Life-threatening lactic acidosis occurring in adults with mitochondrial disorders.

Although relatively common in children, severe acute lactic acidosis is rare in adults with mitochondrial myopathies. We report here three cases, aged 27, 32 and 32 years, who developed life-threatening metabolic crisis with severe lactic acidosis, requiring hospitalisation in intensive care unit. Plasma lactates were elevated 10 to 15 fold normal values, necessitating extra-renal dialysis. By contrast CK levels were moderately increased (3 to 5N). No triggering factor was identified, but retrospectively all patients reported long-lasting mild muscle fatigability and weakness before their acute metabolic crisis. All of them recovered after prolonged intensive care but resting lactate levels remained elevated. Muscle biopsy showed ragged-red and COX-negative fibers in two patients and mild lipidosis in the third one. Heteroplasmic pathogenic point mutations were detected in MT-TL1 (m.3280G>A;m.3258C>T) and MT-TK (m.8363A>G). Life-threatening lactic acidosis may thus be a major inaugural clinical manifestation in adults with mitochondrial myopathies. Prolonged intensive care may lead to a dramatic and sustained improvement and is mandatory in such cases.

Myopathy with MTCYB mutation mimicking Multiple Acyl-CoA Dehydrogenase Deficiency.

We describe two patients with mitochondrial DNA mutations in the gene encoding cytochrome b (m.15579A>G, p.Tyr278Cys and m.15045G>A p.Arg100Gln), which presented as a pure myopathic form (exercise intolerance), with an onset in childhood. Diagnosis was delayed, because acylcarnitine profile showed an increase in medium and long-chain acylcarnitines, suggestive of multiple acyl-CoA dehydrogenase deficiency, riboflavin transporter deficiency or FAD metabolism disorder. Implication of cytochrome b in fatty acid oxidation, and physiopathology of the mutations are discussed.

Prediction of long-term prognosis by heteroplasmy levels of the m.3243A>G mutation in patients with the mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes syndrome.

BACKGROUND AND PURPOSE: Our aim was to determine the prognostic value of urine and blood heteroplasmy in patients with the m.3243A>G mutation. METHODS: Adults with the m.3243A>G mutation referred to our institution between January 2000 and May 2014 were retrospectively included. The relationship between their baseline clinical characteristics, their mutation load in urine and blood, and major adverse events (MAEs) during follow-up, defined as medical complications requiring a hospitalization or complicated by death, was studied. RESULTS: Of the 43 patients (age 45.6 ± 13.3 years) included in the study, 36 patients were symptomatic, including nine with evidence of focal brain involvement, and seven were asymptomatic. Over a 5.5 ± 4.0 year mean follow-up duration, 14 patients (33%) developed MAEs. Patients with MAEs had a higher mutation load than others in urine (60.1% ± 13.8% vs. 40.6% ± 26.2%, P = 0.01) and in blood (26.9% ± 18.4% vs. 16.0% ± 12.1%, P = 0.03). Optimal cutoff values for the prediction of MAEs were 45% for urine and 35% for blood. In multivariate analysis, mutation load in urine ≥45% [odds ratio 25.3; 95% confidence interval (CI) 1.1-567.8; P = 0.04], left ventricular hypertrophy (odds ratio 16.7; 95% CI 1.3- 222.5; P = 0.03) and seizures (odds ratio 48.3; 95% CI 2.5-933; P = 0.01) were associated with MAEs. CONCLUSIONS: Patients with the m.3243A>G mutation are at high risk of MAEs, which can be independently predicted by mutation load in urine ≥45%, a personal history of seizures, and left ventricular hypertrophy.

Adult cases of mitochondrial DNA depletion due to TK2 defect: an expanding spectrum.

