With the continuous refinement of China's rare disease prevention and treatment policies, the diagnosis and treatment capacity for rare diseases in China has been steadily improved; however, delayed diagnosis, inadequate transition of care, and poor continuity of long-term management remain common, particularly in pediatric rare diseases. Pediatric rare diseases often arise during critical developmental stages and exhibit age-dependent phenotypic evolution, such that diagnostic delays may lead to the missing of critical intervention windows. As the leading institution of the Hubei Provincial Rare Disease Medical Center and the Rare Disease Quality Control Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology (hereinafter referred to as "Tongji Hospital") has established and implemented a rare disease discipline cluster model centered on platform convergence and specialty clustering. This model centers on the whole-life-cycle management needs of pediatric rare diseases, and constructs a systematic operational framework covering technical and data support, platform governance, specialized cluster operation, as well as regional and policy coordination. By summarizing the organizational pathway and practical effects of the rare disease discipline cluster construction at Tongji Hospital, this paper aims to provide a reference for general hospitals in promoting the development of rare disease diagnosis and treatment systems.

Objective Through molecular genetics analysis of a calculi family lineage,this study aims to explore its pathogenesis and the association between genotypes and phenotypes.Methods A retrospective analysis was conducted on a calculi family lineage admitted to Tongji Hospital,affiliated with Tongji Medical College,Huazhong University of Science and Technology.Clinical data and peripheral blood samples of the affected children and some family members were collected.Whole exome sequencing was performed,followed by Sanger sequencing to validate the candidate variants.Results Among the 38 family members across four generations,10 members were diagnosed with calculi disease.The second generation,member 2(Ⅱ-2),third generation,member 2(Ⅲ-2),and third generation,member 4(Ⅲ-4)suffered from recurrent multiple kidney stones and gallstones.The second generation,member 6(Ⅱ-6),second generation,member 13(Ⅱ-13),and third generation,member 5(Ⅲ-5)had recurrent multiple kidney stones alone,while first generation,member 2(Ⅰ-2),second generation,member 4(Ⅱ-4),second generation,member 8(Ⅱ-8),and second generation,member 11(Ⅱ-11)only had gallstones.No other family members exhibited any signs of kidney or gallbladder involvement.Ⅱ-2 was diagnosed in 2018 with end-stage renal disease stage 5,grade 3 hypertension and gallstones,urinary amino acid high-performance liquid chromatography analysis indicated elevated urinary cystine.This member had a history of recurrent multiple kidney stones and recurrent urinary tract infections for over 30 years,with multiple histories of ureteroscopic stone removal.Genetic analysis revealed that Ⅱ-2,Ⅲ-2,Ⅲ-4,Ⅲ-5 and Ⅳ-1 all carry a heterozygous mutation in exon 10 of the solute carrier family 3 member 1(SLC3A1)gene,c.1889G＞A(p.Gly630Asp).The third generation,member 1(Ⅲ-1),and fourth generation,member 2(Ⅳ-2),are wild type.This mutation shows a phenomenon of family co-segregation.Conclusions The heterozygous mutation of SLC3A1 gene,c.1889G＞A,may be the genetic cause of calculi disease in multiple members of this family lineage.Recurrent multiple kidney stones and/or gallstones require high attention to genetic etiology.It is recommended to perform genetic analysis on calculi family lineages and patients with early-onset calculi disease.

