- Encephalopathy (HP:0001298): Encephalopathy is a term that means brain disease, damage, or malfunction. In general, encephalopathy is manifested by an altered mental state. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Poor head control (HP:0002421): Difficulty to maintain correct position of the head while standing or sitting. Infant head lag is observed when the head seems to flop around or lags posteriorly behind the trunk. Several articles have maintained that head lag should be absent by age 3 to 4 months. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Clonus (HP:0002169): A series of rhythmic and involuntary muscle contractions (at a frequency of about 5 to 7 Hz) that occur in response to an abruptly applied and sustained stretch. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Delayed CNS myelination (HP:0002188): Delayed myelination in the central nervous system. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Dystonia (HP:0001332): 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. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Hypermetropia (HP:0000540): An abnormality of refraction characterized by the ability to see objects in the distance clearly, while objects nearby appear blurry. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Hyperlysinuria (HP:0003297): An increased concentration of lysine in the urine. Evidence: PCS. Frequency: 2/2. (PMID:24847004;PMID:27940755)
- Seizure (HP:0001250): 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. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Cerebellar atrophy (HP:0001272): Cerebellar atrophy is defined as a cerebellum with initially normal structures, in a posterior fossa with normal size, which displays enlarged fissures (interfolial spaces) in comparison to the foliae secondary to loss of tissue. Cerebellar atrophy implies irreversible loss of tissue and result from an ongoing progressive disease until a final stage is reached or a single injury, e.g. an intoxication or infectious event. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Reduced liver 2,4-dienoyl-CoA reductase activity (HP:0034919): Diminished activity of the enzyme 2,4-dienoyl-CoA reductase in liver tissue. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Reduced muscle 2,4-dienoyl-CoA reductase activity (HP:0034918): Diminished activity of the enzyme 2,4-dienoyl-CoA reductase in muscle tissue. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Hypotonia (HP:0001252): Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist. Evidence: PCS. Frequency: 1/1. Onset: Neonatal onset (HP:0003623). (PMID:24847004)
- Hypotonia (HP:0001252): Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Ataxia (HP:0001251): 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). Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Hyperlysinemia (HP:0002161): The concentration of lysine in the blood circulation is above the upper limit of normal. Evidence: PCS. Frequency: 2/2. (PMID:24847004;PMID:27940755)
- Elevated circulating 2-trans,4-cis-decadienoylcarnitine concentration (HP:6000478): The concentration of 2-trans,4-cis-decadienoylcarnitine in the blood circulation is above the upper limit of normal. Evidence: PCS. (PMID:2332510)
- Failure to thrive (HP:0001508): Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Cerebral visual impairment (HP:0100704): A form of loss of vision caused by damage to the visual cortex rather than a defect in the eye. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Hydrocephalus (HP:0000238): Hydrocephalus is an active distension of the ventricular system of the brain resulting from inadequate passage of CSF from its point of production within the cerebral ventricles to its point of absorption into the systemic circulation. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Ventriculomegaly (HP:0002119): An increase in size of the ventricular system of the brain. Evidence: PCS. Frequency: 2/2. (PMID:24847004;PMID:27940755)
- Death in infancy (HP:0001522): Death within the first 24 months of life. Evidence: TAS. (OMIM:616034)
- Decreased plasma free carnitine (HP:0008315): A decreased concentration of free (unbound) carnitine in the blood. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Leukodystrophy (HP:0002415): Leukodystrophy refers to deterioration of white matter of the brain resulting from degeneration of myelin sheaths in the CNS. Their basic defect is directly related to the synthesis and maintenance of myelin membranes. Symmetric white matter involvement at MRI is a typical finding in patients with leukodystrophies. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Metabolic acidosis (HP:0001942): Metabolic acidosis (MA) is characterized by a fall in blood pH due to a reduction of serum bicarbonate concentration. This can occur as a result of either the accumulation of acids (high anion gap MA) or the loss of bicarbonate from the gastrointestinal tract or the kidney (hyperchloremic MA). By definition, MA is not due to a respirary cause. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Incoordination (HP:0002311): A deficit in coordination of muscle movements. Coordination is defined as the orchestrated movement of multiple body parts as required to accomplish intended actions, like walking. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Cerebral atrophy (HP:0002059): Atrophy (wasting, decrease in size of cells or tissue) affecting the cerebrum. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Microcephaly (HP:0000252): Head circumference below 2 standard deviations below the mean for age and gender. Evidence: PCS. Frequency: 2/2. (PMID:24847004;PMID:27940755)
