Nervous and sensory conditions

Dystonia

Dystonia, also known as dystonic disorders or distonia, is a movement disorder causing repetitive abnormal postures and movements, the third most common movement disorder after Parkinson's disease and essential tremor.

Dystonia 16

Dystonia 16, formally DYT-PRKRA, is a rare autosomal recessive dystonia caused by PRKRA gene variants, beginning in childhood, often in a limb, with prominent laryngeal involvement.

Dystonia 28

Dystonia 28 (DYT28, DYT-KMT2B) is a rare autosomal dominant dystonia caused by heterozygous KMT2B variants or 19q13.12 deletions, starting in childhood with lower-limb dystonia that generalizes, with developmental delay and response to anticholinergics and GPi DBS.

Dystonia-plus

Dystonia-plus is a category of movement disorders in which dystonia occurs with other neurological features such as myoclonus or parkinsonism, without neurodegeneration; its three main syndromes are dopa-responsive dystonia, myoclonus-dystonia, and rapid-onset dystonia-parkinsonism.

E. Antonio Chiocca

E. Antonio Chiocca, known as Nino Chiocca, is an Italian-born American neurosurgeon who chairs neurosurgery at Mass General Brigham and develops oncolytic virus therapy and immunotherapy for glioblastoma.

Eagle syndrome

Eagle syndrome, also called stylohyoid syndrome, is a neurovascular compression syndrome in which an elongated styloid process or calcified ligament causes face, throat, and neck pain.

Early infantile developmental and epileptic encephalopathy

Early infantile developmental and epileptic encephalopathy (EIDEE), formerly Ohtahara syndrome and early myoclonic encephalopathy, is a severe epilepsy syndrome with drug-resistant tonic or myoclonic seizures, burst-suppression EEG, and onset from birth to 3 months.

Early-onset autosomal dominant Alzheimer disease

Early-onset autosomal dominant Alzheimer disease (EOAD, EOFAD, ADAD): rare inherited Alzheimer disease with onset usually before 60, caused by fully penetrant PSEN1, APP, or PSEN2 mutations; under 1% of all AD cases.

Early-onset calcifying leukoencephalopathy-skeletal dysplasia

Early-onset calcifying leukoencephalopathy-skeletal dysplasia, also called BANDDOS (OMIM 618476), is an ultra-rare autosomal recessive CSF1R-related disorder combining calcifying leukoencephalopathy, brain malformations, neurodegeneration, and dysosteosclerosis-Pyle spectrum skeletal dysplasia.

Early-onset dementia

Early-onset (young-onset) dementia, YOD, is dementia with symptom onset before age 65, about 5-8% of cases, Alzheimer's disease only 34%, with long diagnostic delays and frequent psychiatric misdiagnosis.

Early-onset generalized limb-onset dystonia

Early-onset generalized limb-onset dystonia, also DYT1 or DYT-TOR1A or Oppenheim dystonia, a rare autosomal dominant dystonia from the TOR1A c.907_909delGAG deletion, starting in a limb in childhood and generalizing in 60-70% of cases.

Early-onset parkinsonism-intellectual disability syndrome

Early-onset parkinsonism-intellectual disability syndrome, or Waisman syndrome (OMIM 311510), is a rare X-linked recessive RAB39B-related disorder with infantile intellectual disability, macrocephaly, and parkinsonism before age 45, mainly in males.

Early-onset spastic ataxia-myoclonic epilepsy-neuropathy syndrome

Early-onset spastic ataxia-myoclonic epilepsy-neuropathy syndrome, also called SPAX5 or autosomal recessive spastic ataxia type 5 (OMIM 614487), is a rare biallelic AFG3L2 mitochondrial m-AAA protease disorder causing childhood spastic ataxia, neuropathy, and myoclonic epilepsy.

Early-onset X-linked optic atrophy

Early-onset X-linked optic atrophy, or optic atrophy type 2 (OPA2), is a rare X-linked recessive disorder in which boys develop progressive vision loss beginning in early childhood.

