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Neurodevelopmental disorder with microcephaly, seizures, and brain atrophy(NEDMISB)

MedGen UID:
1755716
Concept ID:
C5436747
Disease or Syndrome
Synonyms: NEDMISB; NEURODEVELOPMENTAL DISORDER WITH MICROCEPHALY, SEIZURES, AND BRAIN ATROPHY
 
Gene (location): EXOC8 (1q42.2)
 
Monarch Initiative: MONDO:0033662
OMIM®: 619076

Definition

Neurodevelopmental disorder with microcephaly, seizures, and brain atrophy (NEDMISB) is an autosomal recessive disorder characterized by severe global developmental delay, developmental regression with loss of milestones, severe microcephaly, and brain abnormalities, primarily cerebral atrophy and hypoplasia of the corpus callosum. Affected individuals develop seizures in the first year of life; eventually they are unable to sit, feed, or communicate, and may be unresponsive to stimuli. Other features include muscle weakness, spasticity with hyperreflexia, irritability, and contractures (Coulter et al., 2020). [from OMIM]

Clinical features

From HPO
Spasticity
MedGen UID:
7753
Concept ID:
C0026838
Sign or Symptom
A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes.
Seizure
MedGen UID:
20693
Concept ID:
C0036572
Sign or Symptom
A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.
Hyperreflexia
MedGen UID:
57738
Concept ID:
C0151889
Finding
Hyperreflexia is the presence of hyperactive stretch reflexes of the muscles.
Choroid plexus cyst
MedGen UID:
87376
Concept ID:
C0338597
Finding
A cyst occurring within the choroid plexus within a cerebral ventricle.
Hypoplasia of the corpus callosum
MedGen UID:
138005
Concept ID:
C0344482
Congenital Abnormality
Underdevelopment of the corpus callosum.
Hypsarrhythmia
MedGen UID:
195766
Concept ID:
C0684276
Finding
Hypsarrhythmia is abnormal interictal high amplitude waves and a background of irregular spikes. There is continuous (during wakefulness), high-amplitude (>200 Hz), generalized polymorphic slowing with no organized background and multifocal spikes demonstrated by electroencephalography (EEG).
Severe global developmental delay
MedGen UID:
332436
Concept ID:
C1837397
Finding
A severe delay in the achievement of motor or mental milestones in the domains of development of a child.
Irritability
MedGen UID:
397841
Concept ID:
C2700617
Mental Process
A proneness to anger, i.e., a tendency to become easily bothered or annoyed.
Delayed CNS myelination
MedGen UID:
867393
Concept ID:
C4021758
Anatomical Abnormality
Delayed myelination in the central nervous system.
Myoclonic seizure
MedGen UID:
1385980
Concept ID:
C4317123
Sign or Symptom
A myoclonic seizure is a type of motor seizure characterized by sudden, brief (<100 ms) involuntary single or multiple contraction of muscles or muscle groups of variable topography (axial, proximal limb, distal). Myoclonus is less regularly repetitive and less sustained than is clonus.
Bilateral tonic-clonic seizure with generalized onset
MedGen UID:
1368929
Concept ID:
C4476643
Sign or Symptom
A bilateral tonic-clonic seizure with generalized onset is a type of bilateral tonic-clonic seizure characterized by generalized onset; these seizures rapidly engage networks in both hemispheres at the start of the seizure.
Brain atrophy
MedGen UID:
1643639
Concept ID:
C4551584
Disease or Syndrome
Partial or complete wasting (loss) of brain tissue that was once present.
Craniosynostosis syndrome
MedGen UID:
1163
Concept ID:
C0010278
Disease or Syndrome
Craniosynostosis refers to the premature closure of the cranial sutures. Primary craniosynostosis refers to the closure of one or more sutures due to abnormalities in skull development, and secondary craniosynostosis results from failure of brain growth.
Hypertonia
MedGen UID:
10132
Concept ID:
C0026826
Finding
A condition in which there is increased muscle tone so that arms or legs, for example, are stiff and difficult to move.
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.
Muscle weakness
MedGen UID:
57735
Concept ID:
C0151786
Finding
Reduced strength of muscles.
Flexion contracture
MedGen UID:
83069
Concept ID:
C0333068
Anatomical Abnormality
A flexion contracture is a bent (flexed) joint that cannot be straightened actively or passively. It is thus a chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevents normal movement of joints.
Microcephaly
MedGen UID:
1644158
Concept ID:
C4551563
Finding
Head circumference below 2 standard deviations below the mean for age and gender.
Round face
MedGen UID:
116087
Concept ID:
C0239479
Finding
The facial appearance is more circular than usual as viewed from the front.
Long eyelashes
MedGen UID:
342955
Concept ID:
C1853738
Finding
Mid upper eyelash length >10 mm or increased length of the eyelashes (subjective).
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).
Exotropia
MedGen UID:
4613
Concept ID:
C0015310
Disease or Syndrome
A form of strabismus with one or both eyes deviated outward.
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.

