(29 days)
Not Found
No
The device description and performance studies focus on chemical reactions and standard analytical methods, with no mention of AI or ML.
No.
This device is for in vitro diagnostic use, meaning it measures substances in samples taken from the body (like blood or urine) to aid in diagnosis. It does not directly provide therapy or treatment to a patient.
Yes
The "Intended Use / Indications for Use" section explicitly states that the measurements obtained by this device are "used in the diagnosis and treatment of certain renal and metabolic diseases" and that it is "For in vitro diagnostic use only". These statements clearly indicate its purpose as a diagnostic device.
No
The device description clearly details a physical, multilayered analytical element coated on a polyester support, which is a hardware component used for in vitro diagnostic testing.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Explicit Statement: The "Intended Use / Indications for Use" section clearly states: "For in vitro diagnostic use only".
- Purpose: The device is designed to quantitatively measure specific analytes (urea and creatinine) in biological samples (serum, plasma, and urine) outside of the body.
- Clinical Use: The measurements obtained are used in the "diagnosis and treatment of certain renal and metabolic diseases" and for "renal dialysis, and as a calculation basis for measuring other urine analytes." This directly aligns with the purpose of IVD devices, which are used to provide information for diagnostic purposes.
- Device Description: The description details the chemical reactions that occur on the slide when a patient sample is applied, which is characteristic of an in vitro test.
- Performance Studies: The performance studies described (Method Comparison, Precision, Detection Capability, Linearity, Specificity) are standard evaluations performed for IVD devices to demonstrate their analytical performance.
- Predicate Devices: The predicate devices listed are also IVD products (VITROS Chemistry Products BUN/UREA Slides and VITROS Chemistry Products CREA Slides).
All of these factors strongly indicate that this device is intended for and functions as an In Vitro Diagnostic product.
N/A
Intended Use / Indications for Use
For in vitro diagnostic use only
The UREA test within the VITROS XT Chemistry Products UREA-CREA Slides quantitatively measures urea concentration, reported either as urea nitrogen or as urea (UREA), in serum, plasma, and urine using the VITROS XT 7600 Integrated System. Measurements obtained by this device are used in the diagnosis and treatment of certain renal and metabolic diseases
The CREA test within the VITROS XT Chemistry Products UREA-CREA Slides quantitatively measures creatinine (CREA) concentration in serum, plasma, and urine using the VITROS XT 7600 Integrated System. Creatinine measurements are used in the diagnosis and treatment of renal diseases, in monitoring renal dialysis, and as a calculation basis for measuring other urine analytes.
Special conditions for use statement: For prescription use only.
Product codes
CDN, JFY
Device Description
The new device, the VITROS XT Chemistry Products UREA-CREA Slide is a single device that contains both a UREA test and a CREA test multilayered, analytical element coated on a polyester support separated by a plastic barrier sealed within a single slide frame. In this format, individual reactions occur and test results are generated for each analyte independently of the other analyte.
To perform the UREA test, a drop of patient sample is deposited on the slide and is evenly distributed by the spreading layer to the underlying layers. Water and nonproteinaceous components then travel to the underlying reagent layer, where the urease reaction generates ammonia. The semipermeable membrane allows only ammonia to pass through to the colorforming layer, where it reacts with the indicator to form a dye. The reflection density of the dye is measured and is proportional to the concentration of urea in the sample.
To perform the CREA test, a drop of patient sample is deposited on the slide and is evenly distributed by the spreading layer to the underlying layers. Creatinine diffuses to the reagent layer, where it is hydrolyzed to creatine in the rate-determining step. The creatine is converted to sarcosine and urea by creatine amidinohydrolase. The sarcosine, in the presence of sarcosine oxidase, is oxidized to glycine, formaldehyde, and hydrogen peroxide. The final reaction involves the peroxidase-catalyzed oxidation of a leuco dye to produce a colored product. Following addition of the sample, the slide is incubated. During the initial reaction phase, endogenous creatine in the sample is oxidized. The resulting change in reflection density is measured at 2 time points. The difference in reflection density is proportional to the concentration of creatinine present in the sample.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
Not Found
Indicated Patient Age Range
Not Found
Intended User / Care Setting
Not Found
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
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Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
Method Comparison:
- Study Type: Method Comparison testing followed CLSI Protocol EP09-A3, Measurement Procedure Comparison and Bias Estimation Using Patient Samples.
