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Methylmalonic acidemia (MMA) is an inherited metabolic disease. In this condition, metabolism from methylmalonyl coenzyme A (CoA) to succinyl-CoA is inhibited because of either low methylmalonyl-CoA mutase (MCM) activity or adenosylcobalamin deficiency owing to altered vitamin B12 metabolism. A high-precision assay for detecting MCM activity would facilitate not only MMA diagnosis but also the ability to determine the severity of MMA. We developed an MCM assay method based on ultrahigh-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) that involves the determination of succinyl-CoA, which is formed in an enzyme reaction, using peripheral lymphocytes. Using 0.05, 0.5, and 5 μmol/L succinyl-CoA, the intra-assay coefficient of variation (CV) was less than 5.2 % and the inter-assay CV was less than 8.7 %. The MCM activities of five healthy individuals and four patients were investigated with this assay. The MCM activities of the patients were very low in relation to those of healthy individuals. Together, these results show that the UPLC–MS/MS method is useful for a detailed MCM activity assay.

Propionic acidemia (PA) is an inherited metabolic disease caused by low activity of propionyl coenzyme A (CoA) carboxylase (PCC), which metabolizes propionyl-CoA into methylmalonyl-CoA. Although many patients with PA have been identified by tandem mass spectrometry since the test was first included in neonatal mass screening in the 1990s, the disease severity varies. Thus, determining the specific level of PCC activity is considered to be helpful to grasp the severity of PA. We developed a new PCC assay method by the determination of methylmalonyl-CoA, which is formed by an enzyme reaction using peripheral lymphocytes, based on ultra high-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). With methylmalonyl-CoA concentrations of 0.05, 0.5, and 5μmol/L, the intra-assay coefficients of variation (CVs) were 8.2%, 8.7%, and 5.1%, respectively, and the inter-assay CVs were 13.6%, 10.5%, and 5.9%, respectively. The PCC activities of 20 healthy individuals and 6 PA patients were investigated with this assay. Methylmalonyl-CoA was not detected in one PA patient with a severe form of the disease, but the remaining PA patients with mild disease showed residual activities (3.3-7.8%). These results demonstrate that determination of PCC activity with this assay would be useful to distinguish between mild and severe cases of PA to help choose an appropriate treatment plan.

Tandem mass spectrometry (MS/MS) has become a prominent method for screening newborns for diseases such as organic acidemia and fatty acid oxidation defects, although current methods cannot separate acylcarnitine isomers. Accurate determination of dicarboxylic acylcarnitines such as methylmalonylcarnitine and glutarylcarnitine has not been carried out, because obtaining standards of these acylcarnitines is difficult. We attempted the individual determinations of acylcarnitines with isomers and dicarboxylic acylcarnitines by applying high-performance liquid chromatography (HPLC). Chromatographic separation was performed by gradient elution using a mixture of 0.08% aqueous ion-pairing agent and acetonitrile as the mobile phase. Mass transitions of m/z 161.8--84.8 for carnitine and m/z 164.8--84.8 for deuterated carnitine were monitored in positive ion electrospray ionization mode. One carnitine and 16 acylcarnitines were quantified. The limit of quantitation (LOQ) was 0.1 micromol/L for methylmalonylcarnitine and 0.05 micromol/L for the other acylcarnitines. Intra-day and inter-day coefficients of variance (CVs) were8.3% and8.8%, respectively, for all acylcarnitines in serum, and both were9.2% in urine. Mean recoveries were90% for all acylcarnitines. Human samples were quantified by this method. After addition of deuterated acylcarnitines as internal standards, acylcarnitines in serum or urine were extracted using a solid-phase extraction cartridge. In healthy adult individuals, isobutyryl-, 2-methylbutyryl- and isovalerylcarnitine were detected in serum and urine. Dicarboxylic acylcarnitines were detected in urine. High concentrations of methylmalonylcarnitine and propionylcarnitine were found in both the serum and the urine of a patient with methylmalonic acidemia. The described HPLC/MS/MS method could separate most acylcarnitine isomers and quantify them, potentially allowing detailed diagnoses and follow-up treatment for those diseases.

Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is rare among Asian individuals, and the clinical course and biochemical findings remain unclear. We report herein a 3-year-old Japanese girl with MCADD. The diagnosis was suggested by acylcarnitine profiles and confirmed by enzyme activity and genetic analysis after clinical presentation. Our described method with high-performance liquid chromatography/tandem mass spectrometry allows quantification of levels of n-octanoylcarnitine (C8-N) and other isomers (e.g. valproylcarnitine). We examined the patient's acylcarnitine profiles in serum and urine samples during carnitine loading and 14-hr fasting tests with/without carnitine supplementation. Under hypocarnitinemia, serum level of C8-N was 0.16 micromol/l and C8-N/decanoylcarnitine (C10) ratio was 1.8, which did not correspond to the diagnostic criteria for MCADD. However, intravenous carnitine loading test (100 mg/kg/day for 3 days and 50 mg/kg/day for 1 day) led to increased serum C8-N levels and urinary excretion was obvious, strongly suggesting MCADD. In the fasting test with carnitine supplementation, marked production of acylcarnitines (C8-N > C2 >> C6 > C10) was found, compared to the fasting test without carnitine supplementation. These results indicate that carnitine supplementation may be useful for detoxification of accumulated acylcarnitines even in an asymptomatic state. Moreover, the one-point examination for serum C8-N level and/or C8-N/C10 ratio may make the diagnosis of MCADD difficult, particularly in the presence of significant hypocarnitinemia. To avoid this pitfall, attention should be given to serum levels of free carnitine, and carnitine loading may be demanded in hypocarnitinemia.

We encountered a case with long-term remission of Cushing's disease due to pituitary apoplexy. The apoplexy of pituitary adenoma secreting adrenocorticotropin hormone was diagnosed by successive and timely magnetic resonance imaging when the symptoms of the patient were not yet severe and anterior pituitary dysfunction was only a transient reduction of growth hormone secretion. Seven years after the first episode of pituitary apoplexy, hypercorticism recurred, and pituitary magnetic resonance imaging showed a regrowth of the pituitary adenoma. A spontaneous remission of Cushing's disease without significant visual, neurologic or hormonal defects seems to be a much more common phenomenon than has been previously suggested. Cases with relapse after spontaneous remission of Cushing's disease are rare and the duration of remission in previous reports was within 5 years. We observed such a patient with a 7 year-remission caused by pituitary apoplexy. We consider that a careful long-term follow-up is required for patients with Cushing's disease whose remission was due to pituitary apoplexy.

Serum phenylalanine concentrations decreased in 4 patients with hyperphenylalaninemia after loading with tetrahydrobiopterin. There were no abnormalities in urinary pteridine excretion or in dihydropteridine reductase activity. However, mutations were detected in the phenylalanine hydroxylase gene, suggesting a novel subtype of phenylalanine hydroxylase deficiency that may respond to treatment with cofactor supplementation.

生後6ヵ月に発症したepilepsy with myoclonic absencesの6歳女児例を報告した。症例は乳児期より重度の精神運動発達の遅れを伴っていた。上肢のclonic movementに加え, 転倒を伴う発作も認めたため, 症候性全般てんかんと考え投薬を行ったが改善せず, 5歳4ヵ月時に入院精査を行った。発作型は基本的に2つあり, 1つは前兆なく突然意識消失し両眼球偏位と両上肢の律動性ミオクロニーがみられ, 発作終了後は速やかに意識回復をするミオクロニーを伴う欠神発作であった。他の1つは意識混濁が軽度で呼名に反応する発作で頻度は約10回に1回の割るでみられた。発作時ビデオ脳波筋電図同時記録では約3Hzの全般性同期性棘徐波群発を認め, 上肢のミオクロニーは発作波と対応していた。転倒を伴った発作の分析では背筋群の強直性収縮が原因と考えられた。sodiumvalproate, ethosuximideの投与により, 5歳10カ月から6ヵ月間, 発作はみられていない。

