- 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:623615)
- 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: Frequent (HP:0040282). (ORPHA:623615)
- 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- 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:623615)
- Anxiety (HP:0000739): Intense feelings of nervousness, tension, or panic often arise in response to interpersonal stresses. There is worry about the negative effects of past unpleasant experiences and future negative possibilities. Individuals may feel fearful, apprehensive, or threatened by uncertainty, and they may also have fears of falling apart or losing control. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- 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: Frequent (HP:0040282). (ORPHA:623615)
- 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:623615)
- Mental deterioration (HP:0001268): Loss of previously present mental abilities, generally in adults. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- Fever (HP:0001945): Body temperature elevated above the normal range. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- 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:623615)
- Increased CSF protein concentration (HP:0002922): Increased concentration of protein in the cerebrospinal fluid. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- EEG with focal slow activity (HP:0010843): Focal (localized) slow activity reflects focal dysfunction, not diffuse dysfunction (i.e., encephalopathy). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- CSF pleocytosis (HP:0012229): An increased white blood cell count in the cerebrospinal fluid. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- Abnormal brain FDG positron emission tomography (HP:0012658): An anomaly detectable in [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) brain scans. Glucose uptake measured with FDG-PET is a marker of neuronal metabolic activity. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- Short term memory impairment (HP:0033687): A deficit in the retention of pieces of information (memory chunks) for a relatively short time (usually up to 30 seconds). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- Anti-Hu antibody positivity (HP:5000016): The presence of autoantibodies (immunoglobulins) in the blood circulation that react against Hu. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- Anti-LGI1 antibody (HP:5000020): The presence of autoantibodies (immunoglobulins) in the blood circulation that react against leucine-rich glioma-inactivated 1 (LGI1). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- CSF oligoclonal immunoglobulin G bands (HP:6000397): Oligoclonal immunoglobulin G (IgG) bands (OCBs) are a useful diagnostic tool to detect a central humoral response. In particular, cerebrospinal fluid (CSF)-restricted OCBs represent a hallmark of multiple sclerosis (MS). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- EEG with temporal slowing (HP:6001115): Slow-wave activity observed in the temporal area of the scalp electro-encephalogram (EEG). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:623615)
- Paroxysmal vertigo (HP:0010532): Paroxysmal episodes of vertigo. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:623615)
- Anti-CASPR2 (HP:5000005): The presence of autoantibodies (immunoglobulins) in the blood circulation that react against contactin-associated protein-like 2 (CASPR2). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:623615)
- Anti-GABA(B)R antibody (HP:5000010): The presence of autoantibodies (immunoglobulins) in the blood circulation that react against gamma-aminobutyric acid B receptor, i.e., GABA(B)R. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:623615)
These phenotypes are associated with the disease Autoimmune limbic encephalitis (ORPHA:623615).
The following phenotypes are NOT associated with this disease:
- Infectious encephalitis (HP:0002383): A disorder of the brain caused by an infectious agent that presents with fever, headache, and an altered level of consciousness. There may also be focal or multifocal neurologic deficits, and focal or generalized seizure activity. Evidence: TAS. (ORPHA:623615)
- Malignant neoplasm of the central nervous system (HP:0100836): A tumor that originates in the pineal gland, has moderate cellularity and tends to form rosette patterns. Evidence: TAS. (ORPHA:623615)