OBJECTIVEArgininemia is a rare disorder of urea cycle defect. The clinical manifestations of this disorder are similar to those of cerebral palsy so that the diagnosis is usually much delayed. This study aimed to investigate the phenotypes and genotypes of seven Chinese patients suffering from argininemia.

METHODThree boys and four girls with spastic tetraplegia were diagnosed as argininemia by blood aminoacids analysis and ARG1 gene study. Patients were given a protein-restricted diet, citrulline, sodium benzoate, and other treatment intervention. The mother of Patient 5 and 6 accepted genetic counseling and underwent prenatal diagnosis by amniocentesis.

RESULTSeven patients presented with progressive spastic tetraplegia and poor physical growth from the age of 1 month to 4 years. Argininemia was found at the age of 1 year and 10 months to 12 years. Five patients had mental retardations. Three had seizures. Their blood arginine elevated (86.66 to 349.83 µmol/L, normal controls 5 to 25 µmol/L). Liver dysfunction was found in six patients. Five patients had elevated blood ammonia levels. In four patients, cerebral atrophy was observed by cranial magnetic resonance imaging. Nine mutations in the ARG1 gene were identified from 7 patients. Only two mutations, c.703G > A in exon 7 and c.32T > C in exon 1 had been reported. c.34G > T, c.53G > A, c.67delG, c.232dupG, c.374C > T, c.539G > C and c.646-649delCTCA, were novel mutations of ARG1. A homozygous mutation c.703G > A was found in the amniocytes of Patient 5's mother, indicating that the fetus was affected by argininemia. Induced abortion was performed. c.53G > A from Patient 6 was not found in the amniocytes of her mother, indicating that the fetus was not affected by hepatocyte arginase deficiency. The result was confirmed by postnatal mutation analysis of cord blood and the normal blood arginine of the newborn.

CONCLUSIONArgininemia is one of the few treatable causes of pediatric spastic paralysis. In this study, seven Chinese patients with spastic tetraplegia were detected by blood aminoacids analysis and confirmed by molecular analysis. Seven novel mutations on ARG1 gene were identified. Prenatal diagnosis of the fetus of a family was performed by amniocytes ARG1 gene analysis.

Abortion, Induced ; Amniocentesis ; Arginase ; Arginine ; blood ; Asian Continental Ancestry Group ; Child ; Child, Preschool ; DNA Mutational Analysis ; Diet, Protein-Restricted ; Exons ; Female ; Fetus ; Genotype ; Homozygote ; Humans ; Hyperammonemia ; diagnosis ; Hyperargininemia ; diagnosis ; physiopathology ; Infant ; Infant, Newborn ; Male ; Mutation ; Phenotype ; Pregnancy ; Prenatal Diagnosis ; Quadriplegia ; diagnosis ; physiopathology ; Seizures

OBJECTIVEWe report the first case of acute encephalopathy induced by vaccination in an infant with methylmalonic aciduria cblA in China.

METHODThe clinical presentation, blood acylcarnitines analysis, urine organic acids analysis and gene studies of the patient were summarized.

RESULTThe proband, a boy, was admitted at the age of 15 months because of recurrent vomiting, acidosis and development delay for 8 months. The previously healthy boy presented vomiting and coma just one hour after hepatitis B vaccination at the age of seven months. Moderate dehydration, electrolyte disturbance and metabolic acidosis had been found. Although his acute metabolic crisis had been corrected soon after intravenous transfusion, psychomotor retardation and recurrent vomiting had been observed. When he was 15 months old, vomiting and lethargy occurred again 3 hours after DTaP vaccination. He was weakened as the illness became worse and got coma with dyspnea 7 days later. He was hospitalized with the suspected diagnosis of viral encephalitis. Blood acylcarnitines analysis, urine organic acids analysis and gene study had been performed for the etiologic investigation.His blood propionylcarnitine (16.3 µmol/L vs. normal range 1.0-5.0 µmol/L) and propionylcarnitine/free carnitine ratio (0.27 vs. normal range 0.03 to 0.25) increased. Markedly elevated urinary methylmalonic acid (388.21 mmol/mol creatinine vs. normal range 0.2 to 3.6 mmol/mol creatinine) and normal plasma total homocysteine supported the diagnosis of isolated methylmalonic aciduria. Two mutations, c.650 T>A (p.L217X) and c.742 C>T (p.Q248X), were identified in his MMAA gene, confirmed the diagnosis of cblA. Each parent carried one of the two mutations. Progressive clinical and biochemical improvement has been observed after hydroxylcobalamin injection, protein-restricted diet with the supplements of special formula and L-carnitine. He is currently 2 years and 7 months old with normal development and general condition.

CONCLUSIONA boy with cblA was firstly detected after the acute encephalopathy induced by vaccination in China. It is important to pay more attention to the patients with metabolic crisis or organ damage after vaccination. Metabolic studies are keys to the diagnosis of potential diseases and improve the outcome.

