- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: PCS. Frequency: 4/40. (PMID:39468830)
- Decreased motor nerve conduction velocity (HP:0003431): A type of decreased nerve conduction velocity that affects the motor neuron. Evidence: PCS. Frequency: 9/9. (PMID:39468830)
- Hearing impairment (HP:0000365): A decreased magnitude of the sensory perception of sound. Evidence: PCS. Frequency: 0/2. (PMID:39468830)
- Decreased number of large peripheral myelinated nerve fibers (HP:0003387): A reduced number of large myelinated nerve fibers. Evidence: PCS. Frequency: 0/2. (PMID:39468830)
- 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: 10/10. (PMID:39468830)
- Gait disturbance (HP:0001288): The term gait disturbance can refer to any disruption of the ability to walk. Evidence: PCS. Frequency: 10/10. (PMID:39468830)
- Abnormal fundus morphology (HP:0001098): Any structural abnormality of the fundus of the eye. Evidence: PCS. Frequency: 0/2. (PMID:39468830)
- Hoffmann sign (HP:0031993): A Hoffmann test is performed by flicking the fingernail of the long finger, from dorsal to volar, on each hand while the hand was supported by the examiner's hand. The test was done with the neck in the neutral position and then with the neck maximally forward flexed. Any flexion of the ipsilateral thumb and/or index finger was interpreted as a positive test. Evidence: PCS. Frequency: 7/10. (PMID:39468830)
- Hyperactive Achilles reflex (HP:0033206): Increased intensity of the Achilles reflex. Evidence: PCS. Frequency: 10/10. (PMID:39468830)
- Knee clonus (HP:0011449): Clonus is an involuntary tendon reflex that causes repeated flexion and extension of the foot. Knee clonus can be tested by rapidly pushing the patella towards the toes. Evidence: PCS. Frequency: 2/10. (PMID:39468830)
- Ankle clonus (HP:0011448): Clonus is an involuntary tendon reflex that causes repeated flexion and extension of the foot. Ankle clonus is tested by rapidly flexing the foot upward. Evidence: PCS. Frequency: 7/10. (PMID:39468830)
- Motor conduction block (HP:0012078): Blockade of impulses at a focal site along the course of a motor axon. Evidence: PCS. Frequency: 9/9. (PMID:39468830)
- Hyperactive patellar reflex (HP:0007083). Evidence: PCS. Frequency: 10/10. (PMID:39468830)
- Lower limb muscle weakness (HP:0007340): Weakness of the muscles of the legs. Evidence: PCS. Frequency: 7/10. (PMID:39468830)
- Abnormality of visual evoked potentials (HP:0000649): An anomaly of visually evoked potentials (VEP), which are electrical potentials, initiated by brief visual stimuli, which are recorded from the scalp overlying the visual cortex. Evidence: PCS. Frequency: 0/2. (PMID:39468830)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 2/10. (PMID:39468830)
- Young adult onset (HP:0011462): Onset of disease at the age of between 16 and 40 years. Evidence: PCS. Frequency: 4/40. (PMID:39468830)
- 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:39468830)
- Spastic paraplegia (HP:0001258): Complete loss of the ability to move the lower limbs accompanied by spasticity of the lower limbs. Evidence: PCS. Frequency: 10/10. (PMID:39468830)
- Decreased sensory nerve conduction velocity (HP:0003448): Reduced speed of conduction of the action potential along a sensory nerve. Evidence: PCS. Frequency: 9/9. (PMID:39468830)
- Impaired distal vibration sensation (HP:0006886): A decrease in the ability to perceive vibration in the distal portions of the limbs. Evidence: PCS. Frequency: 8/10. (PMID:39468830)
These phenotypes are associated with the disease spastic paraplegia, mitochondrial (OMIM:500018).