- Sample Size:
- UREA Serum: 124
- UREA Urine: 128
- CREA Serum: 130
- CREA Urine: 116
- Key Results: The correlation between the predicate and the new tests within the VITROS XT UREA-CREA Slides on the VITROS XT 7600 Integrated System is summarized below.
- UREA Serum: Slope 1.04, Intercept 0.00, Corr. Coeff. 0.999
- UREA Urine: Slope 1.05, Intercept -13.21, Corr. Coeff. 0.999
- CREA Serum: Slope 1.00, Intercept -0.01, Corr. Coeff. 1.000
- CREA Urine: Slope 1.01, Intercept -0.93, Corr. Coeff. 0.998
Precision:
- Study Type: Precision was evaluated with patient pools and quality control materials following CLSI Protocol EP05-A3, Evaluation of Precision Performance of Quantitative Methods; Approved Guideline-Third Edition.
- Sample Size: Minimum of 80 observations (2 replicates per run, 2 runs per day over 20 days) for serum and urine for each fluid ID.
- Key Results: Long term precision analysis showed good repeatability, within day, and within lab precision for UREA nitrogen (serum and urine) and CREA (serum and urine).
Detection Limits:
- Study Type: Detection capability studies were evaluated according to CLSI EP17-A2: Evaluation of Detection Capability for Clinical Laboratory Measurement Procedures.
- Sample Size:
- UREA: 72 LoQ determinations
- CREA Serum: 72 LoQ determinations
- CREA Urine: 64 LoQ determinations
- Key Results:
- UREA Serum: LOB 1.5, LOD 1.7, LOQ 1.7, Claimed LOQ 2.0 mg/dL urea N
- UREA Urine: LOB 23, LOD 27, LOQ 41, Claimed LOQ 67 mg/dL urea N
- CREA Serum: LOB 0.05, LOD 0.07, LOQ 0.11, Claimed LOQ 0.15 mg/dL
- CREA Urine: LOB 1.1, LOD 1.3, LOQ 2.3, Claimed LOQ 3.2 mg/dL
Linearity:
- Study Type: Linearity studies were performed according to CLSI EP06-A, Evaluation of the Linearity of Quantitative Measurement Procedures: A Statistical Approved Guideline (2003).
- Sample Size: A series of twenty proportionally related admixtures of low and high test fluids were tested with each sample tested in quadruplicate.
- Key Results: The linearity studies support the claimed measuring ranges for the individual tests within the VITROS XT UREA-CREA Slides.
- UREA nitrogen Serum/plasma: Measuring Range 2.0-120.0, Linear Range 1.93-148.79 (mg/dL)
- UREA nitrogen Urine: Measuring Range 67 - 2520, Linear Range 62.46-3198.85 (mg/dL)
- CREA Serum/plasma: Measuring Range 0.15-14.0, Linear Range 0.04-14.86 (mg/dL)
- CREA Urine: Measuring Range 3.2-346.5, Linear Range 1.1-418.3 (mg/dL)
Specificity (Interference Testing):
- Study Type: Screened for interfering substances following CLSI document EP07-A3, Interference Testing in Clinical Chemistry.
- Key Results:
- Ammonium ions may cause an increase in measured UREA value.
- UREA Test (Serum): Total protein (12 g/dL) caused -4.3 mg/dL bias at 37 mg/dL urea N. 96 other substances and serum pH at 6.8 and 8.8 were found not to interfere.