Objective To establish a pediatric rare disease catalog,analyze the current status of therapeutic drugs and their coverage of the medical insurance in China,and propose strategies to enhance drug accessibility.Methods Pediatric rare diseases were identified from China's two national rare disease catalogs combined with the EU Orphanet database,US FDA orphan drug database,and the Diagnosis and Treatment Standards for Rare Diseases in Children.We created a specialized drug catalog for pediatric rare diseases,then analyzed drug types(ATC classification),pricing,and medical insurance coverage using descriptive statistics based on Yaozhi.com drug bidding prices and the 2024 Drug of List National Basic Medical Insurance(NBMIDL).Drug affordability was assessed through annual treatment cost calculations.Results The national catalogs included 151 pediatric rare diseases(72.95%of listed conditions),spanning 13 disease systems.We identified 94 dedicated orphan drugs(by generic name)for these conditions,among which 43 were approved internationally but unavailable in China.The average unit price per package was 6 113.53 yuan.Overall NBMIDL coverage was 68.83%,but drugs priced above 7 000 yuan per unit had only 7.69%coverage.Annual treatment costs reached 4.54 million for laronidase(mucopolysaccharidosis).Conclusions Critical gaps persist in China's pediatric rare disease treatment landscape,including catalog deficiencies,inadequate coverage for high-cost drugs and insufficient domestic innovation.It is recommended to establish a list of orphan drugs for pediatric rare diseases,accelerate the import of foreign drugs and the local innovative drugs through policy incentives,optimizing medical insurance reimbursement mechanisms for pediatric rare disease drugs to comprehensively improve therapeutic accessibility.

To investigate the clinical characteristics,genetic mutation patterns,and therapeutic strategies of an infant with interstitial lung disease associated with a surfactant protein C(SFTPC)gene mutation,and systematic review of 188 cases of SFTPC mutation-elated childhood ILD(chILD)reported in Chinese and English literature(from database inception to December 2024)was conducted.The patient in this study was a girl aged 11 months.She presented with progressive dyspnea,hypoxemia,and severe growth retardation starting at 2 months of age.Whole-exome sequencing identified a heterozygous missense mutation in SFTPC(c.187A>G,p.K63E),inherited from her mother.Symptoms significantly improved after treatment with glucocorticoids and azithromycin,though pulmonary bullae persisted at 5-year follow-up.Literature analysis revealed that the hotspot mutation I73T was located in the linker domain,while BRICHOS domain mutations exhibited the highest genetic diversity.BRICHOS domain mutations were associated with earlier onset,whereas non-BRICHOS mutations predominantly manifested in infancy with chronic cough,hypoxemia,and growth retardation.Oxygen therapy and glucocorticoids were the most common treatments.Hydroxychloroquine was more frequently used in linker domain mutations.The overall survival rate was 84%.SFTPC mutations are a critical genetic etiology of chILD in infants.Early genetic testing combined with glucocorticoid/macrolide therapy improves prognosis,but long-term monitoring for structural lung damage(e.g.,pulmonary bullae)is essential.

Objective To establish a pediatric rare disease catalog,analyze the current status of therapeutic drugs and their coverage of the medical insurance in China,and propose strategies to enhance drug accessibility.Methods Pediatric rare diseases were identified from China's two national rare disease catalogs combined with the EU Orphanet database,US FDA orphan drug database,and the Diagnosis and Treatment Standards for Rare Diseases in Children.We created a specialized drug catalog for pediatric rare diseases,then analyzed drug types(ATC classification),pricing,and medical insurance coverage using descriptive statistics based on Yaozhi.com drug bidding prices and the 2024 Drug of List National Basic Medical Insurance(NBMIDL).Drug affordability was assessed through annual treatment cost calculations.Results The national catalogs included 151 pediatric rare diseases(72.95%of listed conditions),spanning 13 disease systems.We identified 94 dedicated orphan drugs(by generic name)for these conditions,among which 43 were approved internationally but unavailable in China.The average unit price per package was 6 113.53 yuan.Overall NBMIDL coverage was 68.83%,but drugs priced above 7 000 yuan per unit had only 7.69%coverage.Annual treatment costs reached 4.54 million for laronidase(mucopolysaccharidosis).Conclusions Critical gaps persist in China's pediatric rare disease treatment landscape,including catalog deficiencies,inadequate coverage for high-cost drugs and insufficient domestic innovation.It is recommended to establish a list of orphan drugs for pediatric rare diseases,accelerate the import of foreign drugs and the local innovative drugs through policy incentives,optimizing medical insurance reimbursement mechanisms for pediatric rare disease drugs to comprehensively improve therapeutic accessibility.

