1,527 articles
13q12.3 microdeletion syndrome
13q12.3 microdeletion syndrome (Del(13)(q12.3), monosomy 13q12.3) is a rare chromosomal anomaly with moderate intellectual disability, speech delay, postnatal microcephaly, atopic dermatitis, characteristic facies, and reduced pain sensitivity, attributed mainly to HMGB1 haploinsufficiency.
20q11.2 microdeletion syndrome
20q11.2 microdeletion syndrome (Del(20)(q11.2), Monosomy 20q11, ORPHA:444051) is a rare chromosomal microdeletion disorder causing syndromic intellectual disability, hypotonia, feeding difficulties, hand and foot anomalies, and craniofacial dysmorphism, with GDF5, EPB41L1, and SAMHD1 as candidate genes.
4H leukodystrophy
4H leukodystrophy, also called POLR3-related leukodystrophy, is an autosomal recessive hypomyelinating leukodystrophy caused by biallelic variants in POLR3A, POLR3B, POLR1C, or POLR3K, marked by hypomyelination, hypodontia, and hypogonadotropic hypogonadism.
A-172
A-172 (A172, CVCL_0131, ATCC CRL-1620) is a human glioblastoma cell line from a 53-year-old male, PTEN-deleted, IDH1-wildtype, MSS, adherent with epithelial-like morphology, doubling time about 26-48 hours.
Abnormal head movements
Abnormal head movements are involuntary movements of the head and neck that occur in neurological conditions such as tremor disorders, dystonia, chorea, tics, and myoclonus, and help distinguish diagnoses like cervical dystonia from essential tremor.
Abnormal involuntary movements
Abnormal involuntary movements (ICD-11 MB46) are uncontrolled, unintended movements such as tremor, myoclonus, chorea, athetosis, dystonia, and hemiballism, coded as nervous-system signs and distinguished from tic disorders and essential tremor.
Abnormal reflex (disease)
Abnormal reflex (ICD-11 MB47.0), also indexed as hyperreflexia, hyporeflexia, and areflexia, is a neurological sign of exaggerated, diminished, or absent reflexes, graded 0 to 4+, indicating reflex arc or descending pathway lesions.
Abruzzo-Erickson syndrome
Abruzzo-Erickson syndrome (ABERS, CHARGE-like syndrome) is an extremely rare X-linked recessive disorder caused by TBX22 mutations, featuring cleft palate, coloboma, hypospadias, hearing loss, short stature, and radioulnar synostosis.
Abscess of eyelid
Abscess of eyelid (ICD-11 9A01.1), a pus collection in eyelid tissue, usually staphylococcal; includes hordeolum and abscess complicating preseptal cellulitis, treated by incision and drainage plus antibiotics.
Absence seizure
Absence seizure (petit mal): a generalized-onset epileptic seizure with sudden brief loss of awareness, blank stare, and 3 Hz spike-wave EEG, occurring mainly in children 4 to 12, treated with ethosuximide or valproic acid.
Absence seizures, atypical
Atypical absence seizures are generalized absence seizures with gradual onset and offset, pronounced tone changes, and slow irregular spike-and-wave EEG activity, typically in Lennox–Gastaut syndrome.
Absence status epilepticus
Absence status epilepticus (ASE, petit mal status) is a nonconvulsive status epilepticus: a generalized absence seizure over 30 minutes to days causing confusion, with 2.5-4 Hz spike-wave EEG, treated with low-dose benzodiazepines.
Acalculia
Acalculia (ICD-11 MB4B.2) is the acquired loss of calculation ability after stroke, brain injury, or degenerative disease, distinct from developmental dyscalculia; coined by Henschen 1920, a Gerstmann syndrome symptom, classified as primary (anarithmetia) or secondary forms.
Acetazolamide-responsive myotonia
Acetazolamide-responsive myotonia, also called painful or atypical myotonia congenita, is a rare autosomal dominant SCN4A (Nav1.4) sodium channelopathy causing childhood-onset painful, potassium-triggered myotonia without weakness, dramatically improved by acetazolamide.
Acoustic neuritis
Acoustic neuritis (auditory nerve neuritis, ICD-11 AB72.0) is inflammation of the eighth cranial nerve; vestibular-branch disease causes vertigo without hearing loss, cochlear-branch disease tinnitus and deafness.
