Multiple carboxylase deficiency (MCD) includes autosomal recessive holocarboxylase synthetase (HLCS) deficiency and biotinidase (BTD) deficiency, which are caused by and gene mutations respectively. Neonatal screening for HLCS deficiency is based on 3-hydroxyisovaleryl carnitine in dry blood filter paper, and BTD deficiency is based on BTD activity determination. HLCS deficiency and BTD deficiency are characterized by neurocutaneous syndrome and organic aciduria, however, they are different in onset age, neurological symptoms and metabolic decompensation, which needed to be differentiated from acquired biotin deficiency or other genetic metabolic diseases. The diagnosis of the disease requires a combination of biochemical characteristics of hematuria, enzyme activity determination and genetic test. Routine biotin doses are effective for most MCD patients. This consensus is intended to benefit early screening and diagnosis of MCD.
Biotin/therapeutic use* ; Biotinidase Deficiency/therapy* ; Carbon-Nitrogen Ligases/metabolism* ; Consensus ; Holocarboxylase Synthetase Deficiency/genetics* ; Humans ; Infant, Newborn ; Multiple Carboxylase Deficiency/drug therapy* ; Neonatal Screening

OBJECTIVETo confirm the diagnosis of multiple carboxylase deficiency (MCD) on the gene level and explore the mutations in Chinese children with MCD.

METHODSBiotinidase (BT) and holocarboxylase synthetase (HLCS) genes were analyzed by PCR and direct sequencing for the 4 BT deficiency patients and 8 HLCS deficiency patients, respectively. The identified mutations in the parents of the patients and 50 normal controls were screened by PCR-restriction fragment length polymorphism and direct DNA sequencing.

RESULTSTotal detection rate of gene mutation is 100% in the 12 children with MCD. Six mutations were detected in the 4 children with BT deficiency, they were c. 98-104del7ins3, c. 1369G>A (V457M), c. 1157G>A(W386X), c. 1284C>A(Y428X), c. 1384delA and c. 1493_1494insT. The last four were novel mutations. Four mutations were found in the 8 children with HLCS deficiency. They were c. 126G>T (E42D), c. 1994G>C (R665P), c. 1088T>A (V363D) and c. 1522C>T (R508W). The last two were hot-spot mutations [75%(12/16)], and c. 1994G>C (R665P) was a novel mutation.

CONCLUSIONThis study confirmed the diagnosis of 12 patients with MCD on the gene level. Six mutations were found in the BT gene and 4 in the HLCS gene, including 5 novel mutations. Two mutations of the HLCS gene are probably hot-spot mutations in Chinese children with HLCS deficiency.

Asian Continental Ancestry Group ; genetics ; Base Sequence ; Biotinidase ; genetics ; Biotinidase Deficiency ; Carbon-Nitrogen Ligases ; deficiency ; genetics ; Case-Control Studies ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Male ; Molecular Sequence Data ; Multiple Carboxylase Deficiency ; genetics ; metabolism ; Mutation

PURPOSE: Seizure associated with fever may indicate the presence of underlying inherited metabolic diseases. The present study was performed to investigate the presence of underlying metabolic diseases in patients with complex febrile seizures, using analyses of urine organic acids. METHODS: We retrospectively analyzed and compared the results of urine organic acid analysis with routine laboratory findings in 278 patients referred for complex febrile seizure. RESULTS: Of 278 patients, 132 had no abnormal laboratory findings, and 146 patients had at least one of the following abnormal laboratory findings: acidosis (n=58), hyperammonemia (n=55), hypoglycemia (n=21), ketosis (n=12). Twenty-six (19.7%) of the 132 patients with no abnormal findings and 104 (71.2%) of the 146 patients with statistically significant abnormalities showed abnormalities on the organic acid analysis (P<0.05). Mitochondrial respiratory chain disorders (n=23) were the most common diseases found in the normal routine laboratory group, followed by PDH deficiency (n=2 ) and ketolytic defect (n=1). In the abnormal routine laboratory group, mitochondrial respiratory chain disorder (n=29) was the most common disease, followed by ketolytic defects (n=27), PDH deficiency (n=9), glutaric aciduria type II (n=9), 3-methylglutaconic aciduria type III (n=6), biotinidase deficiency (n=5), propionic acidemia (n=4), methylmalonic acidemia (n=2), 3-hydroxyisobutyric aciduria (n=2), orotic aciduria (n=2), fatty acid oxidation disorders (n=2), 2-methylbranched chain acyl CoA dehydrogenase deficiency (n=2), 3-methylglutaconic aciduria type I (n=1), maple syrup urine disease (n=1), isovaleric acidemia (n=1), HMG-CoA lyase deficiency (n=1), L-2-hydroxyglutaric aciduria (n=1), and pyruvate carboxylase deficiency (n=1). CONCLUSION: These findings suggest that urine organic acid analysis should be performed in all patients with complex febrile seizure and other risk factors for early detection of inherited metabolic diseases.
Acetyl-CoA C-Acetyltransferase ; Acidosis ; Acyl-CoA Dehydrogenase ; Amino Acid Metabolism, Inborn Errors ; Biotinidase Deficiency ; Brain Diseases, Metabolic, Inborn ; Electron Transport ; Fever ; Humans ; Hydroxybutyrates ; Hyperammonemia ; Hypoglycemia ; Isovaleryl-CoA Dehydrogenase ; Ketosis ; Maple Syrup Urine Disease ; Metabolic Diseases ; Multiple Acyl Coenzyme A Dehydrogenase Deficiency ; Propionic Acidemia ; Pyruvate Carboxylase Deficiency Disease ; Pyruvate Dehydrogenase Complex Deficiency Disease ; Retrospective Studies ; Risk Factors ; Seizures ; Seizures, Febrile

