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HelpOrder Code IEHCG Interference Evaluation Heterophile, Beta-Human Chorionic Gonadotropin, Serum
Ordering Guidance
If "HCG Total OB" or pregnancy is indicated, order THCG / Human Chorionic Gonadotropin (hCG), Quantitative, Pregnancy, Serum.
Specimen Required
Patient Preparation: For 12 hours before specimen collection, do not take multivitamins or dietary supplements containing biotin (vitamin B7), which is commonly found in hair, skin, and nail supplements and multivitamins.
Supplies: Sarstedt Aliquot Tube 5 mL (T914)
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 2.5 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Useful For
Evaluating suspected interference from heterophile antibodies causing a falsely elevated human chorionic gonadotropin result
This test is not to be used for pregnancy testing.
Profile Information
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| HCGII | HCG, Interference Interpretation | No | Yes |
| HCGQN | Beta-HCG, Quantitative, S | Yes, (order BHCG) | Yes |
| HCGAM | HCG, Alternative Method, S | No | Yes |
Testing Algorithm
This heterophile antibody evaluation consists of pretreatment with commercial heterophile antibody blocking reagents, testing on an alternate platform, and serial dilution of the sample.
Method Name
HCGQN: Electrochemiluminescent Immunoassay
HCGAM: Immunoenzymatic Assay
Reporting Name
Interference Eval, Heterophile, HCGSpecimen Type
SerumSpecimen Minimum Volume
1.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Serum | Refrigerated (preferred) | 7 days | |
| Frozen | 90 days | ||
| Ambient | 7 days |
Reject Due To
| Gross hemolysis | Reject |
| Gross lipemia | OK |
| Gross icterus | OK |
Reference Values
BETA-HUMAN CHORIONIC GONADOTROPIN, QUANTITATIVE, SERUM
Children(1,2)
Males
Birth-3 months: ≤50 IU/L*
>3 months-<18 years: <1.4 IU/L
Females
Birth-3 months: ≤50 IU/L*
>3 months-<18 years: <1.0 IU/L
Pediatric reference values based on:
1. Chen RJ, Huang SC, Chow SN, Hsieh CY: Human chorionic gonadotropin pattern in maternal circulation. Amniotic fluid and fetal circulation in late pregnancy. J Reprod Med. 1993;38(2):151-154
2. Schneider DT, Calaminus G, Gobel U: Diagnostic value of alpha 1-fetoprotein and beta-human chorionic gonadotropin in infancy and childhood. Pediatr Hematol Oncol. 2001;18(1):11-26
*Human chorionic gonadotropin (hCG), produced in the placenta, partially passes the placental barrier. Newborn serum beta-hCG concentrations are approximately 1/400th of the corresponding maternal serum concentrations, resulting in neonate beta-hCG levels of 10-50 IU/L at birth. Clearance half-life is approximately 2 to 3 days. Therefore, by 3 months of age, levels comparable to adults should be reached.
Adults (97.5th percentile)
Males: <1.4 IU/L
Females
Premenopausal, nonpregnant: <1.0 IU/L
Postmenopausal: <7.0 IU/L
HUMAN CHORIONIC GONADOTROPIN, ALTERNATIVE METHOD
Males
Birth-3 months: Not established
>3 months-49 years: <0.6 IU/L
50 years-80 years: <1.6 IU/L
>80 years: Not established
Females
Birth-3 months: Not established
>3 months-40 years: <0.6 IU/L
41 years-50 years: <6.2 IU/L
51 years-150 years: <7.8 IU/L
Method Description
The specimen will be evaluated for potential heterophile antibody interference in the Roche Elecsys total beta-human chorionic gonadotropin (hCG) immunoassay. Heterophile Antibody evaluation will consist of pretreatment with commercial heterophile antibody blocking reagents, testing on an alternate platform (Beckman Coulter), and serial dilution of the sample.
Heterophile blocking agents consisted of heterophile blocking tube (HBT)-Scantibodies Inc. for the Roche assay and heterophile blocking agent (HBR)-Scantibodies, Inc. for the Beckman assay. These blockers contain either murine- (HBT) or goat- (HBR) derived proteins in a buffered salt solution.
Beta-hCG, Quantitative, Serum
The Roche hCG assay is a 2-site immunometric sandwich assay using electrochemiluminescence detection. Patient specimen, biotinylated monoclonal hCG-specific antibody, and monoclonal hCG-specific antibody labeled with a ruthenium react to form a complex. Streptavidin-coated microparticles act as the solid phase to which the complex becomes bound. Voltage is applied to the electrode inducing a chemiluminescent emission from the ruthenium, which is then measured against a calibration curve to determine the amount of hCG in the patient specimen.(Package insert:Â hCG. Roche Diagnostics; V1.0 10/2020)
HCG, Alternative Method
The Access Total beta hCG (5th IS) assay is a sequential two-step immunoenzymatic (“sandwich") assay. A sample is added to a reaction vessel along with a citrate buffer. After an initial incubation, rabbit anti-beta hCG alkaline phosphatase conjugate and paramagnetic particles coated with goat anti-mouse IgG: mouse monoclonal anti-beta hCG complexes are added. The hCG binds to the immobilized monoclonal anti-beta hCG on the solid phase while, at the same time, the rabbit anti-beta hCG alkaline phosphatase conjugate reacts with different antigenic sites on the hCG. After incubation in a reaction vessel, materials bound to the solid phase are held in a magnetic field while unbound materials are washed away. Then, the chemiluminescent substrate Lumi-Phos* 530 is added to the vessel, and the light generated by the reaction is measured with a luminometer. The light production is directly proportional to the concentration of total beta hCG in the sample. The amount of analyte in the sample is determined from a stored, multi-point calibration curve.(Instruction manual: Access Total beta hCG 5th IS. Beckman Coulter Inc; 2020)
Day(s) Performed
Monday through Saturday
Performing Laboratory
Mayo Clinic Laboratories in Rochester
CPT Code Information
84702 x 2