- CREA Test (Serum): Creatine, Proline, Bilirubin (conjugated), Dipyrone, Ethamsylate, Glutathione, N-Ethyl glycine, Tolazamide, and Total protein showed biases as listed in the table. 88 other substances and serum pH at 6.8 and 8.8 were found not to interfere.
- UREA Test (Urine): Two urine preservatives containing boric acid interfered. 19 other substances were found not to interfere.
- CREA Test (Urine): 23 substances were found not to interfere.
Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)
See "Summary of Performance Studies" for metrics such as Correlation Coefficient, SD, CV%, LOB, LOD, LOQ, and Bias.
Predicate Device(s): If the device was cleared using the 510(k) pathway, identify the Predicate Device(s) K/DEN number used to claim substantial equivalence and list them here in a comma separated list exactly as they appear in the text. List the primary predicate first in the list.
Reference Device(s): Identify the Reference Device(s) K/DEN number and list them here in a comma separated list exactly as they appear in the text.
Not Found
Predetermined Change Control Plan (PCCP) - All Relevant Information for the subject device only (e.g. presence / absence, what scope was granted / cleared under the PCCP, any restrictions, etc).
Not Found
§ 862.1770 Urea nitrogen test system.
(a)
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.(b)
Classification. Class II.
0
Image /page/0/Picture/0 description: The image shows the logos of the Department of Health & Human Services and the Food and Drug Administration (FDA). The Department of Health & Human Services logo is on the left, and the FDA logo is on the right. The FDA logo includes the text "FDA U.S. FOOD & DRUG ADMINISTRATION" in blue.
March 14, 2019
Ortho-Clinical Diagnostics, Inc. Darlene Phillips Manager, Regulatory Affairs 100 Indigo Creek Drive Rochester, NY 14626
Re: K190326
Trade/Device Name: VITROS XT Chemistry Products UREA-CREA Slides Regulation Number: 21 CFR 862.1770 Regulation Name: Urea nitrogen test system Regulatory Class: Class II Product Code: CDN, JFY Dated: February 15, 2019 Received: February 19, 2019
Dear Darlene Phillips:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and 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) that do not require approval of a premarket approval application (PMA). You mav, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be avare that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's
1
requirements, including, but not limited to: registration and listing (21 CFR Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/CombinationProducts/GuidanceRegulatoryInformation/ucm597488.htm); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm.
For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (http://www.fda.gov/DICE) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely.
Kellie B. Kelm -S
Courtney H. Lias, Ph.D. for Director Division of Chemistry and Toxicology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health
Enclosure
2
Indications for Use
510(k) Number (if known) K190326
Device Name VITROS XT Chemistry Products UREA-CREA Slides
Indications for Use (Describe)
For in vitro diagnostic use only
The UREA test within the VITROS XT Chemistry Products UREA-CREA Slides quantitatively measures urea concentration, reported either as urea nitrogen or as urea (UREA), in serum, plasma, and urine using the VITROS XT 7600 Integrated System. Measurements obtained by this device are used in the diagnosis and treatment of certain renal and metabolic diseases
The CREA test within the VITROS XT Chemistry Products UREA-CREA Slides quantitatively measures creatinine (CREA) concentration in serum, plasma, and urine using the VITROS XT 7600 Integrated System. Creatinine measurements are used in the diagnosis and treatment of renal dialysis, and as a calculation basis for measuring other urine analytes.
