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Developmental and epileptic encephalopathy, 18(DEE18)

MedGen UID:
815954
Concept ID:
C3809624
Disease or Syndrome
Synonyms: DEE18; Early infantile epileptic encephalopathy 18
 
Gene (location): SZT2 (1p34.2)
 
Monarch Initiative: MONDO:0014201
OMIM®: 615476

Definition

Developmental and epileptic encephalopathy-18 (DEE18) is a severe autosomal recessive neurologic disorder characterized by lack of psychomotor development apparent from birth, dysmorphic facial features, and early onset of refractory seizures. Brain imaging shows a thick corpus callosum and persistent cavum septum pellucidum on brain imaging (summary by Basel-Vanagaite et al., 2013). For a general phenotypic description and a discussion of genetic heterogeneity of DEE, see 308350. [from OMIM]

Clinical features

From HPO
Aortic regurgitation
MedGen UID:
8153
Concept ID:
C0003504
Disease or Syndrome
An insufficiency of the aortic valve, leading to regurgitation (backward flow) of blood from the aorta into the left ventricle.
Atrial septal defect
MedGen UID:
6753
Concept ID:
C0018817
Congenital Abnormality
Atrial septal defect (ASD) is a congenital abnormality of the interatrial septum that enables blood flow between the left and right atria via the interatrial septum.
EEG abnormality
MedGen UID:
56235
Concept ID:
C0151611
Finding
Abnormality observed by electroencephalogram (EEG), which is used to record of the brain's spontaneous electrical activity from multiple electrodes placed on the scalp.
Generalized-onset seizure
MedGen UID:
115963
Concept ID:
C0234533
Disease or Syndrome
A generalized-onset seizure is a type of seizure originating at some point within, and rapidly engaging, bilaterally distributed networks. The networks may include cortical and subcortical structures but not necessarily the entire cortex.
Tonic seizure
MedGen UID:
82855
Concept ID:
C0270844
Disease or Syndrome
A tonic seizure is a type of motor seizure characterized by unilateral or bilateral limb stiffening or elevation, often with neck stiffening.
Epileptic encephalopathy
MedGen UID:
452596
Concept ID:
C0543888
Disease or Syndrome
A condition in which epileptiform abnormalities are believed to contribute to the progressive disturbance in cerebral function. Epileptic encephalaopathy is characterized by (1) electrographic EEG paroxysmal activity that is often aggressive, (2) seizures that are usually multiform and intractable, (3) cognitive, behavioral and neurological deficits that may be relentless, and (4) sometimes early death.
Atypical absence seizure
MedGen UID:
108888
Concept ID:
C0595948
Disease or Syndrome
An atypical absence seizure is a type of generalized non-motor (absence) seizure characterized by interruption of ongoing activities and reduced responsiveness. In comparison to a typical absence seizure, changes in tone may be more pronounced, onset and/or cessation may be less abrupt, and the duration of the ictus and post-ictal recovery may be longer. Although not always available, an EEG often demonstrates slow (<3 Hz), irregular, generalized spike-wave activity.
Hyporeflexia
MedGen UID:
195967
Concept ID:
C0700078
Finding
Reduction of neurologic reflexes such as the knee-jerk reaction.
Focal-onset seizure
MedGen UID:
199670
Concept ID:
C0751495
Disease or Syndrome
A focal-onset seizure is a type of seizure originating within networks limited to one hemisphere. They may be discretely localized or more widely distributed, and may originate in subcortical structures.
Bilateral tonic-clonic seizure with focal onset
MedGen UID:
164077
Concept ID:
C0877017
Disease or Syndrome
A bilateral tonic-clonic seizure with focal onset is a focal-onset seizure which progresses into a bilateral tonic-clonic phase.
Thick corpus callosum
MedGen UID:
371993
Concept ID:
C1835194
Finding
Increased vertical dimension of the corpus callosum. This feature can be visualized by sagittal sections on magnetic resonance tomography imaging of the brain.
Absent speech
MedGen UID:
340737
Concept ID:
C1854882
Finding
Complete lack of development of speech and language abilities.
Profound global developmental delay
MedGen UID:
766364
Concept ID:
C3553450
Disease or Syndrome
A profound delay in the achievement of motor or mental milestones in the domains of development of a child.
Generalized non-motor (absence) seizure
MedGen UID:
1385688
Concept ID:
C4316903
Disease or Syndrome
A generalized non-motor (absence) seizure is a type of a type of dialeptic seizure that is of electrographically generalized onset. It is a generalized seizure characterized by an interruption of activities, a blank stare, and usually the person will be unresponsive when spoken to. Any ictal motor phenomena are minor in comparison to these non-motor features.
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.
High forehead
MedGen UID:
65991
Concept ID:
C0239676
Finding
An abnormally increased height of the forehead.
Downslanted palpebral fissures
MedGen UID:
98391
Concept ID:
C0423110
Finding
The palpebral fissure inclination is more than two standard deviations below the mean.
Highly arched eyebrow
MedGen UID:
358357
Concept ID:
C1868571
Finding
Increased height of the central portion of the eyebrow, forming a crescent, semicircular, or inverted U shape.
Polyhydramnios
MedGen UID:
6936
Concept ID:
C0020224
Pathologic Function
The presence of excess amniotic fluid in the uterus during pregnancy.
Oligohydramnios
MedGen UID:
86974
Concept ID:
C0079924
Pathologic Function
Diminished amniotic fluid volume in pregnancy.
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).

