- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: PCS. Frequency: 1/1. (PMID:26216125)
- 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: PCS. Frequency: 1/2. (PMID:26216125)
- CSF lymphocytic pleiocytosis (HP:0200149): An increased lymphocyte count in the cerebrospinal fluid. Evidence: PCS. Frequency: 1/1. (PMID:26216125)
- Nuchal rigidity (HP:0031179): Resistance of the extensor muscles of the neck to being bent forwards (i.e., impaired neck flexion) as a result of muscle spasm of the extensor muscles of the neck. Nuchal rigidity is not a fixed rigidity. Nuchal rigidity has been used as a bedside test for meningism, although its sensitivity for this purpose has been debated. Evidence: PCS. Frequency: 1/2. (PMID:26216125)
- 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:26216125)
- HSV encephalitis (HP:0012302): Infection of the brain parenchyma with herpes simplex virus, resulting in inflammation of the brain parenchyma with neurologic dysfunction. Evidence: PCS. Frequency: 1/2. (PMID:26216125)
- Autosomal dominant inheritance (HP:0000006): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in heterozygotes. In the context of medical genetics, an autosomal dominant disorder is caused when a single copy of the mutant allele is present. Males and females are affected equally, and can both transmit the disorder with a risk of 50% for each child of inheriting the mutant allele. Evidence: PCS. (PMID:26216125)
These phenotypes are associated with the disease herpes simplex encephalitis, susceptibility to, 7 (OMIM:616532).