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ข้อมูลทั่วไป Specimen
ข้อมูลสิ่งส่งตรวจ Performance
ข้อมูลการทดสอบ Clinical & Interpretation
ข้อมูลทางคลินิก

Test Code (รหัสการทดสอบ):

090-21-2002 Change methodology (Kritnarong)

Order Name (ชื่อการทดสอบ):

p-tau217 (Plasma phosphorylated-tau 217) **

Specimen / Container (สิ่งส่งตรวจ/ภาชนะ):

Blood/ K3 EDTA (Lavender Top) 6 mL, 2 tubes

Turnaround Time (ระยะเวลารอผล):

14 official days

Useful For (ประโยชน์การทดสอบ):

Evaluation of individuals, aged 50 years and older, presenting with cognitive impairment who are being assessed for Alzheimer disease and other causes of cognitive decline.

This test is not intended as a screening test for Alzheimer disease in asymptomatic individuals.

Methodology (วิธีการทดสอบ):

Chemiluminescent Enzyme Immunoassay (CLEIA)

Test Code (รหัสการทดสอบ):

090-21-2002 Change methodology (Kritnarong)

Order Name (ชื่อการทดสอบ):

p-tau217 (Plasma phosphorylated-tau 217) **

Collection Specimen Or Container (สิ่งส่งตรวจ/ภาชนะ):

Blood/ K3 EDTA (Lavender Top) 6 mL, 2 tubes

Specimen Testing Type (สิ่งส่งตรวจที่ใช้ในการทดสอบ):

EDTA Plasma, minimum volume 2 mL

Rejection Criteria (เกณฑ์ปฏิเสธสิ่งส่งตรวจ):

Gross hemolysis Reject
Gross lipemia OK
Gross icterus OK

Specimen Stabillity (ความคงตัวของสิ่งส่งตรวจ):

Specimen type	Temperature	Time
EDTA Plasma	Refrigerated (preferred)	14 days
	Ambiebt	72 hours
	Frozen	90 days

Test Code (รหัสการทดสอบ):

090-21-2002 Change methodology (Kritnarong)

Order Name (ชื่อการทดสอบ):

p-tau217 (Plasma phosphorylated-tau 217) **

Schedule (ตารางการทดสอบ):

N/A **Sent Out to MAYO, USA

Turnaround Time (ระยะเวลารอผล):

14 official days

Performing Location (หน่วยงานที่ทำการทดสอบ):

MAYO Laboratory
Referral Lab Services, Laboratory Department 14187, 14162

Test Code (รหัสการทดสอบ):

090-21-2002 Change methodology (Kritnarong)

Order Name (ชื่อการทดสอบ):

p-tau217 (Plasma phosphorylated-tau 217) **

Reference Value (ค่าอ้างอิง):

Negative: ≤0.185 pg/mL
Intermediate: 0.186 – 0.324 pg/mL;
Positive: ≥0.325 pg/mL

Interpretation (การแปลผล):

Negative: A normal (negative) phosphorylated Tau217 (p-Tau217) result is consistent with a negative (normal) amyloid-positron emission tomography (PET) scan result. This result indicates a reduced likelihood that an individual has neuropathological changes associated with Alzheimer disease.

Intermediate: An intermediate p-Tau217 result cannot accurately differentiate between the presence or absence of neuropathological changes associated with Alzheimer disease. Further testing, such as amyloid-positron emission tomography (PET) or cerebrospinal fluid Abeta42 and tau biomarkers, is needed to determine the likelihood of neuropathological changes associated with Alzheimer disease being present.

Positive: An elevated (positive) p-Tau217 result is consistent with a positive (abnormal) amyloid-positron emission tomography (PET) scan result. This result is consistent with the presence of neuropathological changes associated with Alzheimer disease. In the proper clinical context this test is supportive of Alzheimer disease being related to current clinical symptoms. This test has not been demonstrated to provide information on the risk of an asymptomatic individual developing symptoms related to Alzheimer disease in the future.

Clinical performance of this test was established in a study of 427 individuals aged 50 years and older with mild cognitive impairment or early dementia with a 64% prevalence of amyloid pathology defined by an amyloid-PET and a Centiloid scale value of 25 or more. For detection of an abnormal amyloid-PET, pTau217 test sensitivity at the lower cutpoint (< or =0.185 pg/mL) was 92% and the specificity at the upper cutpoint (> or =0.325 pg/mL) was 96%. The diagnostic performance of this test has not been established in asymptomatic individuals.

Clinical Reference (เอกสารอ้างอิง):

PT217 - Overview: Phospho-Tau 217, Plasma (mayocliniclabs.com) (Retrieved: 23 Jan 2026)