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Developmental and epileptic encephalopathy, 26(DEE26)

MedGen UID:
863556
Concept ID:
C4015119
Disease or Syndrome
Synonyms: DEE26; Epileptic encephalopathy, early infantile, 26
 
Gene (location): KCNB1 (20q13.13)
 
Monarch Initiative: MONDO:0014477
OMIM®: 616056

Definition

Developmental and epileptic encephalopathy-26 (DEE26) is a neurologic disorder characterized by onset of variable types of seizures late in infancy or in the first years of life. Affected children show developmental delay with intellectual disability, poor speech, and behavioral abnormalities. EEG shows multifocal epileptic discharges, and may show hypsarrhythmia (summary by Torkamani et al., 2014). For a general phenotypic description and a discussion of genetic heterogeneity of DEE, see 308350. [from OMIM]

Additional description

From MedlinePlus Genetics
KCNB1 encephalopathy is a condition characterized by abnormal brain function (encephalopathy), recurrent seizures (epilepsy), and developmental delay.

Most people who have KCNB1 encephalopathy have more than one type of seizure. The seizure types that can occur in people with this condition include uncontrolled muscle twitches (myoclonic seizures), uncontrolled muscle stiffness (tonic seizures), loss of consciousness with muscle rigidity and convulsions (tonic-clonic seizures), sudden episodes of weak muscle tone (atonic seizures), sudden falls (drop attacks), or partial or complete loss of consciousness (absence seizures).

Some individuals with KCNB1 encephalopathy do not develop seizures, but they do have an abnormal pattern of electrical activity in the brain called continuous spike and waves during slow-wave sleep (CSWS). This pattern occurs during sleep, specifically during deep (slow-wave) sleep.

Children with KCNB1 encephalopathy have delayed development of speech and motor skills, such as sitting, crawling, and walking. Weak muscle tone (hypotonia) in some affected individuals can contribute to this delay. Many children with the condition eventually walk independently, but some individuals require assistance. Some affected individuals can communicate verbally using simple sentences, while others never develop the skill.

About half of individuals with KCNB1 encephalopathy also have neurodevelopmental disorders, including attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). In KCNB1 encephalopathy, problems with vision, digestion, and sleep can rarely occur.  https://medlineplus.gov/genetics/condition/kcnb1-encephalopathy

Clinical features

From HPO
Focal impaired awareness seizure
MedGen UID:
543022
Concept ID:
C0270834
Disease or Syndrome
Focal impaired awareness seizure (or focal seizure with impaired or lost awareness) is a type of focal-onset seizure characterized by some degree (which may be partial) of impairment of the person's awareness of themselves or their surroundings at any point during the seizure.
Atonic seizure
MedGen UID:
78735
Concept ID:
C0270846
Disease or Syndrome
Atonic seizure is a type of motor seizure characterized by a sudden loss or diminution of muscle tone without apparent preceding myoclonic or tonic event lasting about 1 to 2 seconds, involving head, trunk, jaw, or limb musculature.
Bilateral tonic-clonic seizure
MedGen UID:
141670
Concept ID:
C0494475
Sign or Symptom
A bilateral tonic-clonic seizure is a seizure defined by a tonic (bilateral increased tone, lasting seconds to minutes) and then a clonic (bilateral sustained rhythmic jerking) phase.
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.
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.
Stereotypical hand wringing
MedGen UID:
646835
Concept ID:
C0562479
Finding
Habitual clasping and wringing of the hands in the middle of the body, similar to a hand-washing movement.
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.
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).
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.
Absent speech
MedGen UID:
340737
Concept ID:
C1854882
Finding
Complete lack of development of speech and language abilities.
Infantile spasms
MedGen UID:
854616
Concept ID:
C3887898
Disease or Syndrome
Infantile spasms represent a subset of "epileptic spasms". Infantile Spasms are epileptic spasms starting in the first year of life (infancy).
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.