OBJECTIVEMultiple carboxylase deficiency (MCD) is an autosomal recessive disorder. MCD is characterized by skin rash, metabolic acidosis, vomiting and psychomotor retardation. Depending on deficiency of the enzyme, MCD includes two different forms, biotinidase deficiency (BTD, OMIM 253260) and holocarboxylase synthetase deficiency (HLCSD, OMIM 253270). In this study, we analyzed gene mutations of four Chinese MCD patients and to explore the mutation spectrum and possibility of a molecular diagnosis.

METHODSAll exons and their flanking introns of biotinidase gene and HLCS gene were screened by polymerase chain reaction combined with DNA direct sequencing in four Chinese MCD patients. Genomic DNA was extracted using a kit from the peripheral blood leukocytes of each patient. PCR amplification products were checked by 2% agarose gel electrophoresis and were subsequently sequenced with both the forward and reverse primers.

RESULTSAll patients showed mutations in HLCS gene, whereas no mutation was found in biotinidase gene, proving that all the four patients had HLCS deficiency. Four previously reported mutations in HLCS gene were detected (Y456C, R508W, D634N and 780delG). A missense mutation of 1522C > T in exon 11 of HLCS gene, which was a homozygotic mutation, was identified in patient 1; a mutation of 1522C > T in exon 11 combined with a mutation of 1367A > G in exon 9, which was a compound heterozygotic mutation, was identified in patient 2; a mutation of 1522C > T in exon 11 combined with a mutation of 1900G > A in exon 13, which was a compound heterozygotic mutation, was identified in patient 3; a mutation of 1522C > T in exon 11 combined with a mutation of 780delG in exon 7, which was a compound heterozygotic mutation, was identified in patient 4. All the parents were carriers of mutations. No additional carrier of this four mutations was identified from 50 samples of Chinese controls.

CONCLUSIONThe 1522C > T (R508W) mutation probably represents a mutational hot-spot in Chinese HLCS deficiency patients while the 780delG mutation which was reported only in Japanese patients was found firstly in Chinese patients.

Asian Continental Ancestry Group ; genetics ; Biotinidase ; genetics ; Carbon-Nitrogen Ligases ; genetics ; DNA Mutational Analysis ; Exons ; Female ; Holocarboxylase Synthetase Deficiency ; enzymology ; genetics ; Humans ; Infant ; Infant, Newborn ; Introns ; Male

OBJECTIVETo report the clinical diagnosis, treatment and follow-up of children with holocarboxylase synthetas(HCS) deficiency and explore the gene mutation spectrum of the disease.

METHODSEleven children with HCS deficiency were enrolled. Mass spectrometry analysis and biotinidase activity determination were used for diagnosis of HCS deficiency. HCS gene mutations were analyzed by PCR directed sequencing methods. Ten patients received oral biotin treatment (10-40 mg/d). Clinical effects of biotin treatment were observed.