Special conditions for use statement: For prescription use only.
| Type of Use (Select one or both, as applicable) |
|---|
| ------------------------------------------------- |
X Prescription Use (Part 21 CFR 801 Subpart D)
Over-The-Counter Use (21 CFR 801 Subpart C)
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3
510(k) Summary
This summary of 510(k) safety and effectiveness information is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92. The assigned 510(k) number is: _k190326
Submitter's Information
Ortho-Clinical Diagnostics, Inc. 100 Indigo Creek Drive Rochester, New York 14626-5101 Phone: (585) 453-4253 Fax: (585) 453-3113
Contact Person:
Darlene J Phillips, RAC Manager, Regulatory Affairs
Date of Preparation: February 12, 2019
Device Proprietary Name(s):
VITROS XT Chemistry Products UREA-CREA Slides
Common Names:
Urea nitrogen assay Creatinine assay
Classification Names
| Test | Product
Code | Class | Regulation Section | Panel |
|------|-----------------|----------|-----------------------------------------------|-----------------------|
| UREA | CDN | Class II | 21 CFR 862. 1770 Urea nitrogen test
system | Clinical
Chemistry |
| CREA | JFY | Class II | 21 CFR 862. 1225 Creatinine test
system | (75) |
Predicate Device(s)
| Predicate Devices | FDA 510(k) Number |
|---|---|
| VITROS Chemistry Products BUN/UREA Slides | K001885 |
| VITROS Chemistry Products CREA Slides | K182063 |
4
Intended Use Statement(s) VITROS XT Chemistry Products UREA-CREA Slides
Rx Only For in vitro diagnostic use only
The UREA test within the VITROS XT Chemistry Products UREA-CREA Slides quantitatively measures urea concentration, reported either as urea nitrogen or as urea (UREA), in serum, plasma, and urine using VITROS XT 7600 Integrated Systems. Measurements obtained by this device are used in the diagnosis and treatment of certain renal and metabolic diseases.
The CREA test within the VITROS XT Chemistry Products UREA-CREA Slides quantitatively measures creatinine (CREA) concentration in serum, plasma, and urine using VITROS XT 7600 Integrated Systems. Creatinine measurements are used in the diagnosis and treatment of renal diseases, in monitoring renal dialysis, and as a calculation basis for measuring other urine analytes.
Device Description
The new device, the VITROS XT Chemistry Products UREA-CREA Slide is a single device that contains both a UREA test and a CREA test multilayered, analytical element coated on a polyester support separated by a plastic barrier sealed within a single slide frame. In this format, individual reactions occur and test results are generated for each analyte independently of the other analyte.
To perform the UREA test, a drop of patient sample is deposited on the slide and is evenly distributed by the spreading layer to the underlying layers. Water and nonproteinaceous components then travel to the underlying reagent layer, where the urease reaction generates ammonia. The semipermeable membrane allows only ammonia to pass through to the colorforming layer, where it reacts with the indicator to form a dye. The reflection density of the dye is measured and is proportional to the concentration of urea in the sample.
To perform the CREA test, a drop of patient sample is deposited on the slide and is evenly distributed by the spreading layer to the underlying layers. Creatinine diffuses to the reagent layer, where it is hydrolyzed to creatine in the rate-determining step. The creatine is converted to sarcosine and urea by creatine amidinohydrolase. The sarcosine, in the presence of sarcosine oxidase, is oxidized to glycine, formaldehyde, and hydrogen peroxide. The final reaction involves the peroxidase-catalyzed oxidation of a leuco dye to produce a colored product. Following addition of the sample, the slide is incubated. During the initial reaction phase, endogenous creatine in the sample is oxidized. The resulting change in reflection density is measured at 2 time points. The difference in reflection density is proportional to the concentration of creatinine present in the sample.
5
Comparison to Predicate Devices
The following tables show similarities and differences between the new and predicate devices. devices:
Summary of the technological characteristics of the device compared to the
T
| Device
Characteristic | New Device
VITROS XT UREA-CREA Slide
(New) | Predícate Devices
VITROS BUN/UREA Slide
[K001885]
VITROS CREA Slide [K182063]
(Current) |
|------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Intended Use | Same for each individual test
For in vitro diagnostic use only.