Amino Acid Metabolism, Inborn Errors ; complications ; Brain Diseases ; chemically induced ; Carnitine ; analogs & derivatives ; Diet, Protein-Restricted ; Hepatitis B Vaccines ; adverse effects ; Humans ; Infant ; Male ; Methylmalonic Acid ; urine ; Mutation ; Vaccination ; adverse effects ; Vitamin B Complex ; Vomiting

OBJECTIVETo investigate the clinical, biochemical and genetic profiles of 28 Chinese patients with glutaric aciduria type 1.

METHODTwenty-eight patients with glutaric aciduria type 1 seen in the Department of Pediatrics, Peking University First Hospital from July 2003 to October 2013 were studied. The data of clinical course, laboratory examinations, cranial MRI and GCDH gene mutations of the patients were analyzed.

RESULT(1) Three cases were detected by newborn screening, and the other patients were diagnosed at the age of 2 months to 17 years. (2) 22 patients (79%) were infant onset cases with psychomotor retardation, dystonia, seizures, athetosis, recurrent vomiting, drowsiness or feeding difficulty. Only two of the 22 patients with infant onset got normal intelligence and movement after treatment. Twenty of them were improved slowly with delayed development, dystonia and other neurological problems. Three patients (11%) had late onset. They had motor regression, headache and seizure at the age of 8, 9 and 17 years, respectively. Rapid improvement was observed after treatment. (3) Cranial MRI has been checked in 23 patients; 22 of them showed characteristic widening of the Sylvian fissure, abnormalities of the basal ganglia, leukoencephalopathy and brain atrophy. Thirty-five mutations in GCDH gene of the patients were identified; c.148T>C (p.W50R) was the most common mutation with the frequency of 7.7%; 6 mutations (c.628A>G, c.700C>T, c.731G>T, c.963G>C, c.1031C>T and c.1109T>C) were novel.

CONCLUSIONGlutaric aciduria type 1 usually induced neurological deterioration resulting in severe psychomotor retardation and dystonia. Most of our patients were clinically diagnosed. Patients with early onset usually remained having neurological damage. Phenotype and genotype correlation has not been found in the patients. Neonatal screening for organic acidurias should be expanded in China.

Age of Onset ; Amino Acid Metabolism, Inborn Errors ; diagnosis ; genetics ; metabolism ; Brain Diseases, Metabolic ; diagnosis ; genetics ; metabolism ; DNA Mutational Analysis ; Follow-Up Studies ; Gas Chromatography-Mass Spectrometry ; Glutarates ; urine ; Glutaryl-CoA Dehydrogenase ; deficiency ; genetics ; metabolism ; Humans ; Infant, Newborn ; Intellectual Disability ; etiology ; pathology ; Magnetic Resonance Imaging ; Movement Disorders ; etiology ; pathology ; Mutation ; Neonatal Screening ; methods ; Retrospective Studies

OBJECTIVETo investigate the phenotype and genotype of a Chinese boy and his family affected by infantile Sandhoff disease.

METHODSThe proband, a boy, was the first child born to a non-consanguineous couple. He showed startle reaction after birth and progressive psychomotor regression from the age of 8 months. From the age of 16 months, he presented seizures. When he was admitted at 17 months old, severe mental retardation and weakness were observed. Fundus examination revealed bilateral cherry-red spots in the macula and optic atrophy. Cranial MRI revealed abnormal signals in the thalamus, basal ganglia and white matter. Enzymatic assay and genetic testing were performed for the diagnosis. His mother visited us at 18 weeks of pregnancy seeking for prenatal diagnosis. HEXB gene diagnosis to the fetus was performed by direct sequencing.

RESULTSSignificant deficient total β-hexosaminidase (A and B) activity in peripheral leucocytes of the patient (0.0 nmol/h/mg compared with normal control, 41.9 to 135.1 nmol/h/mg) supported the diagnosis of Sandhoff disease. On his HEXB gene, two mutations were found. c.1645G-A (p.G549R) was novel. c.IVS7-48T was a reported mutation. Now, the patient was 2 years and 3 months old, with progressive general failure, severe epilepsy, blindness and hypermyotonia. Subsequently, the mother visited us at 18 weeks of pregnancy seeking for prenatal diagnosis. HEXB gene analysis of the amniocytes was performed by direct sequencing. Both of the two mutations were not detected from cultured amniocytes. The result revealed that the fetus was not affected by Sandhoff disease. A healthy girl, the sibling of the proband, was born in term. Postnatal enzyme analysis and genetic analysis of the cord blood cells confirmed the prenatal diagnosis.

CONCLUSIONOne novel mutation on HEXB gene was identified. Prenatal diagnosis to the fetus of this family was performed by amniocytes gene analysis.

Adult ; Amniotic Fluid ; cytology ; Child, Preschool ; DNA Mutational Analysis ; Female ; Genetic Testing ; Humans ; Male ; Mutation ; Pregnancy ; Prenatal Diagnosis ; Sandhoff Disease ; diagnosis ; genetics ; beta-Hexosaminidase beta Chain ; genetics