Clinical Signs and Symptoms
ORPHA:395 Homocystinuria due to methylene tetrahydrofolate reductase deficiency
The phenotypic description of this disease is based on an analysis of the biomedical literature and uses the terms of the Human Phenotype Ontology (HPO). Phenotypic abnormalities are presented by order of frequency of occurrence in the patient population, then by alphabetical order inside each frequency group.
- Abnormal enzyme/coenzyme activity HP:0012379
- Behavioral abnormality HP:0000708
- Cystathioninemia HP:0003286
- Gait disturbance HP:0001288
- Homocystinuria HP:0002156
- Hyperhomocystinemia HP:0002160
- Lower limb muscle weakness HP:0007340
- Lower limb spasticity HP:0002061
- Morphological abnormality of the central nervous system HP:0002011
- Upper motor neuron dysfunction HP:0002493
Very frequent
- Abnormality of the periventricular white matter HP:0002518
- Ataxia HP:0001251
- Brain imaging abnormality HP:0410263
- Hypomethioninemia HP:0003658
- Mental deterioration HP:0001268
- Peripheral neuropathy HP:0009830
- Psychotic episodes HP:0000725
- Seizures HP:0001250
- Spastic paraparesis HP:0002313
Frequent
- Abnormal thrombosis HP:0001977
- Abnormality of the cerebral white matter HP:0002500
- Apnea HP:0002104
- Atrophy of the spinal cord HP:0006827
- Brain atrophy HP:0012444
- Cognitive impairment HP:0100543
- Deep venous thrombosis HP:0002625
- Failure to thrive HP:0001508
- Feeding difficulties in infancy HP:0008872
- Focal-onset seizure HP:0007359
- Generalized neonatal hypotonia HP:0008935
- Generalized tonic-clonic seizures HP:0002069
- Global developmental delay HP:0001263
- Headache HP:0002315
- Hemiparesis HP:0001269
- Intellectual disability HP:0001249
- Lethargy HP:0001254
- Psychosis HP:0000709
- Psychotic mentation HP:0001345
- Specific learning disability HP:0001328
- Thromboembolic stroke HP:0001727
Occasional
- Abnormality of the eye HP:0000478
- Absence seizure HP:0002121
- Encephalopathy HP:0001298
- Generalized myoclonic seizures HP:0002123
- Hydrocephalus HP:0000238
- Microcephaly HP:0000252
- Nystagmus HP:0000639
- Optic atrophy HP:0000648
- Stroke HP:0001297
- Ventriculomegaly HP:0002119
Rare
Additional information
Further information
Specialised Social Services
Warning
The information provided is based on published scientific articles.
The information provided is estimated for the entire population of patients in routine care. Some phenotypic abnormalities reported here may occur individually with a variable temporality or severity, while others, not listed, may still be encountered. Phenotypic annotations are not yet available for all rare diseases; the annotation process is ongoing.
The information contained in Orphanet is regularly updated. It is possible that discoveries have been made since the last update and have not yet been incorporated.
Professionals are encouraged to always consult the latest scientific publications before making a decision based on the information provided. The information contained in Orphanet is not intended to replace the services of a healthcare professional. Orphanet cannot be held responsible for the deleterious, truncated or erroneous use of any information found in the Orphanet database.