Objective:To analyze the clinical features and CBS gene variants of 13 patients with classic homocystinuria, and the strategies of individual treatment and prevention were explored.Methods:The general information, clinical manifestations, laboratory tests, cranial images, CBS gene variants, diagnosis and therapeutic strategies of 13 patients with classic homocystinuria admitted to the Department of Pediatrics of Children′s Hospital Affiliated to Zhengzhou University and Peking University First Hospital from November 2013 to June 2021 were analyzed retrospectively.Results:There were 13 patients diagnosed at the age of 10 days to 14 years, 6 were male and 7 were female. There were 3 patients detected by newborn screening and received treatment at the asymptomatic stage. There were 10 patients clinically diagnosed at the age of 5 to 14 years. Their symptoms appeared at age of 1 to 6 years. The major clinical manifestations were marfanoid features, lens dislocation and (or) myopia, developmental delay, osteoporosis, and cardiovascular diseases. Brain magnetic resonance imaging showed asymmetric infarcts in 4 patients and hypomyelination in 1 case. Increased blood methionine, plasma total homocysteine and urinary total homocysteine with normal urinary methylmalonic acid were found in 13 patients. The biochemical features were consistent with classic homocystinuria. Totally 18 variants were identified in CBS gene of 13 patients, 10 variants were novel and 8 were reported. only 1 patient was partially responsive to vitamin B 6 treatment, while 12 cases were non-responsive. They were mainly treated with low methionine diet and betaine supplement. Three vitamin B 6 non-responsive cases received liver transplantation at age of 3, 8 and 8 years, respectively. Their blood methionine and total homocysteine returned to normal within a week after liver transplantation. One patient died. Prenatal diagnosis was performed for a fetus when the mother was pregnant again. Two pathogenic CBS gene variants were identified from the amniocytes as same as the proband. Conclusions:The clinical manifestations of classic homocystinuria are complex and variable. Blood amino acid analysis, serum or urine total homocysteine assay and gene analysis are critical for its diagnosis. There were 10 novel CBS gene varients were identified expanding the CBS gene varient spectrum. Liver transplantation is an effective treatment. Prenatal diagnosis is important to prevent classic homocysteinuria.

Objective:To investigate the factors affecting phenotypes in the patients of methylmalonic acidemia combined with homocysteinemia cblC type with MMACHC c. 609G>A homologous variant. Methods:A retrospective study on the clinical manifestations, complications, treatment, and outcome in 164patients of cblC type with MMACHC c. 609G>A homologous variant was conducted.The patients were diagnosed by biochemical and genetic analysisfrom January 1998 to December 2020. Results:Among the 164 patients, 2 cases were prenatally diagnosed and began treatment after birth. They are 3 and 12 years old with normal physical and mental development. Twenty-one cases were diagnosed by newborn screening. Among them, 15 cases had with normal development. They were treated fromthe age of two weeks at the asymptomatic period. Six cases began treatment aged 1 to 3 months after onset. Their development was delayed. One hundred and forty-one cases were clinically diagnosed. Their onset age ranges from a few minutes after birth to 6 years old. 110 cases had early-onset (78.0%). 31 cases had late-onset (22.0%). Five of them died. 24 patients lost to follow-up. Of the 141 clinically diagnosed patients, 130 (92.2%) with psychomotor retardation, 69 (48.9%) with epilepsy, 39 (27.7%) with anemia, 30 (21.3%) had visual impairment, 27 (19.1%) had hydrocephalus, 26 (18.4%) had feeding difficulties, 7 (5.0%) with liver damage, and 5 (3.5%) with metabolic syndrome. The frequency of hydrocephalus and seizures was significantly higher in the early-onset group. The urinary methylmalonic acid increased significantly in the patients with epilepsy. During the long-term follow-up, the level of plasma total homocysteine in the seizure-uncontrolled group was significantly higher than that in the seizure-controlled group, the difference had a statistical significance ( P<0.05). Conclusion:Most of the patients with MMACHC c. 609G>A homozygous variant had early-onset disease, with a high mortality and disability rate. If not treated in time, it will lead to neurological damage, resulting in epilepsy, mental retardation, hydrocephalus, and multiple organ damage. Pre-symptomatic diagnosis and treatment are crucial to prevent irreversible neurological damage. Neonatal screening and prenatal diagnosis are important to improve the outcome of the patients.

