U.S. flag

An official website of the United States government

Format

Send to:

Choose Destination

Dysdiadochokinesis

MedGen UID:
115975
Concept ID:
C0234979
Sign or Symptom
Synonym: Dysdiadochokinesia
SNOMED CT: Dysdiadokokinesia (23133003); Dysdiadochokinesis (23133003); Dysdiadokokinesis (23133003)
 
HPO: HP:0002075

Definition

A type of ataxia characterized by the impairment of the ability to perform rapidly alternating movements, such as pronating and supinating his or her hand on the dorsum of the other hand as rapidly as possible. [from HPO]

Term Hierarchy

Conditions with this feature

Ataxia-telangiectasia syndrome
MedGen UID:
439
Concept ID:
C0004135
Disease or Syndrome
Classic ataxia-telangiectasia (A-T) is characterized by progressive cerebellar ataxia beginning between ages one and four years, oculomotor apraxia, choreoathetosis, telangiectasias of the conjunctivae, immunodeficiency, frequent infections, and an increased risk for malignancy, particularly leukemia and lymphoma. Individuals with A-T are unusually sensitive to ionizing radiation. Non-classic forms of A-T have included adult-onset A-T and A-T with early-onset dystonia.
Oromandibular-limb hypogenesis spectrum
MedGen UID:
66357
Concept ID:
C0221060
Disease or Syndrome
The most basic description of Moebius syndrome is a congenital facial palsy with impairment of ocular abduction. The facial nerve (cranial nerve VII) and abducens nerve (CN VI) are most frequently involved, but other cranial nerves may be involved as well. Other variable features include orofacial dysmorphism and limb malformations. Mental retardation has been reported in a subset of patients. Most cases of Moebius syndrome are sporadic, but familial occurrence has been reported (Verzijl et al., 2003). The definition of and diagnostic criteria for Moebius syndrome have been controversial and problematic. The syndrome has most frequently been confused with hereditary congenital facial paresis (HCFP; see 601471), which is restricted to involvement of the facial nerve and no other abnormalities. Verzijl et al. (2003) and Verzijl et al. (2005) concluded that HCFP and Moebius syndrome are distinct disorders, and that Moebius syndrome is a complex developmental disorder of the brainstem. Moebius syndrome was defined at the Moebius Syndrome Foundation Research Conference in 2007 as congenital, nonprogressive facial weakness with limited abduction of one or both eyes. Additional features can include hearing loss and other cranial nerve dysfunction, as well as motor, orofacial, musculoskeletal, neurodevelopmental, and social problems (summary by Webb et al., 2012). Kumar (1990) provided a review of Moebius syndrome, which was critiqued by Lipson et al. (1990). Briegel (2006) provided a review of Moebius sequence with special emphasis on neuropsychiatric findings.
gamma-Glutamyltransferase deficiency
MedGen UID:
82813
Concept ID:
C0268524
Disease or Syndrome
Level of glutathione in the urine above the upper limit of normal.
Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome
MedGen UID:
82815
Concept ID:
C0268540
Disease or Syndrome
Hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome is a disorder of the urea cycle and ornithine degradation pathway. Clinical manifestations and age of onset vary among individuals even in the same family. Neonatal onset (~8% of affected individuals). Manifestations of hyperammonemia usually begin 24-48 hours after feeding begins and can include lethargy, somnolence, refusal to feed, vomiting, tachypnea with respiratory alkalosis, and/or seizures. Infantile, childhood, and adult onset (~92%). Affected individuals may present with: Chronic neurocognitive deficits (including developmental delay, ataxia, spasticity, learning disabilities, cognitive deficits, and/or unexplained seizures); Acute encephalopathy secondary to hyperammonemic crisis precipitated by a variety of factors; and Chronic liver dysfunction (unexplained elevation of liver transaminases with or without mild coagulopathy, with or without mild hyperammonemia and protein intolerance). Neurologic findings and cognitive abilities can continue to deteriorate despite early metabolic control that prevents hyperammonemia.
Hyperlysinemia
MedGen UID:
82816
Concept ID:
C0268553
Disease or Syndrome
Hyperlysinemia type I is an autosomal recessive metabolic condition with variable clinical features. Some patients who present in infancy with nonspecific seizures, hypotonia, or mildly delayed psychomotor development have been found to have increased serum lysine and pipecolic acid on laboratory analysis. However, about 50% of probands are reported to be asymptomatic, and hyperlysinemia is generally considered to be a benign metabolic variant (summary by Tondo et al., 2013; Houten et al., 2013). The AASS gene encodes a bifunctional enzyme: lysine alpha-ketoglutarate reductase and saccharopine dehydrogenase. In hyperlysinemia type I, both enzymatic functions of AASS are defective; in hyperlysinemia type II, also known as saccharopinuria (268700), some of the first enzymatic function is retained (Cox, 1985; Cox et al., 1986).
Ataxic cerebral palsy
MedGen UID:
95998
Concept ID:
C0394005