OBJECTIVE: In this study we aim to demonstrate the occurrence of adult forms of TK2 mutations causing progressive mitochondrial myopathy with significant muscle mitochondrial DNA (mtDNA) depletion. METHODS: Patients' investigations included serum creatine kinase, blood lactate, electromyographic, echocardiographic, and functional respiratory analyses as well as TK2 gene sequencing and TK2 activity measurement. Mitochondrial activities and mtDNA were analyzed in the patients' muscle biopsy. RESULTS: The 3 adult patients with TK2 mutations presented with slowly progressive myopathy compatible with a fairly normal life during decades. Apart from its much slower progression, these patients' phenotype closely resembled that of pediatric cases including early onset, absence of CNS symptoms, generalized muscle weakness predominating on axial and proximal muscles but affecting facial, ocular, and respiratory muscles, typical mitochondrial myopathy with a mosaic pattern of COX-negative and ragged-red fibers, combined mtDNA-dependent respiratory complexes deficiency and mtDNA depletion. In accordance with the disease's relatively slow progression, the residual mtDNA content was higher than that observed in pediatric cases. That difference was not explained by the type of the TK2 mutations or by the residual TK2 activity. CONCLUSION: TK2 mutations can cause mitochondrial myopathy with a slow progression. Comparison of patients with similar mutations but different disease progression might address potential mechanisms of mtDNA maintenance modulation.

Type III dens invaginatus in a mandibular incisor: a case report of a conventional endodontic treatment.

This article presents one of the few reported cases of endodontic treatment of class III dens invaginatus involving mandibular incisor. Due to invagination extending through the root, supposedly communicating laterally with the periodontal ligament space through the pseudoforamen, this case was classified as Oehlers type IIIA. The periradicular radiolucency was evident around the root apex with 5.0 × 3.0 mm diameter. The conventional chemical and mechanical preparation with hand files and 2.5% sodium hypochlorite combined with intracanal dressing with calcium hydroxide for 6 weeks was able to promote the regression of lesion noted at 1-year follow-up. This case reinforces the precept that knowledge about the biologic aspects of endodontics combined with adherence to technical standards are able to resolve complex cases without the need of additional resources.

TWINKLE gene mutation: report of a French family with an autosomal dominant progressive external ophthalmoplegia and literature review.

BACKGROUND: Multiple mitochondrial DNA (mtDNA) deletions usually have a mendelian inheritance secondary to mutation in nuclear genes. One of these is the Twinkle gene whose mutation is responsible for autosomal dominant progressive external ophthalmoplegia (PEO). The number of reported cases with mainly myopathic symptoms and possible nervous system involvement related to Twinkle gene mutation is limited. We present a new French family of whom two members displayed myopathy and neuropathy associated with PEO, and we perform a clinical review in light of other observations reported in the literature. METHODS: The proband, one son and the daughter have been investigated. Southern blot analysis and long-range PCR assay have been performed from muscle biopsy specimens. Coding exons and flanking intron regions of polymerase gamma (POLG) and DNA helicase (Twinkle) genes were sequenced. RESULTS: Multiple mitochondrial DNA deletions have been found and sequencing of the Twinkle gene showed the change p.R374Q. CONCLUSION: Two other families from the literature also had the R374Q mutation. Symptoms reported in association with this mutation were myopathy, peripheral neuropathy, dysarthria and/or dysphagia, respiratory insufficiency and parkinsonism. Respiratory insufficiency caused by chest wall weakness was reported in other families with different Twinkle gene mutations, and one might provide exercise intolerance, dysarthria and/or dysphagia as symptoms in favor of the diagnosis. Occurrence of impressive emaciation was a peculiarity in our family.

A common pattern of brain MRI imaging in mitochondrial diseases with complex I deficiency.

