ABSTRACT
Biallelic intronic repeat expansion in the replication factor complex unit 1 (RFC1) gene has recently been described as a cause of late onset ataxia with degeneration of the cerebellum, sensory pathways and the vestibular apparatus. This condition is termed cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS). Since the identification of this novel gene mutation, the phenotypic spectrum of RFC1 mutations continues to expand and includes not only CANVAS but also slowly progressive cerebellar ataxia, ataxia with chronic cough (ACC), isolated sensory neuropathy and multisystemic diseases. We present a patient with a genetically confirmed intronic repeat expansion in the RFC1 gene with a symptom complex not described previously.
ABSTRACT
Scientific and technological advances achieved with industrial expansion have led to an ever-increasing demand for heavy metals. This demand has, in turn, led to increased contamination of soil, water and air with these metals. Chronic exposure to metals may be detrimental not only to occupational workers but also to the nonoccupational population exposed to these metals. Manganese (Mn), a commonly used heavy metal, is an essential cofactor for many enzymatic processes that drive biological functions. However, it is also a potential source of neurotoxicity, particularly in the field of movement disorders. The typical manifestation of Mn overexposure is parkinsonism, which may be difficult to differentiate from the more common idiopathic Parkinson’s disease. In addition to environmental exposure to Mn, other potential etiologies causing hypermanganesemia include systemic health conditions, total parenteral nutrition and genetic mutations causing Mn dyshomeostasis. In this review, we critically analyze Mn and discuss its sources of exposure, pathophysiology and clinical manifestations. We have highlighted the global public health impact of Mn and emphasize that movement disorder specialists should record a detailed social and occupational history to ensure that a toxic etiology is not misdiagnosed as a neurodegenerative disease. In the absence of a definite therapeutic option, early diagnosis and timely institution of preventive measures are the keys to managing its toxic effects.
ABSTRACT
Scientific and technological advances achieved with industrial expansion have led to an ever-increasing demand for heavy metals. This demand has, in turn, led to increased contamination of soil, water and air with these metals. Chronic exposure to metals may be detrimental not only to occupational workers but also to the nonoccupational population exposed to these metals. Manganese (Mn), a commonly used heavy metal, is an essential cofactor for many enzymatic processes that drive biological functions. However, it is also a potential source of neurotoxicity, particularly in the field of movement disorders. The typical manifestation of Mn overexposure is parkinsonism, which may be difficult to differentiate from the more common idiopathic Parkinson’s disease. In addition to environmental exposure to Mn, other potential etiologies causing hypermanganesemia include systemic health conditions, total parenteral nutrition and genetic mutations causing Mn dyshomeostasis. In this review, we critically analyze Mn and discuss its sources of exposure, pathophysiology and clinical manifestations. We have highlighted the global public health impact of Mn and emphasize that movement disorder specialists should record a detailed social and occupational history to ensure that a toxic etiology is not misdiagnosed as a neurodegenerative disease. In the absence of a definite therapeutic option, early diagnosis and timely institution of preventive measures are the keys to managing its toxic effects.
ABSTRACT
Epilepsy in Duchene’s muscular dystrophy, though more prevalent than in general population, is seen in only 6-10% cases of DMD. Earlier studies have reported nonspecific MRI findings in DMD patients with epilepsy. We report a patient of DMD, diagnosed on muscle biopsy who had definite MRI brain imaging abnormalities. Our case highlights the rare association of MRI brain signal changes in this patient with DMD.