K223179 · Alere San Diego, Inc. · CGA · Sep 20, 2023 · Clinical Chemistry
Device Facts
Record ID
K223179
Device Name
Cholestech LDX ™ System
Applicant
Alere San Diego, Inc.
Product Code
CGA · Clinical Chemistry
Decision Date
Sep 20, 2023
Decision
SESE
Submission Type
Dual Track
Regulation
21 CFR 862.1345
Device Class
Class 2
Attributes
Pediatric
Indications for Use
The Cholestech LDX™ System is a small, portable analyzer and test cassette system. The System is for in vitro diagnostic use only and should not be used for testing in children under the age of 2 years. The Cholestech LDX™ System is comprised of the Cholestech LDX Analyzer and the following cassettes: The Lipid Profile•GLU cassette is for the quantitative determination of total cholesterol, HDL (high-density lipoprotein) cholesterol, triglycerides and glucose in whole blood. The TC/HDL (total cholesterol/HDL cholesterol) ratio and estimated values for LDL (low-density lipoprotein) and non-HDL cholesterol are also reported. The TC•HDL•GLU cassette is for the quantitative determination of total cholesterol, HDL (high-density lipoprotein) cholesterol, and glucose in whole blood. The TC•GLU cassette is for the quantitative determination of total cholesterol and glucose in whole blood. The Lipid Profile cassette is for the quantitative determination of total cholesterol, HDL (high-density lipoprotein) cholesterol, and triglycerides in whole blood. The TC/HDL (total cholesterol/HDL cholesterol) ratio and estimated values for LDL (low-density lipoprotein) and non-HDL cholesterol are also reported. The TC•HDL cassette is for the quantitative determination of total cholesterol and HDL (high-density lipoprotein) cholesterol in whole blood. The TC cassette is for the quantitative determination of total cholesterol in whole blood. Cholesterol measurements are used in the diagnosis and treatment of disorders involving excess cholesterol in the blood and lipid and lipoprotein metabolism disorders. HDL (lipoprotein) measurements are used in the diagnosis and treatment of lipid disorders (such as diabetes mellitus), atherosclerosis, and various liver and renal diseases. Triglyceride measurements are used in the diagnosis and treatment of patients with diabetes mellitus, nephrosis, liver obstruction, other diseases involving lipid metabolism, or various endocrine disorders. Glucose measurements are used in the diagnosis and treatment of carbohydrate metabolism disorders including diabetes mellitus, idiopathic hypoglycemia, and of pancreatic islet cell carcinoma.
Device Story
Portable analyzer and test cassette system; uses reflectance photometry to measure color changes on reagent pads; determines concentration of total cholesterol, HDL, triglycerides, and glucose in venous or capillary whole blood; calculates LDL, non-HDL, and TC/HDL ratio. Operated by professionals in clinical settings. Modification adds software-enforced limitations for hyperbilirubinemia and pediatric use (under 2 years); analyzer displays warning on screen, printed results, and EMR output. Benefits include rapid point-of-care lipid and glucose assessment for diagnosis/treatment of metabolic disorders.
Clinical Evidence
Bench testing only. Verification studies performed under design control to validate device modifications, including interference testing for conjugated and unconjugated bilirubin. Acceptance criteria met.
Technological Characteristics
Reflectance photometry; enzymatic assays; portable analyzer with LCD; whole blood sample input. Software-based warning system for specific patient populations. Sterilization/materials not specified. Complies with CLSI EP07-A3 for interference testing.
Indications for Use
Indicated for quantitative determination of total cholesterol, HDL cholesterol, triglycerides, and glucose in whole blood (fingerstick or venipuncture) for patients aged 2 years and older. Used for diagnosis/treatment of lipid, lipoprotein, and carbohydrate metabolism disorders, atherosclerosis, and liver/renal diseases. Contraindicated for children under 2 years of age.