Professional guidelines

PubMed

Cohen NT, Cross JH, Arzimanoglou A, Berkovic SF, Kerrigan JF, Miller IP, Webster E, Soeby L, Cukiert A, Hesdorffer DK, Kroner BL, Saper CB, Schulze-Bonhage A, Gaillard WD; Hypothalamic Hamartoma Writing Group
Neurology 2021 Nov 2;97(18):864-873. Epub 2021 Oct 4 doi: 10.1212/WNL.0000000000012773. PMID: 34607926Free PMC Article
Le Roux M, Barth M, Gueden S, Desbordes de Cepoy P, Aeby A, Vilain C, Hirsch E, de Saint Martin A, Portes VD, Lesca G, Riquet A, Chaton L, Villeneuve N, Villard L, Cances C, Valton L, Renaldo F, Vermersch AI, Altuzarra C, Nguyen-Morel MA, Van Gils J, Angelini C, Biraben A, Arnaud L, Riant F, Van Bogaert P
Eur J Paediatr Neurol 2021 Jul;33:75-85. Epub 2021 May 26 doi: 10.1016/j.ejpn.2021.05.010. PMID: 34102571
McTague A, Martland T, Appleton R
Cochrane Database Syst Rev 2018 Jan 10;1(1):CD001905. doi: 10.1002/14651858.CD001905.pub3. PMID: 29320603Free PMC Article

Recent clinical studies

Etiology

Strzelczyk A, Zuberi SM, Striano P, Rosenow F, Schubert-Bast S
Orphanet J Rare Dis 2023 Mar 1;18(1):42. doi: 10.1186/s13023-023-02626-4. PMID: 36859290Free PMC Article
Poke G, Stanley J, Scheffer IE, Sadleir LG
Neurology 2023 Mar 28;100(13):e1363-e1375. Epub 2022 Dec 29 doi: 10.1212/WNL.0000000000206758. PMID: 36581463Free PMC Article
Bar C, Kuchenbuch M, Barcia G, Schneider A, Jennesson M, Le Guyader G, Lesca G, Mignot C, Montomoli M, Parrini E, Isnard H, Rolland A, Keren B, Afenjar A, Dorison N, Sadleir LG, Breuillard D, Levy R, Rio M, Dupont S, Negrin S, Danieli A, Scalais E, De Saint Martin A, El Chehadeh S, Chelly J, Poisson A, Lebre AS, Nica A, Odent S, Sekhara T, Brankovic V, Goldenberg A, Vrielynck P, Lederer D, Maurey H, Terrone G, Besmond C, Hubert L, Berquin P, Billette de Villemeur T, Isidor B, Freeman JL, Mefford HC, Myers CT, Howell KB, Rodríguez-Sacristán Cascajo A, Meyer P, Genevieve D, Guët A, Doummar D, Durigneux J, van Dooren MF, de Wit MCY, Gerard M, Marey I, Munnich A, Guerrini R, Scheffer IE, Kabashi E, Nabbout R
Epilepsia 2020 Nov;61(11):2461-2473. Epub 2020 Sep 21 doi: 10.1111/epi.16679. PMID: 32954514
Salpietro V, Dixon CL, Guo H, Bello OD, Vandrovcova J, Efthymiou S, Maroofian R, Heimer G, Burglen L, Valence S, Torti E, Hacke M, Rankin J, Tariq H, Colin E, Procaccio V, Striano P, Mankad K, Lieb A, Chen S, Pisani L, Bettencourt C, Männikkö R, Manole A, Brusco A, Grosso E, Ferrero GB, Armstrong-Moron J, Gueden S, Bar-Yosef O, Tzadok M, Monaghan KG, Santiago-Sim T, Person RE, Cho MT, Willaert R, Yoo Y, Chae JH, Quan Y, Wu H, Wang T, Bernier RA, Xia K, Blesson A, Jain M, Motazacker MM, Jaeger B, Schneider AL, Boysen K, Muir AM, Myers CT, Gavrilova RH, Gunderson L, Schultz-Rogers L, Klee EW, Dyment D, Osmond M, Parellada M, Llorente C, Gonzalez-Peñas J, Carracedo A, Van Haeringen A, Ruivenkamp C, Nava C, Heron D, Nardello R, Iacomino M, Minetti C, Skabar A, Fabretto A; SYNAPS Study Group, Raspall-Chaure M, Chez M, Tsai A, Fassi E, Shinawi M, Constantino JN, De Zorzi R, Fortuna S, Kok F, Keren B, Bonneau D, Choi M, Benzeev B, Zara F, Mefford HC, Scheffer IE, Clayton-Smith J, Macaya A, Rothman JE, Eichler EE, Kullmann DM, Houlden H
Nat Commun 2019 Jul 12;10(1):3094. doi: 10.1038/s41467-019-10910-w. PMID: 31300657Free PMC Article
Vlaskamp DRM, Shaw BJ, Burgess R, Mei D, Montomoli M, Xie H, Myers CT, Bennett MF, XiangWei W, Williams D, Maas SM, Brooks AS, Mancini GMS, van de Laar IMBH, van Hagen JM, Ware TL, Webster RI, Malone S, Berkovic SF, Kalnins RM, Sicca F, Korenke GC, van Ravenswaaij-Arts CMA, Hildebrand MS, Mefford HC, Jiang Y, Guerrini R, Scheffer IE
Neurology 2019 Jan 8;92(2):e96-e107. Epub 2018 Dec 12 doi: 10.1212/WNL.0000000000006729. PMID: 30541864Free PMC Article

