K980057 · Exigent Diagnostics, Inc. · CDQ · Feb 5, 1998 · Clinical Chemistry
Device Facts
Record ID
K980057
Device Name
CARESIDE BUN
Applicant
Exigent Diagnostics, Inc.
Product Code
CDQ · Clinical Chemistry
Decision Date
Feb 5, 1998
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 862.1770
Device Class
Class 2
Indications for Use
The CareSide™ BUN cartridge is intended for in vitro diagnostic use in conjunction will the Exigent Diagnostics CareSidc™ Analyzer to quantitatively measure urea nitrogen from whole blood, plasma or serum by laboratory professionals. When used in conjunction with the Exigent Diagnostics CareSideTM Creatinine test cartridge on the Exigent Diagnostics CareSide™ Analyzer, the BUN product may be used to calculate a BUN to creatinine ratio. The CareSide™ BUN test aids in the diagnosis and treatment of various renal and metabolic diseases.
Device Story
CareSide™ BUN cartridge is a single-use disposable test used with the Exigent Diagnostics CareSide™ Analyzer. Input: whole blood, plasma, or serum specimen. Operation: user deposits sample into cartridge; analyzer heats to 37°C and spins to separate blood cells from plasma/serum. Plasma is metered onto a multi-layer reagent film where urea reacts with urease to produce ammonia gas. Ammonia reacts with bromocresol green dye to form a green color. Photodiodes measure reflectance at 615 nm. Analyzer uses lot-specific standard curve to calculate BUN concentration. Output: quantitative BUN concentration (mg/dL or mmol/L). Used by laboratory professionals in clinical settings. Aids in diagnosis/treatment of renal and metabolic diseases by evaluating kidney and liver function.
Clinical Evidence
Bench testing only. Method comparison against Vitros BUN DT showed correlation (r=0.99, y=1.00x-3.0). Precision reported as total CV of 3.3% at 26 mg/dL. Linearity mean deviation approx -6% (r>0.99). No significant interference observed for ascorbic acid (10 mg/dL), bilirubin (20 mg/dL), hemoglobin (500 mg/dL), or triglycerides (3000 mg/dL).
Technological Characteristics
Dry film reagent cartridge; urease (Canavalia ensiformis) and bromocresol green indicator. Reflectance photometry at 615 nm. On-board heating to 37°C. Centrifugal sample separation. Barcode-based calibration. Quantitative measurement range 5-140 mg/dL. Sample volume 10 μl.
Indications for Use
Indicated for use with patients with various renal and metabolic diseases. For professional in vitro diagnostic use.
Regulatory Classification
Identification
A urea nitrogen test system is a device intended to measure urea nitrogen (an end-product of nitrogen metabolism) in whole blood, serum, plasma, and urine. Measurements obtained by this device are used in the diagnosis and treatment of certain renal and metabolic diseases.
Predicate Devices
Johnson and Johnson's Vitros BUN Slides (K912844/A)
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PHONE NO. : 3103386789
98005
FEB - 5 1998
Exigent Diagnostics, Inc. Page 13
CarcSide™ Urea Nitrogen (BUN) Premarket Notification K980057 revised on January 28, 1998
### CareSide™ Urea Nitrogen (BUN) V. 510(k) Summary: Safety and Effectiveness
#### Applicant Information I.
#### Applicant Name A.
- Applicant/Manufacturer Address B.
- Telephone Number C.
- D. Contact Person
- FAX Number E.
- e-Mail Address F.
- Date 510(k) Summary prepared G.
#### Device Information II.
- Device Name (Trade) A.
- Device Name (Classification) B.
- Device Classification C.
## Exigent Diagnostics, Inc. 6100 Bristol Parkway Culver City, CA 90230 310-338-6767 Kenneth B. Asarch, Pharm.D., Ph.D. 310-338-6789 asarchk@worldnet.att.net January 28, 1998
- CareSide™ Urea Nitrogen (BUN) BUN icst system Clinical chemistry panel BUN test system Regulation Number: 21 CFR 862.1770 Regulatory Class II Product Code: 75CDN Tier I None applicable
- D. Device Tier
- E. Special controls and performance standards
#### Substantial Equivalence Claim III.
#### General equivalency claim A..
The ability to monitor analyte-specific blochemical reactions in dry film and other formats is widely recognized and has gained widespread acceptance for use in chemistry assays.
BUN in vitro diagnostic products, in both dry film and other formats, are already on the U.S. market, including BUN products which utilize urease with an ammonia indicator dye.
#### B. Specific couivalency claim
This CareSide BUN test is substantially equivalent in principle, intended use, and clinical performance to the currently marketed Vitros slides for the quantitative measurement of BUN on the Vitros DT 60 II.
