Objectives The combined use of bedaquiline and delamanid(BDQ-DLM)is limited by an increased risk of prolonging the QTc interval.We retrospectively evaluated patients who received DLM/BDQ-containing regimens at a TB-specialized hospital.We aimed to present clinical efficacy and safety data for Chinese patients. Methods This case-control study included patients with multidrug-resistant tuberculosis(MDR-TB)treated with BDQ alone or BDQ plus DLM. Results A total of 96 patients were included in this analysis:64 in the BDQ group and 32 in the BDQ+DLM group.Among the 96 patients with positive sputum culture at the initiation of BDQ alone or BDQ combined with DLM,46 patients(71.9%)in the BDQ group and 29(90.6%)in the BDQ-DLM group achieved sputum culture conversion during treatment.The rate of sputum culture conversion did not differ between the two groups.The time to sputum culture conversion was significantly shorter in the BDQ-DLM group than in the BDQ group.The most frequent adverse event was QTc interval prolongation;however,the frequency of adverse events did not differ between the groups. Conclusion In conclusion,our results demonstrate that the combined use of BDQ and DLM is efficacious and tolerable in Chinese patients infected with MDR-TB.Patients in the BDQ-DLM group achieved sputum culture conversion sooner than those in the BDQ group.

Objective:To explore the diagnosis and treatment of adolescence-onset methylenetetrahydrofolate reductase (MTHFR) deficiency.Methods:This was a retrospective case study. Nine patients with adolescence-onset MTHFR deficiency were diagnosed at Peking University First Hospital from January 2016 to December 2022, and followed up for more than 1 year. Their general information, clinical manifestations, laboratory tests, cranial images, MTHFR gene variants, diagnosis, treatment, and outcome were analyzed retrospectively.Results:The 9 patients came from 8 families. They had symptoms at age of 8.0 years to 17.0 years and diagnosed at 9.0 years to 17.5 years. Eight were male and 1 was female. Two patients were brothers, the elder brother developed abnormal gait at 17.0 years; and the younger brother was then diagnosed at 15.0 years of age and treated at the asymptomatic stage, who was 18.0 years old with normal condition during this study. The main manifestations of the 8 symptomatic patients included progressive dyskinesia and spastic paralysis of the lower limbs, with or without intellectual decline, cognitive impairment and behavioral abnormalities. Totally, 15 variants of MTHFR gene were identified in the 9 patients, including 8 novel variants. Five patients had brain image abnormalities. Increased plasma total homocysteine level (65-221 μmol/L) was found in all patients, and decreased to 20-70 μmol/L after treatment with betaine and calcium folinate. Besides, the 8 symptomatic patients had their behavior and cognitive problems significantly improved, with a legacy of lower limb motor disorders.Conclusions:Late-onset MTHFR deficiency can occur in adolescence. The diagnosis is usually delayed because of non-specific clinical symptoms. The test of blood total homocysteine could be used as a selective screening test. Eight novel varients of MTHFR gene were identified. Timely treatment can improve clinical condition significantly, and pre-symptomatic treatment may prevent brain damage.

Objective:To investigate the clinical features and outcomes of adolescence-onset methylmalonic acidemia (MMA) and explore preventive strategies.Methods:This was a retrospective case analysis of the phenotypes, genotypes and prognoses of adolescence-onset MMA patients. There were 55 patients diagnosed in Peking University First Hospital from January 2002 to June 2023, the data of symptoms, signs, laboratory results, gene variations, and outcomes was collected. The follow-ups were done through WeChat, telephone, or clinic visits every 3 to 6 months.Results:Among the 55 patients, 31 were males and 24 were females. The age of onset was 12 years old (range 10-18 years old). They visited clinics at Tanner stages 2 to 5 with typical secondary sexual characteristics. Nine cases (16%) were trigged by infection and 5 cases (9%) were triggered by insidious exercises. The period from onset to diagnosis was between 2 months and 6 years. Forty-five cases (82%) had neuropsychiatric symptoms as the main symptoms, followed by cardiovascular symptoms in 12 cases (22%), kidney damage in 7 cases (13%), and eye disease in 12 cases (22%). Fifty-four cases (98%) had the biochemical characteristics of methylmalonic acidemia combined with homocysteinemia, and 1 case (2%) had the isolated methylmalonic acidemia. Genetic diagnosis was obtained in 54 cases, with 20 variants identified in MMACHC gene and 2 in MMUT gene. In 53 children with MMACHC gene mutation,1 case had dual gene variants of PRDX1 and MMACHC, with 105 alleles. The top 5 frequent variants in MMACHC were c.482G>A in 39 alleles (37%), c.609G>A in 17 alleles (16%), c.658_660delAAG in 11 alleles (10%), c.80A>G in 10 alleles (10%), c.567dupT and c.394C>T both are 4 alleles (4%). All patients recovered using cobalamin, L-carnitine, betaine, and symptomatic therapy, and 54 patients (98%) returned to school or work.Conclusions:Patients with adolescence-onset MMA may triggered by fatigue or infection. The diagnosis is often delayed due to non-specific symptoms. Metabolic and genetic tests are crucial for a definite diagnosis. Treatment with cobalamin, L-carnitine, and betaine can effectively reverse the prognosis of MMA in adolescence-onset patients.