Disease or Syndrome
A subtype of non-spastic cerebral palsy with loss of muscular coordination with abnormal force and rhythm, and impairment of accuracy; commonly presents with gait and trunk ataxia, poor balance, past pointing, terminal intention tremor, scanning speech, nystagmus and other abnormal eye movements, and hypotonia. Low tone is a prominent feature.
Spinocerebellar ataxia type 1
MedGen UID:
155703
Concept ID:
C0752120
Disease or Syndrome
Spinocerebellar ataxia type 1 (SCA1) is characterized by progressive cerebellar ataxia, dysarthria, and eventual deterioration of bulbar functions. Early in the disease, affected individuals may have gait disturbance, slurred speech, difficulty with balance, brisk deep tendon reflexes, hypermetric saccades, nystagmus, and mild dysphagia. Later signs include slowing of saccadic velocity, development of up-gaze palsy, dysmetria, dysdiadochokinesia, and hypotonia. In advanced stages, muscle atrophy, decreased deep tendon reflexes, loss of proprioception, cognitive impairment (e.g., frontal executive dysfunction, impaired verbal memory), chorea, dystonia, and bulbar dysfunction are seen. Onset is typically in the third or fourth decade, although childhood onset and late-adult onset have been reported. Those with onset after age 60 years may manifest a pure cerebellar phenotype. Interval from onset to death varies from ten to 30 years; individuals with juvenile onset show more rapid progression and more severe disease. Anticipation is observed. An axonal sensory neuropathy detected by electrophysiologic testing is common; brain imaging typically shows cerebellar and brain stem atrophy.
Spinocerebellar ataxia type 2
MedGen UID:
155704
Concept ID:
C0752121
Disease or Syndrome
Spinocerebellar ataxia type 2 (SCA2) is characterized by progressive cerebellar ataxia, including nystagmus, slow saccadic eye movements, and in some individuals, ophthalmoparesis or parkinsonism. Pyramidal findings are present; deep tendon reflexes are brisk early on and absent later in the course. Age of onset is typically in the fourth decade with a ten- to 15-year disease duration.
Spinocerebellar ataxia type 5
MedGen UID:
155705
Concept ID:
C0752123
Disease or Syndrome
For a general discussion of autosomal dominant spinocerebellar ataxia (SCA), see SCA1 (164400).
Optic atrophy 2
MedGen UID:
326915
Concept ID:
C1839576
Disease or Syndrome
A rare form of hereditary optic atrophy seen in only 4 families to date. With onset in early childhood the disease has characteristics of progressive loss of visual acuity, significant optic nerve pallor and occasionally additional neurological manifestations, with females being unaffected.
Fragile X-associated tremor/ataxia syndrome
MedGen UID:
333403
Concept ID:
C1839780
Disease or Syndrome
FMR1 disorders include fragile X syndrome (FXS), fragile X-associated tremor/ataxia syndrome (FXTAS), and fragile X-associated primary ovarian insufficiency (FXPOI). Fragile X syndrome occurs in individuals with an FMR1 full mutation or other loss-of-function variant and is nearly always characterized in affected males by developmental delay and intellectual disability along with a variety of behavioral issues. Autism spectrum disorder is present in 50%-70% of individuals with FXS. Affected males may have characteristic craniofacial features (which become more obvious with age) and medical problems including hypotonia, gastroesophageal reflux, strabismus, seizures, sleep disorders, joint laxity, pes planus, scoliosis, and recurrent otitis media. Adults may have mitral valve prolapse or aortic root dilatation. The physical and behavioral features seen in males with FXS have been reported in females heterozygous for the FMR1 full mutation, but with lower frequency and milder involvement. FXTAS occurs in individuals who have an FMR1 premutation and is characterized by late-onset, progressive cerebellar ataxia and intention tremor followed by cognitive impairment. Psychiatric disorders are common. Age of onset is typically between 60 and 65 years and is more common among males who are hemizygous for the premutation (40%) than among females who are heterozygous for the premutation (16%-20%). FXPOI, defined as hypergonadotropic hypogonadism before age 40 years, has been observed in 20% of women who carry a premutation allele compared to 1% in the general population.
Spinocerebellar ataxia type 18
MedGen UID:
336066
Concept ID:
C1843884
Disease or Syndrome
Disease with characteristics of sensory neuropathy and cerebellar ataxia. Prevalence is unknown. Only 26 cases in a 5-generation American family of Irish ancestry have been reported to date. Onset is in the second and third decades of life with symptomatic onset ranging from 13 to 27 years. Patients initially present with axonal sensory neuropathy, while cerebellar ataxia and motor neuron dysfunction develop later. Linked to chromosome 7q22-q23 but the responsible gene mutation has not yet been identified.
Hereditary spastic paraplegia 7
MedGen UID:
339552
Concept ID:
C1846564
Disease or Syndrome
