- Cardiac arrest (HP:0001695): An abrupt loss of heart function. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- 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: 2/4. (PMID:35147173)
- 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: 1/4. (PMID:35147173)
- 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: 3/4. (PMID:35147173)
- Nonimmune hydrops fetalis (HP:0001790): A type of hydrops fetalis in which there is no identifiable circulating antibody to red blood cell antigens . Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Reduced visual acuity (HP:0007663). Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Death in infancy (HP:0001522): Death within the first 24 months of life. Evidence: PCS. Frequency: 2/4. (PMID:35147173)
- Diabetes insipidus (HP:0000873): A state of excessive water intake and hypotonic (dilute) polyuria. Diabetes insipidus may be due to failure of vasopressin (AVP) release (central or neurogenic diabetes insipidus) or to a failure of the kidney to respond to AVP (nephrogenic diabetes insipidus). Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Hyperorality (HP:0000710): Hyperorality is a condition characterized by an excessive preoccupation with oral sensations and behaviors, such as chewing, sucking, biting, swallowing, and excessive mouthing of objects. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Neonatal onset (HP:0003623): Onset of signs or symptoms of disease within the first 28 days of life. Evidence: PCS. Frequency: 2/4. (PMID:35147173)
- Cerebral atrophy (HP:0002059): Atrophy (wasting, decrease in size of cells or tissue) affecting the cerebrum. Evidence: PCS. Frequency: 2/4. (PMID:35147173)
- Developmental regression (HP:0002376): Loss of developmental skills, as manifested by loss of developmental milestones. Evidence: PCS. Frequency: 1/1. (PMID:35147173)
- Nephrogenic diabetes insipidus (HP:0009806): A form of diabetes insipidus caused by failure of the kidneys to respond to vasopressin (AVP). Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- 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: 1/4. (PMID:35147173)
- Fetal pleural effusion (HP:0025676): Fetal pleural effusion is the accumulation of excess fluid in the layers of tissue (pleura) lining the lungs and wall of the chest. It may be primary, also termed hydrothorax, occurring as an isolated finding or it may be secondary, most commonly resulting from non-immune hydrops. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Decreased activity of mitochondrial complex III (HP:0011924): A reduction in the activity of the mitochondrial respiratory chain complex III, which is part of the electron transport chain in mitochondria. Evidence: PCS. Frequency: 1/1. (PMID:35147173)
- 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:35147173)
- Secondary microcephaly (HP:0005484): Head circumference which falls below 2 standard deviations below the mean for age and gender because of insufficient head growth after birth. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Left ventricular noncompaction cardiomyopathy (HP:0011664): Left ventricular non-compaction (LVNC) is characterized by prominent left ventricular trabeculae and deep inter-trabecular recesses. The myocardial wall is often thickened with a thin, compacted epicardial layer and a thickened endocardial layer. In some patients, LVNC is associated with left ventricular dilatation and systolic dysfunction, which can be transient in neonates. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Decreased activity of mitochondrial complex I (HP:0011923): A reduction in the activity of the mitochondrial respiratory chain complex I, which is part of the electron transport chain in mitochondria. Evidence: PCS. Frequency: 1/1. (PMID:35147173)
- Bull's eye maculopathy (HP:0011504): Progressive maculopathy characterized by concentric regions of hyper- and hypopigmentation, with an initial foveal sparing and whose appearance is said to resemble the central target of a dart board. Evidence: PCS. Frequency: 3/4. (PMID:35147173)
- 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: 1/4. (PMID:35147173)
- Reduced cerebral white matter volume (HP:0034295): An abnormally low volume of the white matter of the brain. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Hypertrophic cardiomyopathy (HP:0001639): Hypertrophic cardiomyopathy (HCM) is defined by the presence of increased ventricular wall thickness or mass in the absence of loading conditions (hypertension, valve disease) sufficient to cause the observed abnormality. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Sensorineural hearing impairment (HP:0000407): A type of hearing impairment in one or both ears related to an abnormal functionality of the cochlear nerve. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Small for gestational age (HP:0001518): Smaller than normal size according to sex and gestational age related norms, defined as a weight below the 10th percentile for the gestational age. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Central hypoventilation (HP:0007110). Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Unexplained fevers (HP:0001955): Episodes of fever for which no infectious cause can be identified. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- 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:35147173)
- Decreased activity of mitochondrial complex IV (HP:0008347): A reduction in the activity of the mitochondrial respiratory chain complex IV, which is part of the electron transport chain in mitochondria. Evidence: PCS. Frequency: 1/1. (PMID:35147173)
- Epileptic encephalopathy (HP:0200134): A condition in which epileptiform abnormalities are believed to contribute to the progressive disturbance in cerebral function. Epileptic encephalaopathy is characterized by (1) electrographic EEG paroxysmal activity that is often aggressive, (2) seizures that are usually multiform and intractable, (3) cognitive, behavioral and neurological deficits that may be relentless, and (4) sometimes early death. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Neonatal death (HP:0003811): Death within the first 28 days of life. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Apnea (HP:0002104): Lack of breathing with no movement of the respiratory muscles and no exchange of air in the lungs. This term refers to a disposition to have recurrent episodes of apnea rather than to a single event. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Central diabetes insipidus (HP:0000863): A form of diabetes insipidus related to a failure of vasopressin (AVP) release from the hypothalamus. Evidence: PCS. Frequency: 1/4. (PMID:35147173)
- Myoclonus (HP:0001336): Very brief, involuntary random muscular contractions occurring at rest, in response to sensory stimuli, or accompanying voluntary movements. Evidence: PCS. Frequency: 2/4. (PMID:35147173)
These phenotypes are associated with the disease combined oxidative phosphorylation deficiency 57 (OMIM:620167).