Elemental mercury poisoning probably causes cortical myoclonus.
Mercury toxicity causes postural tremors, commonly referred to as "mercurial tremors," and cerebellar dysfunction. A 23-year woman, 2 years after injecting herself with elemental mercury developed disabling generalized myoclonus and ataxia. Electrophysiological studies confirmed the myoclonus was probably of cortical origin. Her deficits progressed over 2 years and improved after subcutaneous mercury deposits at the injection site were surgically cleared. Myoclonus of cortical origin has never been described in mercury poisoning. It is important to ask patients presenting with jerks about exposure to elemental mercury even if they have a progressive illness, as it is a potentially reversible condition as in our patient.
Ragothaman
Mona
M
Department of Neurology, National Institute of Mental Health & Neurosciences, Bangalore, India.
Kulkarni
Girish
G
Ashraf
Valappil V
VV
Pal
Pramod K
PK
Chickabasavaiah
Yasha
Y
Shankar
Susarla K
SK
Govindappa
Srikanth S
SS
Satishchandra
Parthasarthy
P
Muthane
Uday B
UB
D000328:Adult; D002524:Cerebellar Ataxia / Q000139:chemically induced* / Q000175:diagnosis; D002540:Cerebral Cortex / Q000187:drug effects*; D018450:Disease Progression; D004401:Dysarthria / Q000139:chemically induced / Q000175:diagnosis; D004576:Electromyography / Q000187:drug effects; D004830:Epilepsy, Tonic-Clonic / Q000139:chemically induced / Q000175:diagnosis; D005073:Evoked Potentials, Somatosensory / Q000187:drug effects; D005260:Female; D005547:Foreign Bodies / Q000473:pathology; D015743:Giant Cells, Foreign-Body / Q000473:pathology; D006801:Humans; D007275:Injections, Intravenous; D008628:Mercury / Q000008:administration & dosage; D008630:Mercury Poisoning / Q000175:diagnosis* / Q000473:pathology; D009207:Myoclonus / Q000139:chemically induced* / Q000175:diagnosis; D011596:Psychomotor Disorders / Q000139:chemically induced / Q000175:diagnosis; D012867:Skin / Q000187:drug effects / Q000473:pathology
D008628:Mercury