Regulatory Classification
Identification
A glucose test system is a device intended to measure glucose quantitatively in blood and other body fluids. Glucose measurements are used in the diagnosis and treatment of carbohydrate metabolism disorders including diabetes mellitus, neonatal hypoglycemia, and idiopathic hypoglycemia, and of pancreatic islet cell carcinoma.
Special Controls
*Classification.* Class II (special controls). The device, when it is solely intended for use as a drink to test glucose tolerance, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9.
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FDA
U.S. FOOD & DRUG
ADMINISTRATION
# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY
ASSAY ONLY
## I Background Information:
A 510(k) Number
K223179
B Applicant
Alere San Diego, Inc.
C Proprietary and Established Names
Cholestech LDX™ System
D Regulatory Information
| Product Code(s) | Classification | Regulation Section | Panel |
| --- | --- | --- | --- |
| CGA | Class II | 21 CFR 862.1345 - Glucose Test System | CH - Clinical Chemistry |
| CHH | Class I | 21 CFR 862.1175 - Cholesterol (total) test system | CH - Clinical Chemistry |
| JGY | Class I | 21 CFR 862.1705 - Triglyceride test system | CH - Clinical Chemistry |
| JJE | Class I | 21 CFR 862.2160 - Discrete photometric chemistry analyzer for clinical use | CH - Clinical Chemistry |
| LBS | Class I | 21 CFR 862.1475 - Lipoprotein test system | CH - Clinical Chemistry |
Food and Drug Administration
10903 New Hampshire Avenue
Silver Spring, MD 20993-0002
www.fda.gov
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K223179 - Page 2 of 7
## II Submission/Device Overview:
### A Purpose for Submission:
Modification of a previously cleared device
### B Measurand:
- Total cholesterol (TC)
- High-density lipoprotein (HDL)
- Triglycerides (TRG)
- Glucose (GLU)
### C Type of Test:
Quantitative, enzymatic photometric
## III Intended Use/Indications for Use:
### A Intended Use(s):
See Indications for Use below.
### B Indication(s) for Use:
The Cholestech LDX™ System is a small, portable analyzer and test cassette system. The System is for in vitro diagnostic use only and should not be used for testing in children under the age of 2 years. The Cholestech LDX™ System is comprised of the Cholestech LDX Analyzer and the following cassettes:
The Lipid Profile•GLU cassette is for the quantitative determination of total cholesterol, HDL (high-density lipoprotein) cholesterol, triglycerides and glucose in whole blood. The TC/HDL (total cholesterol/HDL cholesterol) ratio and estimated values for LDL (low-density lipoprotein) and non-HDL cholesterol are also reported.
The TC•HDL•GLU cassette is for the quantitative determination of total cholesterol, HDL (high-density lipoprotein) cholesterol, and glucose in whole blood.
The TC•GLU cassette is for the quantitative determination of total cholesterol and glucose in whole blood.
The Lipid Profile cassette is for the quantitative determination of total cholesterol, HDL (high-density lipoprotein) cholesterol, and triglycerides in whole blood. The TC/HDL (total cholesterol/HDL cholesterol) ratio and estimated values for LDL (low-density lipoprotein) and non-HDL cholesterol are also reported.
The TC•HDL cassette is for the quantitative determination of total cholesterol and HDL (high-density lipoprotein) cholesterol in whole blood.
The TC cassette is for the quantitative determination of total cholesterol in whole blood.
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- Cholesterol measurements are used in the diagnosis and treatment of disorders involving excess cholesterol in the blood and lipid and lipoprotein metabolism disorders.
- HDL (lipoprotein) measurements are used in the diagnosis and treatment of lipid disorders (such as diabetes mellitus), atherosclerosis, and various liver and renal diseases.
- Triglyceride measurements are used in the diagnosis and treatment of patients with diabetes mellitus, nephrosis, liver obstruction, other diseases involving lipid metabolism, or various endocrine disorders.
- Glucose measurements are used in the diagnosis and treatment of carbohydrate metabolism disorders including diabetes mellitus, idiopathic hypoglycemia, and of pancreatic islet cell carcinoma.
