(146 days)
Not Found
No
The device is a quantitative in vitro diagnostic assay based on a chemical reaction, not AI/ML. The summary explicitly states "Mentions AI, DNN, or ML: Not Found".
No
This device is an in vitro diagnostic (IVD) assay used to quantitatively determine magnesium levels in body fluids. It is used for diagnosis and monitoring, not for direct treatment or therapy.
Yes
Explanation: The "Intended Use / Indications for Use" section explicitly states that the assay is "for in vitro diagnostic use in the quantitative determination of magnesium in human serum, plasma (lithium heparin), and urine" and that "Magnesium measurements are used in the diagnosis and treatment of hypomagnesemia... and hypermagnesemia". This directly indicates its role in diagnosis.
No
The device is an in vitro diagnostic assay, which is a chemical reagent kit used with a specific analyzer hardware (Atellica CH Analyzer) to measure magnesium levels in body fluids. It is not a software-only device.
Yes, this device is an IVD (In Vitro Diagnostic).
The "Intended Use / Indications for Use" section explicitly states: "The Atellica™ CH Magnesium (Mg) assay is for in vitro diagnostic use in the quantitative determination of magnesium in human serum, plasma (lithium heparin), and urine using the Atellica™ CH Analyzer."
This statement clearly identifies the device as being used outside of the body (in vitro) for diagnostic purposes.
N/A
Intended Use / Indications for Use
The Atellica™ CH Magnesium (Mg) assay is for in vitro diagnostic use in the quantitative determination of magnesium in human serum, plasma (lithium heparin), and urine using the Atellica™ CH Analyzer. Magnesium measurements are used in the diagnosis and treatment of hypomagnesemia (abnormally low levels of magnesium) and hypermagnesemia (abnormally high levels of magnesium).
Product codes (comma separated list FDA assigned to the subject device)
JGJ
Device Description
The Atellica CH Mg assay is based on the modified xylidyl blue reaction, which was first described by C.K. Mann and J.H. Yoe. 1-2 The reagent was modified to eliminate the use of organic solvents. Magnesium ions react with xylidyl blue in an alkaline medium to form a water-soluble purple-red complex. The increase in absorbance of xylidyl blue at 505/694 nm is proportional to the concentration of magnesium in the sample. Calcium is excluded from the reaction by complexing with EGTA.
Reaction Equation: Xylidyl Blue + Mg2+ OH- Xylidyl Blue (Mg2+) Complex
Serum, lithium heparin plasma and urine specimens may be used. The reagent is stored unopened at 2 - 8 °C and is stable for use on system for 14 days. Calibration is performed every 60 days for a reagent lot or every 3 days for an individual pack.
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
Not Found
Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
Assay performance comparison results for the Atellica CH Magnesium (Mg) were obtained by processing the appropriate body fluids. Summary statistics for each are provided. These data demonstrate substantial equivalency of the Atellica CH Magnesium (Mg) compared to the predicate device. The following data represent typical assay performance.
DETECTION LIMIT
Study Type: Limit of Blank (LoB) and Limit of Detection (LoD) evaluation in accordance with CLSI EP17-A2.
Sample Size: LoB: 4 samples with no analyte were tested (N=5) for 3 days, one run per day, 3 reagent lots. LoD: 4 low analyte samples were tested (N=5) for 3 days, one run per day, 3 reagent lots.
Key Results: LoB = 0.00 mg/dL. LoD = 0.02 mg/dL serum, 0.04 mg/dL urine.
LOQ (Limit of Quantitation)
Study Type: LoQ determination as described in CLSI Document EP17-A2.
Sample Size: For both serum/plasma and urine fluids, 4 low samples were processed on three reagent lots for three days, on one instrument for a total of 60 measurements per lot.
Key Results: Serum LoQ estimate is 0.46 mg/dL (0.19 mmol/L) with maximum allowable imprecision of 5% CV and maximum allowable bias of 15%. Urine LoQ estimates is 0.57 mg/dL (0.23 mmol/L) with maximum allowable imprecision of 5% CV and maximum allowable bias of 15%.
LINEARITY STUDY
Study Type: Linearity evaluation in accordance with CLSI Evaluation of the Linearity of Quantitative Measurement Procedure (EP06-A).
Sample Size: 10 samples for serum and 10 samples for urine, each with four replicates.
