Cranial magnetic resonance imaging findings in children with nonsyndromic mitochondrial diseases

Cranial magnetic resonance imaging findings suggestive of specific mitochondrial syndromes are reported. However, cranial magnetic resonance imaging features in children with nonsyndromic mitochondrial diseases are rarely described. From January 1992-September 2009, data from 33 patients with nonsyndromic mitochondrial diseases were collected. We investigated cranial magnetic resonance imaging features in children with nonsyndromic mitochondrial diseases, and identified potential diagnostic characteristics. Eleven of 33 patients (33.3%) demonstrated normal findings, and 22 (66.7%) demonstrated abnormal findings. The most common abnormal finding was cerebral atrophy, with or without other lesion sites (15/33; 45.5%). The second most common was bilateral basal ganglia involvement (6/33; 18.2%). Follow-up imaging was performed in 20 patients. Ten of these 20 (50.0%) demonstrated evolutionary changes, in which progressive global brain atrophy was evident. Three patients with normal results and one patient with cerebral atrophy on initial imaging demonstrated prominent signal changes over the basal ganglia, brainstem, gray matter, white matter, and bilateral cerebellar hemispheres on follow-up imaging. Imaging in children with nonsyndromic mitochondrial diseases may produce variable findings. Normal results and cerebral atrophy on the initial cranial magnetic resonance imaging are commonly evident in this patient group.

Clinical manifestations in children with mitochondrial diseases

Mitochondrial diseases comprise a group of complex and heterogeneous genetic disorders. Variable clinical features present a major challenge in pediatric diagnoses. From January 1984-June 2009, 69 patients were diagnosed with either syndromic mitochondrial diseases or nonsyndromic mitochondrial diseases. Clinical manifestations, laboratory findings, and histopathologic results differentiating syndromic from nonsyndromic mitochondrial diseases were analyzed by chi(2) test, with cutoff significance at P = 0.05. The commonest clinical manifestation involved central nervous system signs (88.4%). A comparison of central nervous system signs in syndromic vs nonsyndromic mitochondrial diseases revealed significant differences in terms of headache, external ocular motility, and apnea (P < 0.05). A comparison of organ systems revealed a significant difference for signs of the cardiovascular system. Elevated initial blood lactate levels were evident in 40.6% of patients, and 84.8% produced abnormal results after oral glucose challenge. Ragged red fibers were observed in 51.6% of patients. The positive rate of mitochondrial gene mutation was 27.5%. Age and disease were directly related: the younger the age at initial disease onset, the higher the frequency of mortality and morbidity. Notorious variability in the presentation of mitochondrial diseases exists in all pediatric subspecialties. Greater familiarity with those signs will facilitate more accurate diagnoses.

Clinical features and therapeutic response in Taiwanese children with Wilson's disease: 12 years of experience in a single center

BACKGROUND

Wilson's disease (WD) is an autosomal recessive defect of cellular copper export. Early diagnosis in children is difficult due to its obscure clinical presentations. The efficacy of zinc salts is well documented, although there are limited data concerning zinc use in pediatric patients with WD.

METHODS

We performed a retrospective analysis of clinical features, laboratory results and treatment responses in children with WD diagnosed at Taichung Veterans General Hospital between 1996 and 2008. Diagnosis was established by low serum ceruloplasmin, high 24-hour urinary copper excretion, presence of Kayser-Fleischer rings, and mutation analysis.

RESULTS

Eleven children were included in this study. The main initial presentations were impaired liver function tests (6/11) and hemolytic anemia (2/11). Gene studies in seven children showed six different mutations (G934D, R778Q, C490X, 304insC, IVS4-1 G > C, P992I) and one possible novel mutation (L1181P). All patients had improved liver function tests and hemoglobin levels after treatment with D-penicillamine, trientine and zinc supplement therapy. During a mean period of 3.4 +/- 2.1 years with zinc therapy, six patients had serum zinc levels above the normal limit, and seven patients had serum copper levels below the normal range.