Diagnosis

Donnan AM, Schneider AL, Russ-Hall S, Churilov L, Scheffer IE
Neurology 2023 Apr 18;100(16):e1712-e1722. Epub 2023 Feb 7 doi: 10.1212/WNL.0000000000207080. PMID: 36750385Free PMC Article
Poke G, Stanley J, Scheffer IE, Sadleir LG
Neurology 2023 Mar 28;100(13):e1363-e1375. Epub 2022 Dec 29 doi: 10.1212/WNL.0000000000206758. PMID: 36581463Free PMC Article
Slegers RJ, Blumcke I
Acta Neuropathol Commun 2020 Mar 9;8(1):27. doi: 10.1186/s40478-020-00904-x. PMID: 32151273Free PMC Article
Takata A, Nakashima M, Saitsu H, Mizuguchi T, Mitsuhashi S, Takahashi Y, Okamoto N, Osaka H, Nakamura K, Tohyama J, Haginoya K, Takeshita S, Kuki I, Okanishi T, Goto T, Sasaki M, Sakai Y, Miyake N, Miyatake S, Tsuchida N, Iwama K, Minase G, Sekiguchi F, Fujita A, Imagawa E, Koshimizu E, Uchiyama Y, Hamanaka K, Ohba C, Itai T, Aoi H, Saida K, Sakaguchi T, Den K, Takahashi R, Ikeda H, Yamaguchi T, Tsukamoto K, Yoshitomi S, Oboshi T, Imai K, Kimizu T, Kobayashi Y, Kubota M, Kashii H, Baba S, Iai M, Kira R, Hara M, Ohta M, Miyata Y, Miyata R, Takanashi JI, Matsui J, Yokochi K, Shimono M, Amamoto M, Takayama R, Hirabayashi S, Aiba K, Matsumoto H, Nabatame S, Shiihara T, Kato M, Matsumoto N
Nat Commun 2019 Jun 7;10(1):2506. doi: 10.1038/s41467-019-10482-9. PMID: 31175295Free PMC Article
Koch H, Weber YG
Epilepsy Behav 2019 Feb;91:90-93. Epub 2018 Jul 31 doi: 10.1016/j.yebeh.2018.06.010. PMID: 30076047

