Perioperative management and outcomes for posterior spinal fusion in patients with Friedreich ataxia: A single-center, retrospective study.

BACKGROUND: Friedreich ataxia is a rare genetic disorder associated with progressive mitochondrial dysfunction leading to widespread sequelae including ataxia, muscle weakness, hypertrophic cardiomyopathy, diabetes mellitus, and neuromuscular scoliosis. Children with Friedreich ataxia are at high risk for periprocedural complications during posterior spinal fusion due to their comorbidities. AIM: To describe our single-center perioperative management of patients with Friedreich ataxia undergoing posterior spinal fusion. METHODS: Adolescent patients with Friedreich ataxia presenting for spinal deformity surgery between 2007 and 2023 were included in this retrospective case series performed at the Children's Hospital of Philadelphia. Perioperative outcomes were reviewed along with preoperative characteristics, intraoperative anesthetic management, and postoperative medical management. RESULTS: Seventeen patients were included in the final analysis. The mean age was 15 ± 2 years old and 47% were female. Preoperatively, 35% were wheelchair dependent, 100% had mild-to-moderate hypertrophic cardiomyopathy with preserved systolic function and no left ventricular outflow tract obstruction, 29% were on cardiac medications, and 29% were on pain medications. Intraoperatively, 53% had transesophageal echocardiography monitoring; 12% had changes in volume status on echo but no changes in function. Numerous combinations of total intravenous anesthetic agents were used, most commonly propofol, remifentanil, and ketamine. Baseline neuromonitoring signals were poor in four patients and one patient lost signals, resulting in 4 (24%) wake-up tests. The majority (75%) were extubated in the operating room. Postoperative complications were high (88%) and ranged from minor complications like nausea/vomiting (18%) to major complications like hypotension/tachycardia (29%) and need for extracorporeal membrane oxygenation support in one patient (6%). CONCLUSIONS: Patients with Friedreich ataxia are at high risk for perioperative complications when undergoing posterior spinal fusion and coordinated multidisciplinary care is required at each stage. Future research should focus on the utility of intraoperative echocardiography, optimal anesthetic agent selection, and targeted fluid management to reduce postoperative cardiac complications.

Diabetes mellitus y ataxia de Friedreich en un niño: una difícil coexistencia / Diabetes mellitus and Friedreich´s ataxia in a child: a complicated coexistence

La ataxia de Friedreich, de herencia autosómica recesiva causada por una expansión repetida de trinucleótidos se asocia, entre otras complicaciones sistémicas, con diabetes mellitus. La aparición de torpeza motriz, con dificultad en la carrera y el salto en un varón de 6 años motivaron el estudio genético para ataxia de Friedrich y permitieron confirmar el diagnóstico. Tres años más tarde, se diagnosticó diabetes mellitus y se inició el tratamiento con insulina. Durante el seguimiento, presentó un importante deterioro neurológico, con necesidad de usar silla de ruedas, lo que dificultó un adecuado control metabólico. Se presenta el manejo y la evolución de un paciente con ataxia de Friedreich y diabetes mellitus

Friedreich's ataxia is an autosomal recessive disease caused by trinucleotide repeat expansion, presenting among other systemic complications, diabetes mellitus. The appearance of motor clumsiness, with running and jumping difficulties in a 6-year-old boy prompted the genetic study of Friedreich's ataxia, confirming his diagnosis. After diagnosis,it was evaluated by Pediatric Cardiology, detecting the presence of non-obstructive hypertrophic cardiomyopathy, and by Pediatric Endocrinology, due to overweight. At 9 years of age, he was diagnosed with diabetes mellitus, a regimen of insulin treatment was initiated. During follow-up, he presented significant neurological deterioration, reaching the use of a wheelchair,which hinders adequate metabolic control. This is a report of a pediatric patient with Friedrich ataxia and diabetes mellitus.

Scoliosis in Friedreich's ataxia: longitudinal characterization in a large heterogeneous cohort.