Name of Predicate Device:
Johnson and Johnson's Vitros BUN Slides (formerly Pastman Kodak, Inc.) and Johnson and Johnson's Vitros DT 60 (formerly Eastman Kodak's DT 60 II),
K912844/A Predicate Device 510K number: 75CDN (urease, urea) Product Codc:
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Exigent Diagnostics, Inc. Page 13a
#### IV. Device Description
CareSide™ BUN cartridges are used with the Exigent Diagnostics CareSide™ Analyzer to measure BUN concentration in whole blood, plasma or scrum specimens. The CareSide™ BUN cartidge, a single use disposable in viro diagnostic test cartridge, aids in specimen separation and delivers a measured volume of plasma or serum to a dry film to initiate the measurement of BUN concentration. The film cartridge (patcht pending) contains all reagents necessary to measure Concentration. "The min and in conjunction with the CareSide™ Creatinine cartridge on the CareSide™ Analyzer, the analyzer calculates a BUN to creatinine ratio.
#### Explanation of Device Function A.
Each Exigent Diagnostics CareSide™ BUN cartridge consists of a BUN-specific multi-Jayer reagent film mounted in a plastic base with a hinged lid. The user introduces the whole blood, serum, or plasma specimen into the cartridge sample deposition well, closes the lid and inserts the cartridge into the Exigent Diagnostics CareSide™ Analyzer.
Once loaded, the CareSide™ analyzer scans the carridge barcode, brings the cartidge and the contained speciment to 37℃, and spins the cartidge to move the sample from the sample deposition well into the cartridge channels and chambers. As the cartridge continues to spin, the blood culls are separated from the plasmalscrum and the cells accumulate in the separation well. Ten microliters of plasma (or serum, as applicable) remain in the metering passage. Any excess sample flows into an overflow well,
The ten microliters of plasma (or serum, as applicable) is automatically dispensed onto the multi-layer reagent film. The spreading layer distributes the sample evenly on the film and filters large molecular weight components such as protein and dye fragments hefore the specimen enters the reaction layer. Urea then reacts with water in a urcasccatalyzed reaction to produce carbon dioxide and ammonia gas in the alkaline unvironment. The arnmonia gas permeates the porous gas permeation layer to reach the detection layer where it then reacts non-cazymatically with the yellow dye, hromocresol green, to form a green dye.
Test Reaction Sequence:
Urea + H2O - "Pease > 2NH3 + CO2
Bromocresol green (yellow) + NH3-> Green dye
As the cartridges spin, photodiodes measure reflectance of light emitted by wavelengthspecific light cmitting diodes (LEDs) at a lixed time. The analyzer uses the reflectance measurements and the lot-specific standard curve to calculate BUN concontration.
#### B. Test Summary
Urea is the principal waste product of protein catabolism. Urea is synthesized in the liver from ammonia which is produced as a result of deamination of amino acids. Normally, urca nitrogen in the blood comprises only ahout 45% of protein nitrogen. Urea nitrogen determinations are important in evaluating the function of the kidneys and the liver. Increases in urea nitrogen lovels may be due to prerenal causes (cardiac decompensation, water depletion due to increased intake or excessive loss, or increased catabolism), or renal causes (acute glomerulonephritis, chronic nophritis, polycystic kidney). Increases in urea nitrogen are also seen in metallic poisonia, Addison's disease, perionitis, and surgical shock. Decreases in blood urea nitrogen are seen with nephrosis, acure liver destruction, amyloidosis and pregnancy.
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Exigent Diagnostics, Inc. Page 13b
#### Intended Use V.
#### Intended Use A.
The CareSide™ BUN cartridge is intended for in vitro diagnostic use in conjunction will the Exigent Diagnostics CareSidc™ Analyzer to quantitatively measure urea nitrogen from whole blood, plasma or serum by laboratory professionals. When used in conjunction with the Exigent Diagnostics CareSideTM Creatinine test cartridge on the Exigent Diagnostics CareSide™ Analyzer, the BUN product may be used to calculate a BUN to creatinine ratio. The CareSide™ BUN test aids in the diagnosis and treatment of various renal and metabolic diseases.
#### Indications for Use B.
This product is indicated for use with patients with various renal and metabolic diseases.
#### VI. Technological Characteristics
- Similaritics A.
