{"Name":"Cystic leukoencephalopathy without megalencephaly","DiseaseID__c":"GARD:0013199","id":13199,"encodedName":"cystic-leukoencephalopathy-without-megalencephaly","IsDeleted":false,"Disease_Name_Full__c":"Cystic leukoencephalopathy without megalencephaly","Xref_IDs__c":"720825005; C2751843; C567845; DOID:0081007; MEDGEN:416646; MONDO:0013058; OMIM:612951; ORPHA:85136","USA_Estimate__c":"1,000","No_of_Specialist_Tagsa__c":3,"No_of_ClinGen_records__c":0,"No_of_GeneReviews__c":0,"No_of_HHS_records__c":1,"World_Estimate__c":"1 to 8,000","No_of_HRSA_records__c":0,"Evidence_Based_Score__c":1,"No_of_Disease_Descriptions__c":5,"Disease_Characteristics_Score__c":7,"No_of_Age_at_Onset__c":2,"Description_Source__c":"MONDO:0013058","Disease_Description__c":"Cystic leukoencephalopathy without megalencephaly is characterised by non-progressive leukoencephalopathy, bilateral cysts in the anterior part of the temporal lobe, cerebral white matter anomalies and severe psychomotor impairment. Less than 50 patients have been described in the literature so far. Inheritance is most likely autosomal recessive.","GARD_Name__c":"Cystic leukoencephalopathy without megalencephaly","GARD_Synonym__c":"clwm","Curated_Disease_Description_Source__c":"MEDGEN:C2751843","Curated_Disease_Description__c":"Cystic leukoencephalopathy without megalencephaly (also known as RNAse T2-deficient leukoencephalopathy) is a disorder that affects the brain. People with cystic leukoencephalopathy without megalencephaly have neurological problems that become apparent during infancy; the problems generally do not worsen over time (progress). Most affected individuals have severe intellectual disability; muscle stiffness (spasticity); and a delay in developing motor skills such as sitting, crawling, and walking. Some do not learn to walk, and most do not develop the ability to speak. Other neurological features that can occur in cystic leukoencephalopathy without megalencephaly include hearing loss caused by abnormalities in the inner ear (sensorineural deafness), seizures, involuntary writhing movements of the hands (athetosis), uncontrolled muscle tensing (dystonia), and involuntary eye movements (nystagmus). In addition to the neurological problems associated with this disorder, some affected individuals have unusual facial features sometimes described as a \"doll-like face.\" The neurological problems in this disorder are caused by abnormalities in the brain. People with this condition have leukoencephalopathy, an abnormality of the brain's white matter that can be detected with medical imaging. White matter consists of nerve fibers covered by a fatty substance called myelin. Myelin insulates nerve fibers and promotes the rapid transmission of nerve impulses. In people with cystic leukoencephalopathy without megalencephaly, myelin is not made in sufficient amounts during development, leading to patchy white matter abnormalities (lesions) in the brain. In addition, individuals with cystic leukoencephalopathy without megalencephaly may have cysts in regions of the brain called the temporal lobes and enlargement of the fluid-filled cavities (ventricles) near the center of the brain. The white matter lesions are primarily concentrated around the cysts and the ventricles. An abnormally small head and brain size (microcephaly) often occurs in this disorder.","Curated_USA_Estimate_Source__c":null,"Curated_USA_Estimate__c":"1,000","Age_at_Onset_Snippet_Text__c":"as a Newborn and as an Infant","SourceID__c":"ORPHA:85136","Deprecated__c":"No","Disease_Concept_Type__c":"Rare Disease Entity","MONDO_ID__c":"MONDO:0013058","ORPHANET_ID__c":"ORPHA:85136","Replaced_By_ID__c":null,"Display_Spanish_Disease_Name__c":"Leucoencefalopatía quística sin megalencefalia","Spanish_Description_Source__c":"ORPHA:85136","Spanish_Description__c":"Es un trastorno caracterizado por leucoencefalopatía no progresiva, quistes bilaterales en la parte anterior del lóbulo temporal, anomalías en la sustancia blanca cerebral y afectación psicomotora grave. Hasta la fecha se han descrito menos de 50 pacientes en la literatura. Probablemente la herencia sea autosómica recesiva.","Spanish_Disease_Name__c":"leucoencefalopatía quística sin megalencefalia","Spanish_GARD_Synonym__c":"clwm","Category_Linearization__c":"ORPHA:98006","icd10_id__c":null,"mesh_id__c":null,"omim_id__c":null,"snomed_id__c":null,"umls_id__c":null,"GARD_Disease__c":[{"Curated_Disease_Description__c":"Cystic leukoencephalopathy without megalencephaly (also known as RNAse T2-deficient leukoencephalopathy) is a disorder that affects the brain. People with cystic leukoencephalopathy without megalencephaly have neurological problems that become apparent during infancy; the problems generally do not worsen over time (progress). Most affected individuals have severe intellectual disability; muscle stiffness (spasticity); and a delay in developing motor skills such as sitting, crawling, and walking. Some do not learn to walk, and most do not develop the ability to speak. Other neurological features that can occur in cystic leukoencephalopathy without megalencephaly include hearing loss caused by abnormalities in the inner ear (sensorineural deafness), seizures, involuntary writhing movements of the hands (athetosis), uncontrolled muscle tensing (dystonia), and involuntary eye movements (nystagmus). In addition to the neurological problems associated with this disorder, some affected individuals have unusual facial features sometimes described as a \"doll-like face.