Dementia with Lewy bodies (DLB) is the second most common type of neurodegenerative dementia after Alzheimer’s disease. It is associated with characteristic features such as the symptoms of Parkinson’s disease, visual hallucinations and fluctuating cognitive impairment. The diagnosis of DLB can be difficult. Currently there is a scan that helps to diagnose DLB, but it is negative in around 1 in 5 people who have DLB. In the earliest stages of the disease, this scan may be less useful.
DLB and Parkinson’s disease (PD) are part of a group of illnesses called Lewy body disorders. These are caused by deposition of a protein called α-synuclein in the brain. α-synuclein is also found in other parts of the body, such as the nerves in the skin and gut.
Identifying α-synuclein in areas outside the brain may help in the diagnosis of DLB and PD. Earlier diagnosis could be possible because α-synuclein may be present in these areas before it is present in the brain. A recent study used a new technique to reliably identify α-synuclein in the skin of people with PD using a test called punch biopsy. The punch biopsy has been described as a safe and minimally invasive technique by the European Federation of Neurological Societies.
The Punch Biopsy
The sample is taken from arm or leg.
A local anaesthetic is used to numb the skin. This stings a bit, but the skin should then be numb for the procedure.
A small sample is taken as shown in the diagram. The actual width of the sample taken is the same as this dot:
A single suture may be inserted at the site. This will be removed a few days later by the study team.
We would like to test if α-synuclein can be found in the skin of people with DLB. If α-synuclein is found to be present in DLB, punch biopsies may be a useful tool in the diagnosis of DLB, particularly in the earliest stages of the disease.
Participants will already have a diagnosis of DLB or AD or will be healthy control subjects. The procedure will not benefit them directly. The aim of the study is to see if punch biopsies could be used to help diagnose DLB in the future.
α-Synuclein biopsy project
Professor of Old Age Psychiatry
University of Newcastle