1,527 articles
Corneal scars or opacities
Corneal scars or opacities (leukoma; ICD-10 H17, ICD-11 9A77) are loss of corneal transparency from scarring by infectious, inflammatory, congenital, dystrophic, or traumatic causes, treated mainly by keratoplasty.
Corneal staphyloma
Corneal staphyloma (anterior staphyloma) is a rare ectatic, uveal-lined bulging of an opaque cornea, congenital or acquired after corneal perforation, treated by sclerokeratoplasty or penetrating keratoplasty rather than evisceration.
Corpus callosum agenesis-abnormal genitalia syndrome
Corpus callosum agenesis-abnormal genitalia syndrome, also called Proud syndrome, is a rare X-linked recessive ARX-gene disorder combining agenesis of the corpus callosum, severe intellectual disability, seizures, spasticity, and abnormal genitalia, mainly affecting males.
Corpus callosum agenesis-neuronopathy syndrome
Corpus callosum agenesis-neuronopathy syndrome, or Andermann syndrome (HMSN/ACC, ACCPN), is a rare autosomal recessive SLC12A6/KCC3 disorder with progressive sensorimotor neuropathy, callosal dysgenesis, and a Quebec founder population.
Corticobasal syndrome
Corticobasal syndrome (CBS), also called corticobasal degeneration syndrome, is a clinical disorder of asymmetric rigidity, apraxia, and myoclonus caused most often by corticobasal degeneration, a 4R tauopathy, but also by PSP or Alzheimer's disease.
Cramp-fasciculation syndrome
Cramp-fasciculation syndrome (CFS) is a benign peripheral nerve hyperexcitability disorder causing cramps, muscle twitching, stiffness, and exercise intolerance without weakness; named by Tahmoush in 1991 and treated with carbamazepine.
Cranio-cervical dystonia with laryngeal and upper-limb involvement
Cranio-cervical dystonia with laryngeal and upper-limb involvement, or DYT24, is a rare genetic dystonia combining cervical, laryngeal, and facial symptoms with tremor, caused by ANO3 variants.
Craniofacial-deafness-hand syndrome
Craniofacial-deafness-hand syndrome (CDHS, Sommer-Young-Wee-Frye syndrome, OMIM 122880) is an extremely rare autosomal dominant PAX3 disorder with flat facies, hypertelorism, profound congenital sensorineural deafness, and ulnar deviation with hand contractures.
Craniosynostosis
Craniosynostosis, also called craniostenosis, is the premature fusion of cranial sutures, occurring in about 1 in 2000-2500 births; sagittal suture most often involved, treated surgically in infancy.
Crushing injury of head
Crushing injury of head (ICD-11 NA08; ICD-10 S07): damage to head tissues from a crushing external force, subdivided into brain, face, skull, and scalp crush injuries; a rare blunt-force mechanism counted among traumatic brain injury codes.
Cryptogenic late-onset epileptic spasms
Cryptogenic late-onset epileptic spasms (ORPHA:163708, late-onset infantile spasms) is a rare epilepsy syndrome with spasms after age 1 year in clusters, tonic seizures, atypical absences, cognitive deterioration, and temporal/temporofrontal EEG focus without hypsarrhythmia.
Cubital tunnel syndrome
Cubital tunnel syndrome (CuTS), ulnar nerve entrapment at the elbow, is the second most common upper-limb compression neuropathy, causing little and ring finger numbness worsened by elbow flexion; treated first conservatively, then by in situ decompression or transposition.
Cyst in the anterior chamber of the eye
Cyst in the anterior chamber of the eye (ICD-11 9A82), usually an iris cyst; primary pigment epithelial cysts are typically stationary, while secondary implantation cysts after trauma or surgery enlarge and cause glaucoma, requiring aspiration, laser, or excision.
Cystic leukoencephalopathy without megalencephaly
Cystic leukoencephalopathy without megalencephaly (CLWM) is a rare inherited brain disorder, described in 2005, with temporal lobe cysts, normal head size, and severe psychomotor impairment.
D,L-2-hydroxyglutaric aciduria
D,L-2-hydroxyglutaric aciduria (combined D-2- and L-2-HGA, OMIM 615182) is a rare autosomal recessive SLC25A1 citrate carrier defect causing severe neonatal epileptic encephalopathy with elevated D- and L-2-hydroxyglutarate, usually lethal early in life.