\" The neurological problems in this disorder are caused by abnormalities in the brain. People with this condition have leukoencephalopathy, an abnormality of the brain's white matter that can be detected with medical imaging. White matter consists of nerve fibers covered by a fatty substance called myelin. Myelin insulates nerve fibers and promotes the rapid transmission of nerve impulses. In people with cystic leukoencephalopathy without megalencephaly, myelin is not made in sufficient amounts during development, leading to patchy white matter abnormalities (lesions) in the brain. In addition, individuals with cystic leukoencephalopathy without megalencephaly may have cysts in regions of the brain called the temporal lobes and enlargement of the fluid-filled cavities (ventricles) near the center of the brain. The white matter lesions are primarily concentrated around the cysts and the ventricles. An abnormally small head and brain size (microcephaly) often occurs in this disorder.","Curated_Disease_Description_Source__c":"MEDGEN:C2751843","GARD_Synonym__c":"clwm","Name":"Cystic leukoencephalopathy without megalencephaly","Curated_USA_Estimate__c":"1,000","estimateUsa":"1,000"}],"Organization_Supported_Diseases__c":[{"Account_Name__c":"Metabolic Support UK","Website__c":"https://www.metabolicsupportuk.org"}],"GARD_Disease_Tag__c":[{"Tag_Name__c":"Genetics","Tag_Category__c":"Cause;Disease Category;Specialist","category_description":"Genetic diseases affect the DNA, or genetic instructions, which directs how tissues, organs, and body systems function.","curated_tag_name":"Genetic diseases"},{"Tag_Name__c":"Neurology","Tag_Category__c":"Disease Category;Specialist","category_description":"Neurological diseases affect the brain, spinal cord, cranial nerves, autonomic nerves, or other peripheral nerves.","curated_tag_name":"Neurological diseases"},{"Tag_Name__c":"Leukodystrophy","Tag_Category__c":"Account;Cause;Disease Category","category_description":"Leukodystrophies are a group of genetic neurological diseases that affect the white matter of the brain and spinal cord.","curated_tag_name":"Leukodystrophies"},{"Tag_Name__c":"Pediatrics","Tag_Category__c":"Specialist"}],"Age_At_Onset__c":[{"Age_At_Onset__c":"Neonatal","Provided_By__c":"ORPHA:85136"},{"Age_At_Onset__c":"Infancy","Provided_By__c":"ORPHA:85136"}],"Diagnosis__c":[{"Type__c":"GTR","Curie__c":"MEDGEN:C2751843"}],"External_Identifier_Disease__c":[{"URL__c":"https://raresource.nih.gov/diseases/filter/0013199","Source__c":"RareSource"},{"URL__c":"https://www.orpha.net/en/disease/detail/85136","Source__c":"C2751843; MONDO:0013058; ORPHA:85136","Xref__c":"ORPHA:85136"},{"URL__c":"https://www.ebi.ac.uk/ols4/ontologies/doid/classes?obo_id=DOID%3A0081007","Source__c":"MONDO:0013058","Xref__c":"DOID:0081007"},{"URL__c":"https://uts.nlm.nih.gov/uts/umls/concept/C2751843","Source__c":"C2751843","Xref__c":"C2751843"},{"URL__c":"https://www.ncbi.nlm.nih.gov/mesh/C567845","Source__c":"MONDO:0013058","Xref__c":"C567845"},{"URL__c":"https://www.ncbi.nlm.nih.gov/medgen/?term=416646","Source__c":"C2751843","Xref__c":"MEDGEN:416646"},{"URL__c":"https://www.omim.org/entry/612951","Source__c":"C2751843; MONDO:0013058","Xref__c":"OMIM:612951"},{"URL__c":"https://browser.ihtsdotools.org/?perspective=full&conceptId1=720825005","Source__c":"C2751843; MONDO:0013058","Xref__c":"720825005"},{"URL__c":"http://purl.obolibrary.org/obo/MONDO_0013058","Source__c":"GARD:0013199","Xref__c":"MONDO:0013058"},{"URL__c":"https://medlineplus.gov/genetics/condition/rnase-t2-deficient-leukoencephalopathy","Source__c":"GARD:0013199","Xref__c":"https://medlineplus.gov/genetics/condition/rnase-t2-deficient-leukoencephalopathy"}],"GARD_Disease_Gene__c":[{"GeneSymbol__c":"RNASET2","GHR_URL__c":"https://medlineplus.gov/genetics/gene/rnaset2","Gene_Type__c":"protein-coding gene","Causal_Gene__c":true}],"Inheritance__c":["Autosomal recessive"],"GARD_Disease_Feature__c":[{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001250","HPO_Synonym__c":"Epileptic seizure; Seizures","HPO_Name__c":"Seizure","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"An abnormally increased muscular tone that causes fixed abnormal postures. There is a slow, intermittent twisting motion that leads to exaggerated turning and posture of the extremities and trunk.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001332","HPO_Synonym__c":"Dystonic movements","HPO_Name__c":"Dystonia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"An abnormality of myelination of nerves in the central nervous system.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0011400","HPO_Synonym__c":"Abnormal formation of myelin sheaths","HPO_Name__c":"Abnormal CNS myelination","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Head circumference below 2 standard deviations below the mean for age and sex.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000252","HPO_Synonym__c":"Abnormally small cranium; Abnormally small skull; Decreased circumference of cranium; Decreased size of cranium; Decreased size of skull; Reduced head circumference; small cranium; Small head circumference","HPO_Name__c":"Microcephaly","Feature_System__c":"Nervous System; Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"A slow, continuous, involuntary writhing movement that prevents maintenance of a stable posture. Athetosis involves continuous smooth movements that appear random and are not composed of recognizable sub-movements or movement fragments. In contrast to chorea, in athetosis, the same regions of the body are repeatedly involved. Athetosis may worsen with attempts at movement of posture, but athetosis can also occur at rest.