- Encephalopathy (HP:0001298): Encephalopathy is a term that means brain disease, damage, or malfunction. In general, encephalopathy is manifested by an altered mental state. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:83600)
- Sleep disturbance (HP:0002360): An abnormal pattern in the quality, quantity, or characteristics of sleep. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:83600)
- Diplopia (HP:0000651): Diplopia is a condition in which a single object is perceived as two images, it is also known as double vision. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Lethargy (HP:0001254): A state of fatigue, either physical or mental slowness and sluggishness, with difficulties in initiating or performing simple tasks. Distinguished from apathy which implies indifference and a lack of desire or interest in the task. A person with lethargy may have the desire, but not the energy to engage in personal or socially relevant tasks. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Mental deterioration (HP:0001268): Loss of previously present mental abilities, generally in adults. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Parkinsonism (HP:0001300): Characteristic neurologic anomaly resulting from degeneration of dopamine-generating cells in the substantia nigra, a region of the midbrain, characterized clinically by shaking, rigidity, slowness of movement and difficulty with walking and gait. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Tremor (HP:0001337): An unintentional, oscillating to-and-fro muscle movement about a joint axis. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Fever (HP:0001945): Body temperature elevated above the normal range. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Headache (HP:0002315): Cephalgia, or pain sensed in various parts of the head, not confined to the area of distribution of any nerve. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Increased CSF protein concentration (HP:0002922): Increased concentration of protein in the cerebrospinal fluid. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Autoimmunity (HP:0002960): The occurrence of an immune reaction against the organism's own cells or tissues. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Myalgia (HP:0003326): Pain in muscle. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Upper limb muscle weakness (HP:0003484): Weakness of the muscles of the arms. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Recurrent viral infections (HP:0004429): Increased susceptibility to viral infections as manifested by recurrent episodes of viral infection. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Limitation of neck motion (HP:0005986). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Bilateral basal ganglia lesions (HP:0007146). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Increased circulating immunoglobulin concentration (HP:0010702): An increased level of gamma globulin (immunoglobulin) in the blood. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Abnormal involuntary eye movements (HP:0012547): Anomalous movements of the eyes that occur without the subject wanting them to happen. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Pharyngitis (HP:0025439): Inflammation (due to infection or irritation) of the pharynx. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Dyskinesia (HP:0100660): A movement disorder which consists of effects including diminished voluntary movements and the presence of involuntary movements. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:83600)
- Urinary incontinence (HP:0000020): Loss of the ability to control the urinary bladder leading to involuntary urination. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:83600)
- Photophobia (HP:0000613): Excessive sensitivity to light with the sensation of discomfort or pain in the eyes due to exposure to bright light. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:83600)
- Psychosis (HP:0000709): A condition characterized by changes in personality and thought patterns, often accompanied by hallucinations and delusional beliefs, is known as psychosis. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:83600)
- 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: TAS. Frequency: Occasional (HP:0040283). (ORPHA:83600)
- Coma (HP:0001259): The complete absence of wakefulness and consciousness, which is evident through a lack of response to any form of external stimuli. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:83600)
- Bradycardia (HP:0001662): A slower than normal heart rate (in adults, slower than 60 beats per minute). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:83600)
- Bowel incontinence (HP:0002607): Involuntary fecal soiling in adults and children who have usually already been toilet trained. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:83600)
- Hyperventilation (HP:0002883): Hyperventilation refers to an increased pulmonary ventilation rate that is faster than necessary for the exchange of gases. Hyperventilation can result from increased frequency of breathing, an increased tidal volume, or both, and leads to an excess intake of oxygen and the blowing off of carbon dioxide. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:83600)
- Limb pain (HP:0009763): Chronic pain in the limbs with no clear focal etiology. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:83600)
- Stiff neck (HP:0025258): A sensation of tightness in the neck when attempting to move it, especially after a period of inactivity. Neck stiffness often involves soreness and difficulty moving the neck, especially when trying to turn the head to the side. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:83600)
These phenotypes are associated with the disease Encephalitis lethargica (ORPHA:83600).