OBJECTIVE: The objective of this study was to characterize the incidence and progression of scoliosis in the natural history of Friedreich's ataxia (FRDA) and document the factors leading to the requirement for corrective surgery. METHODS: Data on the prevalence of scoliosis and scoliosis surgery from up to 17 years of follow-up collected during a large natural history study in FRDA (1116 patients at 4928 visits) were summarized descriptively and subjected to time to event analyses. RESULTS: Well over 90% of early or typical FRDA patients (as determined by age of onset) developed intermediate to severe scoliosis, while patients with a later onset (>14 years) had no or much lower prevalence of scoliosis. Diagnosis of scoliosis occurs during the onset of ataxia and in rare cases even prior to that. Major progression follows throughout the growth phase and puberty, leading to the need for surgical intervention in more than 50% of individuals in the most severe subgroup. The youngest patients appear to delay surgery until the end of the growth period, leading to further progression before surgical intervention. Age of onset of FRDA before or after reaching 15 years sharply separated severe and relatively mild incidence and progression of scoliosis. INTERPRETATION: Scoliosis is an important comorbidity of FRDA. Our comprehensive documentation of scoliosis progression in this natural history study provides a baseline for comparison as novel treatments become available.

Defective palmitoylation of transferrin receptor triggers iron overload in Friedreich ataxia fibroblasts.

Friedreich ataxia (FRDA) is a frequent autosomal recessive disease caused by a GAA repeat expansion in the FXN gene encoding frataxin, a mitochondrial protein involved in iron-sulfur cluster (ISC) biogenesis. Resulting frataxin deficiency affects ISC-containing proteins and causes iron to accumulate in the brain and heart of FRDA patients. Here we report on abnormal cellular iron homeostasis in FRDA fibroblasts inducing a massive iron overload in cytosol and mitochondria. We observe membrane transferrin receptor 1 (TfR1) accumulation, increased TfR1 endocytosis, and delayed Tf recycling, ascribing this to impaired TfR1 palmitoylation. Frataxin deficiency is shown to reduce coenzyme A (CoA) availability for TfR1 palmitoylation. Finally, we demonstrate that artesunate, CoA, and dichloroacetate improve TfR1 palmitoylation and decrease iron overload, paving the road for evidence-based therapeutic strategies at the actionable level of TfR1 palmitoylation in FRDA.

Stress-Induced Mouse Model of the Cardiac Manifestations of Friedreich's Ataxia Corrected by AAV-mediated Gene Therapy.

Friedreich's ataxia (FA), an autosomal recessive disorder caused by a deficiency in the expression of frataxin (FXN), is characterized by progressive ataxia and hypertrophic cardiomyopathy. Although cardiac dysfunction is the most common cause of mortality in FA, the cardiac disease remains subclinical for most of the clinical course because the neurologic disease limits muscle oxygen demands. Previous FXN knockout mouse models exhibit fatal cardiomyopathy similar to human FA, but in contrast to the human condition, untreated mice become moribund by 2 months of age, unlike humans where the cardiac disease often does not manifest until the third decade. The study was designed to create a mouse model for early FA disease relevant to the time for which a gene therapy would likely be most effective. To generate a cardiac-specific mouse model of FA cardiomyopathy similar to the human disease, we used a cardiac promoter (αMyhc) driving CRE recombinase cardiac-specific excision of FXN exon 4 to generate a mild, cardiac-specific FA model that is normal at rest, but exhibits the cardiac phenotype with stress. The hearts of αMyhc mice had decreased levels of FXN and activity of the mitochondrial complex II/complex IV respiratory chain. At rest, αMyhc mice exhibited normal cardiac function as assessed by echocardiographic assessment of ejection fraction and fractional shortening, but when the heart was stressed chemically with dobutamine, αMyhc mice compared with littermate control mice had a 62% reduction in the stress ejection fraction (p < 2 × 10-4) and 71% reduction in stress-related fractional shortening (p < 10-5). When assessing functional cardiac performance using running on an inclined treadmill, αMyhc mice stayed above the midline threefold less than littermate controls (p < 0.02). A one-time intravenous administration of 1011 genome copies of AAVrh.10hFXN, an adeno-associated virus (AAV) serotype rh10 gene transfer vector expressing human FXN, corrected the stress-induced ejection fraction and fractional shortening phenotypes. Treated αMyhc mice exhibited exercise performance on a treadmill indistinguishable from littermate controls (p > 0.07). These αMyhc mice provide an ideal model to study long-term cardiac complications due to FA and AAV-mediated gene therapy correction of stress-induced cardiac phenotypes typical of human FA.