Objective:To analyze the clinical features, genetic characteristics, treatment and follow-up results of patients with hydrocephalus caused by methylmalonic acidemia combined with homocysteinuria, and to discuss the optimal strategies for assessing and treating such patients.Methods:From January 1998 to December 2020, 76 patients with hydrocephalus due to methylmalonic acidemia combined with homocysteinuria in the Department of Pediatrics in 11 hospitals including Peking University First Hospital were diagnosed by biochemical, genetic analysis and brain imaging examination. The patients were divided into operation-group and non-operation-group according to whether they underwent ventriculoperitoneal shunt. The clinical features, laboratory examinations, genotype, and follow-up data were retrospectively analyzed. Data were compared between the two groups using rank sum test, and categorical data were compared using χ 2 test. Results:Among the 76 patients (51 male, 25 female), 5 were detected by newborn screening, while 71 were diagnosed after clinical onset, 68 cases (96%) had early-onset, 3 cases (4%) had late-onset. The most common clinical manifestations of 74 cases with complete data were psychomotor retardation in 74 cases (100%), visual impairment in 74 cases (100%), epilepsy in 44 cases (59%), anemia in 31 cases (42%), hypotonia or hypertonia in 21 cases (28%), feeding difficulties in 19 cases (26%) and disturbance of consciousness in 17 cases (23%). Genetic analysis was performed in 76 cases, all of whom had MMACHC gene variations, including 30 homozygous variations of MMACHC c.609G>A. The most common variations were c.609G>A (94, 62.7%), followed by c.658_660del (18, 12.0%), c.567dupT (9, 6.0%) and c.217C>T (8, 5.3%). Therapy including cobalamin intramuscular injection, L-carnitine and betaine were initiated immediately after diagnosis. A ventriculoperitoneal shunt operation was performed in 41 cases (operation group), and 31 patients improved after metabolic intervention (non-operation group). There was no significant difference in the age of onset, the age of diagnosis, the blood total homocysteine, methionine, and urinary methylmalonic acid concentration between the two groups (all P>0.05). The symptoms of psychomotor development, epilepsy, and visual impairments improved gradually after a long-term follow-up in the operation group. Conclusions:Hydrocephalus is a severe complication of methylmalonic acidemia combined with homocysteinuria. The most common clinical manifestations are psychomotor retardation, visual impairment, and epilepsy. It usually occurs in early-onset patients. Early diagnosis and etiological treatment are very important. Hydrocephalus may improve after metabolic intervention in some patients. For patients with severe ventricular dilatation, prompt surgical intervention can improve the prognosis.