Key Results: Linearity of the Atellica CH Magnesium (Mg) was demonstrated with both serum and urine specimens to encompass the measuring intervals of 0.50 to 5.00 mg/dL for serum and plasma specimens and 1.00 to 14.00 mg/dL for urine specimens.
PRECISION STUDIES
Study Type: Precision testing in accordance with CLSI EP05-A3.
Sample Size: n = 2 replicates, two times a day for at least 20 days for a total of 80 replicates with controls, serum and plasma pools on one instrument.
Key Results:
Serum: Mean 0.78 mg/dL (CV 3.0% Rep., 3.9% Within-Lab); Mean 4.22 mg/dL (CV 0.6% Rep., 1.1% Within-Lab).
Plasma: Mean 1.51 mg/dL (CV 2.3% Rep., 3.4% Within-Lab).
Serum QC: Mean 2.53 mg/dL (CV 1.7% Rep., 2.0% Within-Lab).
Urine QC1: Mean 4.61 mg/dL (CV 0.8% Rep., 2.1% Within-Lab).
Urine QC2: Mean 11.19 mg/dL (CV 1.0% Rep., 1.3% Within-Lab).
INTERFERENCES
Study Type: Interference testing in accordance with CLSI EP7-A2.
Key Results: No interference was detected at specified concentrations for various substances in serum and urine (e.g., Hemoglobin 500 mg/dL, Bilirubin 30 mg/dL, Lipemia 500 mg/dL for serum; Hemoglobin 150 mg/dL, Ascorbate 50 mg/dL for urine).
METHOD COMPARISON
Study Type: Split sample method comparison following EP09-A3.
Sample Size: Serum N=108, Urine N=100.
Comparison Assay: Dimension Magnesium Flex Reagent Cartridge.
Key Results:
Serum: r = 0.996, y = 0.94x + 0.09 mg/dL. Sample Range 0.48-5.16 mg/dL.
Urine: r = 0.998, y = 0.96x - 0.06 mg/dL. Sample Range 1.10-13.22 mg/dL.
MATRIX EQUIVALENCY
Study Type: Additional method comparison study for lithium heparin plasma samples.
Sample Size: N=109.
Comparison Assay: Dimension Magnesium Flex Reagent Cartridge.
Key Results: Lithium heparin plasma: r = 0.998, y = 0.97x + 0.09 mg/dL. Sample Range 0.50-5.05 mg/dL.
EXTENDED MEASURING INTERVAL
Study Type: Evaluation of extended ranges by 2-fold manual dilutions.
Sample Size: 5 serum pools and 5 urine pools, with N=5 replicates processed for undiluted and diluted pools.
Key Results: Serum/plasma extended measuring interval is up to 10 mg/dL. Urine extended measuring interval up to 28 mg/dL.
STANDARDIZATION
Study Type: Traceability to Atomic Absorption reference method and testing with NIST SRM 929.
Sample Size: N=5 replicates with 3 reagent lots of Atellica CH Magnesium (Mg).
Key Results: All results recover within ± 5.0% of the expected value.
Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)
Not Found
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.
Dimension Magnesium Flex Reagent Cartridge (K861700)
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
§ 862.1495 Magnesium test system.
(a)
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).(b)
Classification. Class I.
0
Image /page/0/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized image of an eagle with three human profiles incorporated into its design. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES • USA" is arranged in a circular pattern around the eagle symbol.
Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002
SIEMENS HEALTHCARE DIAGNOSTICS, INC. LAURA DUGGAN REGULATORY TECHNICAL SPECIALIST 500 GBC DRIVE, PO BOX 6101 MS 514 NEWARK DE 19711
Re: K162399
Trade/Device Name: Atellica Ch Magnesium (Mg) Regulation Number: 21 CFR 862.1495 Regulation Name: Magnesium Test System Regulatory Class: I, reserved Product Code: JGJ Dated: December 14, 2016 Received: December 15, 2016
Dear Dr. Duggan:
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 Parts 801 and 809); medical device reporting (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 Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
January 19, 2017
1
If you desire specific advice for your device on our labeling regulations (21 CFR Parts 801 and 809), please contact the Division of Industry and Consumer Education at its toll-free number (800) 638 2041 or (301) 796-7100 or at its Internet address
http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm. 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.
You may obtain other general information on your responsibilities under the Act from the Division of Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address
http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.
Sincerely yours.