## C Special Conditions for Use Statement(s):
Rx - For Prescription Use Only
Limitation – Cholestech LDX™ is not for use in children under the age of 2 years or patients with hyperbilirubinemia (Elevated bilirubin levels).
## D Special Instrument Requirements:
Cholestech LDX™ Analyzer.
## IV Device/System Characteristics:
### A Device Description:
The Cholestech LDX™ System is a small, portable analyzer and test cassette system. The system is for in vitro diagnostic use only. The Analyzer uses reflectance photometry (the amount of light reflected from a solid surface) to determine the amount of the analyte in blood. The analyzer measures color changes of the four reagent pads. The amount of color formed is converted by the analyzer to a concentration and the results are shown on the liquid crystal display (LCD) screen. The assays for use on the Analyzer include total cholesterol (TC), high-density lipoprotein cholesterol (HDL), triglycerides (TRG), glucose (GLU), and by calculation, low-density lipoprotein (LDL), non-HDL cholesterol, and total cholesterol/HDL cholesterol ratio.
The modification that is the subject of this submission addresses revised bilirubin interference claims for all analytes (see Section VII.A.3.) and includes a new limitation and a software upgrade to mitigate the modified risks. The revised limitations consist of the statement "Cholestech LDX™ is not for use in children under the age of 2 years or patients with hyperbilirubinemia (Elevated bilirubin levels)". The software upgrade incorporates the revised limitations, displaying it on the Cholestech LDX™ analyzer screen, printing it on all paper test results, and presenting it on all results sent to the electronic medical record.
K223179 - Page 3 of 7
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B Principle of Operation:
The Cholestech LDX™ System principle of operation has not changed since the review of K120615.
V Substantial Equivalence Information:
A Predicate Device Name(s):
Alere Cholestech LDX Analyzer, Alere Cholestech LDX Lipid Profile - GLU Cassette
B Predicate 510(k) Number(s):
K120615
C Comparison with Predicate(s):
| Device & Predicate Device(s): | K223179 | K120615 |
| --- | --- | --- |
| Device Trade Name | Cholestech LDX™ System (Modified) | Cholestech LDX Analyzer and Cholestech LDX Lipid Profile•GLU Cassette |
| General Device Characteristic Similarities | | |
| Intended Use/Indications For Use | For the quantitative determination of total cholesterol, HDL cholesterol, triglycerides, and glucose in whole blood. | Same |
| Sample Type | Venous and Capillary Whole Blood | Same |
| Type of Use | For professional in vitro diagnostic use only | Same |
| General Device Characteristic Differences | | |
| Limitations | To address revised interference claims from conjugated and unconjugated bilirubin, the modified device includes the following limitation “Cholestech LDX™ is not for use in children under the age of 2 years or patients | Does not include the limitation |
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K223179 - Page 5 of 7
| Device & Predicate Device(s): | K223179 | K120615 |
| --- | --- | --- |
| | with hyperbilirubinemia (Elevated bilirubin levels)". | |
## VI Standards/Guidance Documents Referenced:
CLSI – EP07-A3 – Interference Testing in Clinical Chemistry – 3rd edition
## VII Performance Characteristics (if/when applicable):
### A Analytical Performance:
1. **Precision/Reproducibility:**
This performance characteristic was established in the previous 510(k) submissions, reviewed under K901900, K912136, K914469, K922612, K932727, K914033, K905296 and K904082.
2. **Linearity:**
This performance characteristic was established in the previous 510(k) submissions, reviewed under K901900, K912136, K914469, K922612, K932727, K914033, K905296 and K904082.
