(35 days)
Not Found
No
The device description and performance studies focus on chemical reactions and visual interpretation of color changes, with no mention of AI or ML technologies.
No
This device is for in vitro diagnostic use, meaning it measures substances in urine to aid in diagnosis, not to treat or directly manage a condition in a living organism.
Yes
Explanation: The "Intended Use / Indications for Use" section explicitly states that the device is used "to aid in the diagnosis of metabolic disorders, kidney function anomalies and urinary tract infections" and "liver function" by measuring various substances in urine. This directly aligns with the definition of a diagnostic device.
No
The device description explicitly states it is a urine test strip with reagent pads affixed to plastic strips, which are physical hardware components. The results are visually read by comparing the strip to a color chart, indicating a manual process, not a software-driven analysis.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Intended Use/Indications for Use: The document explicitly states the device is "intended for the in vitro measurement of the following in urine" and "intended for prescription, in vitro diagnostic use only". This directly aligns with the definition of an in vitro diagnostic device, which is used to examine specimens from the human body to provide information for diagnosis, monitoring, or treatment.
- Device Description: The device works by reacting with analytes in urine specimens, producing a visible color change that is then interpreted. This is a classic method used in many IVD tests.
- Intended User / Care Setting: The indication for "prescription, in vitro diagnostic use only" further reinforces its classification as an IVD.
- Performance Studies: The document describes performance studies like method comparison, precision, linearity, detection limit, and analytical specificity, which are standard types of studies conducted for IVD devices to demonstrate their analytical performance.
- Predicate Device: The mention of a predicate device (MULTISTIX 10 SG) which is also a urine test strip, suggests that this device is being compared to an existing IVD on the market.
All these factors strongly indicate that this device is an In Vitro Diagnostic.
N/A
Intended Use / Indications for Use
DUS 2GP Reagent Strips, DUS 5 Reagent Strips, DUS 10 Reagent Strips
This device is intended for the in vitro measurement of the following in urine: Leukocyte, Nitrite, Urobilinogen, Protein, pH, Blood, Specific gravity, Ketone, Bilirubin, Glucose. These strips are intended for prescription, in vitro diagnostic use only and they are visually read.
DUS 2GP reagent strips provide qualitative and semiquantitative measurements for protein, and glucose in urine specimens. Test results may provide information regarding the status of carbohydrate metabolism and kidney function.
DUS 5 reagent strips provide qualitative and semiquantitative measurements for leukocytes, nitrite, blood , protein, and glucose in urine specimens. These measurements are used to aid in the diagnosis of metabolic disorders, kidney function anomalies and urinary tract infections.
DUS 10 reagent strips provide qualitative and semiquantitative measurements for specific gravity, pH, leukocytes, nitrite, protein, glucose, ketone, urobilinogen, bilirubin and blood in urine speciments are used to aid in the diagnosis of metabolic disorders, kidney function anomalies, urinary tract infections and liver function.
Product codes (comma separated list FDA assigned to the subject device)
JIL, JIO, JIR, LJX, JMT, CDM, CEN, JRE, JIN, JJB
Device Description
The DUS Series are urine test strips with different reagent pads for the determination of specific gravity, pH, leukocytes, nitrite, protein, glucose, ketone, urobilinogen, bilirubin and blood affixed onto plastic strips. of which leukocyte, nitrite, urobilinogen, protein, pH, blood, specific gravity, ketone, bilirubin and glucose reagent pads are affixed onto the plastic strips. The reagent pads react with analytes in the urine giving a visible color. Results are confirmed by comparison of the test strip with the color chart on the container. For each color result for each analyte, a semiquantitative value is available on the box label (e.g. bilirubin results include negative, 1, 2, and 4 mg/dL) and the associated qualitative result (e.g. bilirubin results include negative. +, ++, +++).
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
prescription, in vitro diagnostic use only
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
Not Found
Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
1. Performance Characteristics
The DUS 10 reagent strips were used for all analytical studies.
- a) Precision/Reproducibility
- Study Type: Precision/Reproducibility testing in accordance with CLSI EP5-A3.
- Sample Size:
- Within-run: 10 test strips from 3 different lots at 3 sites (30 tests per site = 90 replicates per level) for each of 2 levels of control solutions.
- Within-day: 1 test strip per day from 3 different lots at 3 sites for 10 days (30 tests per site = 90 replicates per level) for each of 2 levels of control solutions.
- Key Results: High exact agreement and agreement within +/- one block were observed for all analytes across both levels of control solutions for both within-run and within-day precision studies. Most measurements showed 100% agreement, with a few instances slightly below (e.g., SG at 98.9% exact agreement within-run for Level 2, pH at 98.9% exact agreement within-day for Level 2).