Treatment of dilated cardiomyopathy in a mouse model of Friedreich's ataxia using N-acetylcysteine and identification of alterations in microRNA expression that could be involved in its pathogenesis.

Deficient expression of the mitochondrial protein, frataxin, leads to a deadly cardiomyopathy. Our laboratory reported the master regulator of oxidative stress, nuclear factor erythroid 2-related factor-2 (Nrf2), demonstrates marked down-regulation after frataxin deletion in the heart. This was due, in part, to a pronounced increase in Keap1. To assess if this can be therapeutically targeted, cells were incubated with N-acetylcysteine (NAC), or buthionine sulfoximine (BSO), which increases or decreases glutathione (GSH), respectively, or the NRF2-inducer, sulforaphane (SFN). While SFN significantly (p < 0.05) induced NRF2, KEAP1 and BACH1, NAC attenuated SFN-induced NRF2, KEAP1 and BACH1. The down-regulation of KEAP1 by NAC was of interest, as Keap1 is markedly increased in the MCK conditional frataxin knockout (MCK KO) mouse model and this could lead to the decreased Nrf2 levels. Considering this, MCK KO mice were treated with i.p. NAC (500- or 1500-mg/kg, 5 days/week for 5-weeks) and demonstrated slightly less (p > 0.05) body weight loss versus the vehicle-treated KO. However, NAC did not rescue the cardiomyopathy. To additionally examine the dys-regulation of Nrf2 upon frataxin deletion, studies assessed the role of microRNA (miRNA) in this process. In MCK KO mice, miR-144 was up-regulated, which down-regulates Nrf2. Furthermore, miRNA screening in MCK KO mice demonstrated 23 miRNAs from 756 screened were significantly (p < 0.05) altered in KOs versus WT littermates. Of these, miR-21*, miR-34c*, and miR-200c, demonstrated marked alterations, with functional clustering analysis showing they regulate genes linked to cardiac hypertrophy, cardiomyopathy, and oxidative stress, respectively.

Proposta de aplicação da comunicação alternativa para paciente com doença neurodegenerativa e seu impacto na qualidade vida: relato de caso / Proposal of application of alternative communication for patient with neurodegenerative disease and its impact on quality of life: case report / Propuesta de aplicación de comunicación alternativa para paciente com enfermedad neurodegenerativa y su impacto en la calidad de vida: caso clínico

Trata-se de um relato de caso de um indivíduo do sexo masculino com 51 anos, nível superior completo, nível socioeconômico favorável, diagnosticado em 1999 com Ataxia de Friedreich. Chega ao ambulatório de Fonoaudiologia, com ênfase no atendimento de adultos com doenças degenerativas, sob encaminhamento da equipe de genética do serviço do mesmo hospital. Ao exame fonoaudiológico diagnostica-se uma disfagia orofaríngea de moderada a grave e uma disartria grave. A disfagia é reabilitada via home care particular por opção do paciente, e no ambulatório, com objetivo de melhora da qualidade de vida criou-se uma proposta de aplicação da comunicação aumentativa e/ou alternativa para o desenvolvimento das habilidades de comunicação do paciente que já não estava mais se expressando. Foram realizadas duas avaliações (pré e pós terapia) e quatro sessões de intervenção terapêutica para o aprendizado e implementação da prancha de comunicação alternativa. Ao término do processo terapêutico verificou-se baixa adesão ao uso da comunicação aumentativa e/ou alternativa, mesmo com a auto-percepção da ininteligibilidade da sua fala, utilizando a pasta restrita ao atendimento fonoaudiológico. Tanto o paciente quanto seus acompanhantes referiram que mesmo após várias tentativas houve negação ao uso da comunicação alternativa. Embora tenham sido poucas sessões, não houve impacto da qualidade de vida do paciente após uso da comunicação aumentativa e/ou alternativa.