CONCLUSION

Serum ceruloplasmin and 24-hour urinary copper examinations could be used to rule out WD in children with chronic hepatitis and hemolytic anemia. Gene analysis is helpful for prompt diagnosis of asymptomatic siblings and patients with atypical features. Zinc treatment is generally safe in pediatric patients with WD. However, its adverse effects should be monitored.

Aromatic L-amino acid decarboxylase deficiency in Taiwan

BACKGROUND

Aromatic L-amino acid decarboxylase (AADC) deficiency is a rare autosomal recessive disorder of neurotransmitter synthesis. It has unique clinical presentations.

AIMS

The purpose of this study is to delineate the clinical features and molecular spectrum of AADC deficiency in Taiwanese infants and children.

METHODS

We report eight patients with characteristic clinical manifestations of AADC deficiency. Clinical presentations, treatment response, outcome and mutations of DOPA decarboxylase (DDC) gene were analyzed.

RESULTS

The clinical manifestations were similar to those previously reported, including symptoms onset before age 1 year with features of severe floppiness, oculogyric crises, athetoid movement, prominent startle response, tongue thrusting, ptosis, paroxysmal diaphoresis, nasal congestion, diarrhea, irritability and sleep disorders. In addition, we observed that all patients (100.0%) had small hands and feet. During the period of follow-up, all of them (100.0%) presented severe floppiness in spite of therapeutic trials with vitamin B6, dopamine agonist, MAO inhibitor and/or anticholinergics. Three different mutations were identified in the DDC gene, including two novel mutations 1303 C>T and 1367ins A and one IVS 6+4 A>T mutation. The IVS 6+4 A>T was a splicing mutation, which inserted an additional 37nt of intron 6 into the DDC mRNA. Thirteen out of 16 alleles (81.3%) carried IVS 6+4 A>T mutation and the IVS 6+4 A>T alleles shared a conserved haplotype.

CONCLUSIONS

Patients with AADC deficiency in Taiwan have particular clinical manifestations of small hands and feet, which have rarely been mentioned in the literature. The prevalence of IVS 6+4 A>T splicing mutation is high in our study group and the IVS 6+4 A>T mutation might have a founder effect.

Leigh syndrome: clinical and neuroimaging follow-up

Leigh syndrome, caused by dysfunction in mitochondrial energy metabolism, is an inherited, heterogeneous, and progressive neurodegenerative disorder of infancy and childhood. From 1983 to August 2006, 14 cases diagnosed with Leigh syndrome were studied in terms of characteristic neuroimaging findings and abnormal mitochondrial configurations under electron microscopy, as well as molecular analysis. Of the 14 cases, 11 presented clinical features before age 1 (79%). All 14 presented with variable symptoms of central nervous system involvement. The three most common symptoms were developmental delay (12/14; 86%), seizures (11/14; 79%), and altered consciousness (8/14; 57%). Extra-central nervous system manifestations were observed in 10 of the 14 cases, the most common symptoms being failure to thrive (5/14; 36%), pericardial effusion and dilated cardiomyopathy (3/14; 21%), and liver function impairment (3/14; 21%). In all 14 cases, neuroimaging revealed abnormal findings over the basal ganglion, brainstem, or both. The putamen was the most common lesion site in the basal ganglia (11/12; 92%). Cranial magnetic resonance imaging was used for follow-up in 6 cases because of changes in clinical features; in all 6 cases the imaging revealed evolution in the brain. Cranial magnetic resonance spectroscopy was performed in 3 cases and in 2 of them revealed lactate peaks during deterioration of the disease course. The prognosis for Leigh syndrome was poor during long-term follow-up. Seven cases were early fatalities, before 1 year and 6 months of age. Follow-up cranial magnetic resonance imaging together with magnetic resonance spectroscopy in cases with clinical evolution is helpful for monitoring this disease.

Do serological tests provide adequate rapid diagnosis of Mycoplasma pneumoniae infection?

