ORPHA:363549
Acute encephalopathy with biphasic seizures and late reduced diffusion
Also known as: AESD · AIEF · Acute infantile encephalopathy predominantly affecting the frontal lobes
Publications
250
65.9th percentile
Trials
0
Interventional, condition-specific
Researchers
957
Distinct authors in sample
Gene link
—
Readiness
2/6
Stages with a signal
Clinical definition (Orphanet)
A rare childhood-onset syndrome associated with infection and characterized by a biphasic clinical course. The initial symptom is a prolonged febrile seizure on day 1 (the first phase). Afterwards, patients have variable levels of consciousness from normal to coma. Irrespective of the consciousness levels, magnetic resonance imaging (MRI) during the first 2 days shows no abnormality. During the second phase (usually days 4 - 6), patients show a cluster of and deterioration of consciousness. Diffusion-weighted images (DWI) on MRI reveal the brain lesions with reduced diffusion predominantly in the subcortical white matter. After the second acute phase, consciousness levels improve with the emerging focal neurological signs. Neurological outcomes of AESD vary from normal to mild or severe sequelae including cerebral atrophy, mental retardation, paralysis and .
How rare: <1 / 1 000 000 — fewer than one in a million. In a city the size of Kolkata, that might mean on the order of fifteen people.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0018198
- UMLS:C4707658
Additional Mondo synonyms (1)
acute infantile encephalopathy predominantly affecting the frontal lobes
Research stages
Trial readiness signals
Where this condition sits on an open-data research pipeline — not how close a treatment is, and not medical advice. Empty stages often mean “not in these databases under this Mondo ID,” not “impossible.”
2/6 stages with a signal
Research-stage checklist from open sources (GenCC, literature, Monarch when enriched, ClinicalTrials.gov). Not a prognosis or care recommendation.
- Gene identifiedNot found
No GenCC disease–gene assertion in this build
- LiteraturePresent
250 matched papers (176 in last 10 years) Source
- Phenotype characterisedPresent
11 HPO annotations (e.g. Takotsubo cardiomyopathy; Bilateral tonic-clonic seizure; Hypointensity of cerebral white matter on MRI) Source
- Animal modelNot found
No Alliance genotype “model of” associations via Monarch for these Mondo IDs
- Orphan designationNot found
No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source
- Interventional trialNot found
No matched interventional trial under our ClinicalTrials.gov rules
Biology
Genes and phenotypes
Gene–disease validity from GenCC, plus phenotypes and animal models joined from Monarch Initiative via Mondo ID — not a clinical diagnosis aid.
Do we know what causes it?
Not yet — the cause hasn't been pinned down in GenCC.
No strong gene–disease assertion joined for this Orphanet entity.
Phenotypes (Monarch / HPO)
11
Associated phenotypes · MONDO:0018198
- Takotsubo cardiomyopathy
- Bilateral tonic-clonic seizure
- Hypointensity of cerebral white matter on MRI
- Complex febrile seizure
- Abnormal metabolic brain imaging by MRS
Showing 5 of 11 — open Monarch for the full list.
Animal models (Monarch / Alliance)
None returned for this Mondo ID. Empty here is not proof that no model organism work exists under another name or gene.
Monarch fetch 2026-07-29
Therapies
Designations, candidates, and chemicals
FDA OOPD and EMA orphan designations, Open Targets clinical candidates, and CTD chemical associations via MyDisease.info. These never change the interventional-trial headline.
Orphan designation (FDA · EMA)
No designation matched this disease via UMLS or preferred name on the FDA OOPD mirror or EMA orphan register. Absence here is not proof that none exists under another wording.
Open Targets candidates
No drugs or clinical candidates returned for this Mondo ID on Open Targets.
CTD chemicals (MyDisease.info)
No CTD chemical associations returned for this Mondo ID.
Literature
Is anyone studying this?
250
250 papers have ever been published on this condition (under this name). For scale, breast cancer has over 700,000. Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.
250 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 59 (publications denominator n=3967).
176 in the last 10 years · medium confidence · 65.9th percentile (publications denominator)
Phrase hits: 250 · MeSH hits: 0
Who's working on it?
957
Distinct author names in 200 sampled papers — named people below.
Who's working on it?
No interventional trial matched this name; these authors publish on it in the sampled literature — a practical starting point for contact.