The UREA test within the VITROS
XT Chemistry Products UREA-
CREA Slides quantitatively
measures urea concentration,
reported either as urea nitrogen
or as urea (UREA), in serum,
plasma, and urine. The CREA
test within the VITROS XT
Chemistry Products UREA-
CREA Slides quantitatively
measures creatinine (CREA)
concentration in serum, plasma,
and urine. | For in vitro diagnostic use only.
VITROS Chemistry Products
BUN/UREA Slides quantitatively
measure urea concentration,
reported either as urea nitrogen
(BUN) or as urea (UREA), in
serum, plasma, and urine.
VITROS Chemistry Products CREA
Slides quantitatively measure
creatinine (CREA) concentration
in serum, plasma, and urine |
| Device
Description | No Change | Multilayered, analytical element
coated on a polyester support |
| Basic Principle | No Change | BUN/UREA
Colorimetric
CREA
Colorimetric
Two point rate |
| Incubation time
and temperature | No Change | Approximately 5 minutes
37°C (98.6° F) |
| Sample type | No Change | Serum, plasma, and urine |
| Summary of the technological characteristics of the device compared to the
predicate device | | |
| Device
Characteristic | New Device
VITROS XT UREA-CREA Slide
(New) | Predícate Devices
VITROS BUN/UREA Slide
[K001885]
VITROS CREA Slide [K182063]
(Current) |
| Amount of Slide
Reactive
Ingredients per
cm² (test) | The composition of the analytical
element of each test within the
VITROS XT Slide will remain
the same as that used in each
predicate device | BUN/UREA
Urease (jack bean) 1.2 U and N-
propyl-4-(2,6-dinitro-4-
chlorobenzyl)-quinolonium
ethane sulfonate (ammonia
indicator)
0.26 mg.
CREA
Creatinine amidohydrolase
(Flavobacterium sp.,) 0.20 U;
creatine amidinohydrolase
(Alcaligenes sp.) 3.6 U; sarcosine
oxidase (Bacillus sp.) 0.55 U;
peroxidase (horseradish root) 1.6
U and 2-(3,5-dimethoxy-4-
hydroxyphenyl)-4,5-bis(4-
dimethylaminophenyl) imidazole
(leuco dye) 32 μg. |
| Assay Range | No Change | BUN/UREA (mg/dL urea N)
Serum/plasma 2.0-120.0
Urine 67–2520
CREA (mg/dL)
Serum/plasma 0.15-14.0
Urine 3.2-346.5 |
| Calibrators | Same | VITROS Chemistry Products
Calibrator Kit 1 |
| Controls | Same | VITROS Chemistry Products
Performance Verifier I and II |
| Differences | | |
| Instrumentation | VITROS XT 7600 Integrated
System | VITROS 250/350, 5,1 FS and 4600
Chemistry Systems
VITROS 5600 and XT 7600
Integrated Systems |
| Sample volume | UREA 4.3 µL
CREA 3.2 µL | BUN/UREA 5.5 µL
CREA 6 µL |
6
4
7
Non-Clinical Testing Analytical Performance
Method Comparison
Method Comparison testing followed CLSI Protocol EP09-A3, Measurement Procedure Comparison and Bias Estimation Using Patient Samples. Serum and urine samples were evaluated on the VITROS XT Chemistry Products UREA-CREA Slides using the VITROS XT 7600 Integrated System and on VITROS Chemistry Products BUN/UREA Slides and VITROS Chemistry Products CREA Slides using the VITROS 5600 Integrated System. The correlation between the predicate and the new tests within the VITROS XT UREA-CREA Slides on the VITROS XT 7600 Integrated System is summarized below.
Summary of Method Comparison Weighted Deming Regression Analysis Data Units mg/dL
| Test | N | Slope | Intercept | Corr.