Katherine Serrano -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) K162399
Device Name Atellica CH Magnesium (Mg)
Indications for Use (Describe)
The Atellica™ CH Magnesium (Mg) assay is for in vitro diagnostic use in the quantitative determination of magnesium in human serum, plasma (lithium heparin), and urine using the Atellica™ CH Analyzer. Magnesium measurements are used in the diagnosis and treatment of hypomagnesemia (abnormally low levels of magnesium) and hypermagnesemia (abnormally high levels of magnesium).
| 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 10.
This summary of 510(k) safety and effectiveness information is submitted in accordance with the requirements of SMDA 1990 and 21 CFR §807.92.
ASSIGNED 510(K) NUMBER
The assigned 510(k) number is K162399.
APPLICANT AND DATE
Laura J. Duggan, Ph. D., RAC Siemens Healthcare Diagnostics Inc. 500 GBC Drive, M/S 514 Newark, DE 19714-6101 Email: laura.j.duggan@siemens.com Phone: 302-631-7654 Fax: 302-631-6299
January 19, 2017
MANUFACTURER
Siemens Healthcare Diagnostics Inc. 511 Benedict Ave Tarrytown, NY 10591 Registration Number: 2432235
REGULATORY INFORMATION
Regulatory Submission for the Atellica™ CH Magnesium (Mg)
| Common Name: | Photometric Method, Magnesium |
|---|---|
| Proprietary Name: | Atellica CH Magnesium (Mg) |
| Classification Name: | Magnesium Test System |
| Regulation Number: | 21CFR862.1495 |
| Classification: | Class I |
| Product Code: | JGJ |
| Panel: | Clinical Chemistry |
| Predicate Device: | Dimension Magnesium Flex |
| Reagent Cartridge (K861700) |
4
DEVICE DESCRIPTION
ATELLICA CH MAGNESIUM (MG)
The Atellica CH Mg assay is based on the modified xylidyl blue reaction, which was first described by C.K. Mann and J.H. Yoe. 1-2 The reagent was modified to eliminate the use of organic solvents. Magnesium ions react with xylidyl blue in an alkaline medium to form a water-soluble purple-red complex. The increase in absorbance of xylidyl blue at 505/694 nm is proportional to the concentration of magnesium in the sample. Calcium is excluded from the reaction by complexing with EGTA.
Reaction Equation
Xylidyl Blue + Mg2+
OH-
Xylidyl Blue (Mg2+) Complex
Serum, lithium heparin plasma and urine specimens may be used. The reagent is stored unopened at 2 - 8 °C and is stable for use on system for 14 days. Calibration is performed every 60 days for a reagent lot or every 3 days for an individual pack.
INTENDED USE/INDICATIONS FOR USE
ATELLICA CH MAGNESIUM (MG)
The Atellica™ CH Magnesium (Mg) assay is for in vitro diagnostic use in the quantitative determination of magnesium in human serum, plasma (lithium heparin), and urine using the Atellica™ CH Analyzer. Magnesium measurements are used in the diagnosis and treatment of hypomagnesemia (abnormally low levels of magnesium) and hypermagnesemia (abnormally high levels of magnesium).
