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Myoclonus, intractable, neonatal(NEIMY)

MedGen UID:
934625
Concept ID:
C4310658
Disease or Syndrome
Synonym: NEIMY
 
Gene (location): KIF5A (12q13.3)
 
Monarch Initiative: MONDO:0014979
OMIM®: 617235

Definition

Neonatal intractable myoclonus (NEIMY) is a severe neurologic disorder characterized by the onset of intractable myoclonic seizures soon after birth. Affected infants have intermittent apnea, abnormal eye movements, pallor of the optic nerve, and lack of developmental progress. Brain imaging shows a progressive leukoencephalopathy. Some patients may die in infancy. There is phenotypic and biochemical evidence of mitochondrial dysfunction (summary by Duis et al., 2016). [from OMIM]

Clinical features

From HPO
Dysphagia
MedGen UID:
41440
Concept ID:
C0011168
Disease or Syndrome
Difficulty in swallowing.
Feeding difficulties
MedGen UID:
65429
Concept ID:
C0232466
Finding
Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it.
Poor suck
MedGen UID:
324693
Concept ID:
C1837142
Finding
An inadequate sucking reflex, resulting in the difficult of newborns to be breast-fed.
Impaired oral bolus formation
MedGen UID:
1386273
Concept ID:
C4477005
Finding
An abnormality of swallowing characterized by reduced tongue coordination to form bolus after chewing. Food material spreads over the oral cavity instead of being concentrated into a bolus that is easily swallowed.
Athetosis
MedGen UID:
2115
Concept ID:
C0004158
Disease or Syndrome
A slow, continuous, involuntary writhing movement that prevents maintenance of a stable posture. Athetosis involves continuous smooth movements that appear random and are not composed of recognizable sub-movements or movement fragments. In contrast to chorea, in athetosis, the same regions of the body are repeatedly involved. Athetosis may worsen with attempts at movement of posture, but athetosis can also occur at rest.
Chorea
MedGen UID:
3420
Concept ID:
C0008489
Disease or Syndrome
Chorea (Greek for 'dance') refers to widespread arrhythmic involuntary movements of a forcible, jerky and restless fashion. It is a random-appearing sequence of one or more discrete involuntary movements or movement fragments. Movements appear random because of variability in timing, duration or location. Each movement may have a distinct start and end. However, movements may be strung together and thus may appear to flow randomly from one muscle group to another. Chorea can involve the trunk, neck, face, tongue, and extremities.
Myoclonus
MedGen UID:
10234
Concept ID:
C0027066
Finding
Very brief, involuntary random muscular contractions occurring at rest, in response to sensory stimuli, or accompanying voluntary movements.
Clonic seizure
MedGen UID:
66708
Concept ID:
C0234535
Disease or Syndrome
A clonic seizure is a type of motor seizure characterized by sustained rhythmic jerking, that is regularly repetitive.
Hypoplasia of the corpus callosum
MedGen UID:
138005
Concept ID:
C0344482
Congenital Abnormality
Underdevelopment of the corpus callosum.
Global developmental delay
MedGen UID:
107838
Concept ID:
C0557874
Finding
A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.
Progressive leukoencephalopathy
MedGen UID:
344402
Concept ID:
C1855010
Finding
Leukoencephalopathy that gets more severe with time.
Delayed CNS myelination
MedGen UID:
867393
Concept ID:
C4021758
Anatomical Abnormality
Delayed myelination in the central nervous system.
Hypotonia
MedGen UID:
10133
Concept ID:
C0026827
Finding
Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist.
Increased variability in muscle fiber diameter
MedGen UID:
336019
Concept ID:
C1843700
Finding
An abnormally high degree of muscle fiber size variation. This phenotypic feature can be observed upon muscle biopsy.
Dandy-Walker malformation
MedGen UID:
419183
Concept ID:
C2931867
Congenital Abnormality
A congenital brain malformation typically characterized by incomplete formation of the cerebellar vermis, dilation of the fourth ventricle, and enlargement of the posterior fossa. In layman's terms, Dandy Walker malformation is a cyst in the cerebellum (typically symmetrical) that is involved with the fourth ventricle. This may interfere with the ability to drain cerebrospinal fluid from the brain, resulting in hydrocephalus. Dandy Walker cysts are formed during early embryonic development, while the brain forms. The cyst in the cerebellum typically has several blood vessels running through it connecting to the brain, thereby prohibiting surgical removal.
Microcephaly
MedGen UID:
1644158
Concept ID:
C4551563
Finding
Head circumference below 2 standard deviations below the mean for age and gender.
Apnea
MedGen UID:
2009
Concept ID:
C0003578
Sign or Symptom
Lack of breathing with no movement of the respiratory muscles and no exchange of air in the lungs. This term refers to a disposition to have recurrent episodes of apnea rather than to a single event.
Ptosis
MedGen UID:
2287
Concept ID:
C0005745
Disease or Syndrome
The upper eyelid margin is positioned 3 mm or more lower than usual and covers the superior portion of the iris (objective); or, the upper lid margin obscures at least part of the pupil (subjective).
Horizontal nystagmus
MedGen UID:
124399
Concept ID:
C0271385
Disease or Syndrome
Nystagmus consisting of horizontal to-and-fro eye movements.
Optic disc pallor
MedGen UID:
108218
Concept ID:
C0554970
Finding
A pale yellow discoloration of the optic disc (the area of the optic nerve head in the retina). The optic disc normally has a pinkish hue with a central yellowish depression.
Cerebral visual impairment
MedGen UID:
890568
Concept ID:
C4048268
Pathologic Function
A form of loss of vision caused by damage to the visual cortex rather than a defect in the eye.