RESULTSAll 11 cases developed apathetic, lethargy and metabolic acidosis at different degrees, and 10 cases presented with skin lesions. The average blood 3-hydroxyisovaleryl-carnitine concentrations and urinary 3-methylcrontonylglycine and methylcitrate concentrations increased significantly. The biotinidase activity increased, being higher over 30% of the normal reference value. Four mutations in HCS gene were identified, and they were c.1522C>T (R508W), c.1088T>A (V363D), c.126G>T (E42D) and c.1994G>C (R665P) (a new variant) and the frequency was 50%, 29%, 7% and 14% respectively. The symptoms disappeared in 10 cases 1-2 weeks after biotin treatment, and blood and urinary abnormal metabolites were gradually reduced to normal 2-6 months after treatment.

CONCLUSIONSHCS deficiency is characterized by nervous system damage, skin lesions and metabolic acidosis. Mass spectrometry analysis, biotinidase activity determination and gene mutation analysis may be helpful in the definite diagnosis of this disorder. The effect of early biotin treatment is satisfactory. The mutations R508W and V363D might be hot-spots in Chinese children with HCS deficiency.

Biotin ; therapeutic use ; Biotinidase ; metabolism ; Carbon-Nitrogen Ligases ; genetics ; Child, Preschool ; Female ; Holocarboxylase Synthetase Deficiency ; diagnosis ; therapy ; Humans ; Infant ; Infant, Newborn ; Male ; Mutation

OBJECTIVE: To explore the genetic basis for a patient featuring multiple carboxylase deficiency (MCD). METHODS: PCR and Sanger sequencing were used to detect variant in the coding region of BT and HLCS genes in the patient. Suspected variants were verified in her parents and 80 unrelated healthy controls by a PCR-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: The patient was found to carry compound heterozygous variants of the HLCS gene, namely c.286delG (p.Val96Leufs*162) and c.1648G>A (p.Val550Met). The c.286delG (p.Val96Leufs*162) was verified to be novel variant based on the result of PCR-RFLP analysis. No variant was found in the coding regions of BT gene in the patient. CONCLUSION The compound c.286delG (p.Val96Leufs*162) and c.1648G>A (p.Val550Met) variants probably underlie the MCD disorder in this patient. Above results have enriched the variant spectrum of MCA.
Carbon-Nitrogen Ligases ; genetics ; Exons ; Female ; Humans ; Multiple Carboxylase Deficiency ; genetics ; Mutation ; Open Reading Frames ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Sequence Analysis, DNA

A boy, aged 16 months, attended the hospital due to head and facial erythema for 15 months and vulva erythema for 10 months with aggravation for 5 days. The boy developed perioral and periocular erythema in the neonatal period and had erythema and papules with desquamation and erosion in the neck, armpit, and trigone of vulva in infancy. Blood gas analysis showed metabolic acidosis; the analysis of amino acid and acylcarnitine profiles for inherited metabolic diseases and the analysis of organic acid in urine suggested multiple carboxylase deficiency; genetic testing showed a homozygous mutation of c.1522C>T(p.R508W) in the HLCS gene. Finally the boy was diagnosed with holocarboxylase synthetase deficiency and achieved a good clinical outcome after oral biotin treatment. This article analyzes the clinical data of a child with holocarboxylase synthetase deficiency and summarizes the etiology, diagnosis, and treatment of this child, so as to provide ideas for clinicians to diagnose this rare disease.
Humans ; Male ; Biotin/therapeutic use* ; Holocarboxylase Synthetase Deficiency/drug therapy* ; Homozygote ; Mutation ; Rare Diseases/drug therapy* ; Infant

Biotinidase deficiency is a disorder inherited autosomal recessively showing evidence of hearing loss and optic atrophy in addition to seizures, hypotonia, and ataxia. In the present study, a 2-year-old boy with Biotinidase deficiency is presented in which clinical symptoms have been reported with auditory neuropathy/auditory dyssynchrony (AN/AD). In this case, transient-evoked otoacoustic emissions showed bilaterally normal responses representing normal function of outer hair cells. In contrast, acoustic reflex test showed absent reflexes bilaterally, and visual reinforcement audiometry and auditory brainstem responses indicated severe to profound hearing loss in both ears. These results suggest AN/AD in patients with Biotinidase deficiency.
Ataxia ; Audiometry ; Biotinidase Deficiency* ; Biotinidase* ; Child, Preschool ; Ear ; Evoked Potentials, Auditory, Brain Stem ; Hair ; Hearing Loss ; Humans ; Male ; Muscle Hypotonia ; Optic Atrophy ; Reflex, Abnormal ; Reflex, Acoustic ; Seizures

OBJECTIVETo investigate the clinical and neurodevelopmental profiles of patients with biotinidase deficiency and to determine the efficacy of current therapy with respect to outcome.