Therapy

Elkommos S, Mula M
Expert Opin Pharmacother 2022 Dec;23(18):2023-2034. Epub 2022 Sep 27 doi: 10.1080/14656566.2022.2128670. PMID: 36154780
Hahn CD, Jiang Y, Villanueva V, Zolnowska M, Arkilo D, Hsiao S, Asgharnejad M, Dlugos D
Epilepsia 2022 Oct;63(10):2671-2683. Epub 2022 Aug 4 doi: 10.1111/epi.17367. PMID: 35841234Free PMC Article
Vazquez B, Tomson T, Dobrinsky C, Schuck E, O'Brien TJ
Epilepsia 2021 Mar;62(3):698-708. doi: 10.1111/epi.16821. PMID: 33666943Free PMC Article
Vlaskamp DRM, Shaw BJ, Burgess R, Mei D, Montomoli M, Xie H, Myers CT, Bennett MF, XiangWei W, Williams D, Maas SM, Brooks AS, Mancini GMS, van de Laar IMBH, van Hagen JM, Ware TL, Webster RI, Malone S, Berkovic SF, Kalnins RM, Sicca F, Korenke GC, van Ravenswaaij-Arts CMA, Hildebrand MS, Mefford HC, Jiang Y, Guerrini R, Scheffer IE
Neurology 2019 Jan 8;92(2):e96-e107. Epub 2018 Dec 12 doi: 10.1212/WNL.0000000000006729. PMID: 30541864Free PMC Article
Veroniki AA, Rios P, Cogo E, Straus SE, Finkelstein Y, Kealey R, Reynen E, Soobiah C, Thavorn K, Hutton B, Hemmelgarn BR, Yazdi F, D'Souza J, MacDonald H, Tricco AC
BMJ Open 2017 Jul 20;7(7):e017248. doi: 10.1136/bmjopen-2017-017248. PMID: 28729328Free PMC Article

Prognosis

van Hugte EJH, Lewerissa EI, Wu KM, Scheefhals N, Parodi G, van Voorst TW, Puvogel S, Kogo N, Keller JM, Frega M, Schubert D, Schelhaas HJ, Verhoeven J, Majoie M, van Bokhoven H, Nadif Kasri N
Brain 2023 Dec 1;146(12):5153-5167. doi: 10.1093/brain/awad245. PMID: 37467479Free PMC Article
Hamanaka K, Miyake N, Mizuguchi T, Miyatake S, Uchiyama Y, Tsuchida N, Sekiguchi F, Mitsuhashi S, Tsurusaki Y, Nakashima M, Saitsu H, Yamada K, Sakamoto M, Fukuda H, Ohori S, Saida K, Itai T, Azuma Y, Koshimizu E, Fujita A, Erturk B, Hiraki Y, Ch'ng GS, Kato M, Okamoto N, Takata A, Matsumoto N
Genome Med 2022 Apr 26;14(1):40. doi: 10.1186/s13073-022-01042-w. PMID: 35468861Free PMC Article
Vazquez B, Tomson T, Dobrinsky C, Schuck E, O'Brien TJ
Epilepsia 2021 Mar;62(3):698-708. doi: 10.1111/epi.16821. PMID: 33666943Free PMC Article
Bar C, Kuchenbuch M, Barcia G, Schneider A, Jennesson M, Le Guyader G, Lesca G, Mignot C, Montomoli M, Parrini E, Isnard H, Rolland A, Keren B, Afenjar A, Dorison N, Sadleir LG, Breuillard D, Levy R, Rio M, Dupont S, Negrin S, Danieli A, Scalais E, De Saint Martin A, El Chehadeh S, Chelly J, Poisson A, Lebre AS, Nica A, Odent S, Sekhara T, Brankovic V, Goldenberg A, Vrielynck P, Lederer D, Maurey H, Terrone G, Besmond C, Hubert L, Berquin P, Billette de Villemeur T, Isidor B, Freeman JL, Mefford HC, Myers CT, Howell KB, Rodríguez-Sacristán Cascajo A, Meyer P, Genevieve D, Guët A, Doummar D, Durigneux J, van Dooren MF, de Wit MCY, Gerard M, Marey I, Munnich A, Guerrini R, Scheffer IE, Kabashi E, Nabbout R
Epilepsia 2020 Nov;61(11):2461-2473. Epub 2020 Sep 21 doi: 10.1111/epi.16679. PMID: 32954514
Bar C, Barcia G, Jennesson M, Le Guyader G, Schneider A, Mignot C, Lesca G, Breuillard D, Montomoli M, Keren B, Doummar D, Billette de Villemeur T, Afenjar A, Marey I, Gerard M, Isnard H, Poisson A, Dupont S, Berquin P, Meyer P, Genevieve D, De Saint Martin A, El Chehadeh S, Chelly J, Guët A, Scalais E, Dorison N, Myers CT, Mefford HC, Howell KB, Marini C, Freeman JL, Nica A, Terrone G, Sekhara T, Lebre AS, Odent S, Sadleir LG, Munnich A, Guerrini R, Scheffer IE, Kabashi E, Nabbout R
Hum Mutat 2020 Jan;41(1):69-80. Epub 2019 Oct 4 doi: 10.1002/humu.23915. PMID: 31513310

