IMMULITE 2000 Thyroglobulin is a two-site chemiluminescent immunometric assay for use with the IMMULITE 2000 Analyzer and designed for the quantitative measurement of thyroglobulin in serum or heparinized plasma. It is intended strictly for in vitro diagnostic use as an aid in monitoring patients who have undergone thyroidectomy.
Device Story
IMMULITE 2000 Thyroglobulin is an automated in vitro diagnostic assay for measuring thyroglobulin levels in serum or heparinized plasma. Used with the IMMULITE 2000 Analyzer, the device employs a two-site chemiluminescent immunometric principle. Patient samples are incubated with ligand-labeled anti-thyroglobulin monoclonal antibodies and alkaline phosphatase-labeled anti-thyroglobulin polyclonal antibodies. The resulting antibody-thyroglobulin sandwich complex binds to an anti-ligand-coated solid phase bead. After centrifugal washing, a phosphate ester of adamantyl dioxetane substrate is added. Alkaline phosphatase hydrolyzes the substrate, producing sustained light emission measured by a luminometer. Photon output is proportional to thyroglobulin concentration. The system is operated by laboratory personnel in clinical settings. Results assist clinicians in monitoring patients post-thyroidectomy and in the differential diagnosis of congenital hypothyroidism by identifying functioning thyroid tissue presence or changes relative to baseline.
Clinical Evidence
Method comparison study using 150 clinical samples (Hashimoto's disease, Graves disease, post-thyroidectomy, and euthyroid individuals). Compared IMMULITE 2000 against ORGenTec Thyroglobulin ELISA (Kit A). Results: 93.3% agreement, 100% sensitivity (95% CI: 69.2%–100%), and 92.9% specificity (95% CI: 87.3%–96.5%). Linear regression analysis yielded IMMULITE 2000 = 2.29 × Kit A + 0.05 ng/mL (r = 0.95).
Technological Characteristics
Chemiluminescent enzyme-labeled immunometric assay. Components: ligand-labeled monoclonal antibody, alkaline phosphatase-labeled polyclonal antibody, anti-ligand-coated solid phase bead. Detection: phosphate ester of adamantyl dioxetane substrate. Energy source: electrical (automated analyzer). Form factor: reagent system for use with IMMULITE 2000 Analyzer. Connectivity: automated system. Sterilization: not applicable (reagent kit).
Indications for Use
Indicated for the quantitative measurement of thyroglobulin in serum or heparinized plasma as an aid in monitoring patients who have undergone thyroidectomy.
Regulatory Classification
Identification
A tumor-associated antigen immunological test system is a device that consists of reagents used to qualitatively or quantitatively measure, by immunochemical techniques, tumor-associated antigens in serum, plasma, urine, or other body fluids. This device is intended as an aid in monitoring patients for disease progress or response to therapy or for the detection of recurrent or residual disease.
Special Controls
*Classification.* Class II (special controls). Tumor markers must comply with the following special controls: (1) A guidance document entitled “Guidance Document for the Submission of Tumor Associated Antigen Premarket Notifications (510(k)s) to FDA,” and (2) voluntary assay performance standards issued by the National Committee on Clinical Laboratory Standards.
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3/12/99
K982468
# 510(k) Summary Safety and Effectiveness
This summary of safety and effectiveness information has been prepared in accordance with the requirements of SMDA 1990 and 21 CFR Part 807.92.
| Name:<br>Address: | Diagnostic Products Corporation<br>5700 West 96th Street<br>Los Angeles, California 90045-5597 | | |
|-----------------------------------------------|-------------------------------------------------------------------------------------------------------------------------|--|--|
| Telephone Number:<br>Facsimile Number: | (310) 645-8200<br>(310) 645-9999 | | |
| Contact Person: | Edward M. Levine, Ph.D.<br>Director of Clinical Affairs | | |
| Date of Preparation: | February 12, 1999 | | |
| Device Name:<br>Trade: | IMMULITE 2000 Thyroglobulin | | |
| Catalog Number: | L2KTY2 (200 tests) | | |
| Common: | Reagent system for the determination of thyroglobulin in<br>serum or heparinized plasma. | | |
| Classification: | Class II device, 82-JZO (21CFR 866.5870) | | |
| Manufacturer: | EURO/DPC Ltd. (Manufacturing under a Quality System -<br>ISO9001/EN29001/BS 5750 | | |
| Sole U.S. Importer: | Diagnostic Products Corporation<br>5700 West 96th Street<br>Los Angeles, California 90045-5597 | | |
| Establishment Registration<br>Number | EURO/DPC: Not applicable<br>DPC:<br>2017183 | | |
| Substantially Equivalent<br>Predicate Device: | ORGenTec Thyroglobulin ELISA (K972190)<br>Manufactured by ORGenTec, and distributed in the USA<br>by ALPCO, Windham, NH | | |
| Description of Device: | IMMULITE 2000 Thyroglobulin is a clinical device for use<br>with the IMMULITE 2000 Automated Immunoassay<br>Analyzer. | | |
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#### Intended Use of the Device:
IMMULITE 2000 Thyroglobulin is a two-site chemiluminescent immunometric assay for use with the IMMULITE 2000 Analyzer and designed for the quantitative measurement of thyroglobulin in serum or heparinized plasma. It is intended strictly for in vitro diagnostic use as an aid in monitoring patients who have undergone thyroidectomy.