COMPARISON OF TECHNOLOGICAL CHARACTERISTICS
Below is a features comparison for the Atellica CH Magnesium (Mg) assay and the predicate device:
5
| Feature | Predicate Device:
Dimension Magnesium Flex
Reagent Cartridge (K861700) | New Device:
Atellica CH Magnesium (Mg) |
|----------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Intended Use : | The MG method used on the
Dimension® clinical
chemistry system is an in
vitro diagnostic test intended
for the quantitative
determination of magnesium
in human serum,
heparinized plasma and
urine. | The Atellica™ CH
Magnesium (Mg) assay is for
in vitro diagnostic use in the
quantitative determination of
magnesium in human serum,
plasma (lithium heparin), and
urine using the Atellica™ CH
Analyzer. |
| Indications for Use: | | Magnesium measurements
are used in the diagnosis and
treatment of
hypomagnesemia
(abnormally low levels of
magnesium) and
hypermagnesemia
(abnormally high levels of
magnesium). |
| Device Technology: | Methylthymol blue (MTB)
complexometric procedure | Xylidyl blue reaction |
| Sample Type: | Serum, plasma and urine | Serum, Lithium Heparin
plasma, and urine |
| Expected Values: | Serum/Plasma
1.8 - 2.4 mg/dL
Urine
24 – 255 mg/24hr | Serum/plasma
1.60 to 2.60 mg/dL
Urine :
Same |
| Standardization: | NIST SRM 929 | Same |
6
| Calibration
| Frequency: | 90 days | 60 days |
|---|---|---|
| Analytical Measuring | ||
| Interval: | Serum/Plasma: | |
| 0.0 - 20.0 mg/dL | ||
| Urine: | ||
| 0.0 - 20.0 mg/dL | Serum and plasma: | |
| 0.50 to 5.00 mg/dL | ||
| Urine: 1.00 to 14.00 mg/dL | ||
| Interferences: | Bilirubin (Unconjugated) - | |
| 40 mg/dL | ||
| Lipemia (Intralipid®) - 1000 | ||
| mg/dL | ||
| Hemoglobin – 200 mg/dL | Bilirubin (Unconjugated) - 30 | |
| mg/dL | ||
| Bilirubin (Conjugated) - 30 | ||
| mg/dL | ||
| Lipemia (Intralipid®) - 500 | ||
| mg/dL | ||
| Hemoglobin - 500 mg/dL |
SUMMARY OF PERFORMANCE TESTING
Assay performance comparison results for the Atellica CH Magnesium (Mg) were obtained by processing the appropriate body fluids. Summary statistics for each are provided. These data demonstrate substantial equivalency of the Atellica CH Magnesium (Mg) compared to the predicate device. The following data represent typical assay performance.
DETECTION LIMIT
The Limit of Blank (LoB) and Limit of Detection (LoD) were evaluated in accordance with CLSI EP17-A2 Evaluation of Detection Capability for Clinical Laboratory Measurement Procedures; Approved Guideline.
Assessment of LoB was the 95th percentile of all values (sorted from lowest to highest), using non-parametric approach.
LoB Rank Position = 0.5 +0.95*B, where B=total reps=60; Rank = 57.5
| Atellica CH Magnesium (Mg) - Detection Capability | ||
|---|---|---|
| Limit | Protocol | Result |
7
| LoB | 4 samples with no analyte
were tested (N=5) for 3
days, one run per day, 3
reagent lots | 0.00 mg/dL |
|-----|--------------------------------------------------------------------------------------------------|--------------------------------------|
| LoD | 4 low analyte samples
were tested (N=5) for 3
days, one run per day, 3
reagent lots | 0.02 mg/dL serum
0.04 mg/dL urine |
LOQ
The Limit of Quantitation (LoQ) for serum was determined as described in CLSI Document EP17-A2. The mean, SD, %CV and bias relative to the reference values were calculated for each sample per reagent lot. The lowest sample concentration that met the maximum allowable imprecision and maximum allowable bias acceptance criteria was taken as the LoQ estimate for each reagent lot.
For both serum/plasma and urine fluids, 4 low samples were processed on three reagent lots for three days, on one instrument for a total of 60 measurements per lot. For serum LoQ estimate is 0.46 mg/dL (0.19 mmol/L) with maximum allowable imprecision of 5% CV and maximum allowable bias of 15%. For Urine LoQ estimates is 0.57 mg/dL (0.23 mmol/L) with maximum allowable imprecision of 5% CV and maximum allowable bias of 15%. For serum, the measured LoQ was 0.46 mg/dL in support of the low end of the measuring interval of 0.50 mg/dL for serum and plasma samples. For urine, the measured LoQ was 0.57 mg/dL in support of the low end of the measuring interval of 1.00 mg/dL for urine samples.
LINEARITY STUDY
Linearity was evaluated with 10 samples which spanned the assay measuring interval for serum specimens and 10 samples which spanned the assay measuring interval for urine specimens. Each was prepared by mixing high and low concentration samples across the measurement interval as described in CLSI Evaluation of the Linearity of Quantitative Measurement Procedure (EP06-A). The high sample was prepared by spiking native serum or urine pools with magnesium acetate. Low pools were created by diluting serum and urine samples with saline solution. Four replicates were measured for each sample. The mean of these replicates was used for the calculations.