EAST syndrome

EAST syndrome, also called SeSAME syndrome, is a rare autosomal recessive KCNJ10 (Kir4.1) channelopathy causing infantile epilepsy, ataxia, sensorineural deafness, and renal salt-wasting tubulopathy with hypokalemia and hypomagnesemia.

Eating reflex epilepsy

Eating reflex epilepsy (eating epilepsy, ORPHA:166418) is a rare reflex epilepsy in which seizures are triggered by eating, chewing, or food-related stimuli. Onset typically in the second decade, male predominance, focal impaired-awareness seizures, temporolimbic or perisylvian onset.

Echolalia

Echolalia, the immediate or delayed repetition of others' speech, is common in autism (estimates 25–91%), appears in typical early language development, and occurs in aphasia, Tourette syndrome, schizophrenia, and other conditions; increasingly viewed as communicative.

Echothiophate

Echothiophate iodide (Phospholine Iodide), an irreversible organophosphate acetylcholinesterase inhibitor eye drop, lowers intraocular pressure in open-angle and aphakic glaucoma and treats accommodative esotropia; long-acting, scarce supply.

Ecstatic seizures

Ecstatic seizures are rare focal epilepsy auras of bliss, physical well-being, and heightened self-awareness with preserved consciousness. About 50-52 cases reported; linked to the dorsal anterior insula; first described by Dostoevsky.

EDICT syndrome

EDICT syndrome, an acronym for its main features, is a rare autosomal dominant eye disorder caused by a microRNA mutation, producing congenital cataracts, corneal thinning, and iris hypoplasia.

Embryonal tumor with multilayered rosettes

Embryonal tumor with multilayered rosettes (ETMR), formerly ETANTR, ependymoblastoma, or medulloepithelioma, is a WHO grade IV infant brain tumor defined by C19MC amplification (~90%), TTYH1-C19MC fusion, LIN28A expression, or rare DICER1 mutations, with survival below 30% at 5 years.

Encephalitis

Encephalitis, also called acute encephalitis syndrome, is inflammation of the brain, a serious condition caused by brain infection or autoimmune attack, producing altered consciousness, seizures, and focal neurological deficits.

Encephalitis lethargica

Encephalitis lethargica, or von Economo's disease, is a brain inflammation first described in Vienna in 1917 that caused a worldwide epidemic from about 1916 to 1927, leaving somnolence, ophthalmoplegia, and postencephalitic parkinsonism; its cause remains unknown.

Encephalocraniocutaneous lipomatosis

Encephalocraniocutaneous lipomatosis (ECCL, Haberland syndrome) is a rare sporadic mosaic RASopathy caused by postzygotic FGFR1 or KRAS variants, featuring nevus psiloliparus, ocular choristomas, CNS lipomas, seizures, and low-grade glioma risk.

Encephalopathy

Encephalopathy, also called acute or metabolic encephalopathy, is diffuse brain dysfunction from systemic causes such as sepsis, organ failure, toxins, or metabolic derangement; delirium is its clinical phenotype, and coma its severe end.

Enhanced physiological tremor

Enhanced physiological tremor (EPT), enhanced physiologic tremor, ICD-11 8A04.0: a visible, low-amplitude, high-frequency (8-12 Hz) bilateral action tremor caused by reversible amplification of normal physiological tremor by anxiety, caffeine, drugs, or hyperthyroidism, distinct from essential tremor.

Enlarged blind spot

Enlarged blind spot (cecocal scotoma), ICD-11 9D42.20: pathologic widening of the eye's normal optic-disc blind spot. Main causes are idiopathic intracranial hypertension, optic disc drusen, high myopia, and acute idiopathic blind spot enlargement syndrome.

Enteroviral meningitis

Enteroviral meningitis is viral meningitis caused by non-polio enteroviruses, the leading identified cause of viral meningitis. EV-B species, especially echovirus 30, dominate outbreaks, which peak in summer, mainly affect children, and are confirmed by CSF PCR.

Epilepsy

Epilepsy, a chronic noncommunicable brain disorder also called a seizure disorder, is defined by recurrent unprovoked seizures. About 50 million people are affected worldwide; up to 70% could become seizure-free with antiseizure medicines, and surgery helps drug-resistant focal cases.