To investigate the clinical characteristics,genetic mutation patterns,and therapeutic strategies of an infant with interstitial lung disease associated with a surfactant protein C(SFTPC)gene mutation,and systematic review of 188 cases of SFTPC mutation-elated childhood ILD(chILD)reported in Chinese and English literature(from database inception to December 2024)was conducted.The patient in this study was a girl aged 11 months.She presented with progressive dyspnea,hypoxemia,and severe growth retardation starting at 2 months of age.Whole-exome sequencing identified a heterozygous missense mutation in SFTPC(c.187A>G,p.K63E),inherited from her mother.Symptoms significantly improved after treatment with glucocorticoids and azithromycin,though pulmonary bullae persisted at 5-year follow-up.Literature analysis revealed that the hotspot mutation I73T was located in the linker domain,while BRICHOS domain mutations exhibited the highest genetic diversity.BRICHOS domain mutations were associated with earlier onset,whereas non-BRICHOS mutations predominantly manifested in infancy with chronic cough,hypoxemia,and growth retardation.Oxygen therapy and glucocorticoids were the most common treatments.Hydroxychloroquine was more frequently used in linker domain mutations.The overall survival rate was 84%.SFTPC mutations are a critical genetic etiology of chILD in infants.Early genetic testing combined with glucocorticoid/macrolide therapy improves prognosis,but long-term monitoring for structural lung damage(e.g.,pulmonary bullae)is essential.

Objective Through molecular genetics analysis of a calculi family lineage,this study aims to explore its pathogenesis and the association between genotypes and phenotypes.Methods A retrospective analysis was conducted on a calculi family lineage admitted to Tongji Hospital,affiliated with Tongji Medical College,Huazhong University of Science and Technology.Clinical data and peripheral blood samples of the affected children and some family members were collected.Whole exome sequencing was performed,followed by Sanger sequencing to validate the candidate variants.Results Among the 38 family members across four generations,10 members were diagnosed with calculi disease.The second generation,member 2(Ⅱ-2),third generation,member 2(Ⅲ-2),and third generation,member 4(Ⅲ-4)suffered from recurrent multiple kidney stones and gallstones.The second generation,member 6(Ⅱ-6),second generation,member 13(Ⅱ-13),and third generation,member 5(Ⅲ-5)had recurrent multiple kidney stones alone,while first generation,member 2(Ⅰ-2),second generation,member 4(Ⅱ-4),second generation,member 8(Ⅱ-8),and second generation,member 11(Ⅱ-11)only had gallstones.No other family members exhibited any signs of kidney or gallbladder involvement.Ⅱ-2 was diagnosed in 2018 with end-stage renal disease stage 5,grade 3 hypertension and gallstones,urinary amino acid high-performance liquid chromatography analysis indicated elevated urinary cystine.This member had a history of recurrent multiple kidney stones and recurrent urinary tract infections for over 30 years,with multiple histories of ureteroscopic stone removal.Genetic analysis revealed that Ⅱ-2,Ⅲ-2,Ⅲ-4,Ⅲ-5 and Ⅳ-1 all carry a heterozygous mutation in exon 10 of the solute carrier family 3 member 1(SLC3A1)gene,c.1889G＞A(p.Gly630Asp).The third generation,member 1(Ⅲ-1),and fourth generation,member 2(Ⅳ-2),are wild type.This mutation shows a phenomenon of family co-segregation.Conclusions The heterozygous mutation of SLC3A1 gene,c.1889G＞A,may be the genetic cause of calculi disease in multiple members of this family lineage.Recurrent multiple kidney stones and/or gallstones require high attention to genetic etiology.It is recommended to perform genetic analysis on calculi family lineages and patients with early-onset calculi disease.

