Could mitochondrial haplogroups play a role in sporadic amyotrophic lateral sclerosis?

Mitochondrial impairment has been implicated in the pathogenesis of the amyotrophic lateral sclerosis (ALS). Furthermore, mitochondrial-specific polymorphisms were previously related to other neurodegenerative diseases, such as Parkinson, Friedreich and Alzheimer disease. To investigate if specific genetic polymorphisms within the mitochondrial genome (mtDNA) could act as susceptibility factors and contribute to the clinical expression of sporadic ALS (sALS), we have genotyped predefined European mtDNA haplogroups in 222 Italian patients with sALS and 151 matched controls. Individuals classified as haplogroup I demonstrated a significant decrease in risk of ALS versus individuals carrying the most common haplogroup, H (odds ratio 0.08, 95% confidence interval 0.04-0.4, p < 0.01). Further stratification of the dataset by sex, age and site of onset of disease and survival failed to reach significance for association. Our study provides evidence of the contribution of mitochondrial variation to the risk of ALS development in Caucasians. Further it may help elucidate the mechanism of the mitochondrial dysfunction detectable in ALS, and may be of relevance in development of strategies for the treatment of this disease.     

Adult-onset mitochondrial movement disorders: a national picture from the Italian Network

Journal of Neurology - Both prevalence and clinical features of the various movement disorders in adults with primary mitochondrial diseases are unknown. Based on the database of the...     

Prolonged distal motor latency of median nerve does not improve diagnostic accuracy for CIDP

Journal of Neurology - Compression of the median nerve at the carpal tunnel can give demyelinating features and result in distal motor latency (DML) prolongation fulfilling the EFNS/PNS...     

Validation of the DYALS (dysphagia in amyotrophic lateral sclerosis) questionnaire for the evaluation of dysphagia in ALS patients

Neurological Sciences - Dysphagia is a common symptom during the trajectory of ALS, and it can significantly impact on the quality of life and prognosis of patients. Nowadays, no specific tool for...     

Myoclonus in mitochondrial disorders

Myoclonus is a possible manifestation of mitochondrial disorders, and its presence is considered, in association with epilepsy and the ragged red fibers, pivotal for the syndromic diagnosis of MERRF (myoclonic epilepsy with ragged red fibers). However, its prevalence in mitochondrial diseases is not known. The aims of this study are the evaluation of the prevalence of myoclonus in a big cohort of mitochondrial patients and the clinical characterization of these subjects. Based on the database of the “Nation‐wide Italian Collaborative Network of Mitochondrial Diseases,” we reviewed the clinical and molecular data of mitochondrial patients with myoclonus among their clinical features. Myoclonus is a rather uncommon clinical feature of mitochondrial diseases (3.6% of 1,086 patients registered in our database). It is not strictly linked to a specific genotype or phenotype, and only 1 of 3 patients with MERRF harbors the 8344A>G mutation (frequently labeled as “the MERRF mutation”). Finally, myoclonus is not inextricably linked to epilepsy in MERRF patients, but more to cerebellar ataxia. In a myoclonic patient, evidences of mitochondrial dysfunction must be investigated, even though myoclonus is not a common sign of mitochondriopathy. Clinical, histological, and biochemical data may predict the finding of a mitochondrial or nuclear DNA mutation. Finally, this study reinforces the notion that myoclonus is not inextricably linked to epilepsy in MERRF patients, and therefore the term “myoclonic epilepsy” seems inadequate and potentially misleading. © 2014 International Parkinson and Movement Disorder Society     

Subcutaneous immunoglobulin in CIDP and MMN: a short-term nationwide study

This multi-center Italian prospective observational study reports the 4 months follow-up data of 87 patients affected by chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and multifocal motor neuropathy (MMN) shifted from intravenous to subcutaneous immunoglobulin treatment. A therapeutic shift from intravenous to subcutaneous immunoglobulin was performed in 87 patients (66 CIDP; 21 MMN) affected by immune-mediated peripheral neuropathies with evidence of a sustained clinical response to intravenous immunoglobulin. Patients were evaluated by means of the Overall Neuropathy Limitation Scale, Medical Research Council Scale and Life Quality Index questionnaire, both at the time of therapeutic shift and after 4 months of subcutaneous immunoglobulin treatment. A sustained clinical efficacy was observed after the switch to subcutaneous immunoglobulin: the Overall Neuropathy Limitation Scale score improved in the group of 66 CIDP patients (P = 0.018), with only one subject reporting a worsening of 1 point, and remained stable in the group of 21 MMN patients (P = 0.841), with one subject reporting a worsening of two points. An improvement in the patient’s perception of therapeutic setting was reported in both groups. This large multi-center study confirms the short-term clinical equivalence of subcutaneous versus intravenous immunoglobulin and a possible improvement in the patient’s perception of therapeutic setting with the subcutaneous administration. However, further studies are required to extend the results to a longer observational period.