- Decreased liver function (HP:0001410): Reduced ability of the liver to perform its functions. Evidence: PCS. Frequency: 2/2. (PMID:12910490)
- Delayed CNS myelination (HP:0002188): Delayed myelination in the central nervous system. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- Hearing impairment (HP:0000365): A decreased magnitude of the sensory perception of sound. Evidence: TAS. Frequency: Occasional (HP:0040283). (OMIM:124000)
- Aminoaciduria (HP:0003355): An increased concentration of an amino acid in the urine. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- Tubulointerstitial nephritis (HP:0001970): A form of inflammation of the kidney affecting the interstitium of the kidneys surrounding the tubules. Evidence: TAS. (OMIM:124000)
- Hypertyrosinemia (HP:0003231): An increased concentration of tyrosine in the blood. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- 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: IEA. (OMIM:124000)
- Elevated circulating alkaline phosphatase concentration (HP:0003155): Abnormally increased serum levels of alkaline phosphatase activity. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- 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: IEA. (OMIM:124000)
- 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: IEA. (OMIM:124000)
- Generalized hypotonia (HP:0001290): Generalized muscular hypotonia (abnormally low muscle tone). Evidence: TAS. (OMIM:124000)
- Hyperglycemia (HP:0003074): An increased concentration of glucose in the blood. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- Cataract (HP:0000518): A cataract is an opacity or clouding that develops in the crystalline lens of the eye or in its capsule. Evidence: IEA. (OMIM:124000)
- Depression (HP:0000716): Frequently experiencing feelings of being down, miserable, and/or hopeless; struggling to recover from these moods; having a pessimistic outlook on the future; feeling a pervasive sense of shame; having a low self-worth; experiencing thoughts of suicide and engaging in suicidal behavior. Evidence: IEA. (OMIM:124000)
- Emotional lability (HP:0000712): Unstable emotional experiences and frequent mood changes; emotions that are easily aroused, intense, and/or disproportionate to events and circumstances. Evidence: IEA. (OMIM:124000)
- Periportal fibrosis (HP:0001405): The presence of fibrosis affecting the interlobular stroma of liver. Evidence: PCS. Frequency: 2/2. (PMID:12910490)
- Muscle weakness (HP:0001324): Reduced strength of muscles. Evidence: IEA. (OMIM:124000)
- Rod-cone dystrophy (HP:0000510): An inherited retinal disease subtype in which the rod photoreceptors appear to be more severely affected than the cone photoreceptors. Typical presentation is with nyctalopia (due to rod dysfunction) followed by loss of mid-peripheral field of vision, which gradually extends and leaves many patients with a small central island of vision due to the preservation of macular cones. Evidence: IEA. (OMIM:124000)
- Intellectual disability (HP:0001249): The term intellectual disability or intellectual developmental disorder is used to describe significantly sub-average intellectual and adaptive functioning based on clinical assessment and as measured by individually administered, appropriately normed, standardized and validated tests of intellectual functioning and adaptive behavior, with onset during the developmental period from infancy through adolescence. Evidence: IEA. (OMIM:124000)
- Decreased mitochondrial complex III activity in liver tissue (HP:0006558): Decreased activity of complex III of the mitochondrion in the liver. Evidence: IEA. (OMIM:124000)
- Exercise intolerance (HP:0003546): A functional motor deficit where individuals whose responses to the challenges of exercise fail to achieve levels considered normal for their age and gender. Evidence: IEA. (OMIM:124000)
- EEG abnormality (HP:0002353): Abnormality observed by electroencephalogram (EEG), which is used to record of the brain's spontaneous electrical activity from multiple electrodes placed on the scalp. Evidence: IEA. (OMIM:124000)
- Ragged-red muscle fibers (HP:0003200): An abnormal appearance of muscle fibers observed on muscle biopsy. Ragged red fibers can be visualized with Gomori trichrome staining as irregular and intensely red subsarcolemmal zones, whereas the normal myofibrils are green. The margins of affect fibers appear red and ragged. The ragged-red is due to the accumulation of abnormal mitochondria below the plasma membrane of the muscle fiber, leading to the appearance of a red rim and speckled sarcoplasm. Evidence: IEA. (OMIM:124000)
- Rhabdomyolysis (HP:0003201): Breakdown of muscle fibers that leads to the release of muscle fiber contents (myoglobin) into the bloodstream. Evidence: IEA. (OMIM:124000)
- 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: 2/2. (PMID:12910490)
- 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:12910490)
- 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: IEA. (OMIM:124000)
