- Hyperketonemia (HP:0410175): An increase in the level of ketone bodies (acetoacetic acid, beta-hydroxybutyric acid, and acetone) in the blood. Evidence: PCS. Frequency: 1/1. (PMID:24781756)
- Generalized hypotonia (HP:0001290): Generalized muscular hypotonia (abnormally low muscle tone). Evidence: PCS. Frequency: 1/1. (PMID:24781756)
- 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:24781756)
- Hyperammonemia (HP:0001987): An increased concentration of ammonia in the blood. Evidence: PCS. Frequency: 1/1. (PMID:24781756)
- Ventriculomegaly (HP:0002119): An increase in size of the ventricular system of the brain. Evidence: PCS. Frequency: 1/1. (PMID:24781756)
- Muscle weakness (HP:0001324): Reduced strength of muscles. Evidence: PCS. Frequency: 2/2. Onset: Juvenile onset (HP:0003621). (PMID:18499082)
- Mental deterioration (HP:0001268): Loss of previously present mental abilities, generally in adults. Evidence: PCS. Frequency: 2/2. Onset: Juvenile onset (HP:0003621). (PMID:18499082)
- 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: 2/2. (PMID:18499082)
- Undetectable visual evoked potentials (HP:0007965). Evidence: PCS. (PMID:18499082)
- 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: 11/11. (PMID:18499082;PMID:24781756)
- Cytochrome C oxidase-negative muscle fibers (HP:0003688): An abnormally reduced activity of the enzyme cytochrome C oxidase in muscle tissue. Evidence: PCS. Frequency: 1/1. (PMID:24781756)
- Myalgia (HP:0003326): Pain in muscle. Evidence: PCS. Onset: Juvenile onset (HP:0003621). (PMID:18499082)
- Hyperalaninemia (HP:0003348): An increased concentration of alanine in the blood. Evidence: PCS. Frequency: 1/1. (PMID:24781756)
- Lactic acidosis (HP:0003128): An abnormal buildup of lactic acid in the body, leading to acidification of the blood and other bodily fluids. Evidence: PCS. Frequency: 1/1. (PMID:24781756)
- Visual loss (HP:0000572): Loss of visual acuity (implying that vision was better at a certain time point in life). Otherwise the term reduced visual acuity should be used (or a subclass of that). Evidence: PCS. Frequency: 2/2. (PMID:18499082)
- Truncal ataxia (HP:0002078): Truncal ataxia is a sign of ataxia characterized by instability of the trunk. It usually occurs during sitting. Evidence: PCS. (PMID:18499082)
- Cardiomegaly (HP:0001640): Increased size of the heart, clinically defined as an increased transverse diameter of the cardiac silhouette that is greater than or equal to 50% of the transverse diameter of the chest (increased cardiothoracic ratio) on a posterior-anterior projection of a chest radiograph or a computed tomography. Evidence: PCS. Frequency: 1/1. (PMID:24781756)
- 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:24781756)
- 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: 3/3. (PMID:18499082;PMID:24781756)
- Increased CSF lactate (HP:0002490): Increased concentration of lactate in the cerebrospinal fluid. Evidence: PCS. (PMID:18499082)
- Limb ataxia (HP:0002070): A kind of ataxia that affects movements of the extremities. Evidence: PCS. (PMID:18499082)
- Pulmonary arterial hypertension (HP:0002092): Pulmonary hypertension is defined mean pulmonary artery pressure of 25mmHg or more and pulmonary capillary wedge pressure of 15mmHg or less when measured by right heart catheterisation at rest and in a supine position. Evidence: PCS. Frequency: 1/1. (PMID:24781756)
- Tricuspid regurgitation (HP:0005180): Failure of the tricuspid valve to close sufficiently upon contraction of the right ventricle, causing blood to regurgitate (flow backward) into the right atrium. Evidence: PCS. Frequency: 1/1. (PMID:24781756)
- 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: 1/1. (PMID:24781756)
- 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:18499082)
- Ventricular hypertrophy (HP:0001714): Enlargement of the cardiac ventricular muscle tissue with increase in the width of the wall of the ventricle and loss of elasticity. Ventricular hypertrophy is clinically differentiated into left and right ventricular hypertrophy. Evidence: PCS. Frequency: 1/1. (PMID:24781756)
- 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:24781756)
These phenotypes are associated with the disease mitochondrial complex IV deficiency, nuclear type 7 (OMIM:619051).