P Tau 217 Score Variability

Alzsymptoms

I had a P Tau 217 test score of .2 in November 2025. Anything over .18 was considered positive. I then had a PET scan with a centiloid score of 46. In late May 2026 I participated in a research trial with Care Access and received a P Tau 217 score of .47, with anything over .18 considered positive. I am very concerned about the rapid increase in the P Tau score, but my neurologist said not to worry about it because there is a great deal of variability in scores with P Tau testing. She doesn't want to start me on any anti-amyloid treatments, but I don't want to get worse and miss the short window to start the treatments. Has anyone heard this before? Should I get a second opinion? Thanks!

Dneige89

Hello. Something to consider is whether or not the PTau test was performed by the same lab each time. This is a big jump so I would consider having another PTau test at the same lab you had the first one. I wish you all the best🤗

Alzsymptoms

Thanks so much! Using the same lab for testing is a great idea.