ATN Profile, Plasma

ATN Profile, Amyloid-Tau-Neurodegeneration Profile

Up to 7 days

(High Sensitivity) Chemiluminescent Enzyme Immunoassay

The plasma ATN (Amyloid–Tau–Neurodegeneration) profile, as described by the Alzheimer’s Association and National Institute of Aging in the 2024 guidelines, offers a practical framework to characterizing Alzheimer’s disease (AD) pathology using the fluid biomarkers; amyloid-beta 42/40 ratio, phosphorylated tau-217 (p-Tau 217) and neurofilament light chain (NfL). A decrease in the cerebrospinal fluid (CSF) and, to a lesser extent plasma amyloid-beta 42/40 ratio reflects cerebral amyloid plaque deposition. CSF and plasma p-Tau 217, at lower levels reflects amyloid burden and, at higher levels, tau tangle formation. NfL serves as a marker of axonal injury and neurodegeneration. Both retrospective and prospective clinical trials have demonstrated correlations between plasma and CSF concentrations of these biomarkers, as well as to amyloid or tau PET imaging, for distinguishing Alzheimer’s disease from other causes of dementia and cognitive decline. The most common indications for measurement of the ATN profile include:

•Early evaluation of cognitive decline, differential diagnosis of dementia and screening prior to confirmatory testing.
•Monitoring disease progression: to track biomarker changes longitudinally in patients with confirmed Alzheimer’s disease, providing insight into disease trajectory; the most-reliable biomarker is p-Tau 217.
•Assessing response to therapy: To evaluate treatment effects during disease-modifying therapy, where reductions in p-Tau 217 can be expected.

Accredited NRL Laboratory

Weekly

The plasma ATN (Amyloid–Tau–Neurodegeneration) profile, as described by the Alzheimer’s Association and National Institute of Aging in the 2024 guidelines, offers a practical framework to characterizing Alzheimer’s disease (AD) pathology using the fluid biomarkers; amyloid-beta 42/40 ratio, phosphorylated tau-217 (p-Tau 217) and neurofilament light chain (NfL).

K2-EDTA Plasma

Minimum 2 mL

K2-EDTA Plasma (Lavender Top)

Samples should be collected following overnight fasting. If patients are taking biotin (Vitamin B7), they should stop taking it 72 hours prior to sample collection.

IMPORTANT: ATN plasma samples are very unstable, and, for optimum results, samples should be immediately centrifuged in a refrigerated centrifuge, aliquoted and transported to NRL frozen (–20°C). If aliquoting and freezing is not possible, refrigerated samples must be received at NRL within 6 hours of collection. Refrigerated samples received beyond this time will be rejected.