Some oral antibiotics contain a pivalate ester, because molecules with a pivalate entity show enhanced absorption in the intestine. Upon absorption, such a "prodrug" is broken down into the active form of a given antibiotic and a pivalate molecule, the latter of which is converted to pivaloylcarnitine through pivaloyl-CoA and is excreted in the urine. Long-term administration of drugs containing pivalate decreases blood carnitine level and causes defects in fatty acid oxidation. Here, we used liquid chromatography tandem mass spectrometry to measure carnitine and pivaloylcarnitine levels in two patients (Patient 1: 16-month-old boy and Patient 2: 18-month-old boy) with secondary carnitine deficiency and hypoglycemic convulsions caused by pivalate-containing antibiotics. Both patients were administered excessive doses of pivalate for the long-term treatment of recurrent infection, and consequently, the serum free carnitine levels were very low (Patient 1: 1.0 micromol/L and Patient 2: 0.4 micromol/L), compared to normal range of 33.3-43.0 micromol/l, while the serum pivaloylcarnitine levels were elevated from normally undetectable level (Patient 1: 3.7 micromol/L and Patient 2: 1.6 micromol/L). Patient 1 recovered immediately after the glucose infusion, whereas Patient 2 remained symptomatic even after blood glucose level was normalized and fully recovered after carnitine supplementation. The urine pivaloylcarnitine level in Patient 2 was increased during carnitine supplementation (from 821.4 to 12,200 micromol/g creatinine) even after discontinuing the antibiotics, indicating that a considerable amount of pivalate was accumulated in the tissues. In conclusion, long-term administration of pivalate-containing antibiotics should be avoided particularly in children.

Background: Valproate (VPA) is a simple fatty acid and a substrate for the fatty acid β-oxidation pathway. Previous data suggested that the toxicity of VPA may be provoked by carnitine deficiency and the inhibition of mitochondrial β-oxidation. Objective: The aim of the present study was to elucidate the effect of VPA treatment on carnitine and isomer-differentiated acylcarnitine disposition, and determined the relationships between acylcarnitines and blood VPA levels in long-term treated patients with VPA and/or other antiepileptic drugs. Methods: Serum samples were obtained from children aged 1–15 years old treated for at least 6 months with VPA alone (n = 28) or VPA combined with other anticonvulsants (n = 23) and untreated controls (n = 23). Serum acylcarnitines were separated from their isomers and quantified using high-performance liquid chromatography–tandem mass spectrometry. Results: We found higher 3-hydroxyisovalerylcarnitine levels and trace amounts of valproylcarnitine in both VPA monotherapy and polytherapy patients. Other acylcarnitines, hexanoylcarnitine, C12, C14:1-carnitines and the ratio of long-chain acylcarnitine to free carnitine were also higher in VPA polytherapy individuals than in controls. VPA monotherapy does not result in decreases in free carnitine or in the accumulation of long-chain acylcarnitines. Blood VPA concentrations correlated positively with hexanoylcarnitine, C12, C14:1, C16:1, C18:1-carnitines in all VPA-treated children (n = 51). Conclusion: Long-term VPA treatment in pediatric patients could affect some specific acylcarnitines, which is enhanced by the concomitant use of other anticonvulsants, and the formation of valproylcarnitine alone seems insufficient to develop severe carnitine deficiency at therapeutic doses of VPA.

A large quantity of propionylcarnitine in the urine of patients with propionic acidemia and methylmalonic aciduria was demonstrated. The amount excreted depended on the administered L-carnitine dose from 25 to 75 mg/kg/day. A high level of propionylcarnitine was also detected in the amniotic fluid of fetuses at risk of methylmalonic aciduria. Glutaric aciduria type 1 was characterized by excessive urinary excretion of glutarylcarnitine. In a neonate with glutaric aciduria type 2, several specific acylcarnitines were detected in the urine. These included isovaleryl-, acetyl-, isobutyryl-, and butyrylcarnitine as major carnitine esters and glutaryl-, and octanoylcarnitine as minor components. However, the pattern of acylcarnitines excreted changed from isovalerylcarnitine (via leucine) to isobutyrylcarnitine (via valine) during early life. In patients diagnosed as Reye syndrome, tissue carnitine deficiency was not always recognized and no decrease in the free/total carnitine ratio was found in the liver or muscle. The clinical and pathophysiological manifestations seen in these disorders are considered to relate to mitochondrial activity. Therefore, it is necessary to measure acylcarnitine fractions in the urine in order to obtain more precise information about mitochondrial function because carnitine and acylcarnitine compounds may express the metabolic state of mitochondria.