This study was designed to evaluate the serologic response to Mycoplasma pneumoniae infection. A total of 589 children < or =18 years (190 in the year 2004; 399 in 2005) and 2,073 adults > or = 18 years of age (980 in the year 2004; 1,093 in 2005) with respiratory symptoms underwent serological testing for M. pneumoniae infection. The tests included passive particle agglutination (PA) and enzyme-linked immunosorbent assay (ELISA). The seroprevalence rates of M. pneumoniae infection in the years 2004 and 2005 were 6.9 and 10.1%, respectively. The seropositivity rate was significantly higher in children (29.6% in 2005; 23.7% in 2004) than in adults (2.9% in 2005; 3.7% in 2004) (odds ratio, 8.138 in 2004; 13.923 in 2005; 95% confidence interval, 5.077-13.045 in 2004; 9.220-21.026 in 2005). Paired sera for the PA test were obtained from 32 of 399 children, and 22 of them demonstrated at least fourfold rises in antibody titer. ELISA had a sensitivity of 77.3% and a specificity of 40.0%; PA had a sensitivity of 9.5% and a specificity of 80%. The ELISA test was superior to the PA test in diagnosing acute M. pneumoniae infection in children. Both tests were significantly more sensitive when they were performed 1 week after the onset of infection.

Data compression by the recursive algorithm of exponential bidirectional associative memory

A novel data compression algorithm utilizing the histogram and the high-capacity exponential bidirectional associative memory (eBAM) is presented. Since eBAM has been proved to possess high capacity and fault tolerance, it is suitable to be utilized in the data compression using the table-lookup scheme. The histogram approach is employed to extract the feature vectors in the given data. The result of the simulation of the proposed algorithm turns out to be better than the traditional methods.

Rapid diagnosis of Mycoplasma pneumoniae infection in children by polymerase chain reaction

BACKGROUND AND PURPOSE

Endemic atypical pneumonia was noted in central Taiwan during 2005. The serological response to Mycoplasma pneumoniae infection was usually poor in its early course; convalescent serum was needed in most cases, which was sometimes difficult to obtain in children. Empiric antimicrobial therapy was usually initiated before serological testing. A rapid test would be useful to define the etiology and initiate appropriate management. We studied the usefulness of polymerase chain reaction (PCR) analysis for diagnosis in this setting.

METHODS

This 1-year prospective study conducted during 2005 in central Taiwan enrolled 307 hospitalized children (aged 3 months to 16 years) with respiratory tract infections, some complicated with systemic manifestations, such as encephalitis and skin rash. Fifty one patients were excluded due to unavailability of data or lack of consent. PCR analysis of samples using a primer set for the P1 gene of M. pneumoniae was compared to serological testing, including particle agglutinin test and enzyme-linked immunosorbent assay.

RESULTS

263 throat swabs from 256 patients were available for PCR tests, and serological tests were performed in 140 children (55%) with clinical suspicion of atypical pneumonia. Eighty two children (32%) were positive by the PCR method and 76 (30%) were serologically positive. Seventy one patients (87%) with duration of disease onset of 2 to 7 days had positive PCR results. The mean age of patients with M. pneumoniae infection was 5.2 years, with 27% of patients <2 years old and 73% of patients >2 years of age. The diagnoses were as follows: pneumonia (n = 44); pneumonia complicated with pleural effusion (n = 12); bronchitis and bronchopneumonia (n = 18); asthmatic bronchitis (n = 2); croup syndrome (n = 1); pharyngitis (n = 3); and herpangina (n = 2). Coinfection with bacteria or virus was found in 21% of patients with M. pneumoniae infection.

CONCLUSIONS

The PCR method could provide earlier diagnosis of M. pneumoniae infection and was useful to identify variable clinical features of infection, especially in younger children.

The neurological evolution of Pearson syndrome: case report and literature review

BACKGROUND

Pearson syndrome (PS) is an uncommon specific syndrome among mitochondrial diseases. It has unique clinical presentations.

