MedGen

A rare autoimmune encephalitis involving the mesial temporal lobes and clinically characterized by subacute onset (rapid progression of less than three months) of short-term memory deficits, seizures or psychiatric symptoms, such as behavioral changes, anxiety, depression, and psychosis. Further diagnostic criteria are bilateral abnormalities restricted to the mesial temporal lobes in brain MRI, cerebrospinal fluid pleocytosis and/or epileptic or slow-wave activity involving the temporal lobes in EEG, and reasonable exclusion of alternative causes. Paraneoplastic or non-paraneoplastic antibodies against neuronal antigens may be found in serum and/or cerebrospinal fluid. [from SNOMEDCT_US]

A disorder that results from a chromosomal abnormality. [from NCI]

A chromosomal abnormality consisting of the presence of one chromosome in addition to the normal diploid number. [from NCI]

Down syndrome, the most frequent form of mental retardation caused by a microscopically demonstrable chromosomal aberration, is characterized by well-defined and distinctive phenotypic features and natural history. It is caused by triplicate state (trisomy) of all or a critical portion of chromosome 21. [from OMIM]