Paired Helical Filament-Tau (PHF-Tau) by Immunohistochemistry

Casandra

Casandra Test Code AR01906Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 2004094CPT Code 88342

Paired Helical Filament-Tau (PHF-Tau) by Immunohistochemistry

Also known as: PHFTAU IHC

Clinical Use

Order Test

Use

The Paired Helical Filament-Tau (PHF-Tau) by Immunohistochemistry test is used to detect the presence of PHF-Tau protein in tissue samples. This protein is associated with neurofibrillary tangles found in the brains of patients with Alzheimer's disease and other neurodegenerative disorders. The test can help in the differential diagnosis of tauopathies and other related conditions by identifying the accumulation of this specific tau protein.

Special Instructions

This test requires submission through an electronic request. If electronic ordering is unavailable, the ARUP Immunohistochemistry Stain Form (#32978) should be used along with an ARUP client number. For additional technical details, contact ARUP Client Services at (800) 522-2787.

Limitations

This test is performed as a technical service only, meaning it returns stained slides for pathology interpretation but does not provide an interpretive report. As an immunohistochemistry assay, the results can be affected by the quality and handling of the tissue sample, including fixation and processing methods. The specificity of staining is subject to potential cross-reactivity with other proteins, which may lead to false positives or negatives. Additionally, results should be interpreted in conjunction with clinical and other diagnostic findings.

Test Details

New York Approved

Methodology

Immunoassay (IHC)

Biomarkers

PHF-Tau

Protein

IHC • Expression • Categorical (e.g., Positive / Negative / Indeterminate)

LOINC Codes

Result Codes

94736-6

Result Turnaround Time

1-3 days

Specimen

Tissue (FFPE)

Volume

Not provided

Minimum Volume

2 slides

Container

tissue transport kit (ARUP supply #47808)

Collection Instructions

Formalin fix (10 percent neutral buffered formalin) and paraffin embed specimen (cells must be prepared into a cellblock). Protect paraffin block and/or slides from excessive heat. Transport tissue block or 5 unstained (3- to 5-micron thick sections), positively charged slides.