Spastic paraplegia 7 (SPG7) is characterized by insidiously progressive bilateral leg weakness and spasticity. Most affected individuals have decreased vibration sense and cerebellar signs. Onset is mostly in adulthood, although symptoms may start as early as age 11 years and as late as age 72 years. Additional features including ataxia (gait and limbs), spastic dysarthria, dysphagia, pale optic disks, ataxia, nystagmus, strabismus, ptosis, hearing loss, motor and sensory neuropathy, amyotrophy, scoliosis, pes cavus, and urinary sphincter disturbances may be observed.
Familial isolated deficiency of vitamin E
MedGen UID:
341248
Concept ID:
C1848533
Disease or Syndrome
Ataxia with vitamin E deficiency (AVED) generally manifests in late childhood or early teens between ages five and 15 years. The first symptoms include progressive ataxia, clumsiness of the hands, loss of proprioception, and areflexia. Other features often observed are dysdiadochokinesia, dysarthria, positive Romberg sign, head titubation, decreased visual acuity, and positive Babinski sign. The phenotype and disease severity vary widely among families with different pathogenic variants; age of onset and disease course are more uniform within a given family, but symptoms and disease severity can vary even among sibs.
Neuronal ceroid lipofuscinosis 5
MedGen UID:
376792
Concept ID:
C1850442
Disease or Syndrome
The neuronal ceroid lipofuscinoses (NCL; CLN) are a clinically and genetically heterogeneous group of neurodegenerative disorders characterized by the intracellular accumulation of autofluorescent lipopigment storage material in different patterns ultrastructurally. The lipopigment patterns observed most often in CLN5 comprise mixed combinations of 'granular,' 'curvilinear,' and 'fingerprint' profiles. The clinical course includes progressive dementia, seizures, and progressive visual failure (Mole et al., 2005). For a general phenotypic description and a discussion of genetic heterogeneity of CLN, see CLN1 (256730).
Spinocerebellar ataxia type 34
MedGen UID:
338703
Concept ID:
C1851481
Disease or Syndrome
Spinocerebellar ataxia-34 is an autosomal dominant disorder characterized by slowly progressive cerebellar ataxia. The age at onset is usually during the young adult years, and most patients remain ambulatory until late in life. One family with SCA34 also had onset of erythema and hyperkeratosis in early childhood (Cadieux-Dion et al., 2014), whereas other families have additional neurologic signs, including ocular movement disturbances and pyramidal tract signs (Ozaki et al., 2015). For a general discussion of autosomal dominant spinocerebellar ataxia, see SCA1 (164400).
Dystonia 5
MedGen UID:
342121
Concept ID:
C1851920
Disease or Syndrome
GTP cyclohydrolase 1-deficient dopa-responsive dystonia (GTPCH1-deficient DRD) is characterized by childhood-onset dystonia and a dramatic and sustained response to low doses of oral administration of levodopa. This disorder typically presents with gait disturbance caused by foot dystonia, later development of parkinsonism, and diurnal fluctuation of symptoms (aggravation of symptoms toward the evening and alleviation of symptoms in the morning after sleep). Initial symptoms are often gait difficulties attributable to flexion-inversion (equinovarus posture) of the foot. Occasionally, initial symptoms are arm dystonia, postural tremor of the hand, or slowness of movements. Brisk deep-tendon reflexes in the legs, ankle clonus, and/or the striatal toe (dystonic extension of the big toe) are present in many affected individuals. In general, gradual progression to generalized dystonia is observed. Intellectual, cerebellar, sensory, and autonomic disturbances generally do not occur.
Mast syndrome
MedGen UID:
343325
Concept ID:
C1855346
Disease or Syndrome
Mast syndrome (MASTS) is an autosomal recessive complicated form of hereditary spastic paraplegia in which progressive spastic paraparesis is associated in more advanced cases with cognitive decline, dementia, and other neurologic abnormalities. Symptom onset usually occurs in adulthood, and the disorder is progressive with variable severity. Brain imaging shows thinning of the corpus callosum. The disorder occurs with high frequency in the Old Order Amish (summary by Simpson et al., 2003). For a discussion of genetic heterogeneity of autosomal recessive spastic paraplegia, see SPG5A (270800).
Neurodegeneration with brain iron accumulation 2B
MedGen UID:
346658
Concept ID:
C1857747
Disease or Syndrome
PLA2G6-associated neurodegeneration (PLAN) comprises a continuum of three phenotypes with overlapping clinical and radiologic features: Infantile neuroaxonal dystrophy (INAD). Atypical neuroaxonal dystrophy (atypical NAD). PLA2G6-related dystonia-parkinsonism. INAD usually begins between ages six months and three years with psychomotor regression or delay, hypotonia, and progressive spastic tetraparesis. Many affected children never learn to walk or lose the ability shortly after attaining it. Strabismus, nystagmus, and optic atrophy are common. Disease progression is rapid, resulting in severe spasticity, progressive cognitive decline, and visual impairment. Many affected children do not survive beyond their first decade. Atypical NAD shows more phenotypic variability than INAD. In