AIMS

The purpose of this article is to clarify the neurological evolution, neuroimage findings, molecular genetic analysis and outcomes in PS cases with neurologic manifestations.

METHODS

We described the clinical progress of a female patient who was diagnosed as PS with a novel 6.0 kbp mitochondrial DNA deletion. She had typical clinical features of PS in early infancy followed by multiple organs involvement after the age of 1 year. At age 3, Kearns-Sayre syndrome (KSS) and Leigh syndrome (LS) developed. We also reviewed PS cases reported in the literature and analyzed the neurological evolution.

RESULTS

Total 55 PS cases, including our index case, had been reported. Among them, 11 cases had detailed clinical descriptions in terms of hypotonia, developmental delay, ataxia or tremor. In whom, PS might evolve into KSS and/or LS: three cases evolving into KSS; one case on the transition of KSS; three cases evolve into LS; our index case has both presentations. The neuroimage findings of PS were quite different which might be from normal to specific abnormal findings over the cerebral white matter, cerebellum, basal ganglion and brainstem. Among those cases, the molecular analysis revealed large-scale mitochondrial deletion around 3.1-6.0kbp. The outcome of PS was opposite: either early death before age 4 or survived beyond age 7.

CONCLUSIONS

The neurological features of PS have potential evolution changes that are from normal, mild neurological deficits to special mitochondrial syndromes: KSS and LS. Closely monitoring neurological symptoms, arranging eye fundus examinations and neuroimaging studies in cases with changes of neurological signs are crucial.

Leukemoid reaction after methotrexate-induced pancytopenia in a patient undergoing continuous ambulatory peritoneal dialysis

Methotrexate has been used as an important alternative therapy in the treatment of various rheumatic diseases. Life threatening marrow suppression in end-stage renal disease patients undergoing hemodialysis or continuous ambulatory peritoneal dialysis has been reported. A 33-year-old woman with systemic lupus erythematosus undergoing chronic peritoneal dialysis developed severe mucositis and pancytopenia after low-dose methotrexate treatment for arthritis. The leukocyte count recovered after methotrexate was withdrawn but a leukemoid blood picture developed during her recovery. No evidence of leukemia was found on bone marrow biopsy. The leukocyte count gradually returned to normal with conservative therapy.

Activation of phosphoinositide 3-kinase and Src family kinase is required for respiratory burst in rat neutrophils stimulated with artocarpol A

Artocarpol A (ART), a natural product isolated from Artocarpus rigida, stimulated superoxide anion (O2*-) generation, which was inhibited by 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY 294002), a phosphoinositide 3-kinase (PI3K) inhibitor, in rat neutrophils. ART stimulated phosphorylation of protein kinase B (PKB/Akt) on both T308 and S473 residues, and LY 294002 inhibited these effects. Rat neutrophils expressed both class IA PI3K subunits (p85, p110alpha, p110beta, and p110delta) and a class IB PI3K subunit (p110gamma) as assessed by a combination of Western blotting and reverse transcription-polymerase chain reaction (RT-PCR) approaches. Stimulation of neutrophils with ART evoked phosphatidylinositol-3,4,5-trisphosphate (PtdIns(3,4,5)P3) formation, which reached a maximal level at 2 min and was attenuated by LY 294002, as evidenced by immunofluorescence microscopy and by flow cytometry. Detectable membrane-association of class IA PI3Ks, class IB PI3K and Ras was seen as early as 1.5, 0.5 and 1.5 min, respectively, after stimulation with ART. The kinetics of ART-induced Ras activation paralleled the kinetics of class IA PI3Ks recruitment to membrane caused by ART, and the p85 and p110gamma immunoprecipitates contain Ras. ART stimulated Src family kinase activation, which was detectable within 1.5 min of incubation with ART. Both Src kinase activity and PtdIns(3,4,5)P3 formation in ART-stimulated neutrophils were inhibited by 4-amino-1-tert-butyl-3-(1'-naphthyl)pyrazolo[3,4-d]pyrimidine (PP1 analog). PP1 analog also attenuated the ART-stimulated O2*- generation in rat neutrophils. These results indicate that the stimulation of respiratory burst by ART in neutrophils implicates PI3K signaling.