Due to its increased concentration in blood, 3-hydroxyisovalerylcarnitine (C5OH-I) is an important indicator for the diagnosis of organic acidemias in newborns. However, C5OH-I has not been used as a standard in tandem mass spectrometric (MS/MS) assays because its isolation is difficult. We developed a new synthesis of C5OH-I and investigated its behavior by MS/MS. A method using the multiple reaction monitoring (MRM) mode of MS/MS with HPLC was developed which provides high accuracy, precision and reproducibility. Acylcarnitine profiles in the serum and urine of a patient with multiple carboxylase deficiency (MCD) showed increased levels compared to a healthy patient.

An 18-month-old boy was treated with an antibiotic containing pivalic acid for 6 months for intractable otitis media and then developed repeated convulsions and loss of consciousness. Laboratory data showed hypoglycemia and hypocarnitinemia. Intravenous administration of glucose was ineffective against the seizures and loss of consciousness. However, the patient regained consciousness and recovered soon after intravenous infusion of carnitine. To our knowledge, intravenous carnitine administration that contributed to marked improvements in neurologic deficit caused by administration of an antibiotic containing pivalic acid has not been reported previously. These findings indicate that long-term use of such antibiotics should be avoided.

Background To evaluate the outcome of smell activity after endoscopic sinus surgery in chronic sinusitis, it is important to verify evidence of smoking-induced olfactory dysfunction. Methods In both the preoperative and the postoperative stages, the 5-odorant T&T olfactometer (T&T5) and the 40-item University of Pennsylvania Smell Identification Test (UPSIT40) were administered to 100 patients (84 men and 16 women; mean age, 49.5 years; range, 21–75 years) who underwent surgery for chronic sinusitis. Additionally, as more simplified measures, we adopted a 3-odorant T&T (T&T3) and a 12-item UPSIT (UPSIT12), and then compared findings with those of each original method. Results (1) Obvious correlations of scores were noticed both between T&T5 and T&T3 and between UPSIT40 and UPSIT12 (r = 0.964 and 0.893, respectively), (2) significant changes in postoperative scores were observed on all four measurements (p < 0.0001), (3) smoking-induced hyposmia was noticeable in older subjects but not in younger subjects, and (4) the correlations of postoperative scores and the age of smoker or the smoking dose was significant (UPSIT40, r = 0.825 or 0.642; UPSIT12, r = 0.666 or 0.428; T&T5, r = 0.447 or 0.476; T&T3, r = 0.457 or 0.500, respectively). Conclusion The abbreviated measures of T&T3 and UPSIT12 could be available enough to assess the effect of surgical intervention on olfaction, while the original UPSIT40 was considered to be the most sensitive among the four methods tested here for examining the impact of smoking on olfaction.

A novel therapeutic strategy for phenylketonuria (PKU) has been initiated in Japan. A total of 12 patients who met the criteria for tetrahydrobiopterin (BH(4))-responsive hyperphenylalaninemia (HPA) with a mutant phenylalanine hydroxylase (PAH) (EC 1.14.16.1) gene were recruited at 12 medical centers in Japan between June 1995 and July 2001. Therapeutic efficacy of BH(4) was evaluated in single-dose, four-dose, and 1-wk BH(4) loading tests followed by long-term BH(4) treatment, and also examined in relation to the PAH gene mutations. The endpoints were determined as the percentage decline in serum phenylalanine from initial values after single-dose (>20%), four-dose (>30%), and 1-wk BH(4) (>50%) loading tests. Patients with mild PKU exhibiting decreases in blood phenylalanine concentrations of >20% in the single-dose test also demonstrated decreases of >30% in the four-dose test. The 1-wk test elicited BH(4) responsiveness even in patients with poor responses in the shorter tests. Patients with mild HPA, many of whom carry the R241C allele, responded to BH(4) administration. No clear correlation was noted between the degree of decrease in serum phenylalanine concentrations in the single- or four-dose tests and specific PAH mutations. The 1-wk test (20 mg/kg of BH(4) per day) is the most sensitive test for the diagnosis of BH(4)-responsive PAH deficiency. Responsiveness apparently depends on mutations in the PAH gene causing mild PKU, such as R241C. BH(4) proved to be an effective therapy that may be able to replace or liberalize the phenylalanine-restricted diets for a considerable number of patients with mild PKU.