Professional guidelines

PubMed

de Boer EMJ, van Rheenen W, Goedee HS, Kamsteeg EJ, Brilstra EH, Veldink JH, van Den Berg LH, van Es MA
Amyotroph Lateral Scler Frontotemporal Degener 2021 Nov;22(7-8):561-570. Epub 2021 Apr 8 doi: 10.1080/21678421.2021.1907412. PMID: 33829936

Recent clinical studies

Etiology

Camfield P, Camfield C
Epilepsia 2007 Jun;48(6):1128-32. Epub 2007 Apr 18 doi: 10.1111/j.1528-1167.2007.01072.x. PMID: 17442010

Diagnosis

Kashiki T, Kido J, Momosaki K, Kusunoki S, Ozasa S, Nomura K, Imai-Okazaki A, Tsuruoka T, Murayama K, Koga Y, Nakamura K
Brain Dev 2022 Jan;44(1):56-62. Epub 2021 Aug 25 doi: 10.1016/j.braindev.2021.08.005. PMID: 34452803
Takeda K, Miyamoto Y, Yamamoto H, Ishii A, Hirose S, Yamamoto H
Brain Dev 2020 Jan;42(1):73-76. Epub 2019 Sep 3 doi: 10.1016/j.braindev.2019.08.003. PMID: 31492455
Veerapandiyan A, Winchester SA, Gallentine WB, Smith EC, Kansagra S, Hyland K, Mikati MA
Epilepsy Behav 2011 Mar;20(3):494-501. Epub 2011 Feb 2 doi: 10.1016/j.yebeh.2010.12.046. PMID: 21292558
Camfield P, Camfield C
Epilepsia 2007 Jun;48(6):1128-32. Epub 2007 Apr 18 doi: 10.1111/j.1528-1167.2007.01072.x. PMID: 17442010
Ohtsuka Y, Tanaka A, Kobayashi K, Ohta H, Abiru K, Nakano K, Oka E
Brain Dev 2002 Dec;24(8):758-65. doi: 10.1016/s0387-7604(02)00099-2. PMID: 12453599