Corneal clouding: An infrequent ophthalmic manifestation of mitochondrial disease

Corneal clouding is uncommon in infants and children but when present in this age group, it is often associated with mucopolysaccharidoses or Fabry disease. This report describes the case of an 11-year-old male who demonstrated poor weight gain, short stature, segmental myoclonus, and learning problems from 5 years of age followed by general weakness and extremely poor balance. Corneal clouding was evident as a result of a blurred vision complaint at 9 years of age. Both urine metabolic screening for mucopolysaccharidoses and analysis of lysosomal enzymes displayed negative findings. Clinical conditions worsened, including ptosis, progressive weakness, and positive Gowers' sign. Oral glucose lactate stimulation test was positive, therefore a muscle biopsy was performed at 11 years of age. Light microscopy of muscle biopsy disclosed abundant ragged red fibers; electron microscopy revealed abnormal mitochondria in terms of tubular cristae, concentrated cristae, stacking cristae, and round granular patterns of inclusion bodies in the matrix. Thus mitochondrial disease was diagnosed. We conclude that mitochondrial disease should be added to the list of differential diagnosis of corneal clouding in children, especially in cases with normal urine metabolic screening for mucopolysaccharidoses or when assays of lysosomal enzymes appear normal.

Seventeen alpha-hydroxylase deficiency

Seventeen alpha-hydroxylase deficiency (17OHD) is a rare form of congenital adrenal hyperplasia in which defects in the biosynthesis of cortisol and sex steroid result in mineralocorticoid excess, hypokalemic hypertension and sexual abnormalities such as pseudohermaphroditism in males, and sexual infantilism in females. The disease is inherited in an autosomal recessive pattern, and is caused by mutations in the gene encoding cytochrome P450c17 (CYP17), which is the single polypeptide that mediates both 17alpha-hydroxylase and 17,20-lyase activities. We report the case of a 15-year-old patient with 17OHD who had a female phenotype but male karyotype (46,XY). The diagnosis was made based on classical clinical features, biochemical data and molecular genetic study. Two mutations were identified by polymerase chain reaction amplification and sequencing, including a S106P point mutation in exon 2 and a 9-bp (GACTCTTTC) deletion from nucleotide position 1519 in exon 8 of CYP17. The first of these mutations was found in the father and the second in the mother, and both have been previously reported in Asia. The patient's hypertension and hypokalemia resolved after glucocorticoid replacement and treatment with potassium-sparing diuretics. Sex hormone replacement was prescribed for induction of sexual development and reduction of the final height. Prophylactic gonadectomy was scheduled. In summary, 17OHD should be suspected in patients with hypokalemic hypertension and lack of secondary sexual development so that appropriate therapy can be implemented.

Capsaicin stimulates the non-store-operated Ca2+ entry but inhibits the store-operated Ca2+ entry in neutrophils