Coeff. | Test Range | Measuring
range |
|------------|-----|-------|-----------|-----------------|--------------|--------------------|
| UREA Serum | 124 | 1.04 | 0.00 | 0.999 | 3 - 106 | 2.0 - 120.0 |
| UREA Urine | 128 | 1.05 | -13.21 | 0.999 | 105 - 2451 | 67 - 2520 |
| CREA Serum | 130 | 1.00 | -0.01 | 1.000 | 0.20 - 13.49 | 0.15 - 14.0 |
| CREA Urine | 116 | 1.01 | -0.93 | 0.998 | 13.0 - 336.6 | 3.2 - 346.5 |
Precision
Precision was evaluated with patient pools and quality control materials following CLSI Protocol EP05-A3, Evaluation of Precision Performance of Quantitative Methods; Approved Guideline-Third Edition, using the VITROS XT Chemistry Products UREA-CREA Slides on the VITROS XT 7600 Integrated System. The test included a minimum of 80 observations (2 replicates per run, 2 runs per day over 20 days) for serum and urine. The long term precision analysis is summarized below.
The data presented are a representation of test performance and are provided as a guideline. Variables such as sample handling and storage, reagent handling and storage, laboratory environment, and system maintenance can affect reproducibility of test results.
Repeatability (formerly called within-run precision) was determined using two replicates per run. Within Day precision was determined using two runs per day with two replications per run. Within Lab precision was determined using a single lot of slides and a single calibration.
| UREA nitrogen Serum
| Units (mg/dL urea N) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Mean | Repeatability | Within Day | Within Lab | No. | No. | ||||
| Fluid Id | Conc. | SD | CV% | SD | CV% | SD | CV% | of | |
| Obs. | of | ||||||||
| Days | |||||||||
| Pool 1 | 3 | 0.1 | 4.0 | 0.2 | 8.0 | 0.2 | 8.7 | 80 | 20 |
| Pool 2 | 10 | 0.1 | 1.0 | 0.2 | 1.8 | 0.2 | 2.1 | 80 | 20 |
| Native Pool | 11 | 0.1 | 1.2 | 0.2 | 2.1 | 0.2 | 2.1 | 80 | 20 |
| Control 1 | 17 | 0.3 | 1.6 | 0.3 | 1.9 | 0.3 | 1.9 | 80 | 20 |
| Control 2 | 51 | 0.7 | 1.3 | 0.7 | 1.3 | 0.8 | 1.5 | 80 | 20 |
| Pool 3 | 107 | 1.1 | 1.0 | 1.2 | 1.2 | 1.4 | 1.3 | 80 | 20 |
8
| UREA nitrogen Urine | Units (mg/dL urea N) | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Repeatability | Within Day | Within Lab | No. | No. | |||||
| Fluid Id | Mean | ||||||||
| Conc. | SD | CV% | SD | CV% | SD | CV | |||
| % | of | ||||||||
| Obs. | of | ||||||||
| Days | |||||||||
| Pool 1 | 84 | 2.4 | 2.8 | 6.0 | 7.1 | 7.2 | 8.5 | 80 | 20 |
| Native Pool | 293 | 3.8 | 1.3 | 5.4 | 1.8 | 6.8 | 2.3 | 80 | 20 |
| Control 1 | 404 | 4.1 | 1.0 | 7.1 | 1.8 | 9.1 | 2.3 | 80 | 20 |
| Control 2 | 683 | 7.6 | 1.1 | 7.6 | 1.1 | 12.2 | 1.8 | 80 | 20 |
| Pool 2 | 1453 | 14.0 | 1.0 | 19.5 | 1.3 | 19.5 | 1.3 | 80 | 20 |
| Pool 3 | 2331 | 21.4 | 0.9 | 28.2 | 1.2 | 30.6 | 1.3 | 80 | 20 |
| CREA Serum
| Units (mg/dL) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Fluid Id | Mean | Repeatability | Within Day | Within Lab | No. | No. | |||
