- Microcephaly (HP:0000252): Head circumference below 2 standard deviations below the mean for age and gender. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Choreoathetosis (HP:0001266): Involuntary movements characterized by both athetosis (inability to sustain muscles in a fixed position) and chorea (widespread jerky arrhythmic movements). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Neonatal hypotonia (HP:0001319): Muscular hypotonia (abnormally low muscle tone) manifesting in the neonatal period. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Failure to thrive (HP:0001508): Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Pancreatitis (HP:0001733): The presence of inflammation in the pancreas. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Renal tubular acidosis (HP:0001947): Acidosis owing to malfunction of the kidney tubules with accumulation of metabolic acids and hyperchloremia, potentially leading to complications including hypokalemia, hypercalcinuria, nephrolithiasis and nephrocalcinosis. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Organic aciduria (HP:0001992): Excretion of non-amino organic acids in urine. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Hypoplasia of the corpus callosum (HP:0002079): Underdevelopment of the corpus callosum. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Ventriculomegaly (HP:0002119): An increase in size of the ventricular system of the brain. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Hyperlysinemia (HP:0002161): The concentration of lysine in the blood circulation is above the upper limit of normal. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Progressive encephalopathy (HP:0002448). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Nonprogressive cerebellar ataxia (HP:0002470). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Progressive spastic quadriplegia (HP:0002478). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Decreased activity of NADPH oxidase (HP:0003206). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Decreased circulating carnitine concentration (HP:0003234): Concentration of carnitine in the blood circulation below the lower limit of normal. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Stress/infection-induced lactic acidosis (HP:0004897): A form of lactic acidemia that occurs in relation to stress or infection. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Central sleep apnea (HP:0010536): Sleep apnea results from a temporary loss of the central drive to the muscles responsible for breathing. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Abnormal circulating carnitine concentration (HP:0010967): Any deviation from the normal concentration of carnitine in the blood circulation. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Aspiration pneumonia (HP:0011951): Pneumonia due to the aspiration (breathing in) of food, liquid, or gastric contents into the upper respiratory tract. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Abnormal involuntary eye movements (HP:0012547): Anomalous movements of the eyes that occur without the subject wanting them to happen. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- Abnormal basal ganglia MRI signal intensity (HP:0012751): A deviation from normal signal on magnetic resonance imaging (MRI) of the basal ganglia. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
- 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:431361)
These phenotypes are associated with the disease Progressive encephalopathy with leukodystrophy due to DECR deficiency (ORPHA:431361).