general, onset is in early childhood but can be as late as the end of the second decade. The presenting signs may be gait instability, ataxia, or speech delay and autistic features, which are sometimes the only evidence of disease for a year or more. Strabismus, nystagmus, and optic atrophy are common. Neuropsychiatric disturbances including impulsivity, poor attention span, hyperactivity, and emotional lability are also common. The course is fairly stable during early childhood and resembles static encephalopathy but is followed by neurologic deterioration between ages seven and 12 years. PLA2G6-related dystonia-parkinsonism has a variable age of onset, but most individuals present in early adulthood with gait disturbance or neuropsychiatric changes. Affected individuals consistently develop dystonia and parkinsonism (which may be accompanied by rapid cognitive decline) in their late teens to early twenties. Dystonia is most common in the hands and feet but may be more generalized. The most common features of parkinsonism in these individuals are bradykinesia, resting tremor, rigidity, and postural instability.
Spinocerebellar ataxia type 12
MedGen UID:
347653
Concept ID:
C1858501
Disease or Syndrome
Rare disease with manifestations of action tremor associated with relatively mild cerebellar ataxia. Associated pyramidal and extrapyramidal signs and dementia have been reported. Prevalence is unknown. Approximately 40 families have been reported. The pathogenesis seems to be related to a toxic effect at the RNA level as it is caused by a CAG expansion at the 5'' end of the PPP2R2B gene on chromosome 5q31-5q32.
Spinocerebellar ataxia type 29
MedGen UID:
350085
Concept ID:
C1861732
Disease or Syndrome
Spinocerebellar ataxia-29 (SCA29) is an autosomal dominant neurologic disorder characterized by onset in infancy of delayed motor development and mild cognitive delay. Affected individuals develop a very slowly progressive or nonprogressive gait and limb ataxia associated with cerebellar atrophy on brain imaging. Additional variable features include nystagmus, dysarthria, and tremor (summary by Huang et al., 2012). For a general discussion of autosomal dominant spinocerebellar ataxia, see SCA1 (164400).
Spastic ataxia 7
MedGen UID:
354750
Concept ID:
C1862441
Disease or Syndrome
A rare hereditary ataxia with characteristics of an apparently non-progressive or slowly progressive symmetrical ataxia of gait, pyramidal signs in the limbs, spasticity and hyperreflexia (especially in the lower limbs) together with dysarthria and impaired pupillary reaction to light, presenting as a fixed miosis. Nystagmus may also be present.
Spinocerebellar ataxia type 10
MedGen UID:
369786
Concept ID:
C1963674
Disease or Syndrome
Spinocerebellar ataxia type 10 (SCA10) is characterized by slowly progressive cerebellar ataxia that usually starts as poor balance and unsteady gait, followed by upper-limb ataxia, scanning dysarthria, and dysphagia. Abnormal tracking eye movements are common. Recurrent seizures after the onset of gait ataxia have been reported with variable frequencies among different families. Some individuals have cognitive dysfunction, behavioral disturbances, mood disorders, mild pyramidal signs, and peripheral neuropathy. Age of onset ranges from 12 to 48 years.
EAST syndrome
MedGen UID:
411243
Concept ID:
C2748572
Disease or Syndrome
Syndrome with characteristics of seizures, sensorineural deafness, ataxia, intellectual deficit, and electrolyte imbalance. It has been described in five patients from four families. The disease is caused by homozygous or compound heterozygous mutations in the KCNJ10 gene, encoding a potassium channel expressed in the brain, spinal cord, inner ear and kidneys. Transmission is autosomal recessive.
Cerebellar ataxia, intellectual disability, and dysequilibrium syndrome 2
MedGen UID:
412914
Concept ID:
C2750234
Disease or Syndrome
Cerebellar ataxia, impaired intellectual development, and dysequilibrium syndrome (CAMRQ) is a genetically heterogeneous disorder characterized by congenital cerebellar ataxia and intellectual disability (summary by Gulsuner et al., 2011). For a discussion of genetic heterogeneity of CAMRQ, see CAMRQ1 (224050).
Hypomyelinating leukodystrophy 8 with or without oligodontia and-or hypogonadotropic hypogonadism
MedGen UID:
482274
Concept ID:
C3280644
Disease or Syndrome
POLR3-related leukodystrophy, a hypomyelinating leukodystrophy with specific features on brain MRI, is characterized by varying combinations of four major clinical findings: Neurologic dysfunction, typically predominated by motor dysfunction (progressive cerebellar dysfunction, and to a lesser extent extrapyramidal [i.e., dystonia], pyramidal [i.e., spasticity] and cognitive dysfunctions). Abnormal dentition (delayed dentition, hypodontia, oligodontia, and abnormally placed or shaped teeth). Endocrine abnormalities such as short stature (in ~50% of individuals) with or without growth hormone deficiency, and more commonly, hypogonadotropic hypogonadism manifesting as delayed, arrested, or absent puberty. Ocular abnormality in the form of myopia, typically progressing over several years and becoming severe. POLR3-related