Professional guidelines

PubMed

Almannai M, Marafi D, Abdel-Salam GMH, Zaki MS, Duan R, Calame D, Herman I, Levesque F, Elbendary HM, Hegazy I, Chung WK, Kavus H, Saeidi K, Maroofian R, AlHashim A, Al-Otaibi A, Al Madhi A, Abou Al-Seood HM, Alasmari A, Houlden H, Gleeson JG, Hunter JV, Posey JE, Lupski JR, El-Hattab AW
Clin Genet 2022 May;101(5-6):530-540. Epub 2022 Apr 12 doi: 10.1111/cge.14132. PMID: 35322404Free PMC Article

Recent clinical studies

Etiology

Ivanov I, Pacheva I, Yordanova R, Sotkova I, Galabova F, Gaberova K, Panova M, Gheneva I, Tsvetanova T, Noneva K, Dimitrova D, Markov S, Sapundzhiev N, Bichev S, Savov A
CNS Neurol Disord Drug Targets 2023;22(2):207-214. doi: 10.2174/1871527321666220221100704. PMID: 35189806
Giacomini T, Nuovo S, Zanni G, Mancardi MM, Cusmai R, Pepi C, Bertini E, Valente EM, Battini R, Ferrari A, Romaniello R, Zucca C, Borgatti R, Uccella S, Severino M, Striano P, Pistorio A, Prato G, De Grandis E, Nobili L, Pisciotta L
Eur J Paediatr Neurol 2021 Mar;31:61-69. Epub 2021 Feb 19 doi: 10.1016/j.ejpn.2021.02.006. PMID: 33640666
Alharby E, Faqeih EA, Saleh M, Alameer S, Almuntashri M, Pastore A, Samman MA, Alnawfal AM, Hashem M, Zaytuni D, Alharbi G, Almannai M, Alasmari A, Mahmoud AA, Alwadei AH, Jad L, AlOtaibi A, Al-Hakami F, Eyaid W, Alkuraya FS, Alfadhel M, Peake RWA, Almontashiri NAM
Genet Med 2020 Dec;22(12):2071-2080. Epub 2020 Aug 3 doi: 10.1038/s41436-020-0919-x. PMID: 32741967
Borlot F, Abushama A, Morrison-Levy N, Jain P, Puthenveettil Vinayan K, Abukhalid M, Aldhalaan HM, Almuzaini HS, Gulati S, Hershkovitz T, Konanki R, Lingappa L, Luat AF, Shafi S, Tabarki B, Thomas M, Yoganathan S, Alfadhel M, Arya R, Donner EJ, Ehaideb SN, Gowda VK, Jain V, Madaan P, Myers KA, Otsubo H, Panda P, Sahu JK, Sampaio LPB, Sharma S, Simard-Tremblay E, Zak M, Whitney R
Epilepsia 2020 Apr;61(4):679-692. Epub 2020 Mar 13 doi: 10.1111/epi.16480. PMID: 32167590
Jurecka A, Jurkiewicz E, Tylki-Szymanska A
Eur J Pediatr 2012 Jan;171(1):131-8. Epub 2011 May 31 doi: 10.1007/s00431-011-1503-9. PMID: 21625931