Objectives:To summarize the clinical and genetic characteristics of the patients with isolated methylmalonic acidemia and investigate the strategies for the diagnosis, treatment and prevention.Methods:Three hundred and fourteen patients (180 males, 134 females) with isolated methylmalonic acidemia were ascertained from 26 provinces or cities across the mainland of China during January 1998 to March 2020. Genetic analysis was performed by Sanger sequencing, gene panel sequencing, whole exome sequencing, multiplex ligation-dependent probe amplification or quantitative PCR. According to the age of onset, the patients were divided to early-onset group (≤12 months of age) and the late-onset group (>12 months of age). They were treated by cobalamin, L-carnitine and (or) special diet and symptomatic treatment. Statistical analysis was done using Chi-square test.Results:Fifty-eight of 314 (18.5%) patients were detected by Newborn screening using liquid chromatography tandem mass spectrometry. Five cases (1.6%) had a postmortem diagnosis. Two hundred and fifty-one patients (79.9%) were clinically diagnosed with an age of onset ranged from 3 hours after birth to 18 years. One hundred and fifty-nine patients (71.0%) belonged to early-onset groups, 65 patients (29.0%) belonged to the late-onset group. The most common symptoms were metabolic crises, psychomotor retardation, epilepsy, anemia and multiple organ damage. Metabolic acidosis and anemia were more common in early-onset patients than that in late-onset patients (20.8%(33/159) vs. 9.2% (6/65), 34.6% (55/159) vs. 16.9% (11/165), χ 2=4.261, 6.930, P=0.039, 0.008). Genetic tests were performed for 236 patients (75.2%), 96.2%(227/236) had molecular confirmation. One hundred and twenty-seven variants were identified in seven genes (MMUT, MMAA, MMAB, MMADHC, SUCLG1, SUCLA2, and MCEE), of which 49 were novel. The mut type, caused by the deficiency of methylmalonyl-CoA mutase, was the most common ( n=211, 93%) cause of this condition. c.729_730insTT, c.1106G>A and c.914T>C were the three most frequent mutations in MMUT gene. The frequency of c.914T>C in early-onset patients was significantly higher than that in late-onset patients (8.3% (18/216) vs. 1.6% (1/64), χ 2=3.859, P=0.037). Metabolic crisis was more frequent in mut type than the other types (72.6% (114/157) vs. 3/13, χ 2=13.729, P=0.001),developmental delay and hypotonia were less frequent in mut type (38.2% (60/157) vs. 9/13, 25.5% (40/157) vs. 8/13, χ 2=4.789, 7.705, P=0.030, 0.006). Of the 58 patients identified by newborn screening, 44 patients (75.9%) who were treated from asymptomatic phase developed normally whereas 14 patients (24.1%) who received treatment after developing symptoms exhibited varying degrees of psychomotor retardation. Conclusions:The characteristics of phenotypes and genotypes among Chinese patients with isolated methylmalonic acidemia were analyzed. Expanded the mutation spectrum of the associated genes. Because of the complex clinical manifestations and severe early onset of isolated methylmalonic acidemia, Newborn screening is crucial for early diagnosis and improvement of prognosis. MMUT gene is recommended for carrier screening as an effort to move the test earlier as a part of the primary prevention of birth defects.

Objective To investigate the clinical,biochemical and genetic features of hereditary hypomagnesaemia with secondary hypocalcaemia.Methods Two boys came from different Chinese families.They were hospitalized at the Peking University First Hospital between 2014 and 2016 at the age of 9 years and 1 year and 2 months because of epilepsy and psychomotor retardation.Clinical investigation,laboratory examination,and medical imaging were performed for the etiological study.Whole-genome sequencing was used for the genetic analysis of the patients.Mutations of TRPM6 gene were confirmed by means of Sanger sequencing.Results Patient 1 presented with recurrent seizures and psychomotor retardation from the age of 3 months.Vision loss and psychomotor regression were noticed from the age of 9 years,accompanied with hypertension.Serum magnesium and total calcium were significandy decreased to 0.13-0.15 mmol/L and 1.43-2.00 mmol/L,respectively in patient 1.Serum potassium was reduced to 1.85-3.25 mmol/L.Blood parathyroid hormone was also decreased.On the TRPM6 gene of patient 1,2 novel non-sense mutations,c.2771G ＞ A (p.Trp924Ter) and c.115C ＞ T (p.Gln39Ter) were identified.Patient 2 presented with seizures and psychomotor retardation at the age of 2 weeks.Both of his serum magnesium (0.17-0.35 mmol/L) and serum total calcium (1.32-1.34 mmol/L) were significantly decreased.Blood parathyroid hormone was decreased.Two novel mutations (c.1239G ＞ A,p.W413X and c.146G ＞ A,p.C49Y) were found in the TRPM6 gene of patient 2.Severe hypomagnesaemia,hypocalcaemia and TRPM6 gene mutations confirmed the diagnosis of hereditary hypomagnesaemia with secondary hypocalcaemia in the 2 patients.After the large-dose supplement of magnesium sulfate,progressive clinical improvements were observed in the 2 patients.However,because of the severe brain damage,patient 1 still had psychomotor retardation.Patient 2 completely recovered.Conclusions Hereditary hypomagnesaemia with secondary hypocalcaemia is a severe inherited metabolic disease.Early diagnosis and large-dose magnesium supplement are the key to the good prognosis of the patients.In this study,2 Chinese children with the clinical onset of epilepsy and psychomotor retardation are reported.The diagnosis is made by way of blood biochemical assay and gene analysis.Four novel mutations on their TRPM6 gene are identified.