Patients with inborn errors of metabolism undergo liver transplantation, but the effect of transplanting the liver of healthy carriers of these conditions has not been fully clarified. A 6-year-old girl with classical citrullinemia, who repeatedly suffered from hyperammonemia, underwent living-related liver transplantation by using a segment of the liver of her mother, who was a heterozygote carrier for classical citrullinemia. Hyperammonemia alleviated in the patient after the transplantation, thereby dramatically improving her quality of life. Although the levels of plasma and urinary citrulline remained high postoperatively, there was no marked difference in the level of plasma citrulline up to 1 month after surgery when compared with that of previously reported orthotopic liver transplantation cases with classical citrullinemia.

We report the peculiar serial electroencephalographic (EEG) findings in a 7-year-old boy with glutaric aciduria type 1 during an episode of acute encephalopathy. The patient developed Reye-like syndrome triggered by cellulitis. Cranial magnetic resonance imaging demonstrated diffuse softening of cerebral hemisphere. The EEG on the day following onset of acute encephalopathy showed suppression burst pattern including continuous 14-15 Hz rhythmic waves at first. Then, periodic synchronous discharge appeared and lasted for about 40 minutes. Periodic synchronous discharge finally disappeared and nearly total electrocerebral silence continued. There have been no reports indicating such a change of EEG in a short period. The serial EEG changes probably reflect the process of electrical death of neurons in cerebral hemispheres.

To clarify the electroencephalographic characteristics of mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS), the medical records and electroencephalograms of six patients with MELAS and two of their relatives with MELA (mitochondrial myopathy, encephalopathy, and lactic acidosis, without strokelike episodes) were retrospectively reviewed. All have a point mutation in the mitochondrial DNA at nucleotide position 3243. The electroencephalograms (n = 79) were divided into four groups according to the time relation to the strokelike episode: (1) before the first strokelike episode, (2) within 5 days after the strokelike episode (acute stage), (3) between 6 days and 1 month after the strokelike episode (subacute stage), and (4) more than 1 month after the strokelike episode (chronic stage). In the acute stage, 10 of the 11 electroencephalograms (9 strokelike episodes in four patients) revealed focal high-voltage delta waves with polyspikes (FHDPS), which were recognized as ictal electroencephalogram. Ictal events during FHDPS included focal clonic or myoclonic seizure and migrainous headache. In the subacute and chronic stages, focal spikes or sharp waves and 14- and 6-Hz positive bursts were frequently recorded. The authors' results suggest that FHDPSs present a reliable and accurate indicator of a strokelike episode in patients with MELAS.

In isovaleric acidemia (IVA), accumulated isovaleryl-CoA in the mitochondrion induces variable metabolic disturbances. To remove intramitochondrial isovaleryl groups, glycine therapy has been advocated primarily. On the other hand, secondary carnitine deficiency has been documented in this disorder and carnitine supplementation alone has been reported to be effective. In the present study, we administered carnitine and glycine to patients with IVA, and investigated serum carnitine and urinary excretion of total and free carnitine, acylcarnitine profile (i.e., isovalerylcarnitine and acetylcarnitine), and isovalerylglycine. By adding carnitine to glycine supplementation, more isovalerylglycine, not only isovalerylcarnitine, was excreted in the urine. Acetylcarnitine was detected in the urine only when sufficient carnitine was supplemented. We concluded that combined therapy of glycine and carnitine is more effective and safer to eliminate isovaleryl-CoA in IVA than conventional therapy using either glycine or carnitine. Urinary acetylcarnitine concentration might be a good marker indicating the optimal dose of L-carnitine supplementation.

