-6 and MCP-1 were detected using RT-qPCR,Western blotting or enzyme-linked immunosorbent assay.A small interfering RNA(siRNA)was transfected in wild-type and NPHP1KDHK2 cells,and the changes in the expressions of TNF-α,p38,and C/EBPβ and the inflammatory factors were examined.Results NPHP1KDHK2 cells showed significantly increased mRNA expressions of TNF-α,C/EBPβ,CXCL5,IL-1β,and IL-6(P<0.05),protein expressions of phospho-p38 and C/EBPβ(P<0.05),and IL-6 level in the culture supernatant(P<0.05),and these changes were significantly blocked by transfection of cells with siRNA-C/EBPβ(P<0.05).Conclusion TNF-α signaling pathway is activated and its associated inflammatory factors are upregulated in NPHP1KDHK2 cells,and C/EBPβ may serve as a key transcription factor to mediate these changes.

OBJECTIVE: To explore the genetic basis for a child presented with renal failure and multi-cystic dysplastic kidney without anal atresia. METHODS: Peripheral blood sample of the child and his parents were collected and subjected to whole exome sequencing. Candidate variant was verified by Sanger sequencing. RESULTS: The 40-day-old infant had presented with vomiting brown matter in a 7 days neonate and was transferred for kidney failure. Clinical examination has discovered renal failure, polycystic renal dysplasia, congenital hypothyroidism, bilateral thumb polydactyly, sensorineural hearing loss and preauricular dermatophyte. Genetic testing revealed that he has harbored a previously unreported c.824delT, p.L275Yfs*10 frameshift variant of SALL1 gene, which was confirmed by Sanger sequencing as de novo. CONCLUSION The patient was diagnosed with Townes-Brocks syndrome due to the novel de novo variant of SALL1 gene. Townes-Brocks syndrome without anal atresia is rare. Above finding has also enriched the mutational spectrum of the SALL1 gene.
Abnormalities, Multiple ; Anus, Imperforate/genetics* ; Child ; Female ; Hearing Loss, Sensorineural/genetics* ; Humans ; Infant ; Infant, Newborn ; Male ; Renal Insufficiency ; Thumb/abnormalities* ; Transcription Factors/genetics*

Objective:To explore the characteristics of Lowe syndrome, as well as OCRL1 gene mutation and its relationship with phenotype. Methods:Children diagnosed with Lowe syndrome during their visit to Nanfang Hospital of Southern Medical University (4 cases) and the First Affiliated Hospital of Sun Yat-sen University (3 cases) from January 2009 to January 2019 were included. The clinical data and peripheral blood samples were collected, and the sequence analysis of OCRL1 was performed after genomic DNA extraction. Then the clinical features of the children and the relationship between OCRL1 mutation and clinical phenotype were analyzed. Results:Seven patients from 6 families who presented with Lowe syndrome were included. All of them had different degrees of ocular-neural-renal symptoms. Six cases from 5 families had congenital cataract and neonatal hypotonia, one case from another family only had a thin lens without cataract. Four cases had nystagmus and 2 cases had glaucoma. Six cases from 6 families had psychomotor retardation and had proximal tubular impairment, included low-molecular-weight proteinuria (LMWP). Serum aspartate transaminase (AST), lactate dehydrogenase (LDH), creatine kinase (CK) and creatine kinase-MB (CK-MB) were increased in all 6 patients who were tested. Mutations of OCRL1 were detected in all the 6 families, which located in exon 10, 13, 16, 18, 22 and 23 respectively. The mutations of c.891 G>T, c.1682_1683insAA and c.2564_2567del are novel. Conclusions:Three OCRL1 novel mutations in 6 Chinese Lowe syndrome families are identified. The clinical manifestations in different mutations of OCRL1 are heterogeneous. The mutations of c.891 G>T in exon 10 without congenital cataract is rare in clinical.

Objective: To explore the clinical and pathological features and mutational types and their relations with WT1 mutation-associated nephropathy (WT1MAN). Methods: The clinical and pathological data and the results of WT1 mutation analysis of the cases from Nanfang Hospital of Southern Medical University, Sun Yat-sen Memorial Hospital and The First Affiliated Hospital of Sun Yat-sen University whom we recruited recently and reported during the last ten years were analyzed. Results: Totally, 20 cases (6 males and 14 females), included 5 newly diagnosed cases, were recruited. (1) Ten children were diagnosed with Denys-Drash syndrome (DDS): The median onset age of proteinuria was 1 year and 7 months. Diffuse mesangial sclerosis (DMS) were revealed in 3 cases, minimal lesions (MCD) in 4 cases, and focal segmental glomerulosclerosis (FSGS) in 1 case; renal pathology was not available in the other 2 cases. Glomerular basement membrane (GBM) thickening was observed in 2 cases. Calcineurin inhibitors (CNIs) were administered in 5 cases, complete remission of proteinuria was observed in 3 cases, partial remission in the other 2 cases. Genetic analysis revealed that six cases had WT1 missense mutation, 3 had nonsense mutation, and 1 had frameshift mutation. (2) Two cases were diagnosed with Frasier syndrome (FS): proteinuria was observed at 1 year and 1 month of age and 1 year and 9 months of age, respectively. FSGS with GBM layering were observed in both cases. They progressed to ESRD at 1 year and 6 months of age and 6 years and 6 months of age, respectively. CNI was tried in 1 case with partial proteinuria remission. Both patients were detected to have WT1 splice mutation. (3) Isolated nephropathy (IN) was observed in 8 cases: three had splice mutation, 5 had missense mutation. Of the 3 patients with splice mutation, one was found to have nephropathy and renal failure at the age of 5 months. The other two cases (1 was FSGS and another MCD), both had GBM layering. CNIs were tried on both of them, one got partial remission with normal renal function at the age of fourteen years, the other one had no response and entered ESRD at the age of 6 years and 9 months. Of the 5 cases with missense mutation, 3 had DMS, 2 of them entered ESRD within 6 months of age, another case had DMS entered ESRD at 9 years of age. One case with FSGS, was treated with CNIs and got complete remission. Conclusions Slow progression (7/10) nephropathy was observed in DDS patients. Missense mutation (11/20) was the most common type of WT1 variants, followed by splice mutation (5/20) in this group of patients. Early onset nephropathy (4/5), rapid progression (4/5) and GBM layering (4/4) wereobserved in patients with splice mutation. CNI was effective in reducing or even eliminating proteinuria in WT1 MAN patients (8/9).