OBJECTIVE: To identify a consistent pattern of brain MRI imaging in primary complex I deficiency. Complex I deficiency, a major cause of respiratory chain dysfunction, accounts for various clinical presentations, including Leigh syndrome. Human complex I comprises seven core subunits encoded by mitochondrial DNA (mtDNA) and 38 core subunits encoded by nuclear DNA (nDNA). Moreover, its assembly requires six known and many unknown assembly factors. To date, no correlation between genotypes and brain MRI phenotypes has been found in complex I deficiencies. DESIGN AND SUBJECTS: The brain MRIs of 30 patients carrying known mutation(s) in genes involved in complex I were retrospectively collected and compared with the brain MRIs of 11 patients carrying known mutations in genes involved in the pyruvate dehydrogenase (PDH) complex as well as 10 patients with MT-TL1 mutations. RESULTS: All complex I deficient patients showed bilateral brainstem lesions (30/30) and 77% (23/30) showed anomalies of the putamen. Supratentorial stroke-like lesions were only observed in complex I deficient patients carrying mtDNA mutations (8/19) and necrotising leucoencephalopathy in patients with nDNA mutations (4/5). Conversely, the isolated stroke-like images observed in patients with MT-TL1 mutations, or the corpus callosum malformations observed in PDH deficient patients, were never observed in complex I deficient patients. CONCLUSION: A common pattern of brain MRI imaging was identified with abnormal signal intensities in brainstem and subtentorial nuclei with lactate peak as a clue of complex I deficiency. Combining clinico-biochemical data with brain imaging may therefore help orient genetic studies in complex I deficiency.

Infecção urinária em gestantes: perfil de sensibilidade dos agentes etiológicos de gestantes atendidas pelo SUS na cidade de Palmas - PR / Urinary infection in pregnants: susceptibility profile of etiological agents in pregnants followed by SUS in the city of Palmas - PR

Objetivo: determinar o perfil de sensibilidade dos agentes etiol6gicos de infecl,(8o do trato urinario (ITU) em gestantes atendidas pelo SUS, na cidade de Palmas- PR, para trat;;:ar perfil epidemiol6gico e diretrizes terapeuticas.Metodos: Foram avaliadas amostras urinarias de 203 gestantes no periodo de setembro de 2007 a janeiro de 2008. Nas culturas positivas, foi realizada a identifical,(8o e o antibiograma. Este ultimo foi realizado por disco- difusao (Kirby e Bauer) seguindo as diretrizes do CLSI2007. Resultados: Das amostras analisadas, 17 (8,4%) foram positivas. Os agentes isolados foram a Escherichia coli (82,3%); Streptococcus agalactiae (11,7%) e Staphylococcus saprophyticus (5,9%). Dos antibi6ticos testados e que podem ser administrados durante a gestal,(8o, as cefalosporinas, a fosfomicina e a nitrofurantoina foram os que apresentaram melhor eficacia frente aos uropat6genos isolados.Conclusao: Os resultados obtidos estao alinhados com a literatura consultada e servem de base para a determinat;;:ao de terapia empirica destas pacientes, quando for necessaria.

Objective: to determine the susceptibility profile of etiological agents of UTI in pregnant women by followedPublic Healt System in the city of Palmas- PR, to draw epideological profile and treatment guidelines. Methods: 203 urinary samples of pregnant women were evaluated between September 2007 and January 2008. Positive urinary cultures were submitted to bacterial identification and antibiotic susceptibility testing. The latter was performed by disky- diffusion method (Kirby and Bauer), following the guidelines of the CLSI2007. Results: Of the samples analyzed, 17 (8,4%) were positive. The agents isolated were Escherichia coli (82,3%), Streptococcus agalactiae (11,7%) and Staphylococcus saprophyticus (5,9%). The antibiotics that were tested and wich can be administred during pregnancy, the cephalosporins, fosfomycin and nitrofurantoin were effective against the uropatogens isolated. Conclusion: The results are a/ignes with literature data and can be used as the basis for standardizing the empirical treatment when it is necessary.

Cardiac involvement is frequent in patients with the m.8344A>G mutation of mitochondrial DNA.