A 14-year-old girl, having mental and growth retardation with end stage renal disease, was affected by a stroke-like attack. The attack was associated with transient low density areas at both sides of the parietal portion on head CT. Lactic acidosis, hypertrophic cardiomyopathy, angina pectoris-like attacks, hypertension and hyperparathyroidism were also observed and they were supposedly due to mitochondrial cytopathy. No morphological or biochemical abnormalities were found on the mitochondrial respiratory chain. However, muscle carnitine palmitoyltransferase (CPT) activity was significantly low, which was restored to a normal level after hyperparathyroidism was controlled by alphacalcidol administration. Furthermore, we also found two more chronic renal failure patients with secondary hyperparathyroidism, as well as the primary hyperparathyroidism patient showing markedly low muscle CPT activity. These findings suggest the possible contribution of parathyroid hormone to lipid metabolism in skeletal muscle and to the myopathic manifestations often seen in hyperparathyroidism.

n-Acetylglycine, n-propionylglycine, n-butyrylglycine, isobutyrylglycine, n-valerylglycine, isovalerylglycine, heptanoylglycine, phenylacetylglycine and isovalerylglucuronide were identified based on their liquid chromatographic-atmospheric pressure chemical ionization mass spectra (LC-APCI-MS). We were able to detect the presence of urinary isovalerylglycine in two cases of isovaleric acidemia using LC-APCI-MS. Membrane-filtered urine samples were injected into the LC-APCI-MS system in the negative-ion mode without any further pretreatment, and large amounts of isovalerylglycine were detected as the [M-H]- ion. The urinary excretion of isovalerylglycine appeared to increase after L-carnitine therapy. This analytical method is quick and easy and it may be a useful tool in understanding dysfunctional conditions in isovaleric acidemia.

A 23-year-old Japanese man presented with status epilepticus unresponsive to medication, respiratory failure, rhabdomyolysis, myoglobinuria, and irreversible renal failure. Muscle biopsy revealed type 1 fiber atrophy and an increased type 2C fibers (7%). His carnitine palmitoyltransferase (CPT) I and II activities were 0.06 and 0.12 nmol/min/mg protein, as compared with a mean value of 0.22 ± 0.14 and 0.27 ± 0.07 nmol/min/mg protein, respectively, in control subjects. This appears to be the first report of this disorder presenting as status epilepticus. Metabolic encephalopathy due to CPT deficiency may have presented as status epilepticus. Seizures in the present case may have resulted from the functional disorder of brain due to CPT deficiency.

ITO, T., SUGIYAMA, N., KOBAYASHI, M., KIDOUCHI, K., ITOH, T., UEMURA, O., SUGIYAMA, K. and TOGARI, H. Alteration of Ammonia and Carnitine Levels in Short-Term Treatment with Pivalic Acid-Containing Prodrug. Tohoku J. Exp. Med., 1995, 175 (1), 43-53-We investigated the influence on mitochondrial functions in carnitine deficiency caused by short-term treatment of cefteram-pivoxil (CFTM-PI) which is one of pivaloyloxymethyl-esterified antibiotics in adult volunteers and diseased children. Administration of CFTM-PI caused hypocarnitinemia in all cases, and we observed a significant elevation of blood ammonia levels compared with those after its withdrawal in diseased children. A significant negative correlation was found between the levels of serum free carnitine and blood ammonia, and a positive correlation was observed between serum carnitine and blood glutamine levels in all adult samples and samples during administration in diseased children. Our data suggest that these antibiotic medications affect the mitochondrial function even in a short-term treatment and that L-carnitine supplementation would be necessary for patients treated with CFTM-PI.