Este es un informe del caso de un hombre de 51 años, con educación universitaria completa, estatus socioeconómico favorable, diagnosticado en 1999 con ataxia de Friedreich. Llega a la clínica de terapia del habla, con énfasis en ayudar a adultos con enfermedades degenerativas, bajo la guía del equipo de genética al servicio del mismo hospital. El examen notas la disfagia orofaríngea moderada a severa y la disartria severa. La disfagia se rehabilita mediante atención domiciliaria privada a elección del paciente y en la clínica ambulatoria con el objetivo de mejorar la calidad de vida, se creó una propuesta para la aplicación de comunicación aumentativa y/o alternativa para desarrollar las habilidades de comunicación del paciente que ya no era más expresándose a sí mismos. Se realizaron dos evaluaciones (pre y post terapia) y cuatro sesiones de intervención terapéutica para aprender e implementar el tablero de comunicación alternativo. Al final del proceso terapéutico, hubo una baja adherencia al uso de comunicación aumentativa y/o alternativa, incluso con la autopercepción de la ininteligibilidad de su discurso, usando la carpeta restringida a la terapia del habla. Tanto el paciente como sus compañeros informaron que incluso después de varios intentos hubo una negación del uso de comunicación alternativa. Aunque hubo pocas sesiones, no hubo impacto en la calidad de vida del paciente después de usar comunicación aumentativa y/o alternativa.

This is a case report of a 51-year-old male, with complete college education, favorable socioeconomic status, diagnosed in 1999 with Friedreich's Ataxia. He arrives at the speech therapy clinic, with an emphasis on assisting adults with degenerative diseases, under the guidance of the genetics team at the service of the same hospital. Speech examination examines moderate to severe oropharyngeal dysphagia and severe dysarthria. Dysphagia is rehabilitated via private home care at the patient's option and in the outpatient clinic with the objective of improving quality of life, a proposal for the application of augmentative and/or alternative communication was created to develop the communication skills of the patient who was no longer expressing himself. Two evaluations (pre and post therapy) and four therapeutic intervention sessions were carried out to learn and implement the alternative communication board. At the end of the therapeutic process, there was low adherence to the use of augmentative and / or alternative communication, even with the self-perception of the unintelligibility of his speech, using the folder restricted to speech therapy. Both the patient and his companions reported that even after several attempts there was a denial of the use of alternative communication. Although there were few sessions, there was no impact on the patient's quality of life after using augmentative and/or alternative communication.

Cardiomyopathy as the first manifestation of Friedreichs ataxia

We present the case of a female patient diagnosed in childhood with Friedreich Ataxia (FA). At the age of 6, she developed left congestive heart failure with cardiomyopathy, as evident on echocardiogram. Neurologic signs only appeared at age 7, including marked loss of muscle mass, gait instability, muscle clonus, and Babinski's signal. At age 27, she had a stroke and was hospitalized; a few days later, she had a cardiorespiratory arrest with asystole, leading to death. The autopsy disclosed severe cardiomyopathy and significant myocardial replacement with fibrosis; therefore, the cause of death was assumed to be heart failure. Compared to the literature, our case has some unique features, such as cardiac disease as the presenting manifestation instead of gait instability, which is the major initial sign in most FA cases. Since our patient was submitted to an autopsy, it was an opportunity to retrieve important data to confirm the diagnosis and to evaluate the pathophysiology of this entity, such as myocardium fibrosis and cerebellar degeneration. In summary, our case demonstrates that cardiac disease can be the first manifestation of FA, with eventual diagnostic and prognostic implications. In addition, the autopsy provided findings of severe cardiomyopathy associated with FA.

Scoliosis in Patients With Friedreich Ataxia: Results of a Consecutive Prospective Series.

