CELL-CHEX

K101335 · Streck · GLQ · Aug 23, 2010 · Hematology

Device Facts

• Record ID: K101335
• Device Name: CELL-CHEX
• Applicant: Streck
• Product Code: GLQ · Hematology
• Decision Date: Aug 23, 2010
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 864.8625
• Device Class: Class 2

Indications for Use

Cell-Chex™ is an assayed control intended for monitoring total cell counts performed manually using a hemocytometer to validate quantitation of red and white blood cells in patient cerebrospinal fluid and body fluid samples including pleural, pericardial, peritoneal and synovial fluid. Level 1 contains monosodium urate crystals which can be used to monitor the presence of crystals in synovial fluid. Cell-Chex™ is also intended for monitoring white blood cell differentiation (Mononuclear and Polymorphonuclear; Neutrophils, Eosinophils, Basophils, Lymphocytes, and Monocytes) in body fluid samples performed using Cytospin® smears.

Device Story

Cell-Chex™ is a stabilized suspension of human RBCs, WBCs, and monosodium urate crystals (Level 1 only) in preservative medium. Used as an in-vitro diagnostic quality control for body fluid analysis. Laboratory personnel perform manual total cell counts via hemocytometer and WBC differential counts via Cytospin® smears with routine hematology staining. Crystal analysis is performed via light or polarized light microscopy. The control validates the accuracy and precision of these manual laboratory procedures. By providing known values for cell counts and crystal presence, the device allows clinicians to verify the performance of their diagnostic testing protocols, ensuring reliable results for patient body fluid samples.

Clinical Evidence

No clinical data. Bench testing only. Precision and reproducibility were evaluated across three lots and eight external sites using hemocytometer and Cytospin® platforms. Results confirmed performance within ±3SD for WBC differential parameters and ±2SD for RBC/WBC parameters. Stability testing (open-vial 30 days, closed-vial 60 days) confirmed performance consistency.

Technological Characteristics

Stabilized suspension of human RBCs, WBCs, and monosodium urate crystals in preservative medium. Two levels (Level 1: low cell count + crystals; Level 2: high cell count). Packaged in 2 mL glass vials. Analyzed via manual hemocytometer, light/polarized light microscopy, and Cytospin® smears with hematology staining. Complies with CLSI EP5-A2 guidelines for precision evaluation.

Indications for Use

Indicated for use as an assayed quality control for monitoring manual hemocytometer total cell counts (RBC, WBC) and Cytospin® smear WBC differential counts in cerebrospinal and body fluids (pleural, pericardial, peritoneal, synovial). Level 1 is indicated for monitoring monosodium urate crystals in synovial fluid. For prescription use only.

Regulatory Classification

Identification

A hematology quality control mixture is a device used to ascertain the accuracy and precision of manual, semiautomated, and automated determinations of cell parameters such as white cell count (WBC), red cell count (RBC), platelet count (PLT), hemoglobin, hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC).

Special Controls

*Classification.* Class II (special controls). Except when intended for use in blood components, the device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 864.9.

Predicate Devices

• Cell-Chex™ (k000076)

Submission Summary (Full Text)

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510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION
DECISION SUMMARY

A. 510(k) Number:
k101335

B. Purpose for Submission:
Clearance of a new device with a 5-part differential for WBC and ability to detect crystals in synovial fluid. This device will replace the currently cleared Cell-Chex™ and will have the same trade name.

C. Measurand:
Assayed control for Red Blood Cells (RBC), White Blood Cells (WBC), Neutrophils (NEUT) %, Lymphocytes (LYM)%, Monocytes (MONO) %, Eosinophils (EOS) %, and Basophils (BASO) %, Mononuclear %, Polymorphonuclear %, Monosodium Urate Crystals.

D. Type of Test:
Quantitative and Qualitative

E. Applicant:
Streck Inc.

F. Proprietary and Established Names:
Cell-Chex™

G. Regulatory Information:
1. Regulation section:
21 CFR 864.8625, Hematology quality control mixture
2. Classification:
Class II
3. Product code:
GLQ, Mixture, Control, White Cell and Red Cell Indices
4. Panel:
81 (Hematology)

H. Intended Use:
1. Intended use(s):
Cell-Chex™ is an assayed control intended for monitoring total cell counts performed manually using a hemocytometer to validate quantitation of red and white blood cells in patient cerebrospinal fluid and body fluid samples including pleural, pericardial, peritoneal and synovial fluid. Level 1 contains monosodium urate crystals which can be used to monitor the presence of crystals in synovial fluid. Cell-Chex™ is also intended for monitoring white blood cell differentiation (Mononuclear and Polymorphonuclear; Neutrophils, Eosinophils, Basophils, Lymphocytes, and Monocytes) in body fluid samples performed using Cytospin® smears.
2. Indication(s) for use:
Same as intended use(s)
3. Special conditions for use statement(s):
For prescription use only
4. Special instrument requirements:
Not applicable

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I. Device Description:

Cell-Chex™ is a stabilized suspension of human red blood cells (RBC), human white blood cells (WBC) and monosodium urate crystals (Level 1 only) in a preservative medium. In addition, Level 1 contains a low cell count and Level 2 contains a high cell count.