The urinary acylcarnitine profiles of two mothers whose first children were diagnosed to have glutaric aciduria type 2 (multiple acyl-CoA dehydrogenation deficiency, electron transfer flavoprotein (ETF) deficiency) were analysed in the second pregnancy. Large volumes of tigrylcarnitine and isovalerylcarnitine and a little glutarylcarnitine were detected. Each fetus was also diagnosed to be abnormal by enzyme activity and immunoassay of ETF protein. The acylcarnitines in the mothers' urine disappeared in 1 week after labour or artificial abortion. Acylcarnitines were never detected in the urine of controls.

M. KOBAYASHI 1, H. MORISHITA 1, N. SUGIYAMA 1, K. YOKOCHI 1, M. NAKANO 1, Y. WADA 1, Y. HOTTA 2, A. TERAUCHI 3 and I. NONAKA 4 1Department of Paediatrics and ~First Department of Anatomy, Medical School, Nagoya City University, Kawasumi-cho, Mizuho-ku, Nagoya 467, Japan 3Higashimatsumoto National Sanatorium, Matsumoto 399-65, Nagano, Japan 4National Centre for Nervous, Mental and Muscular Disorders, Kodaira 187, Tokyo, Japan

A 23-week fetus who is thought to be affected with Fukuyama congenital muscular dystrophy (FCMD) is reported. Cortical dysplasia of the cerebrum was extensive and could be categorized into three major types. The cerebral cortex was thoroughly covered by glio-mesenchymal tissue (extracortical glial layer), in which neuronal clusters were irregularly scattered. Radial bundles of neuroglial tissue frequently extended from the cortex into the extra-cortical glial layer through the focally defective molecular layer and pia mater. The deep cerebral structures, such as basal ganglia, thalamus and white matter, appeared normal in contrast with extensive malformation in the cortex. Glial fibrillary acidic protein-immunoperoxidase stain revealed: (1) presence of abundant radial glial fibers in the ventricular, subventricular and intermediate zones; (2) focal or diffuse lack of glia limitans; (3) focal derangement of radial glial fibers; and (4) proliferation of stellate glial cells in the extra-cortical layer. It is suggested that ectopic accumulation of neurons into the extra-cortical glial layer seems a cardinal pathogenetic process to generate cortical dysplasia in FCMD. Early development of superficial glio-mesenchymal tissue seems essential for upward displacement of migrating neurons.

We report a case of NADH-CoQ reductase deficiency, which is the first case described in Japan. A 3-year-and-9-month-old-boy had a severe and progressive neurologic disorder characterized by psychomotor retardation, myoclonic epilepsy and spastic quadriplegia. Moreover he had a respiratory problem of uncertain etiology in the neonatal period. Venous blood lactate levels were strikingly increased, ranging from 16.8 to 47.4 mg/100 ml, with an abnormally high lactate-pyruvate ratio (21.2±1.7). Lactate and pyruvate levels in the cerebrospinal fluid (CSF) were also elevated (48.9 mg/100 ml and 2.09 mg/100 ml respectively). Histochemical investigation of a muscle specimen showed marked atrophy of type 1 and 2A fibers. No ragged red fiber was seen. Electron microscopy revealed a mild increase of lipid vacuoles among the myofibrils. The mitochondria showed no abnormal structure and no paracrystalline inclusion body. Biochemical studies of muscle mitochondria revealed a defective activity of NADH-CoQ reductase in the respiratory chain. We propose that cases with so-called mitochondrial myopathy should be classified according to the fundamental biochemical defects underlying of the clinical symptoms, and that the entity of NADH-CoQ reductase should be divided into two further subtypes, of which one is early onset type and the other late onset.

To investigate the molecular abnormality in the mitochondria from various tissues of an autopsied patient exhibiting mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes, we have examined the enzymatic activity, iron-sulfur cluster, and subunit composition of the NADH-ubiquinone oxidoreductase (complex I). Rotenone-sensitive NADH-cytochrome c reductase activity was found to be decreased in all the tissues examined. A detailed study of the liver mitochondria has shown that NADH-ubiquinone oxidoreductase activity was greatly diminished. Analysis of the electron paramagnetic resonance spectra of the liver submitochondrial particles revealed a disproportionate deficiency of iron-sulfur clusters in the complex I segment of the respiratory chain. Signals from the clusters N-2 and N-3 diminished more drastically than those from clusters N-1b and N-4. Immunoblotting analysis showed that the 75-kD, 51-kD, and several other subunits were markedly diminished among multiple subunit polypeptides of complex I. These findings suggest that the underlying bases for mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes are defects, at least, in the complex I subunits containing a flavin and/or iron-sulfur cluster(s), which resulted in deficiencies of some iron-sulfur clusters.

