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Myoclonic spasms

MedGen UID:
812772
Concept ID:
C3806442
Finding
HPO: HP:0003739

Term Hierarchy

Conditions with this feature

Stiff-man syndrome
MedGen UID:
39017
Concept ID:
C0085292
Disease or Syndrome
The stiff-person syndrome (SPS) is most often an adult-onset sporadic acquired disorder characterized by progressive muscle stiffness with superimposed painful muscle spasms accompanied by electromyographic evidence of continuous motor activity at rest. SPS has been associated with autoimmune disorders, diabetes mellitus, thyrotoxicosis, and hypopituitarism with adrenal insufficiency (George et al., 1984). Approximately 60% of patients with SPS have antibodies to glutamic acid decarboxylase (GAD2, or GAD65; 138275), the rate-limiting enzyme in the synthesis of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), suggesting an immune-mediated pathogenesis (Folli et al., 1993). Approximately 10% of patients develop SPS as a paraneoplastic neurologic disorder associated with antibodies to amphiphysin (AMPH; 600418), an intracellular protein associated with neuronal synaptic vesicle endocytosis (Burns, 2005). See also congenital stiff-man syndrome, or hereditary hyperexplexia (149400), which is caused by mutations in subunits of the glycine receptor gene (GLRA1, 138491; GLRB, 138492). Meinck and Thompson (2002) provided a detailed review of stiff-person syndrome. They also discussed 2 possibly related conditions, progressive encephalomyelitis with rigidity (PERM), a more severe disorder with other neurologic features, and stiff-limb or stiff-leg syndrome, a focal disorder.
Sulfite oxidase deficiency due to molybdenum cofactor deficiency type A
MedGen UID:
381530
Concept ID:
C1854988
Disease or Syndrome
Molybdenum cofactor deficiency (MoCD) represents a spectrum, with some individuals experiencing significant signs and symptoms in the neonatal period and early infancy (termed early-onset or severe MoCD) and others developing signs and symptoms in childhood or adulthood (termed late-onset or mild MoCD). Individuals with early-onset MoCD typically present in the first days of life with severe encephalopathy, including refractory seizures, opisthotonos, axial and appendicular hypotonia, feeding difficulties, and apnea. Head imaging may demonstrate loss of gray and white matter differentiation, gyral swelling, sulci injury (typically assessed by evaluating the depth of focal lesional injury within the sulci), diffusely elevated T2-weighted signal, and panlobar diffusion restriction throughout the forebrain and midbrain with relative sparring of the brain stem. Prognosis for early-onset MoCD is poor, with about 75% succumbing in infancy to secondary complications of their neurologic disability (i.e., pneumonia). Late-onset MoCD is typically characterized by milder symptoms, such as acute neurologic decompensation in the setting of infection. Episodes vary in nature but commonly consist of altered mental status, dystonia, choreoathetosis, ataxia, nystagmus, and fluctuating hypotonia and hypertonia. These features may improve after resolution of the inciting infection or progress in a gradual or stochastic manner over the lifetime. Brain imaging may be normal or may demonstrate T2-weighted hyperintense or cystic lesions in the globus pallidus, thinning of the corpus callosum, and cerebellar atrophy.
Sulfite oxidase deficiency due to molybdenum cofactor deficiency type B
MedGen UID:
340760
Concept ID:
C1854989
Disease or Syndrome
Molybdenum cofactor deficiency (MoCD) represents a spectrum, with some individuals experiencing significant signs and symptoms in the neonatal period and early infancy (termed early-onset or severe MoCD) and others developing signs and symptoms in childhood or adulthood (termed late-onset or mild MoCD). Individuals with early-onset MoCD typically present in the first days of life with severe encephalopathy, including refractory seizures, opisthotonos, axial and appendicular hypotonia, feeding difficulties, and apnea. Head imaging may demonstrate loss of gray and white matter differentiation, gyral swelling, sulci injury (typically assessed by evaluating the depth of focal lesional injury within the sulci), diffusely elevated T2-weighted signal, and panlobar diffusion restriction throughout the forebrain and midbrain with relative sparring of the brain stem. Prognosis for early-onset MoCD is poor, with about 75% succumbing in infancy to secondary complications of their neurologic disability (i.e., pneumonia). Late-onset MoCD is typically characterized by milder symptoms, such as acute neurologic decompensation in the setting of infection. Episodes vary in nature but commonly consist of altered mental status, dystonia, choreoathetosis, ataxia, nystagmus, and fluctuating hypotonia and hypertonia. These features may improve after resolution of the inciting infection or progress in a gradual or stochastic manner over the lifetime. Brain imaging may be normal or may demonstrate T2-weighted hyperintense or cystic lesions in the globus pallidus, thinning of the corpus callosum, and cerebellar atrophy.
Neonatal-onset encephalopathy with rigidity and seizures
MedGen UID:
482659
Concept ID:
C3281029
Disease or Syndrome
Lethal neonatal rigidity and multifocal seizure syndrome (RMFSL) is a severe autosomal recessive epileptic encephalopathy characterized by onset of rigidity and intractable seizures at or soon after birth. Affected infants achieve no developmental milestones and die within the first months or years of life (summary by Saitsu et al., 2014).