Objective:To analyze and summarize the clinical, genotypic and pathological characteristics of children with PAX2 gene mutation in China, and to provide information for the monitoring, treatment and prognosis of the disease. Methods:It was a case series analysis study. The clinical data of children with PAX2 gene mutation in Pediatric Nephrology Department, Tongji Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology from January 2014 to December 2022 were collected, and peripheral blood gene DNA was extracted and sequenced for whole exome sequencing. The clinical, pathological and genotypic characteristics of PAX2 gene variation of children in China were summarized by searching PubMed, Medline, China National Knowledge Infrastructure and Wanfang database and compared with the cases in this single center. Results:Among the 13 children with PAX2 gene mutation, there were 9 males and 4 females, 12 patients with abnormal urine tests, 7 patients with small kidney volume by imaging examination, and 5 patients with renal cysts. The clinical phenotypes were congenital renal and urinary tract malformations in 8 cases, renal coloboma syndrome in 1 case, and hematuria or proteinuria in 3 cases. Five patients underwent renal biopsies, showing focal segmental glomerulosclerosis and C3 glomerulopathy in 1 case, focal segmental glomerulosclerosis in 1 case, thin basement membrane lesion in 1 case, and IgA nephropathy in 2 cases. The genetic testing in 13 children showed 9 de novo mutations and 4 new mutations of c.321G>A, c.213-8C>G, c.63C>A and c.449C>T. There were 2 cases of 76dupG (p.V26Gfs*28) mutant. A total of 51 Chinese children with PAX2 gene mutation were found in the literature search. There were 32 males and 19 females, 8 cases with small kidney volume and 12 cases with renal cysts. The clinical phenotypes were congenital anomalies of kidney and urinary tract in 28 cases, renal coloboma syndrome in 17 cases, and hematuria or proteinuria in 6 cases. Seven patients underwent renal biopsies, including 2 cases with focal segmental glomerulosclerosis, 1 case with minimal lesion, 1 case with mesangial proliferative glomerulonephritis, 1 case with IgA nephropathy, 1 case with membranous nephropathy and a case with focal proliferative sclerosing purpura nephritis combined with glomerular hypertrophy. Thirty-four cases were de novo mutations, and 12 mutations were from the father or mother. The father or mother of 5 children had no clinical manifestations, with normal renal function. There were 11 cases of 76dupG (p.V26Gfs*28) mutant. Conclusions:The clinical phenotypes and genotypes of PAX2 gene variation in Chinese children are diverse. The most common clinical phenotype of PAX2 gene variation is congenital anomalies of kidney and urinary tract. c.76dupG (p.V26Gfs*28) is the most common of PAX2 gene variant.

To improve the understanding of clinicians on the diagnostic criteria and treatment principlis of pulmonary alveolar proteinosis(PAP),which is a rare respiratory disease.European Respiratory Society published the first edition guidelines for PAP,including a systematic review of the literature and the application of the grading of recommendations,assessment,development and evaluation(GRADE)approach to assess the certainty of evidence and the strength of recommendations.Five questions of patient,intervention,comparison,outcome(PICO)and two narrative questions were developed.Recommendations and evidence-based evidence were given,including management of PAP,whole lung lavage,granulocyte-macrophage colony-stimulating factor(GM-CSF)therapy,rituximab,plasma exchange,and lung transplantation.In addition,recommendations were given for the use of GM-CSF antibody testing,bronchoalveolar lavage,and lung biopsy.This study is to interpret the main content of the guideline.

Alport syndrome is a type of hereditary kidney disease caused by mutations in the type Ⅳ collagen gene.Depending on the genetic mode,it can be divided into X-linked Alport syndrome,autosomal dominant Alport syndrome,autosomal recessive Alport syndrome,and digenic Alport syndrome.The clinical manifestations are heterogeneous,ranging from isolated hematuria or hematuria with proteinuria to progressive renal failure,with or without extrarenal manifestations.This article reviews the genetic characteristics,biomarkers,and treatment-related research of Alport syndrome,aiming to provide reference for enhancing early diagnosis and treatment and optimize long-term prognosis.