BACKGROUND: Cardiac complications, such as myocardial disease and arrhythmias, are frequent and may be severe in patients with mitochondrial disease. We sought to determine the prevalence and the prognostic value of cardiac abnormalities in a series of patients carrying the m.8344 A>G mutation. METHODS: We retrospectively collected data concerning a cohort of patients carrying the m.8344A>G mutation. Patients systematically underwent neurologic examination, muscular biopsy, measurement of forced vital capacity, and cardiac evaluation including electrocardiogram, echocardiography, and 24-hour ambulatory electrocardiogram at diagnosis. Neurologic and cardiac evaluations were repeated during follow-up at least every 2 years. RESULTS: Eighteen patients (mean age 39.3 +/- 17.3 years, 10 women) from 8 families were investigated. Mean follow-up duration was 5.0 +/- 2.7 years. Cardiac abnormalities were identified at diagnosis in 8 patients (44.4%, age 39.1 +/- 17.7 years), including dilated cardiomyopathy in 4, Wolff-Parkinson-White syndrome in 3, incomplete left bundle branch block in 1, and ventricular premature beats in 1. Two additional patients developed left ventricular dysfunction during follow-up and 2 patients died due to heart failure. Subgroup analyses identified early age at disease onset as the only factor significantly associated with myocardial dysfunction. CONCLUSIONS: We identified a high prevalence of ventricular dysfunction and Wolff-Parkinson-White syndrome. Myocardial involvement was associated with an increased risk of cardiac death due to heart failure, suggesting that cardiac investigations should be systematically considered in patients carrying the m.8344A>G mutation.

Severe epilepsy as the major symptom of new mutations in the mitochondrial tRNA(Phe) gene.

OBJECTIVE: To present 2 families with maternally inherited severe epilepsy as the main symptom of mitochondrial disease due to point mutations at position 616 in the mitochondrial tRNA(Phe) (MT-TF) gene. METHODS: Histologic stainings were performed on skeletal muscle slices from the 2 index patients. Oxidative phosphorylation activity was measured by oxygraphic and spectrophotometric methods. The patients' complete mitochondrial DNA (mtDNA) and the relevant mtDNA region in maternal relatives were sequenced. RESULTS: Muscle histology showed only decreased overall COX staining, while a combined respiratory chain defect, most severely affecting complex IV, was noted in both patients' skeletal muscle. Sequencing of the mtDNA revealed in both patients a mutation at position 616 in the MT-TF gene (T>C or T>G). These mutations disrupt a base pair in the anticodon stem at a highly conserved position. They were apparently homoplasmic in both patients, and had different heteroplasmy levels in the investigated maternal relatives. CONCLUSIONS: Deleterious mutations in the mitochondrial tRNA(Phe) may solely manifest with epilepsy when segregating to homoplasmy. They may be overlooked in the absence of lactate accumulation and typical mosaic mitochondrial defects in muscle.

[Multiple acyl-CoA dehydrogenase deficiency (MADD): a curable cause of genetic muscular lipidosis]. / Déficit multiple en acyl-CoA déshydrogénases : une cause traitable de lipidose musculaire d'origine génétique.

INTRODUCTION: Multiple acyl-CoA dehydrogenase deficiency (MADD) is a rare genetic disease involving fatty acid oxidation. It is due to the deficiency of one of the two electron transporters: electron transfer flavoprotein (ETF) or electron transfer flavoprotein ubiquinone oxydoreductase (ETF-QO). Symptoms begin more often in childhood or in young adulthood with a multisystemic disease with encephalopathy or muscular weakness. CASE REPORTS: We report here two adult cases with ETF-QO deficiency, confirmed by mutation analysis (ETFDH gene), revealed by a muscular weakness associated with muscle lipidosis. One of our patients presented an acute encephalopathy with vomiting ten years before the onset of muscular symptoms. The second patient exhibited a slowly progressive pelvic girdle muscle weakness. Diagnosis was established by characteristic abnormalities of acylcarnitine profile by tandem mass spectrometry. For both patients, a dramatic clinical improvement was observed under treatment with riboflavine and L-carnitine. CONCLUSION: Since it is a treatable disorder, this diagnosis must be considered by performing an acylcarnitine profile in all patients presenting with an unexplained muscular weakness.

Collated mutations in mitochondrial DNA (mtDNA) depletion syndrome (excluding the mitochondrial gamma polymerase, POLG1).