CRISPR-Associated Protein 9 ; Gene Editing ; CRISPR-Cas Systems/genetics*

Objective:To analyze the MRI characteristics of surgical resected renal angiomyolipoma (AML) smaller than 4 cm.Methods:A total of 112 patients with surgical pathology confirmed renal AML of which the maximum diameter was smaller than 4 cm were analyzed retrospectively in the First Medical Centre, Chinese PLA General Hospital from January 2014 to November 2020, 5 of which were epithelioid angiomyolipoma (EAML) patients. According to the presence or absence of visible fat in lesions on MRI, the lesions were divided into AML with fat group and AML without visible fat (AML wovf) group. The MRI features were evaluated, including maximum diameter, location, growth pattern, shape, beak sign, angular interface with renal parenchyma, pseudo-capsule, hemorrhage, cystic degeneration, coagulative necrosis, flowing void in the tumor, signal intensity and homogeneity on T 2WI and diffusion weighter imaging (DWI), the peak enhanced phase. The differences of maximum diameter of AML with fat and AML wovf were analyzed using Mann-Whitney U test, and the differences of MRI features were analyzed using χ 2 test or Fisher′s exact probability test. Results:There were 123 lesions found in 112 patients, and 96 lesions contained fat and 27 lesions were AML wovf. 82 lesions showed round and round-like shapes, 112 lesions showed exophytic growth pattern, 71 lesions with peak enhancement in corticomedullary phase. And the numbers of lesions with angular interface with renal parenchyma, beak sign, cystic degeneration, pseudo-capsule, hemorrhage were 30, 49, 1, 1, 1, respectively. There was no coagulative necrosis in all lesions. Compared with AML with fat, AML wovf was single lesion. The diameters of AML with fat and AML wovf were 2.5 (1.7, 3.5) and 1.8 (1.4, 2.3) cm respectively, with statistically significant difference ( Z=-2.80, P=0.005). In the AML with fat and AML wovf, 65 and 12 cases were heterogeneous in T 2WI, 44 and 5 lesions showed beak sign, 26 and 4 lesions showed angular interface with renal parenchyma, 57 and 10 cases were heterogeneous in DWI. And there were 5 and 6 lesions showed the endophytic, 44 and 8 lesions showed partly exophytic, 47 and 13 lesions showed exophytic in patterns of tumor growth respectively. The beak sign, homogeneous in T 2WI and DWI, patterns of tumor growth showed statistical differences in AML with fat and AML wovf (all P<0.05), and there was no significant difference in other features ( P>0.05). A total of 5 EAML patients were with 8 lesions. One patient had 4 lesions with fat, other patients had single lesion in which 2 lesions with fat, 2 lesions without visible fat. One lesion without visible fat showed hemorrhage. Conclusions:Surgical resected AML smaller than 4 cm is often exophytic round and round-like, enhanced in corticomedullary phase, showing angular interface with renal parenchyma and beak sign, with rare cystic degeneration, pseudo-capsule, hemorrhage and improbable coagulation necrosis. AML wovf is single smaller lesion which often shows endophytic growth pattern, and beak sign is infrequent. EAML seems to be present in two modes, multiple lesions with fat and AML wovf with hemorrhage.

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 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.