- b) Linearity /assay reportable range.
- Study Type: Linearity / assay reportable range evaluation.
- Sample Size: Samples were created at various concentrations, and each concentration level was tested in 10 replicates with 3 lots of test strips (90 replicates per concentration).
- Key Results: High exact match percentages (mostly 100% or high 90s) were observed across the tested concentration ranges for all analytes, demonstrating linearity and reportable range capability.
- c) Detection limit
- Study Type: Sensitivity study to evaluate limits of detection.
- Sample Size: For each analyte, 3 levels across the measuring range were tested, with 90 replicates per concentration (30 times using 3 reagent strip lots).
- Key Results: Sensitivity was defined as the cutoff for which ≥95% of contrived pooled measurements were trace or the first positive result. For all analytes, 100% positive agreement was achieved at or slightly above the defined detection limits (e.g., Urobilinogen 2 mg/dL, Glucose 100 mg/dL, Bilirubin 1.0 mg/dL, Ketones 5 mg/dL, Blood 10 RBC/μL, Protein 15 mg/dL, Nitrite 0.05 mg/dL, Leukocytes 15 WBC/μL).
- d) Analytical specificity
- Study Type: Evaluation of potential interferents and drugs.
- Sample Size: Urine sample pools at 3 analyte concentrations (negative, low positive, high positive) were spiked with potential interfering substances and analyzed in 3 replicates using 3 lots of DUS 10 test strips.
- Key Results: A table lists substances that did not cause interference at evaluated concentrations. Another table lists substances that did interfere with one or more analytes, showing the lowest concentration at which interference was observed and the resulting change in color block output (typically +/- 1 color block). The labeling also includes limitations addressing these interferences.
2. Method Comparison study
- Study Type: Method comparison study comparing the DUS 10 test strips to the predicate device (Multistix 10 SG).
- Sample Size: A total of 867 fresh urine samples.
- Data Source: Samples obtained at three clinical sites.
- Key Results: Results are presented in tables for each analyte showing agreement between the new device and the predicate device. For most analytes and concentration ranges, exact agreement was high (typically >90%), and agreement within 1 color block was 100%. This indicates substantial concordance between the new device and the predicate.
Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)
- Precision/Reproducibility: Exact agreement and agreement within +/- one block (%).
- Linearity/Assay Reportable Range: % Exact match.
- Detection Limit: Positive Agreement (%).
- Method Comparison: Exact agreement (%), Agreement within 1 block (%).
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.
K992257 / MULTISTIX 10 SG
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
§ 862.1340 Urinary glucose (nonquantitative) test system.
(a)
Identification. A urinary glucose (nonquantitative) test system is a device intended to measure glucosuria (glucose in urine). Urinary glucose (nonquantitative) measurements are used in the diagnosis and treatment of carbohydrate metabolism disorders including diabetes mellitus, hypoglycemia, and hyperglycemia.(b)
Classification. Class II.
0
Image /page/0/Picture/0 description: The image contains 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 is a blue square with the letters "FDA" in white, followed by the words "U.S. FOOD & DRUG ADMINISTRATION" in blue.
May 23, 2018
DFI Co., Ltd. % Ho Dong Yang, CEO Onbix Corporation #821 Samil Plaza, 14, Dogok-ro 1-Gil, Gangnam-gu Seoul, 06523 Korea
Re: K181024
Trade/Device Name: DUS 2GP Reagent Strips, DUS 5 Reagent Strips, DUS 10 Reagent Strips Regulation Number: 21 CFR 862.1340 Regulation Name: Urinary glucose (nonguantitative) test system Regulatory Class: Class II Product Code: JIL, JIO, JIR, LJX, JMT, CDM, CEN, JRE, JIN, JJB Dated: April 11, 2018 Received: April 18, 2018
Dear Ho Dong Yang:
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 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. 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 requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801 and Part 809); medical device reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR
1
Part 820); 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 the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.
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
for Courtney H. Lias, Ph.D. 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) K181024
Device Name
DUS 2GP Reagent Strips, DUS 5 Reagent Strips, DUS 10 Reagent Strips
Indications for Use (Describe)
DUS 2GP Reagent Strips, DUS 5 Reagent Strips, DUS 10 Reagent Strips
This device is intended for the in vitro measurement of the following in urine: Leukocyte, Nitrite, Urobilinogen, Protein, pH, Blood, Specific gravity, Ketone, Bilirubin, Glucose. These strips are intended for prescription, in vitro diagnostic use only and they are visually read.