Clinical prediction guides

van Hugte EJH, Lewerissa EI, Wu KM, Scheefhals N, Parodi G, van Voorst TW, Puvogel S, Kogo N, Keller JM, Frega M, Schubert D, Schelhaas HJ, Verhoeven J, Majoie M, van Bokhoven H, Nadif Kasri N
Brain 2023 Dec 1;146(12):5153-5167. doi: 10.1093/brain/awad245. PMID: 37467479Free PMC Article
Donnan AM, Schneider AL, Russ-Hall S, Churilov L, Scheffer IE
Neurology 2023 Apr 18;100(16):e1712-e1722. Epub 2023 Feb 7 doi: 10.1212/WNL.0000000000207080. PMID: 36750385Free PMC Article
Hahn CD, Jiang Y, Villanueva V, Zolnowska M, Arkilo D, Hsiao S, Asgharnejad M, Dlugos D
Epilepsia 2022 Oct;63(10):2671-2683. Epub 2022 Aug 4 doi: 10.1111/epi.17367. PMID: 35841234Free PMC Article
Takata A, Nakashima M, Saitsu H, Mizuguchi T, Mitsuhashi S, Takahashi Y, Okamoto N, Osaka H, Nakamura K, Tohyama J, Haginoya K, Takeshita S, Kuki I, Okanishi T, Goto T, Sasaki M, Sakai Y, Miyake N, Miyatake S, Tsuchida N, Iwama K, Minase G, Sekiguchi F, Fujita A, Imagawa E, Koshimizu E, Uchiyama Y, Hamanaka K, Ohba C, Itai T, Aoi H, Saida K, Sakaguchi T, Den K, Takahashi R, Ikeda H, Yamaguchi T, Tsukamoto K, Yoshitomi S, Oboshi T, Imai K, Kimizu T, Kobayashi Y, Kubota M, Kashii H, Baba S, Iai M, Kira R, Hara M, Ohta M, Miyata Y, Miyata R, Takanashi JI, Matsui J, Yokochi K, Shimono M, Amamoto M, Takayama R, Hirabayashi S, Aiba K, Matsumoto H, Nabatame S, Shiihara T, Kato M, Matsumoto N
Nat Commun 2019 Jun 7;10(1):2506. doi: 10.1038/s41467-019-10482-9. PMID: 31175295Free PMC Article
Franceschetti S, Canafoglia L
Epileptic Disord 2016 Sep 1;18(S2):89-93. doi: 10.1684/epd.2016.0845. PMID: 27621198

Recent systematic reviews

Stefanos-Yakoub I, Wingeier K, Held U, Latal B, Wirrell E, Smith ML, Ramantani G
Epilepsia 2024 Feb;65(2):251-265. Epub 2023 Dec 9 doi: 10.1111/epi.17834. PMID: 38031640
Strzelczyk A, Zuberi SM, Striano P, Rosenow F, Schubert-Bast S
Orphanet J Rare Dis 2023 Mar 1;18(1):42. doi: 10.1186/s13023-023-02626-4. PMID: 36859290Free PMC Article
McTague A, Martland T, Appleton R
Cochrane Database Syst Rev 2018 Jan 10;1(1):CD001905. doi: 10.1002/14651858.CD001905.pub3. PMID: 29320603Free PMC Article
Veroniki AA, Rios P, Cogo E, Straus SE, Finkelstein Y, Kealey R, Reynen E, Soobiah C, Thavorn K, Hutton B, Hemmelgarn BR, Yazdi F, D'Souza J, MacDonald H, Tricco AC
BMJ Open 2017 Jul 20;7(7):e017248. doi: 10.1136/bmjopen-2017-017248. PMID: 28729328Free PMC Article
Hancock EC, Osborne JP, Edwards SW
Cochrane Database Syst Rev 2013 Jun 5;2013(6):CD001770. doi: 10.1002/14651858.CD001770.pub3. PMID: 23740534Free PMC Article

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