Diagnosis

Karaer K, Karaer D, Yüksel Z, Işikay S
Clin Dysmorphol 2022 Oct 1;31(4):167-173. Epub 2022 Jul 14 doi: 10.1097/MCD.0000000000000426. PMID: 36004946
Schneeberger PE, Nampoothiri S, Holling T, Yesodharan D, Alawi M, Knisely AS, Müller T, Plecko B, Janecke AR, Kutsche K
Brain 2021 Nov 29;144(10):3036-3049. doi: 10.1093/brain/awab206. PMID: 34037727
Fattal-Valevski A, Ben Sira L, Lerman-Sagie T, Strausberg R, Bloch-Mimouni A, Edvardson S, Kaufman R, Chernuha V, Schneebaum Sender N, Heimer G, Ben Zeev B
Eur J Paediatr Neurol 2021 May;32:40-45. Epub 2021 Mar 5 doi: 10.1016/j.ejpn.2020.08.011. PMID: 33756211
Giacomini T, Nuovo S, Zanni G, Mancardi MM, Cusmai R, Pepi C, Bertini E, Valente EM, Battini R, Ferrari A, Romaniello R, Zucca C, Borgatti R, Uccella S, Severino M, Striano P, Pistorio A, Prato G, De Grandis E, Nobili L, Pisciotta L
Eur J Paediatr Neurol 2021 Mar;31:61-69. Epub 2021 Feb 19 doi: 10.1016/j.ejpn.2021.02.006. PMID: 33640666
Ferretti A, Barresi S, Trivisano M, Ciolfi A, Dentici ML, Radio FC, Vigevano F, Tartaglia M, Specchio N
Am J Med Genet A 2019 Aug;179(8):1631-1636. Epub 2019 May 28 doi: 10.1002/ajmg.a.61206. PMID: 31136090

Therapy

Borlot F, Abushama A, Morrison-Levy N, Jain P, Puthenveettil Vinayan K, Abukhalid M, Aldhalaan HM, Almuzaini HS, Gulati S, Hershkovitz T, Konanki R, Lingappa L, Luat AF, Shafi S, Tabarki B, Thomas M, Yoganathan S, Alfadhel M, Arya R, Donner EJ, Ehaideb SN, Gowda VK, Jain V, Madaan P, Myers KA, Otsubo H, Panda P, Sahu JK, Sampaio LPB, Sharma S, Simard-Tremblay E, Zak M, Whitney R
Epilepsia 2020 Apr;61(4):679-692. Epub 2020 Mar 13 doi: 10.1111/epi.16480. PMID: 32167590
Fichera M, Failla P, Saccuzzo L, Miceli M, Salvo E, Castiglia L, Galesi O, Grillo L, Calì F, Greco D, Amato C, Romano C, Elia M
Hum Genet 2019 Feb;138(2):187-198. Epub 2019 Jan 17 doi: 10.1007/s00439-019-01972-3. PMID: 30656450
Motobayashi M, Nishimura-Tadaki A, Inaba Y, Kosho T, Miyatake S, Niimi T, Nishimura T, Wakui K, Fukushima Y, Matsumoto N, Koike K
Am J Med Genet A 2012 Apr;158A(4):861-8. Epub 2012 Mar 9 doi: 10.1002/ajmg.a.35235. PMID: 22407754
Singhi P, Ray M
Brain Dev 2005 Mar;27(2):135-40. doi: 10.1016/j.braindev.2003.10.007. PMID: 15668054

