K991717 · Careside, Inc. · JGJ · Aug 10, 1999 · Clinical Chemistry
Device Facts
Record ID
K991717
Device Name
CARESIDE MG
Applicant
Careside, Inc.
Product Code
JGJ · Clinical Chemistry
Decision Date
Aug 10, 1999
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 862.1495
Device Class
Class 1
Indications for Use
The CARESIDE™ Mg cartridge is intended for in vitro diagnostic use in conjunction with the CARESIDE Analyzer™ to quantitatively measure magnesium concentration in anti-coagulated whole blood, plasma or serum.
Device Story
CARESIDE™ Mg is a single-use disposable cartridge for quantitative magnesium measurement in anti-coagulated whole blood, plasma, or serum. Used with the CARESIDE Analyzer™ in professional laboratory settings. User loads specimen into cartridge well; analyzer scans barcode, heats to 37°C, and spins to distribute sample onto a multi-layer reagent film. Magnesium reacts with ATP and glycerol via glycerol kinase (GK) and glycerol phosphate oxidase (GPO) to produce hydrogen peroxide, which reacts with a leuco dye via peroxidase (POD) to form a green dye. Analyzer measures reflectance at 655 nm over time. Reflectance data and lot-specific standard curves calculate magnesium concentration. Output aids clinicians in diagnosing/treating magnesium-related disorders (e.g., hypomagnesemia, hypermagnesemia).
Clinical Evidence
Bench testing only. Performance evaluated via method comparison against Hitachi 902/BMD (r=0.99) and Vitros DT 60 II (r=0.99). Detection limit 0.2 mg/dL; reportable range 0.2–7.0 mg/dL. Precision (Total CV) 4.3% at 1.2 mg/dL. Interference testing showed no significant interference from ascorbic acid, bilirubin, calcium, phosphorus, total protein, or triglycerides at tested concentrations.
Technological Characteristics
Single-use cartridge with multi-layer reagent film. Reagents: glycerol, glycerol kinase, glycerol kinase oxidase, leuco dye. Sensing: reflectance photodiode at 655 nm. Energy: analyzer-powered heating (37°C) and centrifugation. Connectivity: barcode-based lot-specific calibration. Software: automated processing of reflectance time-course data.
Indications for Use
Indicated for professional laboratory use to quantitatively measure magnesium in anti-coagulated whole blood, plasma, or serum to aid in the diagnosis and treatment of patients with hypomagnesemia or hypermagnesemia. Not for point-of-care or physician office laboratory use.
Regulatory Classification
Identification
A magnesium test system is a device intended to measure magnesium levels in serum and plasma. Magnesium measurements are used in the diagnosis and treatment of hypomagnesemia (abnormally low plasma levels of magnesium) and hypermagnesemia (abnormally high plasma levels of magnesium).
Predicate Devices
Johnson and Johnson's (formerly Eastman Kodak, Inc.) Vitros Mg DT Slides for use on the Vitros DT 60 II system (K912844/A)
Reference Devices
Hitachi 902/BMD
Submission Summary (Full Text)
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CARESIDE, Inc. Page 10
AUG 11 1999
# 510(K) SUMMARY: CARESIDE™ MG SAFETY A IV. EFFECTIVENESS
### I. Applicant Information
- Applicant Name A.
- Applicant/Manufacturer Address B.
- Telephone Number C.
- Contact Person D.
- E. FAX Number
- F. e-Mail Address
- Date 510(k) Summary prepared G.
### II. Device Information
- A. Device Name (Trade)
- Device Name (Classification) B.
- C. Device Classification
# CARESIDE, Inc.
6100 Bristol Parkway Culver City, CA 90230 310-338-6767 Kenneth B. Asarch, Pharm.D., Ph.D. 310-338-6789 AsarchK@CARESIDE.com May 19, 1999
# CARESIDE™ Mg
Magnesium test system Clinical chemistry panel Mg test system Regulation Number: 21 CFR 862.1495 Regulatory Class I Classification Number: 75JGJ None applicable
- D. Special controls and performance standards
#### III. Substantial Equivalence Claim
- General equivalency claim A.
The ability to monitor analyte-specific biochemical reactions in dry film and other formats is widely recognized and has gained widespread acceptance for use in clinical chemistry assays.
Magnesium in vitro diagnostic products, in both dry film and other formats, are already on the U.S. market. In vitro diagnostic products in dry film format also employ enzymatic coupling to indirectly measure the analyte of interest.