DUS 2GP reagent strips provide qualitative and semiquantitative measurements for protein, and glucose in urine specimens. Test results may provide information regarding the status of carbohydrate metabolism and kidney function.
DUS 5 reagent strips provide qualitative and semiquantitative measurements for leukocytes, nitrite, blood , protein, and glucose in urine specimens. These measurements are used to aid in the diagnosis of metabolic disorders, kidney function anomalies and urinary tract infections.
DUS 10 reagent strips provide qualitative and semiquantitative measurements for specific gravity, pH, leukocytes, nitrite, protein, glucose, ketone, urobilinogen, bilirubin and blood in urine speciments are used to aid in the diagnosis of metabolic disorders, kidney function anomalies, urinary tract infections and liver function.
| Type of Use (Select one or both, as applicable) | |
|---|---|
| ☑ Prescription Use (Part 21 CFR 801 Subpart D) | □ Over-The-Counter Use (21 CFR 801 Subpart C) |
CONTINUE ON A SEPARATE PAGE IF NEEDED.
This section applies only to requirements of the Paperwork Reduction Act of 1995.
DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.
The burden time for this collection of information is estimated to average 79 hours per response, including the time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:
Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff PRAStaff(@fda.hhs.gov
"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."
3
510(k) SUMMARY [K181024]
This 510(k) summary is being submitted in accordance with the requirements of 21 CFR §807.92.
| Submitter Information: | DFI Co., Ltd.
388-25, Gomo-ro, Jillye-myeon, Gimhae-si,
Gyeongsangnam-do, 621-881, Korea
Tel. +82-55-346-1882 Fax: +82-55-346-1883 |
|------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Contact Person: | Ho Dong, Yang
Onbix Corporation
#821 Samil Plaza, 14, Dogokro 1-gil Gangnam-gu
Seoul, Korea (06253)
Tel: *82-2-566-3360 / Fax: *82-2-6280-3360
Email: onbix@naver.com |
Date Summary Prepared: May 17, 2018
| Device Information: | |
|---|---|
| Trade Name(s): | DUS 2GP Reagent Strips, DUS 5 Reagent Strips, DUS 10 Reagent Strips |
| Common Name: | urinary test system |
| Panel: | clinical chemistry |
Regulatory information
| Name | Regulation | Product
code | Device
class |
|-----------------------------------------------------------------------|-----------------|-----------------|-----------------|
| Urinary Glucose
(non-quantitative) test system | 21 CFR 862.1340 | JIL | II |
| Occult Blood test | 21 CFR 864.6550 | JIO | II |
| Urinary Protein or Albumin
(nonquantitative) test system | 21 CFR 862.1645 | JIR | I |
| Leukocyte peroxidase test | 21 CFR 864.7675 | LJX | I |
| Nitrite (nonquantitative) test system | 21 CFR 862.1510 | JMT | I |
| Urinary Urobilinogen
(nonquantitative) test system | 21 CFR 862.1785 | CDM | I |
| Urinary pH (nonquantitative) test | 21 CFR 862.1550 | CEN | I |
| Specific Gravity | 21CFR 862.2800 | JRE | I |
| Ketones (nonquantitative) test
system | 21 CFR 862.1435 | JIN | I |
| Urinary Bilirubin and its conjugates
(nonquantitative) test system | 21 CFR 862.1115 | JJB | I |
4
Predicate Device Information:
K992257 / MULTISTIX 10 SG
Device Description:
DUS 2GP Reagent Strips, DUS 5 Reagent Strips, DUS 10 Reagent Strips
The DUS Series are urine test strips with different reagent pads for the determination of specific gravity, pH, leukocytes, nitrite, protein, glucose, ketone, urobilinogen, bilirubin and blood affixed onto plastic strips. of which leukocyte, nitrite, urobilinogen, protein, pH, blood, specific gravity, ketone, bilirubin and glucose reagent pads are affixed onto the plastic strips. The reagent pads react with analytes in the urine giving a visible color. Results are confirmed by comparison of the test strip with the color chart on the container. For each color result for each analyte, a semiquantitative value is available on the box label (e.g. bilirubin results include negative, 1, 2, and 4 mg/dL) and the associated qualitative result (e.g. bilirubin results include negative. +. ++, +++).
Indications for Use:
This device is intended for the in vitro measurement of the following in urine: Leukocyte, Nitrite, Urobilinogen, Protein, pH, Blood, Specific gravity, Ketone, Bilirubin, Glucose. These strips are intended for prescription, in vitro diagnostic use only and they are visually read.