These tables list both published and a number of unpublished mutations in genes associated with early onset defects in mitochondrial DNA (mtDNA) maintenance including C10orf2, SUCLG1, SUCLA2, TYMP, RRM2B, MPV17, DGUOK and TK2. The list should not be taken as evidence that any particular mutation is pathogenic. We have included genes known to cause mtDNA depletion, excluding POLG1, because of the existing database (http://tools.niehs.nih.gov/polg/). We have also excluded mutations in C10orf2 associated with dominant adult onset disorders.

Development and implementation of standardized respiratory chain spectrophotometric assays for clinical diagnosis.

Diversity of respiratory chain spectrophotometric assays may lead to difficult comparison of results between centers. The French network of mitochondrial diseases diagnostic centers undertook comparison of the results obtained with different protocols in the French diagnostic centers. The diversity of protocols was shown to have striking consequences, which prompted the network to undertake standardization and optimization of the protocols with respect to clinical diagnosis, i.e. high velocity while maintaining linear kinetics relative to time and enzyme concentration. Assays were set up on animal tissues and verified on control human muscle and fibroblasts. Influence of homogenization buffer and narrow range of optimal concentration of phosphate, substrate and tissue were shown. Experimental data and proposed protocols have been posted on a free access website. Their subsequent use in several diagnostic centers has improved consistency for all assays.

[Clinical variability and diagnosis steps in childhood mitochondrial disease]. / Variabilité clinique et conduite diagnostique des cytopathies mitochondriales : à propos d'une série de 18 cas pédiatriques.

OBJECTIVES: Mitochondrial respiratory chain deficiencies are known for their high clinical variability. Difficult to diagnose, the prevalence of these diseases is probably underestimated. METHODS: We report 18 children diagnosed with respiratory chain deficiency at the Tours University Hospital over the past 10 years. RESULTS: Three clinical profiles can be distinguished depending on the age at onset of the first symptoms: the neonatal period (4 cases), between 1 month and 2 years of age (10 cases), and after 10 years (4 cases). However, no clinical feature appears specific of any age group. In contrast, respiratory chain analysis on liver biopsy was very informative for all our patients at any age and with any clinical presentation, even with predominant neurological symptoms. CONCLUSIONS: These biochemical analyses support the diagnosis of mitochondrial disorders in view of molecular analysis, which nevertheless frequently remains inconclusive. These investigations should benefit from the new molecular screening technologies based on DNA chips that can identify the genomic mutations responsible for these severe and relatively frequent diseases.

Syzygium jambolanum treatment improves survival in lethal sepsis induced in mice.

BACKGROUND: The leaves and the fruits from Syzygium jambolanum DC.(Myrtaceae), a plant known in Brazil as sweet olive or 'jambolão', have been used by native people to treat infectious diseases, diabetes, and stomachache. Since the bactericidal activity of S. jambolanum has been confirmed in vitro, the aim of this work was to evaluate the effect of the prophylactic treatment with S. jambolanum on the in vivo polymicrobial infection induced by cecal ligation and puncture (CLP) in mice. METHODS: C57Bl/6 mice were treated by the subcutaneous route with a hydroalcoholic extract from fresh leaves of S. jambolanum (HCE). After 6 h, a bacterial infection was induced in the peritoneum using the lethal CLP model. The mice were killed 12 h after the CLP induction to evaluate the cellular influx and local and systemic inflammatory mediators' production. Some animals were maintained alive to evaluate the survival rate. RESULTS: The prophylactic HCE treatment increased the mice survival, the neutrophil migration to infectious site, the spreading ability and the hydrogen peroxide release, but decreased the serum TNF and nitrite. Despite the increased migration and activation of peritoneal cells the HCE treatment did not decrease the number of CFU. The HCE treatment induced a significant decrease on the bone marrow cells number but did not alter the cell number of the spleen and lymph node. CONCLUSION: We conclude that the treatment with S. jambolanum has a potent prophylactic anti-septic effect that is not associated to a direct microbicidal effect but it is associated to a recruitment of activated neutrophils to the infectious site and to a diminished systemic inflammatory response.