Therapy

Kosaka T, Ohta G, Kometani H, Kawatani M, Ohshima Y
Brain Dev 2019 Sep;41(8):717-720. Epub 2019 Apr 23 doi: 10.1016/j.braindev.2019.04.007. PMID: 31027651
Nakano K, Kobayashi K, Maniwa S, Kodani N, Ohtsuka Y
Epileptic Disord 2013 Sep;15(3):352-7. doi: 10.1684/epd.2013.0593. PMID: 23886871
Cusmai R, Martinelli D, Moavero R, Dionisi Vici C, Vigevano F, Castana C, Elia M, Bernabei S, Bevivino E
Eur J Paediatr Neurol 2012 Sep;16(5):509-13. Epub 2012 Jan 18 doi: 10.1016/j.ejpn.2011.12.015. PMID: 22261077
Veerapandiyan A, Winchester SA, Gallentine WB, Smith EC, Kansagra S, Hyland K, Mikati MA
Epilepsy Behav 2011 Mar;20(3):494-501. Epub 2011 Feb 2 doi: 10.1016/j.yebeh.2010.12.046. PMID: 21292558

Prognosis

Brenner D, Yilmaz R, Müller K, Grehl T, Petri S, Meyer T, Grosskreutz J, Weydt P, Ruf W, Neuwirth C, Weber M, Pinto S, Claeys KG, Schrank B, Jordan B, Knehr A, Günther K, Hübers A, Zeller D, Kubisch C, Jablonka S, Sendtner M, Klopstock T, de Carvalho M, Sperfeld A, Borck G, Volk AE, Dorst J, Weis J, Otto M, Schuster J, Del Tredici K, Braak H, Danzer KM, Freischmidt A, Meitinger T, Strom TM, Ludolph AC, Andersen PM, Weishaupt JH; German ALS network MND-NET
Brain 2018 Mar 1;141(3):688-697. doi: 10.1093/brain/awx370. PMID: 29342275Free PMC Article
Camfield P, Camfield C
Epilepsia 2007 Jun;48(6):1128-32. Epub 2007 Apr 18 doi: 10.1111/j.1528-1167.2007.01072.x. PMID: 17442010
Kato M, Dobyns WB
J Child Neurol 2005 Apr;20(4):392-7. doi: 10.1177/08830738050200042001. PMID: 15921244
Ohtsuka Y, Tanaka A, Kobayashi K, Ohta H, Abiru K, Nakano K, Oka E
Brain Dev 2002 Dec;24(8):758-65. doi: 10.1016/s0387-7604(02)00099-2. PMID: 12453599

Clinical prediction guides

Cozzi M, Magri S, Tedesco B, Patelli G, Ferrari V, Casarotto E, Chierichetti M, Pramaggiore P, Cornaggia L, Piccolella M, Galbiati M, Rusmini P, Crippa V, Mandrioli J, Pareyson D, Pisciotta C, D'Arrigo S, Ratti A, Nanetti L, Mariotti C, Sarto E, Pensato V, Gellera C, Di Bella D, Cristofani RM, Taroni F, Poletti A
Cell Death Dis 2024 Sep 27;15(9):692. doi: 10.1038/s41419-024-07096-5. PMID: 39333504Free PMC Article
Takeda K, Miyamoto Y, Yamamoto H, Ishii A, Hirose S, Yamamoto H
Brain Dev 2020 Jan;42(1):73-76. Epub 2019 Sep 3 doi: 10.1016/j.braindev.2019.08.003. PMID: 31492455
Brenner D, Yilmaz R, Müller K, Grehl T, Petri S, Meyer T, Grosskreutz J, Weydt P, Ruf W, Neuwirth C, Weber M, Pinto S, Claeys KG, Schrank B, Jordan B, Knehr A, Günther K, Hübers A, Zeller D, Kubisch C, Jablonka S, Sendtner M, Klopstock T, de Carvalho M, Sperfeld A, Borck G, Volk AE, Dorst J, Weis J, Otto M, Schuster J, Del Tredici K, Braak H, Danzer KM, Freischmidt A, Meitinger T, Strom TM, Ludolph AC, Andersen PM, Weishaupt JH; German ALS network MND-NET
Brain 2018 Mar 1;141(3):688-697. doi: 10.1093/brain/awx370. PMID: 29342275Free PMC Article
Ohtsuka Y, Tanaka A, Kobayashi K, Ohta H, Abiru K, Nakano K, Oka E
Brain Dev 2002 Dec;24(8):758-65. doi: 10.1016/s0387-7604(02)00099-2. PMID: 12453599

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