#### B. Specific equivalency claim
This CARESIDE™ Mg test is substantially equivalent in principle, intended use, and clinical performance to the currently marketed Vitros slides for the quantitative measurement of magnesium for use on the Vitros DT 60 II system.
| Name of Predicate Device: | Johnson and Johnson's (formerly Eastman Kodak,<br>Inc.) Vitros Mg DT Slides for use on the Vitros DT<br>60 II system (formerly Eastman Kodak's DT 60 II). |
|-------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------|
| Predicate Device 510K number: | K912844/A |
| Product Code: | 75JGJ |
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#### IV. Device Description
CARESIDE™ Mg cartridges are used with the CARESIDE, Inc. CARESIDE Analyzer™ to measure magnesium in anti-coagulated whole blood, plasma or serum specimens. The CARESIDE™ Mg cartridge, a single use disposable in vitro diagnostic test cartridge, delivers a measured volume of plasma or serum to a dry film to initiate the measurement of magnesium concentration. The film cartridge (patent pending) contains all reagents necessary to measure magnesium concentration.
#### A. Explanation of Device Function
Each CARESIDE™ Mg cartridge consists of a magnesium-specific multi-layer reagent film mounted in a plastic base with a hinged lid. The user introduces the specimen into the cartridge Sample Well, closes the lid and inserts the cartridge into the CARESIDE Analyzer™.
Once loaded, the CARESIDE Analyzer™ scans the cartridge barcode, brings the cartridge and the contained speciment to 37°C, and spins the cartridge to move the sample from the Sample Well into the cartridge channels and chambers. 8.5 µL microliters of sample remains in the metering passage. Any excess sample flows into the Overflow Well.
The sample is automatically dispensed onto the multi-layer film. The spreading layer distributes the sample evenly on the film before it moves onto a reaction layer where magnesium in the sample complexes with ATP to serve as a substrate in the glycerol kinase (GK) catalyzed reaction with glycerol to form L-a-glycerol-3-phosphate. Hydrogen peroxide (H202) and dihydroxyacetone phosphate (DAP) is formed in a glycerol phosphate oxidase (GPO) catalyzed reaction of L-α-glycerol-3-phosphate (L-a-GP) with oxygen. The H202 produced reacts with a leuco dye in a peroxidase (POD) catalyzed reaction to form a green dye. The rate of change of the color intensity of the dye, as measured by the time course of reflected light at 655 nanometers, and directly relates to the magnesium concentration of the specimen.
# Test Reaction Sequence:
Mg-ATP + Glycerol ------------------------------------------------------------------------------------------------------------------------------------------------------------GPO → H2O2 + DAP L-a-GP + 02 -H2O2 + Leuco Dye - POD -> Green Dye + 2 H2O
As the cartridges spin, a photodiode measures reflectance of light emitted by a wavelength-specific light emitting diode (LED) over a fixed time period. The analyzer uses the reflectance measurements and the lot-specific standard curve to calculate the magnesium concentration.
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#### B. Test Summary
Magnesium has essential functions intracellularly, extracellularly, and in the skeleton in the human body. Intracellularly, magnesium is a cofactor for more than 300 enzymes. Magnesium is needed for the physiological processes of oxidative phosphorylation, glycolysis, cell replication, nucleotide metabolism, and protein biosynthesis. Extracellularly, magnesium is involved in the regulation of nerve conduction and neuromuscular transmission. Magnesium is incorporated into the mineral lattice of the About one-third of the skeletal magnesium is exchangeable with the skeleton. extracellular fluid which in turn serves as a source for maintaining intracellular magnesium.
Magnesium deficiency is a very common sign in a variety of diseases. Causes of hypomagnesemia include gastrointestinal disorders, renal disease, alcohol and other drugs, metabolic acidosis, diabetes mellitus, increased sodium or calcium excretion, and phosphate depletion. Hypomagnesemia most commonly presents with neuromuscular hyperexcitability, although the features of the primary disease process causing the magnesium deficiency may mask the signs and symptoms.
Hypermagnesemia is encountered less commonly than hypomagnesemia. Causes of hypermagnesemia include excessive magnesium intake, renal failure, familial hypocalciuric hypercalcemia, and lithium ingestion. Hypermagnesemia most commonly presents with neuromuscular symptoms, such as the disappearance of the deep tendon reflex.
#### V. Intended Use
#### Intended Use A.
The CARESIDE™ Mg cartridge is intended for in vitro diagnostic use in conjunction with the CARESIDE Analyzer™ to quantitatively measure magnesium concentration in anti-coagulated whole blood, plasma or serum.
#### B. Indications for Use
For in vitro diagnostic use with the CARESIDE Analyzer™ to quantitatively measure magnesium from anti-coagulated whole blood, plasma, or serum specimens to aid in the diagnosis and treatment of patients with hypomagnesemia or hypermagnesmia. It is intended professional laboratory use: not for point of care or physician office laboratory use.