The assay was considered linear across the measuring interval if the p values of nonlinear terms in the quadratic and cubic fit equations are nonsignificant (p ≤ 0.05). If
8
the p-value is > 0.05, then the allowable bias is ≤ 5% or 0.10 mg/dL, whichever is greater. Linearity of the Atellica CH Magnesium (Mg) was demonstrated with both serum and urine specimens to encompass the measuring intervals of 0.50 to 5.00 mg/dL for serum and plasma specimens and 1.00 to 14.00 mg/dL for urine specimens.
PRECISION STUDIES
Precision testing was performed in accordance with CLSI EP05-A3 Evaluation of Precision Performance of Quantitative Measurement Methods: Approved Guideline -Third Edition. Precision was tested n = 2 replicates, two times a day for at least 20 days for a total of 80 replicates with controls, serum and plasma pools on one instrument. Analysis of variance (ANOVA) was used to evaluate the data consistent with the recommendations of EP05-A3. The data are summarized in the following table.
| Repeatability | Within-Lab Precision | |||||
|---|---|---|---|---|---|---|
| Sample Type | n | Mean | ||||
| mg/dL (mmol/L) | SDa | |||||
| mg/dL (mmol/L) | CVb | |||||
| (%) | SDa | |||||
| mg/dL (mmol/L) | CVb | |||||
| (%) | ||||||
| Serum | 80 | 0.78 (0.32) | 0.023 (0.009) | 3.0 | 0.031 (0.013) | 3.9 |
| Plasma | 80 | 1.51 (0.62) | 0.034 (0.014) | 2.3 | 0.051 (0.021) | 3.4 |
| Serum QC | 80 | 2.53 (1.04) | 0.044 (0.018) | 1.7 | 0.050 (0.021) | 2.0 |
| Serum | 80 | 4.22 (1.74) | 0.024 (0.010) | 0.6 | 0.047 (0.019) | 1.1 |
| Urine QC1 | 80 | 4.61 (1.89) | 0.037 (0.015) | 0.8 | 0.097 (0.040) | 2.1 |
| Urine QC2 | 80 | 11.19 (4.60) | 0.108 (0.044) | 1.0 | 0.141 (0.058) | 1.3 |
ª SD = standard deviation
b CV = coefficient of variation
INTERFERENCES
CLSI EP7-A2 was followed for the interference testing. The interference study was conducted using a "paired difference worst case scenario" approach where these compounds were spiked into fresh sample pools containing either low or high levels of measurand in serum and urine pools.
9
Bias is the difference in the results between the control sample (without the interferent) and the test sample (contains the interferent) expressed in percent. Bias exceeding 10% is considered interference. Dilution studies were conducted to determine the level at which the spiked substance no longer displayed significant interference. Dilution studies were conducted at two analyte concentrations, if both sample pools show significant interference. This study was conducted as needed for both serum pools.
| Approximate Concentration (within 15%) of Analytes in Test Pools | |||
|---|---|---|---|
| Analyte | Matrix | Low | High |
| Magnesium | Serum | 1.60 mg/dL | 2.60 mg/dL |
| Magnesium | Urine | 2.00 mg/dL | 6.00 mg/dL |
No interference was detected at the following analyte concentrations.
Interference Testing for Serum
| Substance | Substance Test Concentration
Common Unit |
|----------------------------|---------------------------------------------|
| Hemoglobin | 500 mg/dL |
| Bilirubin, conjugated | 30 mg/dL |
| Bilirubin,
unconjugated | 30 mg/dL |
| Lipemia (Intralipid®) | 500 mg/dL |
| EDTA | 12.5 mg/dL |
| Copper | 0.50 mg/dL |
| Calcium | 20 mg/dL |
| Iron | 0.50 mg/dL |
| Zinc | 0.25 mg/dL |
| Acetaminophen | 200 mg/dL |
| Ibuprofen | 500 mg/dL |
Interference Testing for Urine
| Substance | Substance Test Concentration
Common Unit |
|----------------------|---------------------------------------------|
| 6N HCl | 0.01% HCl |
| Ascorbate | 50 mg/dL |
| Hemoglobin | 150 mg/dL |
| Calcium | 20 mg/dL |
| Conjugated Bilirubin | 30 mg/dL |
| Copper | 0.50 mg/dL |
| Iron | 0.50 mg/dL |
| Zinc | 0.25 mg/dL |
METHOD COMPARISON
10
The predicate device selected for the method comparison study was the Dimension Magnesium Flex Reagent Cartridge. Remnant de-identified samples were tested. No patient history information was obtained on these samples. Inclusion/exclusion data criteria are not applicable. The study included native and diluted samples to properly span the assay intervals.