- 01Takanashi JI23 papers · 2026
Department of Pediatrics, Tokyo Women's Medical University Yachiyo Medical Center, Yachiyo, Japan. Electronic address: jtaka@twmu.ac.jp.
Papers in Europe PMC - 02Nagase H17 papers · 2025
Department of Neurology, Hyogo Prefectural Kobe Children's Hospital, Japan. Electronic address: nagasehiroaki@msn.com.
Papers in Europe PMC - 03Maegaki Y16 papers · 2026
Division of Child Neurology, Faculty of Medicine, Tottori University, Japan.
Papers in Europe PMC - 04Mizuguchi M16 papers · 2025
Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Papers in Europe PMC - 05Okumura A14 papers · 2025
Department of Pediatrics, Aichi Medical University, Japan.
Papers in Europe PMC - 06Yamaguchi H14 papers · 2026
Department of Emergency and Critical Care Medicine, Hyogo Prefectural Kobe Children's Hospital, 1-1-1 Takakuradai, Suma-Ku, Kobe, Hyogo 654-0081, Japan.
Papers in Europe PMC - 07Maruyama A13 papers · 2025
Department of Neurology, Hyogo Prefectural Kobe Children's Hospital, Japan.
Papers in Europe PMC - 08Nishiyama M12 papers · 2025
Department of Neurology, Hyogo Prefectural Kobe Children's Hospital, Japan.
Papers in Europe PMC - 09Tokumoto S11 papers · 2025
Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan.
Papers in Europe PMC - 10Hoshino A10 papers · 2025
Department of Developmental Medical Sciences, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
0
interventional trials for this specific condition
No interventional trial testing a treatment matched this specific condition name on ClinicalTrials.gov (observational studies and pan-disease registries are listed separately when present).
Data as of 11 September 2026 · last trial check 11 September 2026
No matched interventional trials. This is true for 77.2% of diseases in the trials denominator (5501 of 7126). Here are the researchers publishing on it.
medium confidence · 38.6th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
No interventional trial testing a treatment was found for this specific condition name on ClinicalTrials.gov.
See who's working on it — people publishing on this disease are often the practical next contact when no trial is listed.
Other registries (secondary)
Broader net from EU CTIS, ISRCTN, and ICTRP when available — deduped against ClinicalTrials.gov IDs already counted above. Dual-model LLM relevance gates what we keep. These rows are not added to the interventional headline.
raw 0 · after dedupe 0 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 0 · dropped 0 · fetched 2026-07-30
Source notes: ictrp: Error: ICTRP public search unavailable (WHO portal is SPA-only; SOAP needs partnership). Tried: https://apps.who.int/tri
No secondary-registry studies passed dual-model relevance for this condition name (after dedupe).
Where to find support
Condition-specific patient organisations, when Orphanet lists them, are on the disease’s Orphanet page. We also link umbrella groups that support undiagnosed and ultra-rare families.
Orphanet entry for Acute encephalopathy with biphasic seizures and late reduced diffusion — check Associations / patient organisations on that page.
India — NPRD
Last verified 2026-07-26This ORPHAcode is not on our curated NPRD list (direct or Mondo-parent match). That does not decide clinical eligibility; families in India should ask a notified Centre of Excellence about current coverage.
Hand-curated for this project. ORPHAcode mappings are best-effort and may be incomplete or imprecise for umbrella categories. Parent (Mondo) matches mean the policy lists a broader category — confirm eligibility with a Centre of Excellence. Financial entitlements summarised from public policy statements and may change. This is not official government guidance.
How we counted this
Europe PMC query (preferred label + any corrected label + Orphanet and Mondo exact synonyms, stoplisted; unioned with resolved MeSH labels when available). UMLS / OMIM / NCIT cross-references are stored on the overview but are not added to the query string.
"Acute encephalopathy with biphasic seizures and late reduced diffusion" OR "Acute infantile encephalopathy predominantly affecting the frontal lobes"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Acute encephalopathy with biphasic seizures and late reduced diffusion" OR "Acute infantile encephalopathy predominantly affecting the frontal lobes"
Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: ok — strategies attempted: phrase; with hits: phrase
Run this search on ClinicalTrials.gov
Synonyms dropped by stoplist: AESD; AIEF
Confidence reasoning
- Preferred label is multi-word and distinctive
- 2 synonym(s) dropped by stoplist (may under-count)
- No label/synonym collisions with other diseases in this corpus
Ingested 2026-07-27T14:38:49.156Z