DUS 2GP reagent strips provide qualitative and semiquantitative measurements for protein and glucose in urine specimens. Test results may provide information regarding the status of carbohydrate metabolism and kidney function.
DUS 5 reagent strips provide qualitative and semiquantitative measurements for leukocytes, nitrite, blood, protein, and glucose in urine specimens. These measurements are used to aid in the diagnosis of metabolic disorders and kidney function anomalies and urinary tract infections.
DUS 10 reagent strips provide qualitative and semiquantitative measurements for specific gravity, pH. leukocytes, nitrite, protein, glucose, ketone, urobilinogen, bilirubin a n d blood in urine specimens. These measurements are used to aid in the diagnosis of metabolic disorders, kidney function anomalies, urinary tract infections and liver function.
Comparison to Predicate Device(s):
This device is equivalent to the predicate devices in its intended use and technological characteristics, including:
indications for use technological characteristics performance properties
Summary of testing:
The performance characteristics of the candidate strips were verified by method comparison, precision, detection limit, interference and specificity studies.
Testing is summarized below.
5
1. Performance Characteristics
DUS 10 reagent strips were used for all analytical studies, because DUS 2GP and DUS 5 reagent strips contain subsets of the analytes in the DUS 10 reagent strips.
a) Precision/Reproducibility
Precision testing was done in accordance with CLSI EP5-A3.. The repeatability/ reproducibility were determined at three clinical sites, using commercially available control solutions. Studies were performed by medical technicians, using 2 levels of commercially available urine based control solutions. For within-run precision studies, 10 test strips from 3 different lots at 3 sites were tested (30 tests at each site = 90 replicates per level). For within-day precision studies, 1 test strip a day from 3 different lots was tested at 3 sites for 10 days (30 tests at each site = 90 replicates per level). The results are summarized below:
| Level 1 control | |||||
|---|---|---|---|---|---|
| Within-run (n=90) | Within-day (n=90) | ||||
| Item | Test Results | Exact | |||
| agreement | |||||
| (%) | Agreement | ||||
| within | |||||
| +/-one | |||||
| block(%) | Exact | ||||
| agreement | |||||
| (%) | Agreement | ||||
| within | |||||
| +/-one | |||||
| block(%) | |||||
| Urobilinogen | Normal | 100 | 100 | 100 | 100 |
| Glucose | Negative | 100 | 100 | 100 | 100 |
| Bilirubin | Negative | 100 | 100 | 100 | 100 |
| Ketones | Negative | 100 | 100 | 100 | 100 |
| SG | 1.020 | 100 | 100 | 100 | 100 |
| Blood | Negative | 100 | 100 | 100 | 100 |
| pH | 6 | 100 | 100 | 100 | 100 |
| Protein | Negative | 100 | 100 | 100 | 100 |
| Nitrite | Negative | 100 | 100 | 100 | 100 |
| Leukocytes | Negative | 100 | 100 | 100 | 100 |
| Level 2 control | |||||
|---|---|---|---|---|---|
| Within-run (n=90) | Within-day (n=90) | ||||
| Item | Test Results | Exact | |||
| agreement | |||||
| (%) | Agreement | ||||
| within | |||||
| +/-one | |||||
| block(%) | Exact | ||||
| agreement | |||||
| (%) | Agreement | ||||
| within | |||||
| +/-one | |||||
| block(%) | |||||
| Urobilinogen | 4mg/dL | 100 | 100 | 100 | 100 |
| Glucose | 1000mg/dL | 100 | 100 | 100 | 100 |
| Bilirubin | 4mg/dL | 100 | 100 | 100 | 100 |
| Ketones | 40mg/dL | 100 | 100 | 100 | 100 |
| SG | 1.020 | 98.9 | 100 | 100 | 100 |
| Blood | 200 RBC/uL | 100 | 100 | 100 | 100 |
| pH | 7 | 100 | 100 | 98.9 | 100 |
| Protein | 100 mg/dL | 100 | 100 | 100 | 100 |
| Nitrite | Pos | 100 | 100 | 100 | 100 |
| Leukocytes | 70 WBC/uL | 100 | 100 | 100 | 100 |
6
b) Linearity /assay reportable range.