Rat neutrophils express the mRNA encoding for transient receptor potential (TRP) V1. However, capsaicin-stimulated [Ca2+]i elevation occurred only at high concentrations (> or = 100 microM). This response was substantially decreased in a Ca2+-free medium. Vanilloids displayed similar patterns of Ca2+ response with the rank order of potency as follows: scutigeral>resiniferatoxin>capsazepine>capsaicin=olvanil>isovelleral. Arachidonyl dopamine (AAD), an endogenous ligand for TRPV1, failed to desensitize the subsequent capsaicin challenge. Capsaicin-induced Ca2+ response was not affected by 8-bromo-cyclic ADP-ribose (8-Br-cADPR), the ryanodine receptor blocker, but was slightly attenuated by 1-[6-[17beta-3-methoxyestra-1,3,5(10)-trien-17-yl]amino]hexyl]-1H-pyrrole-2,5-dione (U-73122), the inhibitor of phospholipase C-coupled processes, 1-[beta-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl]-1H-imidazole (SKF-96365), the blocker of receptor-gated and store-operated Ca2+ (SOC) channels, 2-aminoethyldiphenyl borate (2-APB), the blocker of D-myo-inositol 1,4,5-trisphospahte (IP3) receptor and Ca2+ influx, and by ruthenium red, a blocker of TRPV channels, and enhanced by the Ca2+ channels blocker, cis-N-(2-phenylcyclopentyl)azacyclotridec-1-en-2-amine (MDL-12330A) and Na+-deprivation. In addition, capsaicin had no effect on the plasma membrane Ca2+-ATPase activity or the production of nitric oxide (NO) and reactive oxygen intermediates (ROI) or on the total thiols content. Capsaicin (> or = 100 microM) inhibited the cyclopiazonic acid (CPA)-induced store-operated Ca2+ entry (SOCE). In the absence of external Ca2+, the robust Ca2+ entry after subsequent addition of Ca2+ was decreased by capsaicin in CPA-activated cells. Capsaicin alone increased the actin cytoskeleton, and also increased the actin filament content in cell activation with CPA. These results indicate that capsaicin activates a TRPV1-independent non-SOCE pathway in neutrophils. The reorganization of the actin cytoskeleton is probably involved in the capsaicin inhibition of SOCE.

Distinct effects of N-ethylmaleimide on formyl peptide- and cyclopiazonic acid-induced Ca2+ signals through thiol modification in neutrophils

In this study, we demonstrate that N-ethylmaleimide (NEM), a cell permeable thiol-alkylating agent, enhanced the [Ca2+]i rise caused by stimulation with cyclopiazonic acid (CPA), a sarcoplasmic-endoplasmic reticulum Ca2+-ATPase inhibitor, in rat neutrophils. In addition, NEM attenuated the formyl-Met-Leu-Phe (fMLP)-induced [Ca2+]i rise whether NEM was added to cells prior to or after fMLP stimulation. Moreover, application of NEM after fMLP activation in the absence of external Ca2+ inhibited the Ca2+ signal upon addition of Ca2+ to the medium. Similar patterns were also obtained by using 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB), a cell impermeable dithiol-oxidizing agent, which replaced NEM in the CPA- and fMLP-induced [Ca2+]i rise experiments. Treatment with dithiothreitol (DTT), a cell permeable dithiol-reducing agent, N-acetyl-l-cysteine (NAC), a cell permeable monothiol-reducing agent, and tris-(2-carboxyethyl)phosphine (TCEP), a cell impermeable reductant without a thiol group, all rescued the fMLP-induced Ca2+ signal from NEM. Rat neutrophils express the mRNA encoding for transient receptor potential (TRP) C6, inositol trisphosphate receptor (IP3R) 2 and IP3R3. NEM had no effect on the mitochondrial membrane potential. NEM could restore the polarization and F-actin accumulation of fMLP-treated cells to those of the control. In the absence of external Ca2+, NEM rendered the CPA-induced [Ca2+]i elevation persistently but inhibited the fMLP-induced Ca2+ spike, which was reversed by tris-(2-cyanoethyl)phosphine (TCP), a cell permeable reductant without a thiol group. DTNB did not affect the Ca2+ spike caused by fMLP. These results indicate that through protein thiol oxidation, NEM affects the receptor-activated and the store depletion-derived Ca2+ signals in an opposing manner.