STUDY DESIGN: Prospective monocentric study. OBJECTIVES: To describe the radiologic characteristics and evolution of spinal shapes in a pediatric cohort of patients with Friedreich ataxia (FA). SUMMARY OF BACKGROUND DATA: FA is a spinocerebellar degenerative disorder responsible for gait impairment in children and young adults, and several orthopedic deformities can occur during growth, including scoliosis. However, curves' characteristics and their natural evolution have been poorly described, and the subsequent therapeutic management remains controversial. METHODS: Sixty six FA patients were prospectively included between 2008 and 2017. Clinical, functional, and radiologic records were conducted twice a year. Coronal curve types, segmental measurements, and skeletal maturity were assessed. RESULTS: A scoliotic deformity was reported in 71% of the patients at a mean age of 11.7 ± 3.1 years. Average follow-up was 6 years, including 75% of patients with closed triradiate cartilage at latest examination. Mean Cobb angle was 34° ± 2°. Main right thoracic curves were the most frequent curves observed (36%), followed by double major (21%), thoracolumbar and left thoracic curves (13%), main lumbar (11%), and long C-shape curves (6%). Hyperkyphosis (>40°) was present in 66%, with an average kyphosis angle of 50° ± 3°, and anterior misalignment (>5°) occurred in 53%. The severity of the Cobb angle was neither correlated to the FA severity scores nor the age at FA diagnosis. An arthrodesis was performed in 9 patients, including 5 patients (45%) who were ambulatory at least 1 year after surgery. CONCLUSIONS: The prevalence of scoliosis in FA was high (71%), and thoracic hyperkyphosis, with anterior misalignment, was frequently observed, which might be related to the anterior imbalance frequently encountered in patients with an ataxia. Posterior fusion including sacral instrumentation was only performed in nonambulatory patients, and the loss of ambulation was not associated with spinal surgery. LEVEL OF EVIDENCE: Level IV.

Intrathecal Baclofen Therapy for Painful Muscle Spasms in a Patient with Friedreich's Ataxia.

Friedreich's ataxia (FA) is the most frequent hereditary ataxia syndrome, while painful muscle spasms and spasticity have been reported in 11-15% of FA patients. This report describes the successful management of painful spasms in a 65-year-old woman with FA via intrathecal baclofen (ITB) therapy following unsuccessful medical treatments. To our knowledge, this is the third reported case in the literature. Unfortunately, the pathophysiological characteristics of muscle spasms in FA are not well explored and understood while the therapeutic mechanisms of the different treatments are rather vague. Taking into consideration the suggested spinal atrophy in FA, the clinical resemblance of FA and chronic spinal injury muscle spasms, together with the rapid ITB therapy effectiveness in alleviating FA muscle spasms, we attempted to suggest a putative pathophysiological mechanism acting at the spinal level and possibly explained by the presence of independent spinal locomotor systems producing muscle spasms. Specifically, overexcitement of these centers, due to loss of normal regulation from upper CNS levels, may result in the uncontrolled firing of secondary motor neurons and may be the key to producing muscle spasms. However, further research under experimental and clinical settings seems to be necessary.

The importance of central auditory evaluation in Friedreich's ataxia / A importância da avaliação auditiva central na ataxia de Friedreich

ABSTRACT Objective To assess central auditory function in Friedreich's ataxia. Methods A cross-sectional, retrospective study was carried out. Thirty patients underwent the anamnesis, otorhinolaryngology examination, pure tone audiometry, acoustic immittance measures and brainstem auditory evoked potential (BAEP) assessments. Results The observed alterations were: 43.3% in the pure tone audiometry, bilateral in 36.7%; 56.6% in the BAEP test, bilateral in 50%; and 46.6% in the acoustic immittance test. There was a significant difference (p < 0.05) in the comparison between the tests performed. Conclusion In the audiological screening, there was a prevalence of the descending audiometric configuration at the frequency of 4kHz, and absence of the acoustic reflex at the same frequency. In the BAEP test, there was a prevalence of an increase of the latencies in waves I, III and V, and in the intervals of interpeaks I-III, I-V and III-V. In 13.3% of the patients, wave V was absent, and all waves were absent in 3.3% of patients.