Objective: To analyz the current situation of the diagnosis, treatment and prevention of methylmalonic acidemia, the phenotypes, biochemical features and genotypes of the patients in the mainland of China, were investigated. Methods: Tottally 1 003 patients of methylmalonic acidemia from 26 provinces and municipalities of the mainland of China were enrolled. The clinical data, biochemical features and gene mutations were studied. Blood aminoacids and acylcarnitines, urine organic acids, and plasma total homocysteine were determined for the biochemical diagnosis. Gene analyses were performed for the genetic study of 661 patients. The patients were treated with individual intervention and long-term follow up. Prenatal diagnoses were carried out for 165 fetuses of the families. Results: Among 1 003 patients (580 boys and 423 girls), 296 cases (29.5%) had isolated methylmalonic acidemia; 707 cases (70.5%) had combined homocysteinemia; 59 patients (5.9%) were detected by newborn screening; 944 patients (94.1%) had the onset at the ages from several minutes after birth to 25 years and diagnosed at 3 days to 25 years of age. The main clinical presentations were psychomotor retardation and metabolic crisis. Multi-organ damage, including hematological abnormalities, pulmonary hypertension, kidney damage, were found. MMACHC, MUT, MMAA, MMAB, HCFC1, SUCLG1, SUCLA2 mutations were found in 631 patients (96.6%) out of 661 patients who accepted gene analysis. MMACHC mutations were detected in 460 patients (94.7%) out of 486 cases of methylmalonic acidemia combined with homocysteinemia. MUT mutations were found in 158 (90.3%) out of 169 cases of isolated methylmalonic acidemia. The development of 59 patients detected by newborn screening were normal; 918 cases (97.2%) were diagnosed after onset accepted the treatment. Forty-five of them completely recovered with normal development. Twenty-six patients (2.7%) died; 873 (92.5%) patients had mild to severe psychomotor retardation. Methylmalonic acidemia were found in 35 out of 165 fetuses by metabolites assay of amniotic fluid and amniocytes gene analysis. Conclusion Combined methylmalonic acidemia and homocysteinemia is the common type of methylmalonic acidemia in the mainland of China. CblC defect due to MMACHC mutations is the most common type of methylmalonic acidemia combined with homocysteinemia. MUT gene mutations are frequent in the patients with isolated methylmalonic acidemia. Newborn screening is key for the early diagnosis and the better outcome. Combined diagnosis of biochemical assays and gene analysis are reliable for the prenatal diagnosis of methylmalonic acidemia.

Objective To explore the clinical characteristics,gene mutations,diagnosis and treatment of chil-dren with dopa-responsive dystonia due to tyrosine hydroxylase(TH)deficiency.Methods Five patients(3 boys and 2 girls)with dopa-responsive dystonia due to TH deficiency were diagnosed and followed up from January 2002 to October 2017.The clinical manifestations,laboratory findings,treatment and TH gene mutations associated with TH defi-ciency were analyzed.Results Five patients came from different families.They had the onset at the age of 8 months to 20 months with dystonia,paroxysmal muscular hypertonia and normal intelligence or mild mental retardation.All of them had been misdiagnosed as cerebral palsy.Two cases with floppy limbs presented with fatigue and tremor.One case with floppy limbs presented with seizures. Complex heterozygous mutations were found in TH gene of all patients,which helped to confirm the diagnosis.Eight mutations were identified in TH gene.Six of them were reported.Two novel muta-tions,c.1077C>A(p.C359X)and c.1228C>T(p.R410C)were detected.After the treatment by levodopa[2.2-5.4 mg/(kg·d)],significant improvement was observed.Three patients recovered their intellectual and motor activi-ties.Two patients were dramatically improved but with slightly uncoordinated movements.Conclusion The patients of dopa-responsive dystonia due to TH deficiency usually have the onset around one year of age with almost normal inte-lligence,motor retardation and dystonia.The patients are likely misdiagnosed as cerebral palsy.The treatment with levo-dopa can dramatically improve the symptoms.The etiological diagnosis is very important.

