Phenotypes associated with the disease striatonigral degeneration, infantile, mitochondrial (OMIM:500003):
- 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: 1/2. (PMID:7668837)
- 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: 1/3. (PMID:7668837)
- 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:8554662)
- Lingual dystonia (HP:0031008): Involuntary protrusions, movements, spams and contortions of the tongue. Evidence: PCS. Frequency: 1/2. (PMID:7668837)
- Motor tics (HP:0100034): Movement-based tics affecting discrete muscle groups. Evidence: PCS. Frequency: 1/2. (PMID:7668837)
- Striatal T2 hyperintensity (HP:0031206): Abnormally bright T2 signal from the striatum on brain magnetic resonance imaging. Evidence: PCS. Frequency: 1/2. (PMID:7668837)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 2/2. (PMID:7668837)
- 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: PCS. (PMID:8554662)
- Frequent falls (HP:0002359). Evidence: PCS. Frequency: 1/1. (PMID:8554662)
- Headache (HP:0002315): Cephalgia, or pain sensed in various parts of the head, not confined to the area of distribution of any nerve. Evidence: PCS. Frequency: 1/2. (PMID:7668837)
- Ophthalmoparesis (HP:0000597): Ophthalmoplegia is a paralysis or weakness of one or more of the muscles that control eye movement. Evidence: PCS. Frequency: 1/2. (PMID:7668837)
- Brisk reflexes (HP:0001348): Tendon reflexes that are noticeably more active than usual (conventionally denoted 3+ on clinical examination). Brisk reflexes may or may not indicate a neurological lesion. They are distinguished from hyperreflexia by the fact that hyerreflexia is characterized by hyperactive repeating (clonic) reflexes, which are considered to be always abnormal. Evidence: PCS. Frequency: 2/2. (PMID:7668837)
- 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: PCS. Frequency: 2/2. (PMID:7668837)
- Decreased light- and dark-adapted electroretinogram amplitude (HP:0000654): Decreased amplitude of eletrical response upon electroretinography. Evidence: IEA. (OMIM:500003)
- 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: 2/4. (PMID:7668837)
- 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:500003)
- Babinski sign (HP:0003487): Upturning of the big toe (and sometimes fanning of the other toes) in response to stimulation of the sole of the foot. If the Babinski sign is present it can indicate damage to the corticospinal tract. Evidence: PCS. Frequency: 2/3. (PMID:8554662;PMID:7668837)
- Gait disturbance (HP:0001288): The term gait disturbance can refer to any disruption of the ability to walk. Evidence: PCS. Frequency: 1/1. Onset: Childhood onset (HP:0011463). (PMID:8554662)
- Facial grimacing (HP:0000273). Evidence: PCS. Frequency: 1/2. (PMID:7668837)
- 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: 2/3. (PMID:8554662;PMID:7668837)
- 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: 1/2. (PMID:7668837)
- Chorea (HP:0002072): Chorea (Greek for 'dance') refers to widespread arrhythmic involuntary movements of a forcible, jerky and restless fashion. It is a random-appearing sequence of one or more discrete involuntary movements or movement fragments. Movements appear random because of variability in timing, duration or location. Each movement may have a distinct start and end. However, movements may be strung together and thus may appear to flow randomly from one muscle group to another. Chorea can involve the trunk, neck, face, tongue, and extremities. Evidence: PCS. Frequency: 1/2. (PMID:7668837)
- Mild microcephaly (HP:0040196): Decreased occipito-frontal (head) circumference (OFC). For the microcephaly OFC must be between -3 SD and -2 SD compared to appropriate, age matched, normal standards (i.e. -3 SD <= OFC < -2 SD). Evidence: PCS. Frequency: 1/2. (PMID:7668837)
- Paroxysmal choreoathetosis (HP:0007098): Episodes of choreoathetosis that can occur following triggers such as quick voluntary movements. Evidence: TAS. (OMIM:500003)
- Myoclonus (HP:0001336): Very brief, involuntary random muscular contractions occurring at rest, in response to sensory stimuli, or accompanying voluntary movements. Evidence: PCS. Frequency: 1/2. (PMID:7668837)