RESUMO Objetivo Avaliar a função auditiva central na ataxia de Friedreich (AFRD). Métodos Foi realizado um estudo retrospectivo de corte transversal. 30 pacientes realizaram anamnese, avaliações otorrinolaringológica, audiológica, imitanciométrica e do potencial evocado auditivo de tronco encefálico (PEATE). Resultados As alterações observadas foram: 43,3% no exame audiométrico sendo 36,7% dos casos, bilateralmente; 56,6% na avaliação do PEATE com 50% dos casos, bilateralmente e 46,6% no exame imitanciométrico. Houve diferença significativa (p < 0,05) na comparação entre os exames realizados. Conclusão No exame audiológico, ocorreu uma preponderância maior da configuração audiométrica descendente a partir da freqüência de 4kHz e ausência do reflexo acústico na mesma frequência. No exame do PEATE, houve prevalência do aumento das latências nas ondas I, III e V, e nos intervalos dos interpicos I-III, I-V e III-V. Em 13,3% dos casos, a onda V estava ausente, e em 3,3% dos casos, todas as ondas estavam ausentes.

Deciphering the causes of sporadic late-onset cerebellar ataxias: a prospective study with implications for diagnostic work.

The management of sporadic late-onset cerebellar ataxias represents a very heterogeneous group of patients and remains a challenge for neurologist in clinical practice. We aimed at describing the different causes of sporadic late-onset cerebellar ataxias that were diagnosed following standardized, exhaustive investigations and the population characteristics according to the aetiologies as well as at evaluating the relevance of these investigations. All patients consecutively referred to our centre due to sporadic, progressive cerebellar ataxia occurring after 40 years of age were included in the prospective, observational study. 80 patients were included over a 2 year period. A diagnosis was established for 52 patients (65%) corresponding to 18 distinct causes, the most frequent being cerebellar variant of multiple system atrophy (n = 29). The second most frequent cause was inherited diseases (including spinocerebellar ataxias, late-onset Friedreich's disease, SLC20A2 mutations, FXTAS, MELAS, and other mitochondrial diseases) (n = 9), followed by immune-mediated or other acquired causes. The group of patient without diagnosis showed a slower worsening of ataxia (p < 0.05) than patients with multiple system atrophy. Patients with later age at onset experienced faster progression of ataxia (p = 0.001) and more frequently parkinsonism (p < 0.05) than patients with earlier onset. Brain MRI, DaT scan, genetic analysis and to some extent muscle biopsy, thoracic-abdominal-pelvic tomodensitometry, and cerebrospinal fluid analysis were the most relevant investigations to explore sporadic late-onset cerebellar ataxia. Sporadic late-onset cerebellar ataxias should be exhaustively investigated to identify the underlying causes that are numerous, including inherited causes, but dominated by multiple system atrophy.

Constrictive Pericarditis Versus Restrictive Cardiomyopathy?

About one-half of the patients with congestive heart failure have preserved left ventricular ejection fraction (HFpEF). Although the etiology of HFpEF is most commonly related to long-standing hypertension and atherosclerosis, a significant number of suspected HFpEF patients have a restrictive cardiomyopathy or chronic pericardial disease. Recognizing these syndromes is important because early diagnosis may lead to instituting specific therapy that may prolong survival, improve quality of life, and/or recognize and treat an underlying systemic disorder. Advances in diagnostic imaging, biomarkers, and genetic testing today allow identification of the specific etiology in most cases. Novel pharmacological, immunologic, and surgical therapies are leading to improved quality of life and survival.

Joint preserving surgery versus arthrodesis in operative treatment of patients with neuromuscular polyneuropathy: questionnaire assessment.

The purpose of the paper was to present the results of surgical treatment of foot deformities in peripheral neuropathies using bone procedures: both joint preserving and with joint arthrodesis. The study included 26 patients, 14 males and 12 females (43 feet). The age of the patients at surgery ranged from 5 to 55 years (average 23 years). The follow-up ranged from 0.5 to 15 years (average 4.3 years). Seventeen patients presented Charcot-Marie-Tooth disease, three Friedreich's ataxia and six peripheral motor and sensory neuropathies of undetermined nature. Sixteen patients had bilateral procedures. Four patients had to be re-operated during the follow-up. The patients were divided into four groups depending on the age and the surgical technique applied. The groups I and II (9 children, 17 feet) included patients with growth plate still present in the foot just before surgery. In the groups III and IV (17 adults, 26 feet), bone growth was completed. The assessment of all patients based on a modified AOFAS scale ranged from 44 to 105 points (mean 83.7; SD 17.5). The assessment on the subjective scale ranged from 3 to 10 points (mean 7.4; SD 2.1). The assessment of quality of life on the WOMAC scale ranged from 0 to 41 points (mean 15.7; SD 13.2). All patients stated that they would decide to undergo the treatment again. For groups I and II, joint preserving surgeries gave better results; however, the results could not be statistically confirmed. The results for the groups III and IV were inconclusive as to which surgical techniques should be preferred, arthrodesis or joint preserving. The results show that none of the surgical techniques used for correction of foot deformities in motor-sensory polyneuropathies seems to be preferable.