Linearity / assay reportable range was evaluated in-house. Samples were created by spiking known concentration of each standard material or by serial dilution of a high concentration urine sample with negative urine. Testing was performed by 3 medical technicians using 3 lots of test strips. Each concentration level was tested in 10 replicates with each lot of test strips. The results are summarized below:
| Analyte | Urine sample
concentration | Color block
output | % Exact match |
|------------------|-------------------------------|-----------------------|----------------|
| Urobilinogen | Negative/Norm | 0.1 | 100 % (90/90) |
| | 1 mg/dL | 1 mg/dL | 100 % (90/90) |
| | 2 mg/dL | 2 mg/dL | 97.7 % (88/90) |
| | 4 mg/dL | 4 mg/dL | 98.8 % (89/90) |
| | 8 mg/dL | 8 mg/dL | 98.8 % (89/90) |
| Glucose | Negative | Neg. | 100 % (90/90) |
| | 100 mg/dL | ±(100 mg/dL) | 100 % (90/90) |
| | 250 mg/dL | +(250 mg/dL) | 97.7 % (88/90) |
| | 500 mg/dL | ++(500 mg/dL) | 98.8 % (89/90) |
| | 1000 mg/dL | +++(1000 mg/dL) | 97.7 % (88/90) |
| | 2000 mg/dL | ++++(2000
mg/dL) | 100 % (90/90) |
| Bilirubin | Negative | Neg. | 100 % (90/90) |
| | 1 mg/dL | + | 98.8 % (89/90) |
| | 2 mg/dL | ++ | 96.6 % (87/90) |
| | 4 mg/dL | +++ | 100 % (90/90) |
| Ketones | Negative | Neg. | 100 % (90/90) |
| | 5 mg/dL | ±(5 mg/dL) | 100 % (90/90) |
| | 15 mg/dL | +(15 mg/dL) | 97.7 % (88/90) |
| | 40 mg/dL | ++(40 mg/dL) | 98.8 % (89/90) |
| | 80 mg/dL | +++(80 mg/dL) | 98.8 % (89/90) |
| 160 mg/dL | ++++(160 mg/dL) | 100 % (90/90) | |
| Analyte | Urine sample
concentration | Color block
output | % Exact match |
| Specific gravity | 1.000 | 1.000 | 100 % (90/90) |
| | 1.005 | 1.005 | 94.4 % (85/90) |
| | 1.010 | 1.010 | 100 % (90/90) |
| | 1.015 | 1.015 | 96.6 % (87/90) |
| | 1.020 | 1.020 | 97.7 % (88/90) |
| | 1.025 | 1.025 | 96.6 % (87/90) |
| | 1.030 | 1.030 | 100 % (90/90) |
| Nitrite | Negative | Neg. | 100% (90/90) |
| | 0.05 mg/dL | Trace | 100 % (90/90) |
| | 10 mg/dL | Pos | 100 % (90/90) |
| Blood | Negative | Neg. | 100 % (90/90) |
| | 10 RBC/μL | Trace | 100 % (90/90) |
| | 25 RBC/μL | +(25 RBC/μL) | 98.8 % (89/90) |
| | 80 RBC/μL | ++(80 RBC/μL) | 100 % (90/90) |
| | 200 RBC/μL | +++(200RBC/μL) | 100 % (90/90) |
| pH | 5 | 5 | 100 % (90/90) |
| | 6 | 6 | 98.8 % (89/90) |
| | 6.5 | 6.5 | 98.8 % (89/90) |
| | 7 | 7 | 97.7 % (88/90) |
| | 7.5 | 7.5 | 97.7 % (88/90) |
| | 8 | 8 | 98.8 % (89/90) |
| | 8.5 | 8.5 | 100% (90/90) |
| Protein | Negative | Neg. | 100 % (90/90) |
| | 15 mg/dL | Trace | 98.8 % (89/90) |
| | 30 mg/dL | +(30 mg/dL) | 98.8 % (89/90) |
| | 100 mg/dL | ++(100 mg/dL) | 96.6 % (87/90) |
| | 300 mg/dL | +++(300 mg/dL) | 97.7 % (88/90) |
| | 100 mg/dL | +++++(1000 mg/dL) | 100 % (90/90) |
| Leukocytes | Negative | Neg. | 100 % (90/90) |
| | 15 WBC/μL | Trace | 100 % (90/90) |
| | 70 WBC/μL | +(70 WBC/μL) | 97.7 % (88/90) |
| | 125 WBC/μL | ++(125 WBC/μL) | 97.7 % (88/90) |
| | 500 WBC/μL | +++(500 WBC/μL) | 100 % (90/90) |
7
8
c) Detection limit
A sensitivity study was performed to evaluate the limits of detection for each of the analytes. Negative urine was spiked with standard materials to obtain 3 levels across the measuring range for each analyte concentration. 90 replicates were obtained for each concentration (each sample concentration was analyzed 30 times using 3 reagent strip lots). Sensitivity was defined as the cutoff for which ≥95% of the contrived pooled measurements were trace or the first positive result.