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVDevelopmental and epileptic encephalopathy, 26

Professional guidelines

PubMed

Avila EK, Tobochnik S, Inati SK, Koekkoek JAF, McKhann GM, Riviello JJ, Rudà R, Schiff D, Tatum WO, Templer JW, Weller M, Wen PY
Neuro Oncol 2024 Jan 5;26(1):7-24. doi: 10.1093/neuonc/noad154. PMID: 37699031Free PMC Article
Oppermann H, Marcos-Grañeda E, Weiss LA, Gurnett CA, Jelsig AM, Vineke SH, Isidor B, Mercier S, Magnussen K, Zacher P, Hashim M, Pagnamenta AT, Race S, Srivastava S, Frazier Z, Maiwald R, Pergande M, Milani D, Rinelli M, Levy J, Krey I, Fontana P, Lonardo F, Riley S, Kretzer J, Rankin J, Reis LM, Semina EV, Reuter MS, Scherer SW, Iascone M, Weis D, Fagerberg CR, Brasch-Andersen C, Hansen LK, Kuechler A, Noble N, Gardham A, Tenney J, Rathore G, Beck-Woedl S, Haack TB, Pavlidou DC, Atallah I, Vodopiutz J, Janecke AR, Hsieh TC, Lesmann H, Klinkhammer H, Krawitz PM, Lemke JR, Jamra RA, Nieto M, Tümer Z, Platzer K
Eur J Hum Genet 2023 Nov;31(11):1251-1260. Epub 2023 Aug 30 doi: 10.1038/s41431-023-01445-2. PMID: 37644171Free PMC Article
Pop-Jordanova N
Pril (Makedon Akad Nauk Umet Odd Med Nauki) 2019 May 1;40(1):5-40. doi: 10.2478/prilozi-2019-0001. PMID: 31152643

Recent clinical studies

Etiology

Dreier JW, Bjørk MH, Alvestad S, Gissler M, Igland J, Leinonen MK, Sun Y, Zoega H, Cohen JM, Furu K, Tomson T, Christensen J
JAMA Neurol 2023 Jun 1;80(6):568-577. doi: 10.1001/jamaneurol.2023.0674. PMID: 37067807Free 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
Knupp KG, Scheffer IE, Ceulemans B, Sullivan JE, Nickels KC, Lagae L, Guerrini R, Zuberi SM, Nabbout R, Riney K, Shore S, Agarwal A, Lock M, Farfel GM, Galer BS, Gammaitoni AR, Davis R, Gil-Nagel A
JAMA Neurol 2022 Jun 1;79(6):554-564. doi: 10.1001/jamaneurol.2022.0829. PMID: 35499850Free PMC Article
Rochtus A, Olson HE, Smith L, Keith LG, El Achkar C, Taylor A, Mahida S, Park M, Kelly M, Shain C, Rockowitz S, Rosen Sheidley B, Poduri A
Epilepsia 2020 Feb;61(2):249-258. Epub 2020 Jan 19 doi: 10.1111/epi.16427. PMID: 31957018Free PMC Article
Cox DM, Butler MG
Int J Mol Sci 2015 Feb 13;16(2):4068-82. doi: 10.3390/ijms16024068. PMID: 25689425Free PMC Article

Diagnosis

Sullivan J, Benítez A, Roth J, Andrews JS, Shah D, Butcher E, Jones A, Cross JH
Epilepsia 2024 May;65(5):1240-1263. Epub 2024 Jan 22 doi: 10.1111/epi.17866. PMID: 38252068
Avila EK, Tobochnik S, Inati SK, Koekkoek JAF, McKhann GM, Riviello JJ, Rudà R, Schiff D, Tatum WO, Templer JW, Weller M, Wen PY
Neuro Oncol 2024 Jan 5;26(1):7-24. doi: 10.1093/neuonc/noad154. PMID: 37699031Free PMC Article
Knupp KG, Scheffer IE, Ceulemans B, Sullivan JE, Nickels KC, Lagae L, Guerrini R, Zuberi SM, Nabbout R, Riney K, Shore S, Agarwal A, Lock M, Farfel GM, Galer BS, Gammaitoni AR, Davis R, Gil-Nagel A
JAMA Neurol 2022 Jun 1;79(6):554-564. doi: 10.1001/jamaneurol.2022.0829. PMID: 35499850Free PMC Article
Saleh S, Beyyumi E, Al Kaabi A, Hertecant J, Barakat D, Al Dhaheri NS, Al-Gazali L, Al Shamsi A
Clin Genet 2021 Nov;100(5):573-600. Epub 2021 Aug 19 doi: 10.1111/cge.14044. PMID: 34374989
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