Acute colonic pseudo-obstruction after hysterectomy in a patient with Friedreich ataxia.

Acute colonic pseudo-obstruction is a rare complication of gynecological surgery. Despite the complete description of this condition, diagnosis remains difficult and is often delayed. Due to delay in diagnosis and existence of serious comorbid illnesses, morbidity and mortality approaches higher levels. Early recognition of signs and symptoms of this condition and prompt accurate management are vital to prevent serious mortality. Here, we report a case of acute colonic pseudo-obstruction after total abdominal hysterectomy in a patient with known Friedreich ataxia.

Modeling of Friedreich ataxia-related iron overloading cardiomyopathy using patient-specific-induced pluripotent stem cells.

Friedreich ataxia (FRDA), a recessive neurodegenerative disorder commonly associated with hypertrophic cardiomyopathy, is due to GAA repeat expansions within the first intron of the frataxin (FXN) gene encoding the mitochondrial protein involved in iron-sulfur cluster biosynthesis. The triplet codon repeats lead to heterochromatin-mediated gene silencing and loss of frataxin. Nevertheless, inadequacy of existing FRDA-cardiac cellular models limited cardiomyopathy studies. We tested the hypothesis that iron homeostasis deregulation accelerates reduction in energy synthesis dynamics which contributes to impaired cardiac calcium homeostasis and contractile force. Silencing of FXN expressions occurred both in somatic FRDA-skin fibroblasts and two of the induced pluripotent stem cells (iPSC) clones; a sign of stress condition was shown in FRDA-iPSC cardiomyocytes with disorganized mitochondrial network and mitochondrial DNA (mtDNA) depletion; hypertrophic cardiac stress responses were observed by an increase in α-actinin-positive cell sizes revealed by FACS analysis as well as elevation in brain natriuretic peptide (BNP) gene expression; the intracellular iron accumulated in FRDA cardiomyocytes might be due to attenuated negative feedback response of transferring receptor (TSFR) expression and positive feedback response of ferritin (FTH1); energy synthesis dynamics, in terms of ATP production rate, was impaired in FRDA-iPSC cardiomyocytes, which were prone to iron overload condition. Energetic insufficiency determined slower Ca(2+) transients by retarding calcium reuptake to sarcoplasmic reticulum (SR) and impaired the positive inotropic and chronotropic responses to adrenergic stimulation. Our data showed for the first time that FRDA-iPSCs cardiac derivatives represent promising models to study cardiac stress response due to impaired iron homeostasis condition and mitochondrial damages. The cardiomyopathy phenotype was accelerated in an iron-overloaded condition early in calcium homeostasis aspect.

Rare cardiomyopathies: diagnostic features.

Cardiomyopathies (CM) are an important and heterogeneous group of diseases affecting the myocardium. They can induce mechanical and/or electrical disorders and are due to a variety of causes, they frequently are genetic. However, since their high number and their clinical complexity, the identification is still a challenge. Echocardiography is a very useful tool in the assessment of CM. In this review we aim to define the typical clinical features and to discuss the main diagnostic tool, above all echocardiography that can help physicians in the correct assessment of CM.

Relation of cytosolic iron excess to cardiomyopathy of Friedreich's ataxia.