J. Substantial Equivalence Information:

1. Predicate device name(s):
Cell-Chex™

2. Predicate K number(s):
k000076

3. Comparison with predicate:
| Similarities | | |
| --- | --- | --- |
| Item | Cell-Chex™ | Cell-Chex™ (predicate) |
| Intended Use | An assayed control intended for monitoring total cell counts performed manually using a hemocytometer to validate quantitation of red and white blood cells in patient cerebrospinal fluid and body fluid samples including pleural, pericardial, peritoneal and synovial fluid. | Same |
| Final Product Form | There are two different levels. The product is packaged in glass vials containing 2 mL. The vials are packaged in a six (6) or twelve (12) welled vacuum formed “clam shell” container with instructions for use and assay sheet. | Same |
| Open vial stability | 30 days when stored at 2-10°C | Same |
| Differences | | |
| --- | --- | --- |
| Item | Cell-Chex™ | Cell-Chex™ (predicate) |
| Analytes | Detects crystals in synovial fluid
Provides 5-part differential for WBC (Neutrophils, Eosinophils, Basophils, Lymphocytes, and Monocytes) in body fluid samples performed using Cytospin® smears | Does not detect crystals in synovial fluid
Does not provide 5-part differential for WBC in body fluids |
| Reagents | Level 1 contains monosodium urate crystals | No monosodium urate crystals |
| Closed vial stability | 60 days when stored at 2-10°C | 6 months when stored at 2-10°C |

K. Standard/Guidance Document Referenced (if applicable):

CLSI, Evaluation of Precision of Quantitative Measurement Methods; Approved Guidelines-Second Edition (EP5-A2).

L. Test Principle:

Cell-Chex™ is an in-vitro diagnostic product that is used for quality control

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procedures associated with body fluid counting protocols. Total cell counts are performed with a hemocytometer. Crystal analysis can be performed using light or polarized light microscopy. Differential cell counts of body fluids are performed using Cytospin® smears stained by means of routine hematology staining techniques.

## M. Performance Characteristics:

### 1. Analytical performance:

#### a. Precision/Reproducibility:

Run-to-run reproducibility: Streck produced data from 10 consecutive runs on three lots of each control level on both the hemacytometer and Cytospin®. The results fell within parameter specific assay value assignment ranges and are reflective of ±3SD for the WBC differential parameters and ±2SD for the red and white blood cell parameters. Level 1 results were positive for crystals. Level 2 results were negative for crystals.

Precision performance: Data was collected internally and at external sites. Streck selected eight external sites to run a single lot of Cell-Chex control in accordance with the product's instructions for use (IFU) using the hemacytometer and Cytospin®. Cell-Chex control materials were stored by the external sites and handled in accordance with the IFU. The controls were run between 14-17 times over the course of several weeks. The results fell within parameter specific assay value assignment ranges and are reflective of ±3SD for the WBC differential parameters and ±2SD for the red and white blood cell parameters. Level 1 results were positive for crystals. Level 2 results were negative for crystals.

#### b. Linearity/assay reportable range:

Not applicable

#### c. Traceability, Stability, Expected values (controls, calibrators, or methods):

Value assignment: Specific to each lot and level of control, a total of five vials were analyzed in duplicate. A cumulative mean, standard deviation and %CV were calculated for all measurands reported using Cell-Chex™ with the hemacytometer and Cytospin® platforms. Crystals were identified as "positive" if observed microscopically. The parameter specific assay value assignment ranges are reflective of ±3SD for the WBC differential parameters and ±2 SD for the RBC and WBC parameters.

Open vial stability: At each testing interval the vials of control were analyzed one time with the hemacytometer and Cytospin®. On non-testing days, all vials of control were removed from 2-10°C storage, equilibrated to room temperature and mixed in accordance with the IFU. Three separate lots were analyzed to verify performance throughout the proposed 30 day open vial dating. The results fell within parameter specific assay value assignment ranges and are reflective of ±3SD for the WBC differential parameters and ±2SD for the red and white blood cell parameters. Level 1 results were positive for crystals. Level 2 results were negative for crystals.

Closed vial stability: The control vials were analyzed 10-15 times over the

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course of 60 days. Control vials were then analyzed once using both the hemacytometer and Cytospin™. Three separate lots were set up to verify performance throughout the 60 day expiration dating. The results fell within parameter specific assay value assignment ranges and are reflective of ±3SD for the WBC differential parameters and ±2SD for the red and white blood cell parameters. Level 1 results were positive for crystals. Level 2 results were negative for crystals.

d. Detection limit:
Not applicable

e. Analytical specificity:
Not applicable

f. Assay cut-off:
Not applicable

2. Comparison studies:
a. Method comparison with predicate device:
Not applicable
b. Matrix comparison:
Not applicable

3. Clinical studies:
a. Clinical Sensitivity:
Not applicable
b. Clinical specificity
Not applicable
c. Other clinical supportive data (when a. and b. are not applicable):
Not applicable

4. Clinical cut-off: Not applicable
5. Expected values/Reference range: Not applicable

N. Proposed Labeling:
The labeling is sufficient and it satisfies the requirements of 21 CFR Part 809.10.

O. Conclusion:
The submitted information in this premarket notification is complete and supports a substantial equivalence decision.