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002305","HPO_Synonym__c":"Athetoid movements; Involuntary writhing movements; Involuntary writhing movements in fingers, hands, toes, and feet","HPO_Name__c":"Athetosis","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","Feature__r":{"HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0007042","HPO_Name__c":"Focal white matter lesions","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000639","HPO_Synonym__c":"Involuntary, rapid, rhythmic eye movements","HPO_Name__c":"Nystagmus","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"A severe delay in the achievement of motor or mental milestones in the domains of development of a child.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0011344","HPO_Synonym__c":"Global developmental delay, severe","HPO_Name__c":"Severe global developmental delay","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"A degree of language development that is significantly below the norm for a child of a specified age.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000750","HPO_Synonym__c":"Deficiency of speech development; Delayed language development; Delayed speech; Delayed speech acquisition; Delayed speech and language development; Delayed speech development; Impaired speech and language development; Impaired speech development; Language delay; Language delayed; Language development deficit; Late-onset speech development; Poor language development; Speech and language delay; Speech and language difficulties; Speech delay","HPO_Name__c":"Delayed speech and language development","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Ataxia refers to impaired coordination of voluntary muscle movement. Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001251","HPO_Synonym__c":"Cerebellar ataxia","HPO_Name__c":"Ataxia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"An increase in size of the ventricular system of the brain.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002119","HPO_Synonym__c":"Cerebral ventricular dilatation; Dilated cerebral ventricle; Dilated cerebral ventricles; Dilated ventricles; Enlarged cerebral ventricles; Enlarged ventricles; Enlarged ventricular system; Large cerebral ventricles and cisternae; Ventricular dilatation","HPO_Name__c":"Ventriculomegaly","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001263","HPO_Synonym__c":"Delayed cognitive development; Delayed development; Delayed developmental milestones; Delayed intellectual development; Delayed milestones; Delayed psychomotor development; Developmental delay; Developmental delay in early childhood; Developmental delay, global; Developmental retardation; GDD; Lack of psychomotor development; Motor and developmental delay; Motormental retardation; Psychomotor delay; Psychomotor development deficiency; Psychomotor development failure; Psychomotor developmental delay; Retarded development; Retarded mental development; Retarded psychomotor development","HPO_Name__c":"Global developmental delay","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"The presence of calcium deposition within the cerebrum.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002514","HPO_Synonym__c":"Abnormal deposits of calcium in the brain","HPO_Name__c":"Cerebral calcification","Feature_System__c":"Nervous System; Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"A characteristic facial appearance with a round facial form, full cheeks, a short nose, and a relatively small chin.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000295","HPO_Synonym__c":"Doll-like facial appearance","HPO_Name__c":"Doll-like facies","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"This term describes abnormality of the white matter of the cerebrum resulting from damage to the myelin sheaths of nerve cells.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002352","HPO_Name__c":"Leukoencephalopathy","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"A type of hearing impairment in one or both ears related to an abnormal functionality of the cochlear nerve.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000407","HPO_Synonym__c":"Hearing loss, sensorineural; Sensorineural deafness; Sensorineural hearing loss","HPO_Name__c":"Sensorineural hearing impairment","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001257","HPO_Synonym__c":"Involuntary muscle stiffness, contraction, or spasm; Muscle spasticity; Muscular spasticity","HPO_Name__c":"Spasticity","Feature_System__c":"Nervous System; Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:612951","Feature__r":{"HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002465","HPO_Synonym__c":"Poor speech","HPO_Name__c":"Poor speech","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}}],"tags":{"Cause":["Genetics","Leukodystrophy"],"Disease Category":["Genetics","Neurology","Leukodystrophy"],"Specialist":["Genetics","Neurology","Pediatrics"],"Account":["Leukodystrophy"]},"synonyms":["clwm"]}