CSF Panel for Prion Markers | Pathology | School of Medicine

14-3-3γ (ELISA), Total TAU (ELISA) and RT-QuIC for Prion Proteins
CPT Code	86317 (14-3-3 & TAU), 0035U (RT-QuIC)
Ordering Recommendation	May aid in the diagnosis of prion disease. RT-QuIC identifies the disease-causing agent. Total TAU and 14-3-3γ are indirect markers of neurodegenerative diseases. Assumes that the patient has a history of a rapid neurodegenerative condition and does not have several conditionsⁱ that might compromise the test results.
Methodology	Quantitative Enzyme-Linked Immunosorbent Assay (ELISA). Real-Time Quaking-Induced Conversion (RT-QuIC)ⁱⁱ.
Available STAT	No.
Analytic Timeⁱⁱⁱ	7 business days.
New York DOH Approval Status	This panel is New York DOH-approved.
Submit With Order	NPDPSC Test Request Form

Specimen Requirements
Patient preparation	The patient must be 12 years of age or older.
Specimen Type	Cerebrospinal Fluid (CSF) obtained by lumbar puncture.
Required Container	Cerebrospinal Fluid kit tubes, or Polypropylene transfer tubes.
Specimen Preparation	The first 2ml of CSF that flows from the tap should be discarded. Collect 2 ml of CSF (1 ml minimum), avoiding bloody tap. The sample must be immediately frozen, at least in a -20°C freezer.
Storage/Transport Temperature	Frozen. Shipping transport on dry ice.^iv. Please note: shipments are not received on weekends and/or holidays. Ship only Monday through Thursday (priority overnight).
Unacceptable Conditions	Bloody and insufficient sample quantity.
Remarks	Complete the required test request form linked above.
Stability	Freeze CSF at -20°C immediately after collection.

Specimen Reporting
Critical Results	None.
Reference Range(s)	RT-QuIC: Negative Total TAU (ELISA): 0-1149 pg/mL 14-3-3 GAMMA (ELISA): <173 - 1999 AU/mL.
Likelihood of Prion Disease	RT-QuIC Positive: >98% RT-QuIC Negative & Total TAU <499 = <0.2% RT-QuIC Negative & Total TAU 500-2499 = <1%

References

i. Conditions include but are not limited to, subarachnoid hemorrhage, various encephalitis, stroke with acute infarction, multi-infarct dementia with acute infarction, brain neoplasm, and paraenoplastic neurological disorders. These conditions may yield false-positive results.
ii. CSF RT-QuIC has a diagnostic sensitivity and specificity of 90.3% and 98.5%, respectively (Rhoads DD, Neurology 2020).
iii. Expected turnaround time (business days) for results, beginning when the center receives the specimen.
iv. A recent re-evaluation of the shipment conditions of CSF specimens showed that shipment at room temperature caused a decrease in the accuracy of RT-QuIC, 14-3-3 protein, and TAU protein assays when compared with the shipment of frozen CSF samples on dry ice.