| Urobilinogen | |||
|---|---|---|---|
| Conc. | Negative | Positive | |
| (+ 2mg/dL) | Positive Agreement | ||
| (%) | |||
| 1.8 mg/dL | 8 | 82 | 91.1% |
| 2 mg/dL | 0 | 90 | 100% |
| 2.3 mg/dL | 0 | 90 | 100% |
| Result cut off | 2 mg/dL |
| Glucose | |||
|---|---|---|---|
| Conc. | Negative | Positive | Positive Agreement |
| (± 100mg/dL) | (%) | ||
| 80 mg/dL | 5 | 85 | 94.4% |
| 100 mg/dL | 0 | 90 | 100% |
| 120 mg/dL | 0 | 90 | 100% |
| Result cut off | 100mg/dL |
| Bilirubin | |||
|---|---|---|---|
| Conc. | Negative | Positive | |
| (+ 1.0mg/dL) | Positive Agreement | ||
| (%) | |||
| 0.8 mg/dL | 6 | 84 | 93.3% |
| 1.0 mg/dL | 0 | 90 | 100% |
| 1.2 mg/dL | 0 | 90 | 100% |
| Result cut off | 1.0 mg/dL |
9
| Ketones | |||
|---|---|---|---|
| Conc. | Negative | Positive | Positive Agreement |
| (± 5mg/dL) | (%) | ||
| 4 mg/dL | 5 | 85 | 94.4% |
| 5 mg/dL | 0 | 90 | 100% |
| 6 mg/dL | 0 | 90 | 100% |
| Result cut off | 5 mg/dL |
| Blood | |||
|---|---|---|---|
| Positive | Positive Agreement | ||
| Conc. | Negative | (±5 RBC/μL) | (%) |
| 8 RBC/μL | 7 | 83 | 92.2% |
| 10 RBC/μL | 0 | 90 | 100% |
| 12 RBC/μL | 0 | 90 | 100% |
| Result cut off | 10 RBC/μL |
| Protein | |||
|---|---|---|---|
| Negative | Positive | ||
| (±15 mg/dL) | Positive Agreement | ||
| (%) | |||
| Conc. | |||
| 12mg/dL | 6 | 84 | 93.3% |
| 15mg/dL | 0 | 90 | 100% |
| 18mg/dL | 0 | 90 | 100% |
| Result cut off | 15mg/dL |
| Nitrite | |||
|---|---|---|---|
| Positive | Positive Agreement | ||
| Conc. | Negative | (0.05 mg/dL) | (%) |
| 0.04mg/dL | 6 | 84 | 93.3% |
| 0.05mg/dL | 0 | 90 | 100% |
| 0.06mg/dL | 0 | 90 | 100% |
| Result cut off | 0.05mg/dL |
10
| Leukocytes | |||
|---|---|---|---|
| Conc. | Negative | Positive | |
| (Trace | |||
| 15WBC/μL) | Positive Agreement | ||
| (%) | |||
| 12 WBC/μL | 5 | 85 | 94.4% |
| 15 WBC/μL | 0 | 90 | 100% |
| 18WBC/μL | 0 | 90 | 100% |
| Result cut off | 15 WBC/μL |
The reportable ranges for each analyte are summarized below:
| Test | Reportable Range |
|---|---|
| Urobilinogen | Qualitative: normal to 3+ |
| Semi-quantitative: 0.1 to 8 mg/dL | |
| Glucose | Qualitative: Negative to 4+ |
| Semi-quantitative : Negative to 2000 mg/dL | |
| Bilirubin | Qualitative: Negative to 3+ |
| Semi-quantitative : Negative to 4 mg/dL | |
| Ketones | Qualitative: Negative to 4+ |
| Semi-quantitative : Negative to 160 mg/dL | |
| Specific Gravity | Semi-quantitative : 1.000 to 1.030 |
| Blood | Qualitative: Negative to 3+ |
| Semi-quantitative : Negative to 200 RBC/ μL | |
| pH | Semi-quantitative : 5 to 8.5 |
| Protein | Qualitative: Negative to 4+ |
| Semi-quantitative : Negative to 1000 mg/dL | |
| Nitrite | Qualitative: Negative to Pos |
| Semi-quantitative : Negative to 10 mg/dL | |
| Leukocytes | Qualitative: Negative to 3+ |
| Semi-quantitative : Negative to 500 WBC/μL |
11
d) Analytical specificity
Potential interferents and drugs were evaluated to assess their interfering effect on the performance of DUS 10 test strips. Urine sample pools prepared at 3 analyte concentrations (negative, low positive and high positive) were spiked with potential interfering substances at various interference concentrations and analyzed in 3 replicates using 3 lots of DUS 10 test strips. Interference was defined as change in output of ±1 color block between the spiked and unspiked control sample. No interference was observed for the following compounds at the concentrations evaluated below:
| Potential Interfering Substance | Highest concentration at which