Objective The neuronal ceroid lipofuscinosis (CLN are a group of severe lysosomal storage diseases.The patients present with clinically and genetically heterogeneous neurodegenerative disorders.This study aims to investigate the clinical characteristics and the gene mutations of a rare Chinese family with 3 siblings affected by CLN7.Methods The proband,a 5-year-old girl,visited us because of intermittently seizures and mental retardation for 2 years and a half in December,2015.Clinical investigation,brain magnetic resonance imaging(MRI),biochemical and the gene analysis were performed for the etiological study.Results The proband had seizures at the age of 2 and a half years,with the progressive motor deterioration,speech disturbance,mental regression and vision loss.Her brain MRI showed diffusive cerebral atrophy.The blood aminoacids,acylcarnitine and urine organic acid profiles were normal.Lysosomal palmitoyl protein thioesterase and tripeptidyl peptidase activities of peripheral leukocytes were normal.A compound heterozygous mutation of c.1351-1G ＞ A and c.300T ＞ G was detected on her MFSD8 gene,supporting the diagnosis of CLN7.Both of the 2 mutations were novel.Each of her parents carried one of the mutations.Two brothers of the proband had similar clinical process.Her elder brother died at the age of 7 due to severe encephalopathy of unknown etiology.The younger brother showed dyskinesia from the age of 2 years and seizures from the age of 4 years.A compound heterozygous mutation on MFSD8 gene,c.1351-1G ＞ A and c.300T ＞ G,was found from the younger brother,as same as the proband.Conclusions CLN7 is a rare disorder of CLN.In this study,the diagnosis of the 3 siblings with similar clinical process were much delayed.Gene analysis was key for the diagnosis.Two novel mutations were found on MFSD8 of the family.There is still no effective treatment for neurol ceroid lipofuscinosis.The prognosis is poor.Based on the mutation diagnosis,prenatal diagnosis for the next sibling is possible to the prevention of the disease.

Objective To investigate the effect of Miao medicine Jinwu Jiangu decoction containing serum freeze-dried powder on levels of IL-17,ACT1 and TRAF6 in human rheumatoid arthritis fibroblast like synoviocytes (RA-HFLS).Methods Rabbits were randomly divided into blank control group (recieving normal saline of the same volume),Jinwu Jiangu decoction high-dose,medium-dose and low-dose group (intragastrically administrated with Jinwu Jiangu decoction at doses of 14.4,4.8 and 2.4 g·kg-1,respectively),tripterygium glycosides group and prednisone group (treated with human equivalent dosage).RA-HFLS primary cell model was established in the experiment.ELISA method was used to detect effect of lyophilized powder on IL-17 secretion.Expression of ACT1,TRAF6 mRNA was detected by RT-PCR.Results Compared with the blank control gorup,IL-17 in the supernatant of each medication administration group was significantly decreased (all P<0.01),and it was decreased most significantly in Jinwu Jiangu decoction high-dose and medium-dose group.IL-17 was down-regulated more significantly in high-dose group than that in tripterygium glycosides group (P<0.01).Compared with the blank control group,TRAF6 and ACT1 mRNA expression level of each medication administration group were significantly decreased (all P<0.01),and in the high-dose group that were decreased most significantly,but not significantly different as compared with tripterygium glycosides group and prednisone group (P>0.05).Conclusion Freeze-dried powder of Jinwu Jiangu decoction can decrease the secretion of IL-17 and down-regulate expression of ACT1,TRAF6 with RA-HFLS.