leukodystrophy and 4H leukodystrophy are the two recognized terms for five previously described overlapping clinical phenotypes (initially described as distinct entities before their molecular basis was known). These include: Hypomyelination, hypodontia, hypogonadotropic hypogonadism (4H syndrome); Ataxia, delayed dentition, and hypomyelination (ADDH); Tremor-ataxia with central hypomyelination (TACH); Leukodystrophy with oligodontia (LO); Hypomyelination with cerebellar atrophy and hypoplasia of the corpus callosum (HCAHC). Age of onset is typically in early childhood but later-onset cases have also been reported. An infant with Wiedemann-Rautenstrauch syndrome (neonatal progeroid syndrome) was recently reported to have pathogenic variants in POLR3A on exome sequencing. Confirmation of this as a very severe form of POLR3-related leukodystrophy awaits replication in other individuals with a clinical diagnosis of Wiedemann-Rautenstrauch syndrome.
Spastic ataxia 5
MedGen UID:
482607
Concept ID:
C3280977
Disease or Syndrome
Spastic ataxia-5 (SPAX5) is an autosomal recessive neurodegenerative disorder characterized by early-onset spasticity resulting in significantly impaired ambulation, cerebellar ataxia, oculomotor apraxia, dystonia, and myoclonic epilepsy (summary by Pierson et al., 2011). For a discussion of genetic heterogeneity of spastic ataxia, see SPAX1 (108600).
Hereditary spastic paraplegia 35
MedGen UID:
501249
Concept ID:
C3496228
Disease or Syndrome
Fatty acid hydroxylase-associated neurodegeneration (FAHN) is characterized early in the disease course by central nervous system involvement including corticospinal tract involvement (spasticity), mixed movement disorder (ataxia/dystonia), and eye findings (optic atrophy, oculomotor abnormalities), and later in the disease course by progressive intellectual impairment and seizures. With disease progression, dystonia and spasticity compromise the ability to ambulate, leading to wheelchair dependence. Life expectancy is variable. FAHN is considered to be a subtype of neurodegeneration with brain iron accumulation (NBIA).
Autosomal recessive spinocerebellar ataxia 13
MedGen UID:
766730
Concept ID:
C3553816
Disease or Syndrome
Autosomal recessive spinocerebellar ataxia-13 (SCAR13) is an autosomal recessive neurologic disorder characterized by delayed psychomotor development beginning in infancy. Affected individuals show mildly to profoundly impaired intellectual development with poor or absent speech as well as gait and stance ataxia and hyperreflexia. Most individuals also have eye movement abnormalities. Brain MRI shows cerebellar atrophy and ventriculomegaly (Guergueltcheva et al., 2012).
Mitochondrial complex III deficiency nuclear type 2
MedGen UID:
767519
Concept ID:
C3554605
Disease or Syndrome
Mitochondrial complex III deficiency nuclear type 2 is an autosomal recessive severe neurodegenerative disorder that usually presents in childhood, but may show later onset, even in adulthood. Affected individuals have motor disability, with ataxia, apraxia, dystonia, and dysarthria, associated with necrotic lesions throughout the brain. Most patients also have cognitive impairment and axonal neuropathy and become severely disabled later in life (summary by Ghezzi et al., 2011). The disorder may present clinically as spinocerebellar ataxia or Leigh syndrome, or with psychiatric disturbances (Morino et al., 2014; Atwal, 2014; Nogueira et al., 2013). For a discussion of genetic heterogeneity of mitochondrial complex III deficiency, see MC3DN1 (124000).
Partial lipodystrophy, congenital cataracts, and neurodegeneration syndrome
MedGen UID:
813897
Concept ID:
C3807567
Disease or Syndrome
Lipodystrophies are rare disorders characterized by loss of body fat from various regions and predisposition to metabolic complications of insulin resistance and lipid abnormalities. FPLD7 is an autosomal dominant disorder with a highly variable phenotype. Additional features, including early-onset cataracts and later onset of spasticity of the lower limbs, have been noted in some patients (summary by Garg et al., 2015). For a general phenotypic description and a discussion of genetic heterogeneity of familial partial lipodystrophy (FPLD), see 151660.
Ataxia-telangiectasia-like disorder 1
MedGen UID:
861227
Concept ID:
C4012790
Disease or Syndrome
Ataxia-telangiectasia-like disorder-1 is an autosomal recessive disorder characterized clinically by progressive cerebellar degeneration resulting in ataxia and oculomotor apraxia. Laboratory studies of patient cells showed increased susceptibility to radiation, consistent with a defect in DNA repair. The disorder shares some phenotypic features of ataxia-telangiectasia (AT; 208900), but telangiectases and immune deficiency are not present in ATLD1 (summary by Hernandez et al., 1993 and Stewart et al., 1999). Genetic Heterogeneity of Ataxia-Telangiectasia-Like Disorder See also ATLD2 (615919), caused by mutation in the PCNA gene (176740) on chromosome 20p12.
Autosomal recessive spinocerebellar ataxia 18
MedGen UID:
863942
Concept ID:
C4015505
Disease or Syndrome