Dacryocystitis
Dacryocystitis, inflammation or infection of the lacrimal sac (tear sac), usually from nasolacrimal duct obstruction. Acute and chronic forms; treated with antibiotics and dacryocystorhinostomy; congenital cases often resolve by age one.
Dacryolith
Dacryolith (tear stone, 涙石): a concretion of the lacrimal drainage system, ICD-11 9A11.6, found in 6-18% of DCR patients, composed mainly of proteins, mucins, and TFF peptides, treated by extraction.
Deafblindness
Deafblindness, also called dual sensory loss or dual sensory impairment, is the combination of hearing and vision loss in one person; its most common genetic cause is Usher syndrome.
Deafness with labyrinthine aplasia, microtia, and microdontia
LAMM syndrome, also called congenital deafness with inner ear agenesis, microtia, and microdontia (OMIM 610706), is a rare autosomal recessive FGF3-related disorder combining profound congenital deafness, absent inner ear structures, small ears, and small widely spaced teeth.
Deafness-intellectual disability syndrome, Martin-Probst type
Martin-Probst syndrome (ORPHA:85321, OMIM 300519) is a rare X-linked recessive disorder with congenital sensorineural hearing loss, intellectual disability, short stature, and facial dysmorphism; the proposed RAB40AL p.D59G cause has been reclassified as non-pathogenic.
Deep gluteal syndrome
Deep gluteal syndrome (DGS), formerly piriformis syndrome, is non-discogenic sciatic nerve entrapment in the deep gluteal space causing buttock pain and sciatica; diagnosed by provocation tests and pelvic MRI, treated conservatively first.
Degenerative high myopia
Degenerative high myopia, also called pathologic myopia, is a form of myopia in which excessive elongation of the eyeball causes structural damage that can lead to vision loss.
Dejerine-Sottas syndrome
Dejerine-Sottas syndrome (DSS), also CMT3 or HMSN III, is a severe infantile-onset demyelinating Charcot-Marie-Tooth phenotype with nerve conduction below 10-12 m/s, areflexia, and foot deformities, caused by PMP22, MPZ, EGR2, or PRX mutations.
Delayed sleep-wake phase disorder
Delayed sleep-wake phase disorder (DSWPD, formerly DSPS/DSPD), ICD-11 7A60: a circadian rhythm sleep-wake disorder with persistently delayed sleep timing; normal sleep on a delayed schedule; affects about 1% of adults, 3.3-4.6% of adolescents; treated with timed melatonin and light therapy.
Dementia due to cerebrovascular disease
Dementia due to cerebrovascular disease (ICD-11 6D81), or vascular dementia, is dementia from ischemic or hemorrhagic brain injury, with prominent processing-speed and executive deficits, stepwise or progressive course, and frequent overlap with Alzheimer's pathology.
Demyelinating disease
A demyelinating disease is a disorder in which the myelin sheath around nerve fibers is damaged, slowing or blocking nerve signals; multiple sclerosis is the most common form.
Dentatorubral pallidoluysian atrophy
Dentatorubral pallidoluysian atrophy (DRPLA, Naito-Oyanagi disease, Haw River syndrome) is a rare autosomal dominant CAG repeat expansion disorder of the ATN1 gene causing ataxia, myoclonus, epilepsy, chorea, and dementia, most common in Japan.
Desiderosmia
Desiderosmia is the excessive craving to smell specific odours without wanting to ingest them, associated with iron deficiency anaemia; term coined by Hansen et al. 2017, distinct from pica, resolves with iron replacement.
Desmoplastic infantile astrocytoma/ganglioglioma
Desmoplastic infantile astrocytoma/ganglioglioma (DIA/DIG, ICD-O 9412/1) is a rare WHO grade 1 infant brain tumor, a large cystic supratentorial desmoplastic mass driven by BRAF/RAF1 MAPK alterations, treated mainly by surgery with favorable prognosis.
Developmental and epileptic encephalopathy with spike-wave activation in sleep
DEE-SWAS, also called EE-SWAS and formerly ESES or CSWS, is a rare childhood epilepsy syndrome with regression of cognition, language, behavior, or motor skills tied to marked sleep-activated 1.5–2 Hz spike-and-wave EEG activity, onset at 2–12 years.