Days Set Up
Monday - Friday
Analytic Time

8 hours

MiChart Code

Test Updated:


Heterophile AB Interferent Scr
Heterophile Interference Screen
Heterophile Ab
Heterophilic Antibody
Heterophile Antibody Screen
Heterophilic Blocking Tube (HBT)

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Test Overview

Test Methodology

Sandwich immunoassay with Heterophile Blocking Tube (HBT) pretreatment

Test Usage

A heterophilic sample is a serum or plasma sample containing antibodies which are able to bind to animal antibodies used in immunochemistry assays. The most commonly reported assay interference effect of heterophilic antibodies is a false positive assay result. The Heterophilic Blocking Tube (HBT) allows for the elimination of false positive heterophilic interference in serum or plasma for sandwich immunoassays (e.g., FSH, LH, Prolactin, TSH, Ferritin, CEA, AFP, BHcG, CKMB, CA125 and CA19-9). HBT is a sample pretreatment/second assay intended to confirm or disqualify the original non pretreatment assay result. If the pretreatment result is the same as the original non treated result, the immunochemistry is not affected by a heterophilic antibody interferent in the patient's sample. If the pretreatment sample is lower than the original result, the sample may contain heterophile antibodies affecting the immunoassay and the original result will not be reported.

Reference Range

No heterophilic antibody interference detected.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Yellow Top Tube
Normal Volume
1 mL serum or plasma
Minimum Volume
0.5 mL serum or plasma

Billing Information

CPT Code
Pro Fee Code

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.