Autosomal recessive spinocerebellar ataxia-18 is a neurologic disorder characterized by delayed psychomotor development, severely impaired gait due to cerebellar ataxia, ocular movement abnormalities, and intellectual disability. Brain imaging shows progressive cerebellar atrophy (summary by Hills et al., 2013).
Short stature, microcephaly, and endocrine dysfunction
MedGen UID:
895448
Concept ID:
C4225288
Disease or Syndrome
In patients with SSMED, short stature and microcephaly are apparent at birth, and there is progressive postnatal growth failure. Endocrine dysfunction, including hypergonadotropic hypogonadism, multinodular goiter, and diabetes mellitus, is present in affected adults. Progressive ataxia has been reported in some patients, with onset ranging from the second to fifth decade of life. In addition, a few patients have developed tumors, suggesting that there may be a predisposition to tumorigenesis. In contrast to syndromes involving defects in other components of the nonhomologous end-joining (NHEJ) complex (see, e.g., 606593), no clinically overt immunodeficiency has been observed in SSMED, although laboratory analysis has revealed lymphopenia or borderline leukopenia in some patients (Murray et al., 2015; Bee et al., 2015; de Bruin et al., 2015; Guo et al., 2015).
Lichtenstein-Knorr syndrome
MedGen UID:
898996
Concept ID:
C4225383
Disease or Syndrome
Lichtenstein-Knorr syndrome is an autosomal recessive neurologic disorder characterized by postnatal onset of severe progressive sensorineural hearing loss and progressive cerebellar ataxia. Features usually develop in childhood or young adulthood (summary by Guissart et al., 2015). Some patients with SLC9A1 mutations may not have deafness (Iwama et al., 2018)
Neurodegeneration with ataxia, dystonia, and gaze palsy, childhood-onset
MedGen UID:
934660
Concept ID:
C4310693
Disease or Syndrome
Childhood-onset neurodegeneration with ataxia, dystonia, and gaze palsy (NADGP) is an autosomal recessive progressive disorder characterized by onset of gait ataxia, cognitive decline, and gaze palsy in the first or second decades. Additional features include dysarthria, dystonia, and athetoid movements. Some patients may become wheelchair-bound as young adults (summary by Haack et al., 2016).
Autosomal dominant striatal neurodegeneration type 1
MedGen UID:
934775
Concept ID:
C4310808
Disease or Syndrome
Autosomal dominant striatal degeneration is a neurologic disorder characterized by variable movement abnormalities due to dysfunction in the striatal part of the basal ganglia (summary by Kuhlenbaumer et al., 2004). Genetic Heterogeneity of Autosomal Dominant Striatal Degeneration See also ADSD2 (616922), caused by mutation in the PDE10A gene (610652) on chromosome 6q27.
Spinocerebellar ataxia type 40
MedGen UID:
1385103
Concept ID:
C4518336
Disease or Syndrome
A very rare disease with characteristics of adult-onset unsteady gait and dysarthria, followed by wide-based gait, gait ataxia, ocular dysmetria, intention tremor, scanning speech, hyperreflexia and dysdiadochokinesis.
Spinocerebellar ataxia 44
MedGen UID:
1611168
Concept ID:
C4521563
Disease or Syndrome
Spinocerebellar ataxia, autosomal recessive 26
MedGen UID:
1617917
Concept ID:
C4539948
Disease or Syndrome
Mitochondrial myopathy-cerebellar ataxia-pigmentary retinopathy syndrome
MedGen UID:
1620960
Concept ID:
C4540096
Disease or Syndrome
Mitochondrial myopathy and ataxia (MMYAT) is an autosomal recessive mtDNA depletion disorder characterized by cerebellar ataxia, congenital muscle involvement with histologic findings ranging from myopathic to dystrophic, and pigmentary retinopathy (summary by Donkervoort et al., 2019).
Cerebellar ataxia, intellectual disability, and dysequilibrium syndrome 1
MedGen UID:
1639436
Concept ID:
C4551552
Disease or Syndrome
VLDLR cerebellar hypoplasia (VLDLR-CH) is characterized by non-progressive congenital ataxia that is predominantly truncal and results in delayed ambulation, moderate-to-profound intellectual disability, dysarthria, strabismus, and seizures. Children either learn to walk very late (often after age 6 years) or never achieve independent ambulation. Brain MRI findings include hypoplasia of the inferior portion of the cerebellar vermis and hemispheres, simplified gyration of the cerebral hemispheres, and small brain stem – particularly the pons.
Idiopathic basal ganglia calcification 1
MedGen UID:
1637664
Concept ID:
C4551624
Disease or Syndrome
Primary familial brain calcification (PFBC) is a neurodegenerative disorder with characteristic calcium deposits in the basal ganglia and other brain areas visualized on neuroimaging. Most affected individuals are in good health during childhood and young adulthood and typically present in the fourth to fifth decade with a gradually progressive movement disorder and neuropsychiatric symptoms. The movement disorder first manifests as clumsiness, fatigability, unsteady gait, slow or slurred speech, dysphagia, involuntary movements, or muscle cramping. Neuropsychiatric symptoms, often the first or most prominent manifestations, range from mild difficulty with concentration and memory to changes in personality and/or behavior, to psychosis and dementia. Seizures of various types occur frequently, some individuals experience chronic headache and vertigo; urinary urgency or incontinence may be present.