- Abnormality of eye movement (HP:0000496): An abnormality in voluntary or involuntary eye movements or their control. Evidence: TAS. (OMIM:616034)
- Choreoathetosis (HP:0001266): Involuntary movements characterized by both athetosis (inability to sustain muscles in a fixed position) and chorea (widespread jerky arrhythmic movements). Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Colpocephaly (HP:0030048): Colpocephaly is an anatomic finding in the brain manifested by occipital horns that are disproportionately enlarged in comparison with other parts of the lateral ventricles. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Hypoplasia of the corpus callosum (HP:0002079): Underdevelopment of the corpus callosum. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Feeding difficulties (HP:0011968): Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Poor suck (HP:0002033): An inadequate sucking reflex, resulting in the difficult of newborns to be breast-fed. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Global developmental delay (HP:0001263): 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. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Increased circulating lactate concentration (HP:0002151): Abnormally increased level of blood lactate (2-hydroxypropanoic acid). Lactate is produced from pyruvate by lactate dehydrogenase during normal metabolism. The terms lactate and lactic acid are often used interchangeably but lactate (the component measured in blood) is strictly a weak base whereas lactic acid is the corresponding acid. Lactic acidosis is often used clinically to describe elevated lactate but should be reserved for cases where there is a corresponding acidosis (pH below 7.35). Evidence: PCS. Frequency: 2/2. (PMID:24847004;PMID:27940755)
- Increased CSF lysine concentration (HP:0500208): Abnormally increased levels of lysine in cerebrospinal fluid. Evidence: PCS. Frequency: 2/2. (PMID:24847004;PMID:27940755)
- Increased CSF lactate (HP:0002490): Increased concentration of lactate in the cerebrospinal fluid. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Myoclonic absence seizure (HP:0011150): Myoclonic absence seizure is a type of generalized non-motor (absence) seizure characterized by an interruption of ongoing activities, a blank stare and rhythmic three-per-second myoclonic movements, causing ratcheting abduction of the upper limbs leading to progressive arm elevation, and associated with 3 Hz generalized spike-wave discharges on the electroencephalogram. Duration is typically 10-60 s. Whilst impairment of consciousness may not be obvious the ILAE classified this seizure as a generalized non-motor seizure in 2017. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Third trimester onset (HP:0034197): This term refers to a phenotypic feature that was first observed prior to birth during the third trimester, which is defined as 28 weeks and zero days (28+0) of gestation and beyond. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Death in childhood (HP:0003819): Death in during childhood, defined here as between the ages of 2 and 10 years. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Generalized hyperreflexia (HP:0007034). Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Ophthalmoplegia (HP:0000602): Paralysis of one or more extraocular muscles that are responsible for eye movements. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:24847004)
- Optic atrophy (HP:0000648): Atrophy of the optic nerve. Optic atrophy results from the death of the retinal ganglion cell axons that comprise the optic nerve and manifesting as a pale optic nerve on fundoscopy. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Intrauterine growth retardation (HP:0001511): An abnormal restriction of fetal growth with fetal weight below the tenth percentile for gestational age. Evidence: PCS. Frequency: 1/1. (PMID:27940755)
- Spasticity (HP:0001257): A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
- Tetraplegia (HP:0002445): Paralysis of all four limbs, and trunk of the body below the level of an associated injury to the spinal cord. The etiology of quadriplegia is similar to that of paraplegia except that the lesion is in the cervical spinal cord rather than in the thoracic or lumbar segments of the spinal cord. Evidence: PCS. Frequency: 1/1. (PMID:24847004)
These phenotypes are associated with the disease progressive encephalopathy with leukodystrophy due to DECR deficiency (OMIM:616034).