Therapy

Avila EK, Tobochnik S, Inati SK, Koekkoek JAF, McKhann GM, Riviello JJ, Rudà R, Schiff D, Tatum WO, Templer JW, Weller M, Wen PY
Neuro Oncol 2024 Jan 5;26(1):7-24. doi: 10.1093/neuonc/noad154. PMID: 37699031Free PMC Article
Schoeler NE, Marston L, Lyons L, Halsall S, Jain R, Titre-Johnson S, Balogun M, Heales SJR, Eaton S, Orford M, Neal E, Reilly C, Eltze C, Stephen E, Mallick AA, O'Callaghan F, Agrawal S, Parker A, Kirkpatrick M, Brunklaus A, McLellan A, McCullagh H, Samanta R, Kneen R, Tan HJ, Devlin A, Prasad M, Rattihalli R, Basu H, Desurkar A, Williams R, Fallon P, Nazareth I, Freemantle N, Cross JH; KIWE study group
Lancet Neurol 2023 Dec;22(12):1113-1124. doi: 10.1016/S1474-4422(23)00370-8. PMID: 37977712
Dreier JW, Bjørk MH, Alvestad S, Gissler M, Igland J, Leinonen MK, Sun Y, Zoega H, Cohen JM, Furu K, Tomson T, Christensen J
JAMA Neurol 2023 Jun 1;80(6):568-577. doi: 10.1001/jamaneurol.2023.0674. PMID: 37067807Free PMC Article
Knupp KG, Scheffer IE, Ceulemans B, Sullivan JE, Nickels KC, Lagae L, Guerrini R, Zuberi SM, Nabbout R, Riney K, Shore S, Agarwal A, Lock M, Farfel GM, Galer BS, Gammaitoni AR, Davis R, Gil-Nagel A
JAMA Neurol 2022 Jun 1;79(6):554-564. doi: 10.1001/jamaneurol.2022.0829. PMID: 35499850Free PMC Article
Nickels K, Kossoff EH, Eschbach K, Joshi C
Epilepsia 2021 Jan;62(1):120-127. Epub 2020 Nov 14 doi: 10.1111/epi.16752. PMID: 33190223

Prognosis

Sullivan J, Benítez A, Roth J, Andrews JS, Shah D, Butcher E, Jones A, Cross JH
Epilepsia 2024 May;65(5):1240-1263. Epub 2024 Jan 22 doi: 10.1111/epi.17866. PMID: 38252068
Avila EK, Tobochnik S, Inati SK, Koekkoek JAF, McKhann GM, Riviello JJ, Rudà R, Schiff D, Tatum WO, Templer JW, Weller M, Wen PY
Neuro Oncol 2024 Jan 5;26(1):7-24. doi: 10.1093/neuonc/noad154. PMID: 37699031Free PMC Article
Schoeler NE, Marston L, Lyons L, Halsall S, Jain R, Titre-Johnson S, Balogun M, Heales SJR, Eaton S, Orford M, Neal E, Reilly C, Eltze C, Stephen E, Mallick AA, O'Callaghan F, Agrawal S, Parker A, Kirkpatrick M, Brunklaus A, McLellan A, McCullagh H, Samanta R, Kneen R, Tan HJ, Devlin A, Prasad M, Rattihalli R, Basu H, Desurkar A, Williams R, Fallon P, Nazareth I, Freemantle N, Cross JH; KIWE study group
Lancet Neurol 2023 Dec;22(12):1113-1124. doi: 10.1016/S1474-4422(23)00370-8. PMID: 37977712
Oppermann H, Marcos-Grañeda E, Weiss LA, Gurnett CA, Jelsig AM, Vineke SH, Isidor B, Mercier S, Magnussen K, Zacher P, Hashim M, Pagnamenta AT, Race S, Srivastava S, Frazier Z, Maiwald R, Pergande M, Milani D, Rinelli M, Levy J, Krey I, Fontana P, Lonardo F, Riley S, Kretzer J, Rankin J, Reis LM, Semina EV, Reuter MS, Scherer SW, Iascone M, Weis D, Fagerberg CR, Brasch-Andersen C, Hansen LK, Kuechler A, Noble N, Gardham A, Tenney J, Rathore G, Beck-Woedl S, Haack TB, Pavlidou DC, Atallah I, Vodopiutz J, Janecke AR, Hsieh TC, Lesmann H, Klinkhammer H, Krawitz PM, Lemke JR, Jamra RA, Nieto M, Tümer Z, Platzer K
Eur J Hum Genet 2023 Nov;31(11):1251-1260. Epub 2023 Aug 30 doi: 10.1038/s41431-023-01445-2. PMID: 37644171Free PMC Article
Dreier JW, Bjørk MH, Alvestad S, Gissler M, Igland J, Leinonen MK, Sun Y, Zoega H, Cohen JM, Furu K, Tomson T, Christensen J
JAMA Neurol 2023 Jun 1;80(6):568-577. doi: 10.1001/jamaneurol.2023.0674. PMID: 37067807Free PMC Article