Autosomal recessive spinocerebellar ataxia 14
MedGen UID:
1636182
Concept ID:
C4706415
Disease or Syndrome
Autosomal recessive spinocerebellar ataxia-14 (SCAR14) is a neurologic disorder characterized by delayed psychomotor development, severe early-onset gait ataxia, eye movement abnormalities, cerebellar atrophy on brain imaging, and impaired intellectual development (summary by Lise et al., 2012).
Parkinsonism-dystonia, infantile, 2
MedGen UID:
1648382
Concept ID:
C4747991
Disease or Syndrome
Infantile-onset parkinsonism-dystonia-2 (PKDYS2) is an autosomal recessive complex infantile-onset neurologic disorder characterized by abnormal movements, including parkinsonism, dystonia, and poor fine motor skills, as well as autonomic dysfunction, including abnormal sweating, cold extremities, and poor sleep. Some patients have variable degrees of developmental delay. Features of the disorder are consistent with decreased levels of monoamine neurotransmitters, although levels of these in the spinal fluid are normal (summary by Rilstone et al., 2013). For a discussion of genetic heterogeneity of PKDYS, see 613135.
Neurodevelopmental disorder with central and peripheral motor dysfunction
MedGen UID:
1674767
Concept ID:
C5193049
Disease or Syndrome
Neurodevelopmental disorder with central and peripheral motor dysfunction (NEDCPMD) is an autosomal recessive neurologic disorder with a highly variable phenotype. At the severe end of the spectrum, patients may have hypotonia apparent from birth, necessitating mechanical respiration and tube-feeding, and global developmental delay with absence of reaction to touch and no eye contact. At the mild end of the spectrum, patients may present with infantile-onset progressive ataxia and demyelinating peripheral neuropathy. The disorder is caused by mutation in the NFASC gene, which has several neuronal- and glial-specific transcripts. The variable clinical phenotype may be caused by several factors, including the severity of the mutation, the selective involvement of distinct isoforms by pathogenic variants, and the presence of genetic modifiers (summary by Monfrini et al., 2019).
Microcephaly, developmental delay, and brittle hair syndrome
MedGen UID:
1718781
Concept ID:
C5394425
Disease or Syndrome
Microcephaly, developmental delay, and brittle hair syndrome (MDBH) is a multisystem disorder with clinical variability. Affected individuals show cognitive and motor disabilities, as well as some degree of fine, brittle hair with microscopic shaft abnormalities. Other shared features include failure to thrive in early childhood and short stature, with some patients exhibiting feeding difficulties and hepatic steatosis (Kuo et al., 2019).
Cerebellar dysfunction, impaired intellectual development, and hypogonadotropic hypogonadism
MedGen UID:
1808634
Concept ID:
C5676924
Disease or Syndrome
Cerebellar dysfunction, impaired intellectual development, and hypogonadotropic hypogonadism (CDIDHH) is characterized by delayed motor development, ataxia, severe progressive scoliosis, moderate to severe intellectual disability, and delayed sexual development. Cerebellar hypoplasia has been observed in some patients (Whittaker et al., 2021).
Spinocerebellar ataxia 49
MedGen UID:
1805601
Concept ID:
C5676950
Disease or Syndrome
Spinocerebellar ataxia-49 (SCA49) is an autosomal dominant neurologic disorder characterized initially by gait abnormalities, gaze-evoked nystagmus, and hyperreflexia. The age at onset is highly variable, ranging from the second to seventh decades, even within the same family. The disorder is slowly progressive, and later features may include dysarthria, dysmetria, diplopia, pyramidal signs, and axonal peripheral neuropathy. Brain imaging shows cerebellar atrophy and myelination defects (Corral-Juan et al., 2022).
Peripheral motor neuropathy, childhood-onset, biotin-responsive
MedGen UID:
1809728
Concept ID:
C5676997
Disease or Syndrome
Childhood-onset biotin-responsive peripheral motor neuropathy (COMNB) is an autosomal recessive disorder characterized predominantly by the onset of distal muscle weakness and atrophy late in the first decade of life. The disorder predominantly affects the upper limbs and hands, resulting in difficulties with fine motor skills. Some patients may have lower limb involvement, resulting in gait difficulties. Electrophysiologic studies and muscle biopsy are consistent with chronic denervation with axonal and demyelinating features. Rare patients may have additional neurologic signs, including spasticity, ataxia, and cerebellar signs. Sensation is intact, and patients have normal cognitive development. Treatment with biotin, pantothenic acid, and lipoic acid may result in clinical improvement (Holling et al., 2022).
Dystonia 22, juvenile-onset
MedGen UID:
1841281
Concept ID:
C5830645
Disease or Syndrome
Juvenile-onset dystonia-22 (DYT22JO) is an autosomal recessive disorder characterized by progressive, generalized dystonia associated with cognitive decline and cerebellar atrophy on brain imaging (Mencacci et al., 2021).