These studies were conducted internally by Siemens Healthcare Diagnostic Inc. R&D organization personnel. The personnel conducting the study were laboratory technicians with training similar to personnel who would conduct the tests in a hospital laboratory setting. They were trained on the operation of both the device and the predicate device. A split sample method comparison, following EP09-A3, demonstrated good agreement between the Atellica CH Magnesium (Mg) and the predicate Dimension Magnesium Flex Reagent Cartridge (Mg) assay with patient samples.
The results across the full assay intervals were analyzed using Deming regression. One replicate of each sample was tested and used in the analysis.
| Specimen
Type | Comparison
Assay (x) | N | r | Regression
Equation | Sample Range (on
the Dimension RxL) |
|------------------|-------------------------|-----|-------|----------------------------------------------|---------------------------------------------|
| Serum | Dimension RxL
Mg | 108 | 0.996 | $y = 0.94x + 0.09$
mg/dL (0.04
mmol/L) | 0.48-5.16 mg/dL
(0.20 - 2.12
mmol/L) |
| Urine | Dimension RxL
Mg | 100 | 0.998 | $y = 0.96x - 0.06$
mg/dL (0.02
mmol/L) | 1.10-13.22 mg/dL
(0.45 - 5.43
mmol/L) |
MATRIX EQUIVALENCY
Due to the difficulty with obtaining matched serum and plasma magnesium samples across the measuring interval, an additional method comparison study was conducted with lithium heparin plasma samples on Atellica CH Magnesium (Mg) and Dimension Magnesium Flex Reagent Cartridge. Some samples were diluted to obtain samples spanning the assay measuring interval. The table below summarizes the Deming linear regression statistics. One replicate of each sample was tested and used in the analysis.
| Specimen
Type | Comparison
Assay (x) | N | r | Regression
Equation | Sample Range (on
the Dimension
RxL) |
|------------------------------|-------------------------|-----|-------|--------------------------------------------|--------------------------------------------|
| Lithium
heparin
plasma | Dimension RxL
Mg | 109 | 0.998 | y = 0.97x + 0.09
mg/dL (0.04
mmol/L) | 0.50-5.05 mg/dL
(0.21 - 2.08
mmol/L) |
EXPECTED VALUES
11
Reference intervals for healthy adults were verified on the Atellica CH Analyzer in accordance with CLSI Document EP28-A3c. As with all in vitro diagnostic assays, each laboratory should determine its own reference interval for the diagnostic evaluation of patient results. Consider these values as guidance only.
| Group | Specimen type | Reference Interval
common unit (SI unit) |
|--------|---------------|------------------------------------------------------|
| Adults | Serum/plasma1 | 1.60 to 2.60 mg/dL (0.66 to 1.07 mmol/L) |
| Adults | Urine2 | 24 to 255 mg/24 hour (0.99 to 10.45
mmol/24 hour) |
Wu AHB. Tietz Clinical Guide to Laboratory Tests. 4™ ed. Philadelphia, PA: WB Saunders Co: 2006:706.
- Pesce, A.J. and Kaplan, L.A., Methods in Clinical Chemistry, C.V. Mosby Co., St. Louis, 1987. 1.
EXTENDED MEASURING INTERVAL
The Mq assay parameters support both serum/plasma and urine extended ranges 2x the upper measuring intervals. Two-fold manual dilutions of 5 serum pools and 5 urine pools were made with CH Diluent, and both the undiluted and diluted pools were processed with N=5 replicates. The serum/plasma extended measuring interval is up to 10 mg/dL. The urine extended measuring interval up to 28 mg/dL.
STANDARDIZATION
Magnesium values are traceable to Atomic Absorption reference method which is calibrated with NIST SRM 929 reference material. SRM909 reference material from the National Institute of Standards and Technology (NIST) was processed with N=5 replicates with 3 reagent lots of Atellica CH Maqnesium (Mg) and the mean results were compared to the target value. All results recover within ± 5.0% of the expected value.
CONCLUSION
The Atellica CH Magnesium (Mg) is substantially equivalent to the Dimension Magnesium Flex Reagent Cartridge in principle and performance based on the similarity of device designs and function demonstrated through method comparison and other performance attributes.