Cardiomyopathy is the leading cause of death in Friedreich's ataxia. This autosomal recessive disease is caused by a homozygous guanine-adenine-adenine trinucleotide repeat expansion in the frataxin gene (chromosome 9q21). One untoward effect of frataxin deficiency is the lack of iron (Fe)-sulfur clusters. Progressive remodeling of the heart in FA, however, may be more specifically related to sarcoplasmic Fe overload. The Fe-containing inclusions in a small percentage of cardiomyocytes may not represent purely mitochondrial accumulation of the metal. The objective of the present study was to re-examine the contribution of Fe to cardiomyocyte hypertrophy, fiber necrosis, and myocardial scarring, using a combination of X-ray fluorescence, slide histochemistry of Fe, and immunohistochemistry of 2 Fe-related proteins. Polyethylene glycol-embedded human cardiac tissues from the left and right ventricular walls, ventricular septum, right atrium, and atrial septum were studied using qualitative and quantitative X-ray fluorescence. Tissues were recovered from the polyethylene glycol matrix, re-embedded in paraffin, and sectioned for visualization of Fe, ferritin, and ferroportin. X-ray fluorescence showed quantifiable levels of Fe and zinc. Regions of significantly increased Fe (1 to 4 mm(2)) were irregularly distributed throughout the working myocardium. Fe granules were sparse in conductive tissue. Zinc signals remained unchanged. Robust cytosolic ferritin reaction product occurred in many fibers of the affected regions. Ferroportin displayed no response except in fibers with advanced Fe overload. These observations are at variance with the concept of selective Fe overload only in cardiac mitochondria. In conclusion, Fe-mediated damage to cardiomyocytes and myocardial scarring are more likely due to cytosolic Fe excess.

Clinical monitoring in a patient with Friedreich ataxia and osteogenic sarcoma.

Friedreich ataxia is an autosomal recessive neurodegenerative disorder caused by mutations in the FXN gene that result in abnormally low levels of the mitochondrial protein frataxin. The authors recently used a lateral flow immunoassay to measure frataxin levels in a large cohort of controls, carriers, and patients with the condition. The findings show that frataxin levels do not appreciably change over time and correlate well with GAA(1) repeat length and age of onset; thus, frataxin is a reliable and stable marker for severity of disease. In this article, the authors present a patient diagnosed as having Friedreich ataxia and osteosarcoma who received combined methotrexate, doxorubicin (Adriamycin), and cisplatin (MAP) chemotherapy over 8 months. The authors assessed the effect of treatment on frataxin levels, blood cell counts, and clinical markers of cardiomyopathy. Results of the regimen and the use of MAP chemotherapy for treatment of neoplasms in individuals with Friedreich ataxia are discussed.

Clinical data and characterization of the liver conditional mouse model exclude neoplasia as a non-neurological manifestation associated with Friedreich's ataxia.

Friedreich's ataxia (FRDA) is the most common hereditary ataxia in the caucasian population and is characterized by a mixed spinocerebellar and sensory ataxia, hypertrophic cardiomyopathy and increased incidence of diabetes. FRDA is caused by impaired expression of the FXN gene coding for the mitochondrial protein frataxin. During the past ten years, the development of mouse models of FRDA has allowed better understanding of the pathophysiology of the disease. Among the mouse models of FRDA, the liver conditional mouse model pointed to a tumor suppressor activity of frataxin leading to the hypothesis that individuals with FRDA might be predisposed to cancer. In the present work, we investigated the presence and the incidence of neoplasia in the largest FRDA patient cohorts from the USA, Australia and Europe. As no predisposition to cancer could be observed in both cohorts, we revisited the phenotype of the liver conditional mouse model. Our results show that frataxin-deficient livers developed early mitochondriopathy, iron-sulfur cluster deficits and intramitochondrial dense deposits, classical hallmarks observed in frataxin-deficient tissues and cells. With age, a minority of mice developed structures similar to the ones previously associated with tumor formation. However, these peripheral structures contained dying, frataxin-deficient hepatocytes, whereas the inner liver structure was composed of a pool of frataxin-positive cells, due to inefficient Cre-mediated recombination of the Fxn gene, that contributed to regeneration of a functional liver. Together, our data demonstrate that frataxin deficiency and tumorigenesis are not associated.