AIDS dementia

HIV itself affects the brain. Glia cells are infected. HIV causes progressive behavioural, short-term memory and concentration disorders. These develop over the course of several months into presenile dementia with retention of consciousness. Aphasia, alexia and agraphia are usually absent (in contrast to Alzheimer’s disease), though motor abnormalities frequently occur, with unstable gait and a feeling of weakness in the legs. The tendon reflexes are increased. The patient becomes forgetful, can concentrate only with difficulty, quickly loses the thread of a conversation or has to read a text repeatedly in order to understand it. He/she becomes clumsy, suffers from tremor, his/her handwriting becomes blurred (coordination problems) and the sense of balance can become somewhat disturbed, especially when the patient quickly turns his/her head. Awareness of the disease is retained for quite a long time and the patient can describe the symptoms well. Apathy occurs later and the patient becomes mentally retarded. The cerebrospinal fluid often contains a large number of cells, an increased protein level and a discretely reduced glucose level. Agitation, confusion, hallucinations and psychosis can occur. Pyramidal symptoms such as spasticity, hyperreflexia, clonus and the presence of Babinski's sign can occur late. Incontinence also occurs late.

One of the most feared consequences of HIV is AIDS-related dementia. The same genetic mutation (epsilon-4 mutation of apolipoprotein E) that increases the risk for Alzheimer's dementia in HIV negative elderly persons may place HIV positive persons at higher risk for AIDS-related dementia (AIDS dementia complex) and peripheral neuropathy. Larger trials are needed to confirm these results.