Clinical prediction guides

Knupp KG, Scheffer IE, Ceulemans B, Sullivan JE, Nickels KC, Lagae L, Guerrini R, Zuberi SM, Nabbout R, Riney K, Shore S, Agarwal A, Lock M, Farfel GM, Galer BS, Gammaitoni AR, Davis R, Gil-Nagel A
JAMA Neurol 2022 Jun 1;79(6):554-564. doi: 10.1001/jamaneurol.2022.0829. PMID: 35499850Free PMC Article
Kummeling J, Stremmelaar DE, Raun N, Reijnders MRF, Willemsen MH, Ruiterkamp-Versteeg M, Schepens M, Man CCO, Gilissen C, Cho MT, McWalter K, Sinnema M, Wheless JW, Simon MEH, Genetti CA, Casey AM, Terhal PA, van der Smagt JJ, van Gassen KLI, Joset P, Bahr A, Steindl K, Rauch A, Keller E, Raas-Rothschild A, Koolen DA, Agrawal PB, Hoffman TL, Powell-Hamilton NN, Thiffault I, Engleman K, Zhou D, Bodamer O, Hoefele J, Riedhammer KM, Schwaibold EMC, Tasic V, Schubert D, Top D, Pfundt R, Higgs MR, Kramer JM, Kleefstra T
Mol Psychiatry 2021 Jun;26(6):2013-2024. Epub 2020 Apr 28 doi: 10.1038/s41380-020-0725-5. PMID: 32346159
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
Pop-Jordanova N
Pril (Makedon Akad Nauk Umet Odd Med Nauki) 2019 May 1;40(1):5-40. doi: 10.2478/prilozi-2019-0001. PMID: 31152643
Cox DM, Butler MG
Int J Mol Sci 2015 Feb 13;16(2):4068-82. doi: 10.3390/ijms16024068. PMID: 25689425Free PMC Article

Recent systematic reviews

Bayat A, Grimes H, de Boer E, Herlin MK, Dahl RS, Lund ICB, Bayat M, Bolund ACS, Gjerulfsen CE, Gregersen PA, Zilmer M, Juhl S, Cebula K, Rahikkala E, Maystadt I, Peron A, Vignoli A, Alfano RM, Stanzial F, Benedicenti F, Currò A, Luk HM, Jouret G, Zurita E, Heuft L, Schnabel F, Busche A, Veenstra-Knol HE, Tkemaladze T, Vrielynck P, Lederer D, Platzer K, Ockeloen CW, Goel H, Low KJ
Genet Med 2024 Aug;26(8):101170. Epub 2024 May 27 doi: 10.1016/j.gim.2024.101170. PMID: 38818797
Sullivan J, Benítez A, Roth J, Andrews JS, Shah D, Butcher E, Jones A, Cross JH
Epilepsia 2024 May;65(5):1240-1263. Epub 2024 Jan 22 doi: 10.1111/epi.17866. PMID: 38252068
Lattanzi S, Trinka E, Russo E, Del Giovane C, Matricardi S, Meletti S, Striano P, Damavandi PT, Silvestrini M, Brigo F
Drugs 2023 Oct;83(15):1409-1424. Epub 2023 Sep 11 doi: 10.1007/s40265-023-01936-y. PMID: 37695433Free PMC Article
El Meskine T, Li J, Reise J, Toffa DH
Epileptic Disord 2023 Apr;25(2):209-217. Epub 2023 May 3 doi: 10.1002/epd2.20020. PMID: 36992563
Frank NA, Greuter L, Guzman R, Soleman J
Childs Nerv Syst 2023 Mar;39(3):677-688. Epub 2022 Oct 11 doi: 10.1007/s00381-022-05699-x. PMID: 36219224

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