#### Performance Equivalence:
Diagnostic Products Corporation (DPC) asserts that the IMMULITE 2000 Thyroglobulin produces substantially equivalent results to other commercially marketed thyroglobulin assays, such as the ORGenTec Thyroglobulin ELISA. Each product is intended strictly for in vitro diagnostic use for the management of thyroid disease.
#### Summary and Explanation of the Test:
Thyroglobulin (TG) is a heterogeneous iodoglycoprotein which has a molecular mass of approximately 660.000 daltons. Thyroglobulin is normally synthesized in the follicular cells of the thyroid gland, under the influence of thyrotropin, and represents the precursor to thyroxine and the other iodothyronines.
The expected upper limit of normal for circulating thyroglobulin is approximately 40 to 60 ng/mL, with a median of 5 to 10 ng/mL. Somewhat higher values are encountered in newborns and during the third trimester of pregnancy. Thyroglobulin levels also tend to be elevated in regions of endemic goiter.
The major clinical applications for measurement of this prohormone derive from the fact that functioning thyroid tissue appears to be the only source of circulating thyroglobulin. Accordingly, thyroglobulin determinations have been widely used to complement radioiodine scanning and other techniques (such as ultrasound or immunohistochemical staining) as an aid in identifying the presence or absence of functioning thyroid tissue, or an increase in such tissue relative to an individually established baseline. The differential diagnosis of congenital hypothyroidism is a well-established context of use for this application of serum thyroglobulin measurements.
#### Congenital Hypothyroidism
Thyroglobulin determinations have been used, sometimes in conjunction with ultrasound and radioiodine scanning, to help clarify the type of thyroid defect in previously diagnosed congenital hypothyroidism. Very low or undetectable thyroglobulin levels are expected in infants born without thyroid tissue (thyroid agenesis), whereas higher, but widely varving levels are generally encountered in infants with hypoplastic thyroid glands, ectopic thyroid tissue. dyshormonogenic goiter, congenital TBG deficiency or transient hypothyroidism.
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## Summary and Explanation of the Test (continued):
#### Other Applications
Thyroglobulin measurements may also be of value in helping to distinguish subacute thyroiditis from thyrotoxicosis caused by covert administration of thyroid hormones. In the latter event, low levels of thyroglobulin are expected due to thyroid hormone suppression of thyrotropin.
## Technological Comparison to Predicate:
IMMULITE 2000 Thyroglobulin is a chemiluminescent enzyme-labeled immunometric assay, based on ligand-labeled monoclonal antibody and separation by anti-ligand-coated solid phase.
The patient sample, a ligand-labeled anti-thyroglobulin monoclonal antibody and an alkaline phosphatase-labeled anti-thyroglobulin polyclonal antibody are simultaneously introduced into the Reaction Tube containing the bead and incubated for approximately 60 minutes at 37℃ with intermittent agitation. During this time, thyroglobulin in the sample forms an antibody sandwich complex which, in turn, binds to anti-ligand on the solid phase. Unbound conjugate is removed by a centrifugal wash; substrate is then added and the Reaction Tube is incubated for a further 5 minutes.
The chemiluminescent substrate, a phosphate ester of adamantyl dioxetane, undergoes hydrolysis in the presence of alkaline phosphatase to yield an unstable intermediate. The continuous production of this intermediate results in the sustained emission of light, thus improving precision by providing a window for multiple readings. The bound complex - and thus also the photon output, as measured by the luminometer - is proportional to the concentration of thyroglobulin in the sample.