- Elevated gamma-glutamyltransferase level (HP:0030948): Increased level of the enzyme gamma-glutamyltransferase (GGT). GGT is mainly present in kidney, liver, and pancreatic cells, but small amounts are present in other tissues. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- 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:12910490)
- Cholangitis (HP:0030151): Inflammation of the biliary ductal system, affecting the intrahepatic or extrahepatic portions, or both. Evidence: TAS. (OMIM:124000)
- 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: TAS. (OMIM:124000)
- Microvesicular hepatic steatosis (HP:0001414): A form of hepatic steatosis characterized by the presence of small, lipid-laden vesicles in the affected hepatocytes. Evidence: PCS. Frequency: 2/2. (PMID:12910490)
- Mitochondrial encephalopathy (HP:0006789). Evidence: IEA. (OMIM:124000)
- Hepatic steatosis (HP:0001397): Steatosis is a term used to denote lipid accumulation within hepatocytes. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- Cholestasis (HP:0001396): Impairment of bile flow due to obstruction in bile ducts. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- Congenital onset (HP:0003577): A phenotypic abnormality that is present at birth. Evidence: PCS. Frequency: 2/2. (PMID:12910490)
- 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: 1/2. (PMID:12910490)
- Elevated lactate:pyruvate ratio (HP:0032653): An abnormal increase in the molar ratio of lactate to pyruvate in the blood circulation. Evidence: PCS. Frequency: 2/2. (PMID:12910490)
- 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:12910490)
- Hallucinations (HP:0000738): Perceptions in a conscious and awake state that, in the absence of external stimuli, have qualities of real perception. These perceptions are vivid, substantial, and located in external objective space. Evidence: IEA. (OMIM:124000)
- Mitochondrial inheritance (HP:0001427): A mode of inheritance that is observed for traits related to a gene encoded on the mitochondrial genome. Because the mitochondrial genome is essentially always maternally inherited, a mitochondrial condition can only be transmitted by females, although the condition can affect both sexes. The proportion of mutant mitochondria can vary (heteroplasmy). Evidence: IEA. (OMIM:124000)
- Recurrent hypoglycemia (HP:0001988): Recurrent episodes of decreased concentration of glucose in the blood. Evidence: PCS. Frequency: 2/2. (PMID:12910490)
- Feeding difficulties in infancy (HP:0008872): Impaired feeding performance of an infant as manifested by difficulties such as weak and ineffective sucking, brief bursts of sucking, and falling asleep during sucking. There may be difficulties with chewing or maintaining attention. Evidence: IEA. (OMIM:124000)
- Hypoglycemia (HP:0001943): A decreased concentration of glucose in the blood. Evidence: PCS. Frequency: 2/2. (PMID:12910490)
- Lacticaciduria (HP:0003648): An increased concentration of lactic acid in the urine. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- Elevated circulating hepatic transaminase concentration (HP:0002910): Elevations of the levels of SGOT and SGPT in the serum. SGOT (serum glutamic oxaloacetic transaminase) and SGPT (serum glutamic pyruvic transaminase) are transaminases primarily found in the liver and heart and are released into the bloodstream as the result of liver or heart damage. SGOT and SGPT are used clinically mainly as markers of liver damage. Evidence: PCS. Frequency: 2/2. (PMID:12910490)
- 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: 2/2. (PMID:12910490)
- Hyperreflexia (HP:0001347): Hyperreflexia is the presence of hyperactive stretch reflexes of the muscles. Evidence: TAS. (OMIM:124000)
- 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: 2/2. (PMID:12910490)
- Axial hypotonia (HP:0008936): Muscular hypotonia (abnormally low muscle tone) affecting the musculature of the trunk. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- Cerebral atrophy (HP:0002059): Atrophy (wasting, decrease in size of cells or tissue) affecting the cerebrum. Evidence: TAS. (OMIM:124000)
- Brittle hair (HP:0002299): Fragile, easily breakable hair, i.e., with reduced tensile strength. Evidence: TAS. (OMIM:124000)
- Gliosis (HP:0002171): Gliosis is the focal proliferation of glial cells in the central nervous system. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- 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: IEA. (OMIM:124000)
- Ptosis (HP:0000508): The upper eyelid margin is positioned 3 mm or more lower than usual and covers the superior portion of the iris (objective); or, the upper lid margin obscures at least part of the pupil (subjective). Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- Neonatal death (HP:0003811): Death within the first 28 days of life. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
- Severe lactic acidosis (HP:0004900): A severe form of lactic acidemia. Evidence: PCS. Frequency: 1/2. (PMID:12910490)
These phenotypes are associated with the disease mitochondrial complex III deficiency nuclear type 1 (OMIM:124000).