Prognosis

Rafiullah R, Albalawi AM, Alaradi SR, Alluqmani M, Mushtaq M, Wali A, Basit S
J Neurogenet 2022 Sep-Dec;36(4):108-114. Epub 2022 Dec 12 doi: 10.1080/01677063.2022.2149748. PMID: 36508181
Giacomini T, Nuovo S, Zanni G, Mancardi MM, Cusmai R, Pepi C, Bertini E, Valente EM, Battini R, Ferrari A, Romaniello R, Zucca C, Borgatti R, Uccella S, Severino M, Striano P, Pistorio A, Prato G, De Grandis E, Nobili L, Pisciotta L
Eur J Paediatr Neurol 2021 Mar;31:61-69. Epub 2021 Feb 19 doi: 10.1016/j.ejpn.2021.02.006. PMID: 33640666
Alharby E, Faqeih EA, Saleh M, Alameer S, Almuntashri M, Pastore A, Samman MA, Alnawfal AM, Hashem M, Zaytuni D, Alharbi G, Almannai M, Alasmari A, Mahmoud AA, Alwadei AH, Jad L, AlOtaibi A, Al-Hakami F, Eyaid W, Alkuraya FS, Alfadhel M, Peake RWA, Almontashiri NAM
Genet Med 2020 Dec;22(12):2071-2080. Epub 2020 Aug 3 doi: 10.1038/s41436-020-0919-x. PMID: 32741967
Bend R, Cohen L, Carter MT, Lyons MJ, Niyazov D, Mikati MA, Rojas SK, Person RE, Si Y, Wentzensen IM; Regeneron Genetics Center, Torti E, Lee JA, Boycott KM, Basel-Salmon L, Ferreira CR, Gonzaga-Jauregui C
Eur J Hum Genet 2020 Jan;28(1):76-87. Epub 2019 Aug 8 doi: 10.1038/s41431-019-0487-1. PMID: 31395947Free PMC Article
Meuwissen ME, Mancini GM
Eur J Med Genet 2012 May;55(5):323-31. Epub 2012 May 4 doi: 10.1016/j.ejmg.2012.04.007. PMID: 22564885

Clinical prediction guides

Werren EA, Srinivasan VM, Gowda VK, Pandey A, Vaish S, Kabbur AR, Nandeesh BN, Srivastava A
Am J Med Genet A 2023 Sep;191(9):2446-2450. Epub 2023 Jun 20 doi: 10.1002/ajmg.a.63310. PMID: 37337918
Chang MC, Staklinski SJ, Malut VR, Pierre GL, Kilberg MS, Merritt ME
Nutrients 2023 Apr 18;15(8) doi: 10.3390/nu15081938. PMID: 37111157Free PMC Article
Ivanov I, Pacheva I, Yordanova R, Sotkova I, Galabova F, Gaberova K, Panova M, Gheneva I, Tsvetanova T, Noneva K, Dimitrova D, Markov S, Sapundzhiev N, Bichev S, Savov A
CNS Neurol Disord Drug Targets 2023;22(2):207-214. doi: 10.2174/1871527321666220221100704. PMID: 35189806
Almannai M, Marafi D, Abdel-Salam GMH, Zaki MS, Duan R, Calame D, Herman I, Levesque F, Elbendary HM, Hegazy I, Chung WK, Kavus H, Saeidi K, Maroofian R, AlHashim A, Al-Otaibi A, Al Madhi A, Abou Al-Seood HM, Alasmari A, Houlden H, Gleeson JG, Hunter JV, Posey JE, Lupski JR, El-Hattab AW
Clin Genet 2022 May;101(5-6):530-540. Epub 2022 Apr 12 doi: 10.1111/cge.14132. PMID: 35322404Free PMC Article
Majethia P, Do Rosario MC, Kaur P, Karanvir, Shankar R, Sharma S, Siddiqui S, Shukla A
Ann Hum Genet 2022 Mar;86(2):94-101. Epub 2021 Dec 8 doi: 10.1111/ahg.12452. PMID: 34878169Free PMC Article

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