Acquired conductive hearing loss
Acquired conductive hearing loss (ICD-11 AB51.0) is hearing loss developing after birth from mechanical outer- or middle-ear problems such as cerumen, otitis media, perforation, or otosclerosis, showing an air-bone gap and often correctable.
Acquired hearing impairment
Acquired hearing impairment (ICD-11 AB51) is hearing loss arising after language acquisition, not present at birth, from disease, trauma, or medicines. Covers conductive, sensorineural, and mixed types, causes, prevalence, screening, and rehabilitation.
Acquired optic atrophy
Acquired optic atrophy, ICD-11 9C40.B1, is postnatal death of retinal ganglion cell axons causing a pale optic disc and vision loss, from glaucoma, ischemia, compression, inflammation, infection, toxins, or trauma.
Acquired sensorineural hearing loss
Acquired sensorineural hearing loss (ICD-11 AB51.1) is postnatal hearing loss from inner ear, vestibulocochlear nerve, or central causes; main forms are age-related, noise-induced, drug-induced, and sudden SNHL, treated with hearing aids or cochlear implants.
Acrania
Acrania: congenital absence of the fetal cranial vault and overlying skin with exposed brain tissue; first stage of the acrania–exencephaly–anencephaly sequence, lethal, detectable by ultrasound from about 11 weeks.
Acroparaesthesia
Acroparaesthesia (acroparesthesia) is tingling, numbness, or burning in the hands and feet, especially fingers and toes. A symptom rather than a disease, most often caused by carpal tunnel syndrome; named in 1890, historically linked to Schultze.
Action myoclonus-renal failure syndrome
Action myoclonus-renal failure syndrome (AMRF, EPM4, OMIM 254900) is a rare autosomal recessive progressive myoclonic epilepsy with proteinuria and kidney failure, caused by biallelic SCARB2/LIMP-2 loss-of-function mutations, onset in teens or twenties, death within 7-15 years.
Acute annular outer retinopathy
Acute annular outer retinopathy (AAOR) is a rare unilateral outer retinal disorder, a 1995 Gass and Stern variant of AZOOR, marked by acute visual field loss and a peripapillary gray-white intraretinal ring, with possible spontaneous recovery.
Acute bilirubin encephalopathy
Acute bilirubin encephalopathy (ABE), also called bilirubin-induced neurologic dysfunction, is acute neonatal brain injury from unbound unconjugated bilirubin crossing the blood-brain barrier, progressing through early, intermediate, and advanced phases toward kernicterus.
Acute disseminated encephalomyelitis
Acute disseminated encephalomyelitis (ADEM), a monophasic inflammatory demyelinating disease of the brain and spinal cord, mostly in children after infection or rarely vaccination; treated with corticosteroids, generally good prognosis.
Acute encephalopathy with biphasic seizures and late reduced diffusion
AESD (acute encephalopathy with biphasic seizures and late reduced diffusion) is a Japanese-predominant pediatric infection-triggered encephalopathy: prolonged febrile seizure, late seizures days 4–6, bright tree appearance on MRI, HHV-6 or influenza triggers, frequent neurological sequelae.
Acute exudative polymorphous vitelliform maculopathy
Acute exudative polymorphous vitelliform maculopathy (AEPVM) is a rare bilateral retinal disease first described in 1988, marked by yellowish subretinal lesions that usually resolve on their own.
Acute haemorrhagic leukoencephalitis
Acute haemorrhagic leukoencephalitis (Hurst disease), a rare fulminant demyelinating brain disease first described by Weston Hurst in 1941, usually follows respiratory infection, causes hemorrhagic white matter necrosis, and carries roughly 46-58% mortality.
Acute idiopathic maculopathy
Acute idiopathic maculopathy (AIM), first described by Yannuzzi in 1991 as unilateral acute idiopathic maculopathy, is a rare self-limiting RPE and choriocapillaris disorder causing sudden severe central vision loss in young adults after flu-like illness, with spontaneous recovery.
Acute infantile liver failure-cerebellar ataxia-peripheral sensory motor neuropathy syndrome
Acute infantile liver failure-cerebellar ataxia-peripheral sensory motor neuropathy syndrome, also called SCAR21 or CALFAN syndrome, is an autosomal recessive SCYL1-related disorder (OMIM 616719) causing recurrent infantile acute liver failure, low-GGT cholestasis, ataxia, and axonal neuropathy.