The ORGenTec Thyroglobulin assay is an indirect solid phase enzyme immunometric assay based on precoated microplates in strip format (12x8 wells), ideal for smaller runs, or economical batch processing. The Thyroglobulin assay takes place in three separate phases:
#### Phase 1:
Microplate wells are coated with highly specific anti-TG antibodies. Standards, controls and undiluted patient samples are pipetted into the wells of the first microplate. Sample buffer is added to appropriate wells. Recovery control is added to patient sample for recovery test. Any thyroglobulin molecules present bind to the inner well surfaces. After a 60 minute incubation, the microplate is washed with wash buffer to remove non-reactive serum components.
#### Phase 2:
An anti-thyroglobulin peroxidase conjugate solution is pipetted into the microplate wells which recognizes the thyroglobulin bound to the immobilized antibody. After a 60 minute incubation, excess conjugate is washed away.
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### Technological Comparison to Predicate (continued):
#### Phase 3:
A chromogenic substrate solution containing TMB (3,3' 5,5'-tetramethyl-benzidine) is pipetted into the microplate wells. During a 15 minute incubation changes to a blue color. 1 M hydrochloric acid is added to stop color development.
The amount of color is directly proportional to the concentration of TG present in the original The optical density for each standard may be graphically plotted against the sample. concentration of TG and unknowns extrapolated from the curve. Optical density is read at 450 nm. Bichromatic measurement with a 650 nm reference is recommended.
## Method Comparison:
The IMMULITE 2000 Thyroglobulin procedure was compared to Kit A (ALPCO's ORGenTec), a commercially available indirect solid phase enzyme immunometric assay for thyroglobulin, on 150 samples from patients with Hashimoto's disease, Graves disease, patients who had undergone thyroidectorny, as well as euthyroid individuals. The thyroglobulin concentrations of these specimens covered the entire calibration range of the assay. The data were tabulated in reference to the respective assays' suggested cutoffs, with the following results:
| | IMMULITE 2000 | | | N | 150 |
|-------|---------------|-----|------|-------------|--------|
| Kit A | >50 | 10 | 0 | Agreement | 93.3% |
| | <=50 | 10 | 130 | Sensitivity | 100.0% |
| | | >55 | <=55 | Specificity | 92.9% |
95% Confidence Limits for Relative Sensitivity and Specificity. respectively: 69.2% - 100%, 87.3% - 96.5%.
The same data, excluding one specimen in the above analysis due to its thyroglobulin level exceeding both assays' upper calibration limits, yielded the following result in a linear regression analysis:
IMMULITE 2000 = 2.29 × Kit A + 0.05 ng/mL r = 0.95
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Conclusion:
The data presented in this summary of safety and effectiveness is the data that the Food and Drug Administration used in granting DPC substantial equivalence for IMMULITE 2000 Thyroglobulin.
Edward Klein
Edward M. Levine, Ph.D. Director of Clinical Affairs
2/12/87
**Date**
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Image /page/5/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. Inside the circle is an abstract symbol that resembles a stylized caduceus or a representation of the human form.
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
MAR 1 2 1999
Edward M. Levine, Ph.D. Director of Clinical Affairs Diagnostic Products Corporation 5700 West 96th Street Los Angeles, CA 90045-5597
Re: K982468 Trade Name: IMMULITE® 2000 Thyroglobulin Regulatory Class: II Product Code: MSW Dated: February 12, 1999 Received: February 16, 1999
Dear Dr. Levine:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic OS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
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#### Page 2
Under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88), this device may require a CLIA complexity categorization. To determine if it does, you should contact the Centers for Disease Control and Prevention (CDC) at (770)488-7655.
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll free number (800) 638-2041 or at (301) 443-6597 or at its internet address "http://www.fda.gov/cdrh/dsmamain.html"
Sincerely yours,
Steven Autman
Steven I. Gutman, M.D., M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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510(k) Number (if known): Device Name: IMMULITE® 2000 Thyroglobulin
Indications For Use:
IMMULITE 2000 Thyroglobulin is a two-site chemiluminescent immunometric assay for use with IMMOLITE 2000 Thyrogioum. Is a wontitative measurement of thyroglobulin in mo more of a see of as a lasma. It is intended strictly for in vitro diagnostic use as an aid in monitoring patients who have undergone thyroidectomy
Rita E. Mapin
(Division Sign-Division of Clinical Laboratory I 510(k) Numb
# (PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)
# Concurrence of CDRH, Office of Device Evaluation (ODE)
Prescription Use
(Per 21 CFR 801.109)
OR
Over-The-Counter Use
(Optional Format 1-2-96)
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Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.