no interference was observed |
|----------------------------------|----------------------------------------------------------------|
| Albumin (protein) | 750 mg/dL |
| Ascorbic acid | 15 mg/dL |
| Acetaminophen | 25 mg/dL |
| Azo gantrinsin (Sulfamethoxazol) | 140 mg/dL |
| Bilirubin | 3 mg/dL |
| Captropril | 100 mg/dL |
| Sodium hypochlorite | 0.1% |
| Creatinine | 800 mg/dL |
| Nitrofurantoin | 10 mg/dL |
| Oxalic acid | 30 mg/dL |
| p-amino Salicylic acid | 375 mg/dL |
| β-D-Glucose (Glucose) | 1000 mg/dL |
| Phenazopyridine | 25 mg/dL |
| Riboflavin | 12 mg/dL |
| Selenium | 150 mg/dL |
| Forrmaldehyde | 100 mg/dL |
| Hemoglobin | 3 mg/dL |
| Lithium acetoacetate (ketones) | 20 mg/dL |
| Tetracycline | 20 mg/dL |
| Urobilinogen | 10 mg/dL |
| pH | 7 |
| Specific gravity | 1.030 |
The following table shows the substances that did interfere with one more of the analytes tested with the DUS 10 test strips. Results are expressed as the lowest concentration of interfering substances that exhibit interference and the resulting change in output of color block:
12
| Analyte | Potential Interfering
Substance | Concentration at which
Interference was
observed | Change in
color block
output |
|------------------|-------------------------------------|--------------------------------------------------------|------------------------------------|
| Urobilinogen | Azo gantrinsin
(Sulfamethoxazol) | ≥105mg/dL | +1 |
| | Bilirubin | ≥4mg/dL | +1 |
| | Formaldehyde | ≥150mg/dL | -1 |
| | Nitrofurantoin | ≥40mg/dL | +1 |
| | p-Amino salicylic acid | ≥750mg/dL | +1 |
| | Phenazopyridine | ≥37mg/dL | +1 |
| | Riboflavin | ≥25mg/dL | +1 |
| | Selenium | ≥220mg/dL | +1 |
| Glucose | Ascorbic Acid | ≥40mg/dL | -1 |
| | Bilirubin | ≥6mg/dL | +1 |
| | Chlorine Bleach | ≥1% | +1 |
| | Formaldehyde | ≥150mg/dL | +1 |
| | Lithium | ≥40mg/dL | -1 |
| | NaCl (Specific gravity) | ≤1.000 | +1 |
| Bilirubin | Ascorbic Acid | ≥40mg/dL | -1 |
| | p-Amino salicylic acid | ≥1500mg/dL | +1 |
| | Phenazopyridine | ≥37mg/dL | +1 |
| | Selenium | ≥220mg/dL | +1 |
| Ketones | Bilirubin | ≥4mg/dL | +1 |
| | Captopril | ≥150mg/dL | +1 |
| | NaCl (Specific gravity) | ≥1.040 | +1 |
| Blood | Albumin | ≥1000mg/dL | -1 |
| | Ascorbic Acid | ≥30mg/dL | -1 |
| | Bilirubin | ≥6mg/dL | +1 |
| | Captopril | ≥150mg/dL | -1 |
| | Chlorine Bleach | ≥0.5% | +1 |
| | Formaldehyde | ≥150mg/dL | +1 |
| | NaCl (Specific gravity) | ≥1.040 | -1 |
| | Nitrofurantoin | ≥30mg/dL | +1 |
| | Riboflavin | ≥50mg/dL | +1 |
| | Urobilinogen | ≥20mg/dL | -1 |
| pH | - | - | - |
| Specific Gravity | pH | >8 | +1 |
| | | | |
| Protein | Acetaminophen | 50mg/dL | +1 |
| | Bilirubin | ≥6mg/dL | +1 |
| | Hemoglobin | ≥5mg/dL | +1 |
| | Nitrofurantoin | ≥20mg/dL | +1 |
| | Riboflavin | ≥25mg/dL | -1 |
| | Urobilinogen | ≥20mg/dL | -1 |
| | pH | ≥9 | +1 |
| Nitrite | Ascorbic Acid | ≥40mg/dL | -1 |
| | Bilirubin | ≥4mg/dL | +1 |
| | Nitrofurantoin | ≥20mg/dL | +1 |
| | Phenazopyridine | ≥37mg/dL | +1 |
| | Riboflavin | ≥50mg/dL | +1 |
| | Selenium | ≥300mg/dL | +1 |
| | Urobilinogen | ≥15mg/dL | +1 |
| Leukocytes | Albumin | ≥1000mg/dL | -1 |
| | Bilirubin | ≥4mg/dL | +1 |
| | Captopril | ≥150mg/dL | -1 |
| | Chlorine Bleach | ≥0.5% | +1 |
| | Formaldehyde | ≥150mg/dL | +1 |
| | NaCl (Specific gravity) | ≥1.040 | -1 |
| | Nitrofurantoin | ≥30mg/dL | +1 |
| | Oxalic Acid | ≥45mg/dL | -1 |
| | Glucose | ≥1500mg/dL | -1 |
| | Phenazopyridine | ≥50mg/dL | +1 |
| | Riboflavin | ≥37mg/dL | +1 |