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## VI. Technological Characteristics
### Similarities A.
| | CARESIDE™ Mg | Vitros Mg DT Slides |
|-------------------|-------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------|
| Intended Use | Primarily to aid in the diagnosis<br>and treatment of patients with<br>with hypomagnesemia or<br>hypermagnesmia. | Same. |
| Indications | For <i>in vitro</i> diagnostic use.<br>For professional laboratory:<br>not for point of care or<br>physician office laboratory use. | For <i>in vitro</i> diagnostic use |
| Measurement | Quantitative | Same |
| Method Principle | Reflectometry of enzymatically<br>coupled production of dye from<br>magnesium reaction product. | Complexation of magnesium<br>with formazan dye to form a<br>colored complex. |
| Specimen dilution | Not required | Same |
| Materials | Glycerol, glycerol kinase,<br>glycerol kinase oxidase, and<br>leuco dye. | Formazan dye |
| Detector | Reflectance (655 nm) | Reflectance (660 nm) |
| Test time | 4 minute warm-up (on-board)<br>plus 4.5 minute test time. | 15 minutes slide warm-up<br>(off-line) plus 5 minutes test<br>time. |
| Sample Type | Anti-coagulated whole blood,<br>plasma, or serum | Plasma or serum |
| Specimen volume | 8.5 µl test volume<br>(85 ± 15 µl applied volume) | 10 µl |
| Calibration | Calibration information<br>bar-coded on each cartridge.<br>Calibration information may<br>change with each lot. | Run Vitros DT II calibrators<br>whenever a new slide lot is<br>used or when necessary. |
| Quality Control | 2 levels | Same |
| Reporting Units | mg/dL | Same |
| Reaction Temp. | 37°C | Same |
## B. Differences
| | CARESIDE™ Mg | Vitros Mg DT Slides |
|------------------------|--------------|---------------------|
| Accurate<br>pipetting | Not required | Required |
| Reagent<br>pre-warming | Not required | Required |
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、
## C. Comparative Performance Characteristics
| | CARESIDE™ Mg | Vitros Mg DT Slides |
|----------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------|
| Detection limit | 0.2 mg/dL | 0.2 mg/dL |
| Reportable range | 0.2 to 7.0 mg/dL | 0.2 to 7.0 mg/dL |
| Accuracy | Mean recovery 97% | Not provided |
| Precision | Total CV, 1.2 mg/dL, 4.3% | Total CV, 1.1 mg/dL, 3.6% |
| Method<br>comparison | CARESIDE™ Mg = 0.98 (Hitachi 902/BMD) – 0.086 mg/dL, r = 0.99<br>CARESIDE™ Mg = 0.82 (Vitros DT 60 II) + 0.31 mg/dL, r = 0.99 | |
| Linearity | Linearity yielded slope and<br>correlation coefficient within<br>acceptable limits. | Not provided |
| Interference | No significant interference<br>observed at tested<br>concentration of interferent:<br>Ascorbic Acid, 10 mg/dL<br>Bilirubin, 60 mg/dL<br>Calcium, 20 mg/dL<br>Inorg. Phosphorus, 9 mg/dL<br>Total Protein, 9 g/dL<br>Triglycerides, 2000 mg/dL | Calcium 20 mg/dL<br>Inorg. Phosphorus 9 mg/dL |
### D. Conclusion
The nonclinical and clinical data provided demonstrate that the CARESIDE™ Mg product is as safe, effective, and performs as well as or better than the legally marketed predicate device.
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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 stylized eagle with three stripes forming its body and wing. The eagle is facing right. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is arranged in a circular fashion around the eagle.
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
AUG 10 1999
Mr. Kenneth B. Asarch, Ph.D. VP Quality Systems and Regulatory Affairs Careside, Inc. 6100 Bristol Parkway Culver City, California 90230
Re: K991717
> Trade Name: CARESIDE™ Magnesium (Mg) Regulatory Class: II Product Code: JGJ Dated: May 19, 1999 Received: May 20, 1999
Dear Dr. Asarch:
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 QS 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 (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsma/dsmamain.html".
Sincerely yours,
Steven Putman
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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# INDICATIONS FOR USE VI.
510(k) Number:
K 9917i7
Device Name:
CARESIDE™ Mg
For in vitro diagnostic use with the CARESIDE Analyzer™ to · Indications for use: montitatively measure magnesium from anti-coagulated whole blood, plasma, or serum speciments to aid in the diagnosis and treatment of patients with hypomagnesemia or specifical to the in the intended professional laboratory use: not for point of care or physician office laboratory use.
Sean Cooper
(Division Sign-Off)
Division of Clinical Laboratory Devices 510(k) Number
# (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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