The blockade of cyclopiazonic acid-induced store-operated Ca2+ entry pathway by YC-1 in neutrophils

In the presence of external Ca2+, pretreatment of neutrophils with 3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole (YC-1) inhibited the cyclopiazonic acid (CPA)-induced [Ca2+](i) elevation in a concentration- but not a time-dependent manner, while YC-1 had no effect on the Ca2+ signals in a Ca2+-free medium. YC-1 failed to inhibit ATP- and interleukin-8 (IL-8)-induced [Ca2+](i) changes. Addition of YC-1 after cell activation strongly inhibited the CPA-induced [Ca2+](i) changes. In a classical Ca2+ readdition protocol, a similar extent inhibition of Ca2+ spike by YC-1 introduced either prior to or after CPA stimulation was obtained. In rat neutrophils, mRNA for endothelial differentiation gene (edg)1, edg5, edg6 and edg8, the putative targets for sphingosine 1-phosphate (S1P), could be detected. However, S1P was found to have little effect on Ca(2+) signals. YC-1 did not inhibit but enhanced the sphingosine-induced [Ca2+](i) changes. Inhibition by YC-1 of CPA-induced [Ca2+](i) changes was not prevented by 7-nitroindazole and N-(3-aminomethyl)benzylacetamidine (1400W), two nitric oxide synthase (NOS) inhibitors, by aristolochic acid, a phospholipase A(2) inhibitor, or by suspension in a Na(+)-deprived medium. YC-1 did not affect the mitochondrial membrane potential. Moreover, YC-1 did not alter [Ca2+](i) changes in response to ionomycin after CPA and formyl-Met-Leu-Phe (fMLP) stimulation in a Ca2+-free medium. YC-1 had no effect on the basal [Ca2+](i) level, the pharmacologically isolated plasma membrane Ca2+-ATPase activity, and Ba2+ entry into CPA-activated cells. YC-1 alone resulted in the accumulation of actin filaments in neutrophils, while significantly reduced the intensity of actin filament staining in the subsequent activation with CPA. These results indicate that YC-1 inhibited CPA-activated store-operated Ca2+ entry (SOCE) probably through the direct blockade of channel activation and/or the disruption of the integrity of the actin cytoskeleton necessary for supporting Ca2+ entry pathway in neutrophils.

Paralytic ileus in MELAS with phenotypic features of MNGIE

This report describes a child having the syndrome of overlapping phenotypic features of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) and mitochondrial neurogastrointestinal encephalopathy syndrome (MNGIE). Mitochondrial DNA analysis revealed a point mutation at position A3243G, whereas activity of thymidine phosphorylase and its corresponding gene analysis were normal. The most striking feature of this case was paralysis of one segment of the terminal ileum observed on laparotomy. The electron microscopic findings of the resected ileum and colon by limited right hemicolectomy disclosed accumulation of numerous enlarged mitochondria with ill-defined cristae which were similar to mitochondria reported in three previous MELAS cases and one MNGIE case with intestinal dysmotility. We emphasize that the MELAS and MNGIE phenotypes overlapped in this case and that the mechanism of acute ileus in MELAS was associated with functional paralysis of the intestine.

Maple syrup urine disease in the Austronesian aboriginal tribe Paiwan of Taiwan: a novel DBT (E2) gene 4.7 kb founder deletion caused by a nonhomologous recombination between LINE-1 and Alu and the carrier-frequency determination

Maple syrup urine disease (MSUD) is an autosomal recessive inborn error disorder derived from the accumulation of the branched-chain amino acids (BCAAs) leucine, isoleucine and valine. Either the E1alpha, E1beta or DBT (E2) genes are responsible for this neurometabolic disease. Here, we report the identification and characterization of a novel E2 gene 4.7 kb deletion as a rare nonhomologous recombination of the long interspersed nuclear elements 1 (LINE-1) in intron 10 and the Alu in the 3' UTR of the E2 gene from three classic MSUD patients of the Austronesian aboriginal tribe Paiwan in Taiwan. The E2 gene 4.7 kb deletion accounted for five out of six alleles in the three unrelated Paiwanese MSUD patients, indicating a founder effect. Carrier-frequency study revealed one deleted heterozygote out of 101 normal Paiwanese. As the nine Taiwanese Austronesian aboriginal tribes share a common origin, this E2 4.7 kb deletion may be preserved in some of the other Austronesian aboriginal tribes of Taiwan. This is the first comprehensive genetics study of MSUD in the Austronesian tribal groups as well as in Taiwan.

