- Cerebral amyloid angiopathy (HP:0011970): Amyloid deposition in the walls of leptomeningeal and cortical arteries, arterioles, and less often capillaries and veins of the central nervous system. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:85458)
- 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:85458)
- Cerebral hemorrhage (HP:0001342): Hemorrhage into the parenchyma of the brain. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:85458)
- Cerebral cortical atrophy (HP:0002120): Atrophy of the cortex of the cerebrum. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:85458)
- Subarachnoid hemorrhage (HP:0002138): Hemorrhage occurring between the arachnoid mater and the pia mater. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:85458)
- 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:85458)
- Progressive neurologic deterioration (HP:0002344). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:85458)
- Dilation of Virchow-Robin spaces (HP:0012520): Increased dimensions of the Virchow-Robin spaces (also known as perivascular spaces), which surround the walls of vessels as they course from the subarachnoid space through the brain parenchyma. Perivascular spaces are commonly microscopic, and not visible on conventional neuroimaging. This term refers to an increase of size of these spaces such that they are visible on neuroimaging (usually magnetic resonance imaging). The dilatations are regular cavities that always contain a patent artery. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:85458)
- Dementia (HP:0000726): A loss of global cognitive ability of sufficient amount to interfere with normal social or occupational function. Dementia represents a loss of previously present cognitive abilities, generally in adults, and can affect memory, thinking, language, judgment, and behavior. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:85458)
- Increased CSF protein concentration (HP:0002922): Increased concentration of protein in the cerebrospinal fluid. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:85458)
- CSF pleocytosis (HP:0012229): An increased white blood cell count in the cerebrospinal fluid. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:85458)
- Cerebral cortical microinfarct (HP:0025714): An infarct located on the outer layer of the cerebrum that can only be observed microscopically. Cerebral microinfarcts are typically defined as sharply delimited microscopic regions of cellular death or tissue necrosis, sometimes with cavitation (that is, a central fluid-filled cavity). The term microscopic denotes that these lesions are not visible by gross inspection of the brain but seen by light microscopy. The term infarct is most commonly used for ischemia-related tissue loss, and indeed the pathologic appearance of microinfarcts is consistent with that of known ischemic infarctions. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:85458)
- Hyperintensity of cerebral white matter on MRI (HP:0030890): A brighter than expected signal on magnetic resonance imaging emanating from the cerebral white matter. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:85458)
These phenotypes are associated with the disease Hereditary cerebral amyloid angiopathy (ORPHA:85458).