| | CareSide™ BUN | Vitros BUN DT Slides |
|-------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------|
| Intended Use | Primarily to aid in the diagnosis and treatment of certain renal and metabolic diseases. | Same |
| Indications | For <i>in vitro</i> diagnostic use.<br>For professional use only. | For <i>in vitro</i> diagnostic use. |
| Measurement | Quantitative | Same |
| Reportable range | 5 to 140mg/dL | 1 to 100mg/dL |
| Method Principle | Dry film based urease conversion to ammonia and reaction with ammonia indicating dye. Chromogen quantitated by reflectance measurement after fixed time. | Same |
| Specimen dilution | Not required | Same |
| Materials Source | Urease: ( <i>Canavalia ensiformis</i> )<br>Indicator: Bromocresol green (synthetic) | Urease: (Jack bean)<br>Indicator: N-propyl-4-(2,6-dinitro-4-chlorobenzyl)-quinolinionethane sulfonate (synthetic) |
| Detector | Reflectance (615 nm) | Reflectance (660 nm) |
| Test time | Approximately 4 minute warm-up (on-board) plus 6 minute test time. | 15 minutes slide warm-up (off-line) plus 5 minutes test time. |
| Reference Method | Urease conversion to ammonia.<br>Glutamic dehydrogenase linked NADH oxidation of ammonia. | Same |
| Sample Type | Serum, plasma, whole blood (wb) [wb applied sample, plasma test sample] | serum, plasma |
| Specimen volume | 10 μl test volume<br>(85 ± 15 μl applied volume) | 10 μl |
| Calibration | Calibration information bar-coded on each cartridge. Calibration information may change with each lot. | Run Vitros DT II calibrators whenever a new slide lot is used or when necessary. |
| Quality Control | 2 levels | Same |
| Reporting Units | mg/dL or mmol/L | Same |
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Exigent Diagnostics, Inc. Page 13c
CareSide™ Urea Nitrogen (BUN) Premarket Notification K980057 revised on January 28, 1998
- B. Differences
| | CareSide™ BUN | Vitros BUN DT Slides |
|--------------------------|------------------|--------------------------------------------------------------------------|
| Direct blood<br>specimen | Yes, whole blood | No, requires separation of<br>whole blood prior to sample<br>application |
| Accurate<br>pipetting | Not required | Required |
| Reagent pre-<br>warming | Not required | Required |
Comparative Performance Characteristics C.
| | CareSide™ BUN | Vitros BUN DT Slides |
|------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------|
| Detection limit | 5 mg/dL | 1 mg/dL |
| Reportable range | 5 to 140 mg/dL | 1 to 100 mg/dL |
| Accuracy | Mean recovery 100% | Not provided |
| Precision | Total CV, 26 mg/dL, 3.3% | Total CV, 27 mg/dL, 3.3% |
| Method<br>comparison | CareSide™ = 1.00 (Vitros BUN DT) - 3.0, r=0.99 | |
| Linearity | Mean deviation approx -6%,<br>r>0.99 | Not provided |
| Interference | No significant interference observed at tested concentration of interferent:<br>Ascorbic Acid, 10 mg/dL<br>Bilirubin, 20 mg/dL<br>Hemoglobin, 500 mg/dL<br>Triglycerides 3000 mg/dL | Not provided |
| Specimen Types<br>& Anticoagulants | No clinically significant difference between<br>heparinized whole blood, serum, heparin plasma, and EDTA plasma. | No clinically significant difference between serum and heparin plasma. Whole blood is unsuitable. |
| Expected Values | 6 to 16 mg/dL<br>(combined male and female)<br>Central 95% interval | 9 to 20 mg/dL (male)<br>7 to 17 mg/dL (female)<br>Central 95% interval |
#### D. Conclusion
The nonclinical and clinical data provided demonstrate that the CareSide™ BUN product is as safe, effective, and performs as well as or better than the legally marketed predicate device.
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Kenneth B. Asarch, Ph.D.
Exigent Diagnostics Inc. 6100 Bristol Parkway
Image /page/4/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo is a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES • USA" arranged around the top half of the circle. Inside the circle is a stylized image of an eagle with its wings outstretched.
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
FEB - 5 1998 VP Quality Systems and Regulatory Affairs
Culver City, California 90230 K980057 Re : CareSide™ BUN Requlatory Class: II
Product Code: CDQ Dated: December 30, 1997 Received: January 6, 1998
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 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 The general controls provisions of provisions of the Act. 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 Good Manufacturing Practice for Medical Devices: General (GMP) regulation (21 CFR Part 820) and-that, through periodic GMP 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 Reqister. 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/dsmamain.html".
Sincerely yours,
Steven Gutman
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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Page / of /
510(k) Number (if known): K980057
Device Name:_
# VII. Indications for Use
510(k) Number: Device Name: Indications for use:
To be assigned CareSide™ BUN For in vitro diagnostic use with Exigent Diagnostics CareSide™ Analyzer to measure BUN in whole blood, plasma or serum specimens by professionals to aid in the diagnosis and treatment of various renal and metabolic diseases.
(Please do not write below this lìne-continue on another page if NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Prescription Use_ V (Per 21 CFR 801.109)
| OR | Over-The-Counter Use |
|----|----------------------|
|----|----------------------|
| (Optional Format 1-2-96) |
|--------------------------|
|--------------------------|
| (Division Sign-Off) |
|-----------------------------------------|
| Division of Clinical Laboratory Devices |
| 510(k) Number | 980057 |
|---------------|--------|
|---------------|--------|
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