Wolfram syndrome: phenotype and novel mutation in two Taiwanese siblings

Wolfram syndrome (WS) is a rare autosomal recessive neurodegenerative disorder. The responsible gene, WFS1, was identified in 1998 and over 66 mutations have been reported since then. We report 2 siblings in a Taiwanese family with WS. They had similar clinical courses, including successive development of diabetes mellitus, optic atrophy, diabetes insipidus, hearing impairment, and urological complications from age 5 to 15 years. Rapid progression of systemic and neurological symptoms was noted in the elder brother. Mutation analysis of the 2 probands revealed compound heterozygotes of 1 novel and 1 previously reported mutation. Their parents and an asymptomatic sibling were carriers of 1 mutation.

A novel mutation in neonatal isolated sulphite oxidase deficiency

Isolated sulphite oxidase deficiency (ISOD) is a very rare hereditary metabolic disorder. Imaging findings of the neonatal form of ISOD, including multicystic leukoencephalopathy with brain atrophy, resemble those of severe ischemic changes of the brain. We report the case of a ten-month-old boy who exhibited neonatal seizures on the 24th day after birth. Excessive quantities of sulphite and S-sulphocysteine in the urine and normal blood uric acid were noted. These findings were consistent with those of ISOD. Point mutations were found in two alleles of the sulphite oxidase (SUOX) gene. One of the mutations was a 1029 C > G mutation, which resulted in an amino acid substitution of tyrosine to a stop code (Y343 X); and the other was a 479 G > A mutation, which resulted in an amino acid substitution of arginine to glutamine (R160 Q). Y343 X is a novel SUOX gene mutation. A review of the literature, including data from this report, showed that 3 of 6 cases had typical imaging findings characterized by initial cerebral edema followed by dramatic multicystic leukoencephalopathy. We emphasize that neonatal ISOD should be included in the differential diagnosis of neonates with unexplained hypoxic-ischemic changes on neuroimaging studies.

Novel mutation and prenatal sonographic findings of glutaric aciduria (type I) in two Taiwanese families

Glutaric aciduria type I (GA I) is an autosomal recessively inherited inborn error with a defect of the enzyme glutaryl-CoA dehydrogenase (GCDH), which has never been diagnosed prenatally in Taiwanese patients. We present the prenatal sonographic findings and mutational analysis data of three children in two Taiwanese families. One patient from each family was diagnosed postnatally due to macrocephaly and neurological deterioration at 4 months and 10 months, respectively. The third child, sister of the first patient, was diagnosed prenatally at 11 weeks' gestation through chorionic villus sampling (CVS). Molecular analysis revealed that the fetus and child in Family 1 were homozygous for a common mutation, IVS10 -2A>C, which has not been reported in the Caucasian population. The patient in Family 2 was a compound heterozygote for IVS10 -2A>C and a novel mutation 749T>C (L238P). After genetic counseling, the couple decided to continue the second pregnancy. However, dilatation of quadrigeminal cistern (QC) and suspicious macrocephaly were noted at 30 weeks. Progressive dilatation of the QC associated with macrocephaly, fronto-temporal atrophy and wide space of perisylvian fissure were found in the follow-up scans. The affected girl was delivered at 37 weeks' gestation by cesarean section. Postnatal magnetic resonance imaging (MRI) studies confirmed the prenatal sonographic findings. With prenatal sonographic findings and mutational analysis presented in the present cases, the feasibility of prenatal diagnosis of GA I in high-risk pregnancy can not be overlooked.

Left ventricular dysfunction in children with fulminant enterovirus 71 infection: an evaluation of the clinical course

We describe 2 children with typical hand, foot, and mouth disease due to enterovirus 71 infection, 1 of whom died. Both cases were complicated by acute fulminant shock syndrome; the patients had remarkable acute left ventricular dysfunction. The clinical experience indicates that the rapid death associated with fulminant enterovirus rhombencephalitis is the result of rapid cardiogenic shock rather than neurogenic pulmonary edema.