Skin Test for Alzheimer’s Studied

A skin test for Alzheimer’s disease that is accurate within the first two years of the disease’s progression has moved a step closer.

The test — currently in clinical trials — can be performed in a doctor’s office or outpatient clinic by a nurse or medical technician, and could also be adapted to work in blood samples.

Because recent research has discovered evidence of Alzheimer’s disease throughout the body as well as the brain, researchers Daniel Alkon and Tapan Khan, of the Blanchette Rockefeller Neurosciences Institute sought to develop a test for Alzheimer’s-related inflammation in skin cells called fibroblasts.

Alzheimer’s disease stimulates changes in a fibroblast enzyme called MAP Kinase Erk 1/2 that produce a distinct response to an amino acid called bradykinin.

Similar responses were noted in patients with Parkinson’s disease, multiple infarct dementia (dementia caused by small strokes), and Huntington’s chorea, and the test was also accurate when performed on skin cells from patients with autopsy-confirmed Alzheimer’s.

Alkon said he thought the measure would have great clinical utility.

When it begins, Alzheimer’s disease is often difficult to distinguish from other dementias or mild cognitive impairment, Alkon said. Potential treatments of Alzheimer’s, however, are likely to have their greatest efficacy before the devastating and widespread impairment of brain function that inevitably develops after four or more years.

The research appears in the August 14 issue of the Proceedings of the National Academies of Science.