3. **Analytical Specificity/Interference:**
Interference testing was performed based on guidance from CLSI EP07-A3 and a study evaluating two interferents*, conjugated and unconjugated bilirubin was conducted. For the study, target analytes at different concentrations; triglycerides (100 mg/dL and 250 mg/dL), HDL (30 mg/dL and 80 mg/dL), glucose (50-70 mg/dL, 110-130 mg/dL and 225-270 mg/dL), total cholesterol (150 mg/dL and 220 mg/dL) were created in pooled samples that were spiked with the interferents, conjugated and unconjugated bilirubin, at a range of concentrations. Samples were tested in replicates of sixteen (16) using three (3) Cholestech LDX™ Lipid Profile Glucose test cassettes, on sixteen (16) Cholestech LDX™ Analyzers. The following table list the concentration of each substance at which no significant interference was detected; defined by the sponsor as a difference of less than or equal to ±10% between the test sample and control:
| Analyte | Analyte Target Values | Highest concentration with no observed Unconjugated Bilirubin Interference (mg/dL) | Highest concentration with no observed Conjugated Bilirubin Interference (mg/dL) |
| --- | --- | --- | --- |
| Total Cholesterol | 150 mg/dL ± 10% | 7.5 | 10 |
| | 220 mg/dL ± 10% | 7.5 | 12.5 |
| Triglycerides | 100 mg/dL ± 10% | 5 | 3.75 |
| | 250 mg/dL ± 10% | 5 | 7.5 |
| | 30 mg/dL ± 10% | 2.5 | 2.5 |
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| Analyte | Analyte Target Values | Highest concentration with no observed Unconjugated Bilirubin Interference (mg/dL) | Highest concentration with no observed Conjugated Bilirubin Interference (mg/dL) |
| --- | --- | --- | --- |
| HDL | 80 mg/dL ± 10% | 5 | 12.5 |
| Glucose | 50-70 mg/dL | 10 | 12.5 |
| | 110-130 mg/dL | 20 | 15 |
| | 225-270 mg/dL | 27.1 | 35 |
Potential interference from conjugated and unconjugated bilirubin was also estimated for the calculated parameters.
Based on the data, the sponsor updated the interference claims in their labeling for the test system for conjugated and unconjugated bilirubin to indicate that concentrations up to 2.5 mg/dL do not interfere with the test system.
*Other aspects of this performance characteristic (including additional interferent testing) were established in the previous 510(k) submissions, reviewed under K901900, K912136, K914469, K922612, K932727, K914033, K905296, K904082 and K120615.
4. Assay Reportable Range:
This performance characteristic was established in the previous 510(k) submissions, reviewed under K901900, K912136, K914469, K922612, K932727, K914033, K905296 and K904082.
5. Traceability, Stability, Expected Values (Controls, Calibrators, or Methods):
This performance characteristic was established in the previous 510(k) submissions, reviewed under K901900, K912136, K914469, K922612, K932727, K914033, K905296 and K904082.
6. Detection Limit:
This performance characteristic was established in the previous 510(k) submissions, reviewed under K901900, K912136, K914469, K922612, K932727, K914033, K905296 and K904082.
7. Assay Cut-Off:
Not applicable.
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## B Comparison Studies:
1. **Method Comparison with Predicate Device:**
This performance characteristic was established in the previous 510(k) submissions, reviewed under K901900, K912136, K914469, K922612, K932727, K914033, K905296 and K904082.
2. **Matrix Comparison:**
This performance characteristic was established in the previous 510(k) submissions, reviewed under K901900, K912136, K914469, K922612, K932727, K914033, K905296 and K904082.
## C Clinical Studies:
1. **Clinical Sensitivity:**
Not applicable.
2. **Clinical Specificity:**
Not applicable.
3. **Other Clinical Supportive Data (When 1. and 2. Are Not Applicable):**
Not applicable.
## D Clinical Cut-Off:
Not applicable.
## E Expected Values/Reference Range:
The Cholestech LDX™ System’s expected values/reference range has not changed since the review of K120615.
## VIII Proposed Labeling:
The labeling supports the finding of substantial equivalence for this device.
## IX Conclusion:
The submitted information in this premarket notification is complete and supports a substantial equivalence decision.
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Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.