METHODSSix patients aged from 3 months to 14 years with biotinidase deficiency were confirmed by urinary organic acid analysis with gas chromatography/mass spectrometry (GC/MS) and biotinidase assay on dried blood spots. Biotin was supplemented individually (10-40 mg/d). Their clinical features, laboratory findings, and treatment regimen were reviewed.

RESULTSAll the 6 patients presented with some extent of neurological abnormalities and dermatological lesions. Cases 1 - 3 had poor feeding, vomiting, seizures, mental retardation, and lethargy onset from their early infancy, with varied degree of anemia, ketosis, acidosis, and hypoglycemia. Case 2 exhibited eczema and dermatitis from his age of 7 months. Case 4 displayed motor deficit and ataxia after 6 months of age, and generalized pustular psoriasis when he was 8 months old. Cases 5 and 6 gradually showed muscle weakness and paraplegia at the age of 7 years and 5 years, respectively. Inflammatory demyelination changes of cervical cord were evident on magnetic resonance imaging in these two patients. Case 6 had progressive optic atrophy, eczema and alopecia. Remarkable elevations of urinary lactate, pyruvate, 3-OH-propionate, methylcitrate, propionylglycine, 3-OH-isovalerate, 3-methylcrontonylglycine were confirmed in cases 1, 2, 3 and 5. Slight increase of urinary lactate, pyruvate, and 3-methylcrontonylglycine was observed in cases 4 and 6. Biotinidase activities assayed on dried blood spots from all the patients were below 0.1 pmol/(min.3 mm) Biotin supplementation for all the patients, except for case 3 who was not treated, resulted in pronounced and rapid clinical and biochemical improvement. Cases 4 and 6 had residual neurological damage comprising ataxia and motor handicap of legs, due to prolonged disease course.

CONCLUSIONSBiotinidase deficiency intensively impairs nervous system and skin in the affected patients. Urinary organic acid analysis and blood biotinidase assay are crucial to the diagnosis. Early diagnosis and biotin supplementation can contribute significantly to the improvement of prognosis.

Adolescent ; Biotin ; administration & dosage ; therapeutic use ; Biotinidase Deficiency ; diagnosis ; drug therapy ; urine ; Child ; Child, Preschool ; Gas Chromatography-Mass Spectrometry ; Humans ; Infant ; Male ; Treatment Outcome

PURPOSE: We have done this retrospective study to know the relative incidence and clinical manifestations of organic acidopathies in Korea during 8 years(from Jul. 1997 to May 2005). This results of organic acid analysis of 1,787 patients were compared with the results of organic acid analysis that were published three years ago. METHODS: The results of quantitative organic acid analysis of samples of 1788 patients, referred from Jul. 1997 to May 2005, were analyzed retrospectively according to four age group(-2 mon, 3 mon-2 years, 3-12 years) and major clinical manifestations. Quantification of 83 organic acids was done with gas chromatography and mass spectometry. RESULTS: We diagnosed 470 patients with 27 diseases of organic acid metabolism during this study period. Diseases found more than 10 cases are cytosolic 3-ketothiolase deficiency, mitochondrial respiratory chain disorders, PDHC deficiency, mitochondrial 3-ketothiolase deficiency, glutaric aciduria type II, biotinidase deficiency, methylmalonic aciduria and propionic aciduria. Other diseases were diagnosed in less than 10 cases. CONCLUSION: Though the incidence of individual organic acidemia is low, the overall incidence of organic acidemia as a whole seems to be relatively high in Korea. Compared with the results of organic acid analysis that were reported three years ago, we couldn't find a new disease and the difference of the relative incidences of high incident diseases. We were apprehensive of the errors that was owing to the short study period(3 years), but the relative incidences of our study(8 years) were similar to the results of organic acid analysis that were reported three years ago.
Acetyl-CoA C-Acyltransferase ; Biotinidase Deficiency ; Chromatography, Gas ; Cytosol ; Electron Transport ; Humans ; Incidence ; Korea* ; Metabolism ; Multiple Acyl Coenzyme A Dehydrogenase Deficiency ; Neurologic Manifestations ; Propionic Acidemia ; Pyruvate Dehydrogenase Complex Deficiency Disease ; Retrospective Studies