| | Selenium | ≥300mg/dL | +1 |
| | Tetracycline | ≥40mg/dL | -1 |
| | Urobilinogen | >15mg/dL | +1 |
13
14
The labeling includes the following limitations to address the interferences observed:
As with all laboratory tests, definitive diagnostic or therapeutic decisions should not be based on any single result of method. Substances that cause abnormal urine color may affect the readability of test pads in urinalysis reagent strips.
Urinary ascorbic acid concentrations as low as 40mg/dl can cause interference in specimens with low concentrations of glucose, blood, nitrite and bilirubin
Urobilinogen: The absence of urobilinogen in the specimen cannot be determined. The test area will react with interfering substances known to react with Ehrlich's reagent, such as paminosalicylic acid. Drugs containing azo gantrisin (sulfamethoxazol) or high bilirubin may give a masking golden color. Preservative formaldehyde may cause false negatives. The test is not reliable method for the detection of porphobilinogen.
Glucose: Ascorbic acid (>40 mg/dL) may cause false negative results at low levels (100 mg/dL) of glucose. Ketones reduce the sensitivity of the test. Moderately high ketone levels (≥40 mg/dL) may cause false negatives for specimens containing a small amount of glucose (100 mg/dL). Chlorine Bleach (≥1%), low SG (≤1.000) and formaldehyde (≥150 mg/dL) may cause false positive results.
Bilirubin: Metabolites of drugs, such as selenium(≥220 mg/dL) or phenazopyridine(≥37 mg/dL) may cause false positives. p-Amino salicylic acid(≥1500 mg/dL) can produce a yellow-orange to red color response, which may lead to false positive bilirubin readings. Ascorbic acid (≥40 mg/dL) may cause false negatives.
Ketones: Low level false positive reactions may be seen in highly concentrated urine specimens (SG>1.004) or in specimens containing large amounts of levodopa drug metabolites such as captopril. The uroprotective drug mesna (sodium 2-mercaptoethane sulfonate) and other free-sulfhydryl compounds produce false-positive results in ketone methods that are based on the Legal reaction (alkaline sodium nitroprusside).
pH: If excessive urine remains on the strip because of improper test procedure, it is possible that the acidic buffer in the protein pad comes out and affects the neighboring pH pad, decreasing the measured pH. This phenomenon is called "run-over effect."
Blood: Elevated specific gravity (≥1.040) or protein in urine (≥1000 mg/dL) may reduce the sensitivity of the blood test pad leading to lower results. Microbial peroxidase associated with urinary tract infections may cause false positive results. Ascorbic acid concentrations (>30 mg/dl) may cause false negatives at trace levels of blood. Substances that cause abnormal urine color, such as drugs containing azo dyes, nitrofurantoin and riboflavin may cause false positive result. Strong oxidizing cleaning agents such as chlorine bleach cause false positive results.
Specific Gravity (SG): Alkaline urine (pH≥8) may cause false positive results.
Protein: False positive results may be found in strongly basic urine (pH>9). Protein testing should not be performed using turbid urine specimens. Metabolites of drugs such as acetaminophen may cause false positives. Hemoglobin may also cause false positives.
15
Pigments such as bilirubin and azo-containing compounds cause false positive results.
Nitrite: Ascorbic acid (≥40mg/dL) may cause false negative results with urine containing low levels of nitrite (