Recent clinical studies

Etiology

Wentz E, Gillberg IC, Anckarsäter H, Gillberg C, Råstam M
Eur Child Adolesc Psychiatry 2012 Aug;21(8):421-32. Epub 2012 Apr 7 doi: 10.1007/s00787-012-0274-9. PMID: 22484429
Rasova K, Dolezil D, Kalistova H, Kucera P, Juzova O, Zimova D, Medova E, Jandova D, Tintera J, Ibrahim I, Zvara K, Bicikova M, Martinkova P
Neuro Endocrinol Lett 2012;33(1):67-75. PMID: 22467115
Louis ED, Lynch T, Ford B, Greene P, Bressman SB, Fahn S
Arch Neurol 1996 May;53(5):450-4. doi: 10.1001/archneur.1996.00550050080027. PMID: 8624221
Gillberg C, Råstam M, Gillberg IC
Dev Med Child Neurol 1994 Jul;36(7):567-75. doi: 10.1111/j.1469-8749.1994.tb11893.x. PMID: 8034118
Oder W, Grimm G, Kollegger H, Ferenci P, Schneider B, Deecke L
J Neurol 1991 Aug;238(5):281-7. doi: 10.1007/BF00319740. PMID: 1919612

Diagnosis

Burkle FM, Hadley KS, Ridge LL, Herman JK, Kobeissy FH
Mil Med 2022 Jul 1;187(7-8):e921-e925. doi: 10.1093/milmed/usab371. PMID: 34632519
Perju-Dumbrava L, Lau K, Phyland D, Papanikolaou V, Finlay P, Beare R, Bardin P, Stuckey S, Kempster P, Thyagarajan D
PLoS One 2017;12(11):e0186611. Epub 2017 Nov 3 doi: 10.1371/journal.pone.0186611. PMID: 29099841Free PMC Article
Wentz E, Gillberg IC, Anckarsäter H, Gillberg C, Råstam M
Eur Child Adolesc Psychiatry 2012 Aug;21(8):421-32. Epub 2012 Apr 7 doi: 10.1007/s00787-012-0274-9. PMID: 22484429
Wnorowski M, Prosch H, Prayer D, Janssen G, Gadner H, Grois N
J Pediatr 2008 Jul;153(1):127-32. Epub 2008 Feb 11 doi: 10.1016/j.jpeds.2007.12.042. PMID: 18571550
Gillberg C, Råstam M, Gillberg IC
Dev Med Child Neurol 1994 Jul;36(7):567-75. doi: 10.1111/j.1469-8749.1994.tb11893.x. PMID: 8034118

Therapy

Jha A, Pai NM, Ganjekar S, Desai G, Chaturvedi SK
Int Clin Psychopharmacol 2021 Mar 1;36(2):106-108. doi: 10.1097/YIC.0000000000000341. PMID: 33136660
Bradberry SM, Sheehan TM, Barraclough CR, Vale JA
Clin Toxicol (Phila) 2009 Nov;47(9):894-8. doi: 10.3109/15563650903333812. PMID: 19852623
Guney F, Gumus H, Ogmegul A, Kandemir B, Emlik D, Arslan U, Tuncer I
Clin Neurol Neurosurg 2008 Jul;110(7):739-42. Epub 2008 May 21 doi: 10.1016/j.clineuro.2008.04.002. PMID: 18499339
Gautschi OP, Cadosch D, Zellweger R
Neurol India 2007 Oct-Dec;55(4):393-5. doi: 10.4103/0028-3886.37099. PMID: 18040116
Kumar G, Kang CA, Giannini C
J Gen Intern Med 2007 Sep;22(9):1373-6. Epub 2007 Jul 6 doi: 10.1007/s11606-007-0272-7. PMID: 17619108Free PMC Article

Prognosis

Rong P, Yunusova Y, Eshghi M, Rowe HP, Green JR
Amyotroph Lateral Scler Frontotemporal Degener 2020 Feb;21(1-2):34-41. Epub 2019 Nov 7 doi: 10.1080/21678421.2019.1681454. PMID: 31694409Free PMC Article
Perju-Dumbrava L, Lau K, Phyland D, Papanikolaou V, Finlay P, Beare R, Bardin P, Stuckey S, Kempster P, Thyagarajan D
PLoS One 2017;12(11):e0186611. Epub 2017 Nov 3 doi: 10.1371/journal.pone.0186611. PMID: 29099841Free PMC Article
Wnorowski M, Prosch H, Prayer D, Janssen G, Gadner H, Grois N
J Pediatr 2008 Jul;153(1):127-32. Epub 2008 Feb 11 doi: 10.1016/j.jpeds.2007.12.042. PMID: 18571550
Louis ED, Lynch T, Ford B, Greene P, Bressman SB, Fahn S
Arch Neurol 1996 May;53(5):450-4. doi: 10.1001/archneur.1996.00550050080027. PMID: 8624221
Oder W, Grimm G, Kollegger H, Ferenci P, Schneider B, Deecke L
J Neurol 1991 Aug;238(5):281-7. doi: 10.1007/BF00319740. PMID: 1919612

Clinical prediction guides

Rong P, Yunusova Y, Eshghi M, Rowe HP, Green JR
Amyotroph Lateral Scler Frontotemporal Degener 2020 Feb;21(1-2):34-41. Epub 2019 Nov 7 doi: 10.1080/21678421.2019.1681454. PMID: 31694409Free PMC Article
Perju-Dumbrava L, Lau K, Phyland D, Papanikolaou V, Finlay P, Beare R, Bardin P, Stuckey S, Kempster P, Thyagarajan D
PLoS One 2017;12(11):e0186611. Epub 2017 Nov 3 doi: 10.1371/journal.pone.0186611. PMID: 29099841Free PMC Article
Frints SG, Borghgraef M, Froyen G, Marynen P, Fryns JP
Am J Med Genet 2002 Nov 1;112(4):361-8. doi: 10.1002/ajmg.10630. PMID: 12376938
Sanders RD, Keshavan MS, Forman SD, Pieri JN, McLaughlin N, Allen DN, van Kammen DP, Goldstein G
Psychiatry Res 2000 Sep 11;95(3):237-43. doi: 10.1016/s0165-1781(00)00176-1. PMID: 10974362
Oder W, Grimm G, Kollegger H, Ferenci P, Schneider B, Deecke L
J Neurol 1991 Aug;238(5):281-7. doi: 10.1007/BF00319740. PMID: 1919612

Supplemental Content

Table of contents

    Clinical resources

    Consumer resources

    Recent activity

    Your browsing activity is empty.

    Activity recording is turned off.

    Turn recording back on

    See more...