Opsoclonus myoclonus syndrome (OMS), also known as opsoclonus-myoclonus-ataxia (OMA), is a rare neurological disorder of unknown cause which appears to be the result of an autoimmune process involving the nervous system. It is an extremely rare condition, affecting as few as 1 in 10,000,000 people per year. It affects 2 to 3% of children with neuroblastoma and has been reported to occur with celiac disease and diseases of neurologic and autonomic dysfunction. Signs and symptoms
Symptoms include:
opsoclonus (rapid, involuntary, multivectorial (horizontal and vertical), unpredictable, conjugate fast eye movements without intersaccadic [quick rotation of the eyes] intervals)
myoclonus (brief, involuntary twitching of a muscle or a group of muscles)
cerebellar ataxia, both truncal and appendicular
aphasia (a language disorder in which there is an impairment of speech and of comprehension of speech, caused by brain damage)
mutism (a language disorder in which a person does not speak despite evidence of speech ability in the past, often part of a larger neurological or psychiatric disorder)
lethargy
irritability or malaise
drooling
strabismus (a condition in which the eyes are not properly aligned with each other)
vomiting
sleep disturbances
emotional disturbances (including fits of rage)About half of all OMS cases occur in association with neuroblastoma (a cancer of the sympathetic nervous system usually occurring in infants and children). Disease course and clinical subtypes
In most cases, OMS starts with an acute flare-up of physical symptoms within days or weeks, but some less obvious symptoms such as irritability and malaise may begin weeks or months earlier.
By 1954, it was found that the mutant hemoglobin was highly prevalent in West Africa. In 1960, Vernon Ingram and J. A. Hunt at the University of Cambridge discovered that the mutation was a single amino acid replacement of glutamic acid with lysine. References
External links
Hemoglobin+C at the US National Library of Medicine Medical Subject Headings (MeSH)
Hemoglobin+C+Disease at the US National Library of Medicine Medical Subject Headings (MeSH)