| Conc. | SD | CV% | SD | CV% | SD | CV% | of | ||
| Obs. | of | ||||||||
| Days | |||||||||
| Pool 1 | 0.66 | 0.007 | 1.1 | 0.008 | 1.2 | 0.011 | 1.7 | 80 | 20 |
| Control 1 | 0.85 | 0.010 | 1.2 | 0.012 | 1.4 | 0.014 | 1.6 | 80 | 20 |
| Native Pool | 0.86 | 0.012 | 1.4 | 0.012 | 1.4 | 0.014 | 1.6 | 80 | 20 |
| Control 2 | 5.41 | 0.030 | 0.6 | 0.040 | 0.7 | 0.084 | 1.6 | 80 | 20 |
| Pool 2 | 9.41 | 0.068 | 0.7 | 0.072 | 0.8 | 0.163 | 1.7 | 80 | 20 |
| Pool 3 | 12.62 | 0.090 | 0.7 | 0.107 | 0.8 | 0.220 | 1.7 | 80 | 20 |
| CREA Urine
| Units (mg/dL) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Mean | Repeatability | Within Day | Within Lab | No. | No. | ||||
| Conc. | SD | CV% | SD | CV% | SD | CV% | of | ||
| Obs. | of | ||||||||
| Days | |||||||||
| Native Pool | 39.0 | 0.26 | 0.7 | 0.37 | 1.0 | 0.52 | 1.3 | 80 | 20 |
| Control 1 | 58.5 | 0.67 | 1.1 | 0.90 | 1.5 | 1.14 | 2.0 | 80 | 20 |
| Control 2 | 137.5 | 1.47 | 1.1 | 2.20 | 1.6 | 3.15 | 2.3 | 80 | 20 |
| Pool 2 | 239.4 | 2.13 | 0.9 | 2.27 | 0.9 | 3.13 | 1.3 | 80 | 20 |
| Pool 3 | 317.2 | 2.00 | 0.6 | 4.13 | 1.3 | 5.44 | 1.7 | 80 | 20 |
Detection Limits
Detection capability studies for the UREA and CREA tests within the VITROS XT UREA-CREA Slides were evaluated according to CLSI EP17-A2: Evaluation of Detection Capability for Clinical Laboratory Measurement Procedures.
The Limit of Quantitation (LoQ) for the UREA test within the VITROS XT UREA-CREA Slides is 2.0 mg/dL for serum/plasma and 67 mg/dL for urine. The total number of LoQ determinations was 72. The Total Error goal used to accept the LoQ was ≤ 1.2 mg/dL for serum and ≤ 21 mg/dL Urea N for urine.
The Limit of Quantitation (LoQ) for the CREA test within the VITROS XT UREA-CREA Slides is 0.15 mg/dL for serum/plasma and 3.2 mg/dL for urine. The total number of LoQ
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determinations was 72 for serum and 64 for urine. The Total Error goal used to accept the LoQ was ≤ 0.06 mg/dL for serum and ≤ 1.2 mg/dL for urine.
| The results of this analysis are summarized below: |
|---|
| UREA (mg/dL urea N) | CREA (mg/dL) | |||
|---|---|---|---|---|
| Serum | Urine | Serum | Urine | |
| LOB | 1.5 | 23 | 0.05 | 1.1 |
| LOD | 1.7 | 27 | 0.07 | 1.3 |
| LOQ | 1.7 | 41 | 0.11 | 2.3 |
| Claimed LOQ | 2.0 | 67 | 0.15 | 3.2 |
Linearity
Linearity studies were performed according to CLSI EP06-A, Evaluation of the Linearity of Quantitative Measurement Procedures: A Statistical Approved Guideline (2003). VITROS XT UREA-CREA Slides were tested on the VITROS XT 7600 Integrated System. A series of twenty proportionally related admixtures of low and high test fluids were tested with to verify linearity of the UREA and CREA serum and urine tests; each sample was tested in quadruplicate. The linearity studies support the claimed measuring ranges for the individual tests within the VITROS XT UREA-CREA Slides.