Anderson's disease (chylomicron retention disease): a new mutation in the SARA2 gene associated with muscular and cardiac abnormalities.

Anderson's disease (AD) or chylomicron retention disease (CMRD) is a rare hereditary lipid malabsorption syndrome linked to SARA2 gene mutations. We report in this study a novel mutation in two sisters for which the Sar1b protein is predicted to be truncated by 32 amino acids at its carboxyl-terminus. Because the SARA2 gene is also expressed in the muscle, heart, liver and placenta, extraintestinal clinical manifestations may exist. For the first time, we describe in this study in the two sisters muscular as well as cardiac abnormalities that could be related to the reported expression of SARA2 in these tissues. We also evaluated six other patients for potential manifestations of the SARA2 mutation. The creatine phosphokinase levels were increased in all patients [1.5-9.4 x normal (N)] and transaminases were moderately elevated in five of the eight patients (1.2-2.6 x N), probably related to muscle disease rather than to liver dysfunction. A decreased ejection fraction occurred in one patient (40%, N: 60%). The muscle, liver and placental tissues that were examined had no specific abnormalities and, in particular, no lipid accumulation. These results suggest that myolysis and other extraintestinal abnormalities can occur in AD/CMRD and that the clinical evaluation of patients should reflect this.

Muscle coenzyme Q10 deficiencies in ataxia with oculomotor apraxia 1.

APTX gene mutations responsible for ataxia-oculomotor apraxia 1 (AOA1) were identified in a family previously reported with ataxia and coenzyme Q10 (CoQ10) deficiency. We measured muscle CoQ10 levels in six patients with AOA1 and found decreased levels in five. Patients homozygous for the W279X mutation had lower values (p = 0.003). A therapeutic trial of CoQ10 may be warranted in patients with AOA1.

Anti-thrombotic effect of chronic oral treatment with Orbignya phalerata Mart.

Babassu is the popular name of Orbignya phalerata Mart. (Arecaceae). The mesocarp flour obtained from their fruits has been used in Brazil as medicine in the treatment of pains, constipation, obesity, leukemia, rheumatism, ulcerations, tumors, inflammations and venous diseases. The effect of the chronic oral treatment with aqueous extract of babassu mesocarp (500mg/kgday) on the number of platelets, the prothrombin time (PT), the activated partial thromboplastin time (aPTT), the nitric oxide (NO) production and the carrageenin-induced thrombosis was evaluated, using C57Bl/6 mice. The chronic oral treatment with babassu mesocarp induced an anti-thrombotic effect. There was a 88.9% reduction in the necrosis of the tail. This effect seems to be related to an increase in the ability of the macrophage to produce NO and to a slow coagulation process associated to an increase of 12.0 and 13.9% in PT and aPTT, respectively. However, the anti-thrombotic effect seems to be not related to alterations in the number of platelets. It is possible to conclude that the oral treatment with babassu mesocarp has a significant anti-thrombotic effect, which could justify the popular use of babassu mesocarp in the treatment of venous diseases. Meanwhile, this study suggests a potential use of babassu mesocarp as a prophylactic agent to avoid thrombosis events.

Kearns Sayre syndrome: an unusual form of mitochondrial diabetes.

Kearns Sayre syndrome (KSS) is a mitochondrial disorder characterized by the emergence before age 20 of progressive external ophthalmoplegia, pigmentary retinopathy, together with other heterogeneous clinical manifestations, including cardiac conduction defects, muscle abnormalities and endocrinopathies. KSS is associated with large heteroplasmic deletions in mitochondrial DNA. We report the case of a 43-year-old woman, with diabetes mellitus as a first manifestation at age 19. Later, she exhibited bilateral ptosis and external ophthalmoplegia with progressive worsening. DNA analysis identified a large mitochondrial DNA (mtDNA) deletion, which confirmed the diagnosis of KSS. By reporting this case with diabetes mellitus as first manifestation, we aim at emphasizing problems of diagnosis in these subtypes of mitochondrial diabetes.