SAKUMA, T., ASAI, K., ICHIKI, T., SUGIYAMA, N., KIDOUCHI, K. and WADA, Y. Identification of Benzoylcarnitine in the Urine of a Patient of Hyperammonemia. Tohoku J. Exp. Med., 1989, 159 (2), 147-151-Benzoylcarnitine was identified in the urine of a patient with a carbamoyl-phosphate synthase I deficiency for whom sodium benzoate and L-carnitine had been used to treat hyperammonemia. This is a newly identified metabolite of benzoate. Its excretion in the urine was increased day by day at the administration of both sodium benzoate and L- carnitine from 0.10 to 2.25mmol/g creatinine. Since there is the possibility of a secondary carnitine deficiency and an increase of benzoyl toxicity after long-term therapy with benzoate supplementation and protein restriction, it is important to monitor the urinary excretion of benzoylcarnitine.

A technique for the identification of glutarylcarnitine in urine from a patient with glutaric aciduria type 1 is described. The patient's urine sample was partially purified using an anion exchange column and analyzed by a carboxylic acid analyzer fitted with an ODS reverse-phase column. The chromatogram of the patient's urine sample revealed 3 different peaks, which corresponded respectively to those of carnitine with amino acids, acetylcarnitine and glutarylcarnitine. Following hydrolysis of the sample, the chromatogram had no peaks of acetylcarnitine and glutarylcarnitine but had remarkably amplified peaks of carnitine, acetic acid and glutaric acid. The eluent fraction of glutarylcarnitine from the non-hydrolyzed sample was hydrolyzed and analyzed again. It no longer had the glutarylcarnitine peak on the chromatogram, but had only two separate peaks of carnitine and glutaric acid. This technique simplifies the identification of glutarylcarnitine, in that it requires only removal of organic acids for preparation of samples, and does not require radioisotope or mass spectrometry.

A quantitative analysis for urinary acylcarnitines in a patient with neonatal multiple acyl-CoA dehydrogenation deficiency is described. This method (liquid chromatography) can quantify twelve acylcarnitines including glutarylcarnitine and 3 isomeric acylcarnitines (butyryl-1, valeryl- and octanoylisomer) in urine. Before and up to the 15th hour of DL-carnitine therapy, isovalerylcarnitine was the largest single component existing in urinary acylcarnitines. Its excretion increased approximately 10 times within 1 day of DL-carnitine therapy. However, the acetyl-, the isobutyryl- and the butyrylcarnitine values increased gradually. From the 8th day of the therapy, the isobutyrylcarnitine value exceeded the isovalerylcarnitine. The patient's dominant urinary specific acylcarnitine derived from amino acids oxidation deficiency was changed from isovalerylcarnitine(leucine) to isobutyrylcarnitine(valine) during the early period of DL-carnitine therapy. Glutarylcarnitine was a minor component in the urine. Its degree of increase was as small as that of octanoylcarnitine. 2-Methylbutyrylcarnitine and propionylcarnitine were not detected.

Muscle biopsy specimens from two patients with MELAS syndrome (mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes) were studied biochemically. 14CO2 production rates from (1-14C)pyruvate, (U-14C)malate, and (1-14C)2-ketoglutarate were all decreased in intact mitochondria in both patients. Rotenone-sensitive NADH cytochrome c reductase activities were decreased to 8% (patient 1) and 6% (patient 2) of control values; succinate cytochrome c reductase and cytochrome c oxidase values were within normal limits. These results indicate that both patients have a defect of NADH-CoQ reductase of the respiratory chain and that MELAS can be brought about by a defect of NADH-CoQ reductase.