Professional guidelines

PubMed

Auvin S
Rev Neurol (Paris) 2016 Mar;172(3):182-5. Epub 2016 Mar 15 doi: 10.1016/j.neurol.2015.12.009. PMID: 26993568
Holdsworth MT, Adams VR, Chavez CM, Vaughan LJ, Duncan MH
Ann Pharmacother 1995 Jan;29(1):25-9. doi: 10.1177/106002809502900105. PMID: 7711342
Vince JD
P N G Med J 1992 Jun;35(2):144-51. PMID: 1509814

Recent clinical studies

Diagnosis

Alimohammadi H, Abdalvand A, Safari S, Mazinanian A
Am J Emerg Med 2012 Nov;30(9):2092.e1-3. Epub 2012 Mar 3 doi: 10.1016/j.ajem.2011.12.034. PMID: 22386347
Sie SD, de Jonge RC, Blom HJ, Mulder MF, Reiss J, Vermeulen RJ, Peeters-Scholte CM
J Inherit Metab Dis 2010 Dec;33 Suppl 3(Suppl 3):S401-7. Epub 2010 Sep 24 doi: 10.1007/s10545-010-9198-z. PMID: 20865336Free PMC Article
Mozley PD
Diagn Gynecol Obstet 1981 Spring;3(1):81-6. PMID: 7011755
Hirashima Y, Shinozuka S, Ieiri T, Matsuda I, Ono Y, Murata T
Eur J Pediatr 1979 Jan 18;130(1):41-5. doi: 10.1007/BF00441897. PMID: 759181
Barry JF, Harwood-Nash DC, Fitz CR, Byrd SE, Boldt DW
Radiology 1977 Aug;124(2):409-18. doi: 10.1148/124.2.409. PMID: 877281

Therapy

Alimohammadi H, Abdalvand A, Safari S, Mazinanian A
Am J Emerg Med 2012 Nov;30(9):2092.e1-3. Epub 2012 Mar 3 doi: 10.1016/j.ajem.2011.12.034. PMID: 22386347
Killeffer JA, Kaufman HH
Surg Neurol 1997 Jul;48(1):70-3. doi: 10.1016/s0090-3019(96)00156-5. PMID: 9199689
Glavina MJ, Robertshaw R
Anaesthesia 1988 May;43(5):389-90. doi: 10.1111/j.1365-2044.1988.tb09020.x. PMID: 3400849
Mozley PD
Diagn Gynecol Obstet 1981 Spring;3(1):81-6. PMID: 7011755
Barry JF, Harwood-Nash DC, Fitz CR, Byrd SE, Boldt DW
Radiology 1977 Aug;124(2):409-18. doi: 10.1148/124.2.409. PMID: 877281

Prognosis

Alimohammadi H, Abdalvand A, Safari S, Mazinanian A
Am J Emerg Med 2012 Nov;30(9):2092.e1-3. Epub 2012 Mar 3 doi: 10.1016/j.ajem.2011.12.034. PMID: 22386347
Sie SD, de Jonge RC, Blom HJ, Mulder MF, Reiss J, Vermeulen RJ, Peeters-Scholte CM
J Inherit Metab Dis 2010 Dec;33 Suppl 3(Suppl 3):S401-7. Epub 2010 Sep 24 doi: 10.1007/s10545-010-9198-z. PMID: 20865336Free PMC Article

Clinical prediction guides

Sie SD, de Jonge RC, Blom HJ, Mulder MF, Reiss J, Vermeulen RJ, Peeters-Scholte CM
J Inherit Metab Dis 2010 Dec;33 Suppl 3(Suppl 3):S401-7. Epub 2010 Sep 24 doi: 10.1007/s10545-010-9198-z. PMID: 20865336Free PMC Article
TUCKER JS, SOLITARE GB
Epilepsia 1963 Mar;4:45-59. doi: 10.1111/j.1528-1157.1963.tb05207.x. PMID: 13994695

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