- Abnormal saccadic eye movements (HP:0000570): An abnormality of eye movement characterized by impairment of fast (saccadic) eye movements. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:1183)
- 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: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:1183)
- Myoclonus (HP:0001336): Very brief, involuntary random muscular contractions occurring at rest, in response to sensory stimuli, or accompanying voluntary movements. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:1183)
- Sleep disturbance (HP:0002360): An abnormal pattern in the quality, quantity, or characteristics of sleep. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:1183)
- Opsoclonus (HP:0010543): Bursts of large-amplitude multidirectional saccades without intersaccadic interval. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:1183)
- Atypical behavior (HP:0000708): Atypical behavior is an abnormality in a person's actions that can be controlled or modulated by the will of the individual. While abnormal behaviors can be difficult to control, they are distinct from other abnormal actions that cannot be affected by the individual's will. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:1183)
- Irritability (HP:0000737): An emotional state characterized by negative feelings of heightened frustration, annoyance, or feeling upset, often triggered by internal factors (e.g., fatigue, hunger, unfulfilled desires) or external factors (e.g., social or environmental challenges). Irritability may be unpredictable, and is accompanied by a lowered threshold for emotional reactivity and observable features (speech, facial expressions, or psychomotor activity). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:1183)
- Vertigo (HP:0002321): An abnormal sensation of spinning while the body is actually stationary. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:1183)
- Neoplasm (HP:0002664): An organ or organ-system abnormality that consists of uncontrolled autonomous cell-proliferation which can occur in any part of the body as a benign or malignant neoplasm (tumor). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:1183)
- Neuroblastoma (HP:0003006): Neuroblastoma is a solid tumor that originate in neural crest cells of the sympathetic nervous system. Most neuroblastomas originate in the abdomen, and most abdominal neuroblastomas originate in the adrenal gland. Neuroblastomas can also originate in the thorax, usually in the posterior mediastinum. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:1183)
- Limb myoclonus (HP:0045084). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:1183)
- Cognitive impairment (HP:0100543): Abnormal cognition is characterized by deficits in thinking, reasoning, or remembering. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:1183)
- Anti-Amphiphysin antibody (HP:5000002): The presence of autoantibodies (immunoglobulins) in the blood circulation that react against Amphiphysin. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:1183)
- 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: Occasional (HP:0040283). (ORPHA:1183)
- Rigidity (HP:0002063): Continuous involuntary sustained muscle contraction. When an affected muscle is passively stretched, the degree of resistance remains constant regardless of the rate at which the muscle is stretched. This feature helps to distinguish rigidity from muscle spasticity. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:1183)
- Melanoma (HP:0002861): The presence of a melanoma, a malignant cancer originating from pigment producing melanocytes. Melanoma can originate from the skin or the pigmented layers of the eye (the uvea). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:1183)
- Breast carcinoma (HP:0003002): The presence of a carcinoma of the breast. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:1183)
- Ovarian teratoma (HP:0012226): The presence of a teratoma in the ovary. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:1183)
- Autoimmune antibody positivity (HP:0030057): The presence of an antibody in the blood circulation that is directed against the organism's own cells or tissues. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:1183)
- Small cell lung carcinoma (HP:0030357): Small cell lung cancer (SCLC) is a type of highly malignant lung cancer that is composed of small ovoid cells. In the past, SCLC was called oat cell carcinoma because the microscopic appearance of the cells was felt to resemble oats. SLCLC usually originates near the bronchi and in many cases may grow and metastasize quickly. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:1183)
- Chronic infection (HP:0031035): Presence of a protracted or persistent infection by a pathogen potentially related to an underlying abnormality of the immune system that is not able to clear the infection. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:1183)
- Neoplasm of the lung (HP:0100526): Tumor of the lung. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:1183)
These phenotypes are associated with the disease Opsoclonus-myoclonus syndrome (ORPHA:1183).