| Assay | Fluid | Measuring Range
(mg/dL) | Linear Range
(mg/dL) |
|---------------|--------------|----------------------------|-------------------------|
| UREA nitrogen | Serum/plasma | 2.0-120.0 | 1.93-148.79 |
| | Urine* | 67 - 2520 | 62.46-3198.85 |
| CREA | Serum/plasma | 0.15-14.0 | 0.04-14.86 |
| | Urine* | 3.2-346.5 | 1.1-418.3 |
- After multiplying by 21x dilution factor
Serum and plasma samples with values greater than the measuring range may be diluted up to a maximum dilution of 1 part sample with 1 part diluent. A 7% BSA solution was found to be an acceptable diluent for serum and plasma specimens assaved using VITROS XT Chemistry Products UREA-CREA Slides.
Urine samples with values greater than the measuring range may be diluted up to a maximum dilution of 1 part sample with 1 part diluent. Isotonic saline and reagent-grade water were both found to be acceptable diluents for UREA urine specimens assayed using the VITROS XT Chemistry Products UREA-CREA Slides. Reagent-grade water was found to be an acceptable diluent for CREA urine specimens assayed using the VITROS XT Chemistry Products UREA-CREA Slides.
Expected Values
The expected values of the UREA and CREA tests within the VITROS XT UREA-CREA Slides are the not changed from those of the predicate assays. Each laboratory should confirm the validity of these intervals for the population it serves.
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UREA Reference Interval
The serum reference interval is the central 95% of results from an internal study of 3160 apparently healthy adults from a working population (612 females and 2548 males).
The urine reference interval is based on an external study.
| UREA Reference Interval | |
|---|---|
| Serum | |
| Male | 9-20 mg/dL urea N |
| Female | 7-17 mg/dL urea N |
| Urine | |
| 24-hour | 12-20 g urea N /day* |
- Urea nitrogen concentration (mg/dL) x 24-hour volume (dL) = mg/day.
CREA Reference Interval
The serum reference intervals are the central 95% of results from an external study of apparently healthy adults (serum: 180 males and 180 females).
The urine reference intervals are based on a separate external study.
| CREA Reference Interval | |
|---|---|
| Serum | |
| Male | 0.66–1.25 mg/dL |
| Female | 0.52–1.04 mg/dL |
| Urine | |
| Male | 1000–2000 mg/day* |
| Female | 800–1800 mg/day* |
- Creatinine concentration (mg/dL) x 24-hour volume (dL) = mg/day.
Specificity
The UREA and CREA tests within the VITROS XT Chemistry Products UREA-CREA Slide were screened for interfering substances following CLSI document EP07-A3, Interference Testing in Clinical Chemistry. The supplemental tables in CLSI document EP37 were referenced for recommended testing concentrations for analytes and endogenous substances that may interfere in clinical chemistry measurement procedures.
Point estimates of the effects of potential interferents on VITROS XT UREA-CREA Slides were made using the paired difference method. Dose-response analysis was conducted to characterize the degree of interference for each substance, and expected bias was reported at the lowest test level which did not meet acceptance criteria for bias as shown in the product claims.
Known Interferences
Ammonium ions may cause an increase in measured UREA value equivalent to the specimen's nitrogen content.
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Serum and Plasma
The substances listed in the table, when tested at the concentrations indicated, caused the bias shown. The bias is an estimate of the maximum bias observed.
It is possible that other interfering substances may be encountered. These results are representative; however, your results may differ somewhat due to test-to-test variation. The degree of interference at concentrations other than those listed might not be predictable.
UREA Test
| Interferent | Interferent
Concentration | Urea nitrogen
Concentration | Bias |
|---------------|------------------------------|--------------------------------|------------|
| Total protein | 12 g/dL | 37 mg/dL | -4.3 mg/dL |
Ninety-six (96) test substances, when tested at the concentrations indicated, as well as serum pH at 6.8 and 8.8, were found not to interfere, bias