The COULTER® AC T diff 2m analyzer is a quantitative, automated hematology analyzer and leukocyte differential counter For In Vitro Diagnostic Use in clinical laboratories.

An automated differential cell counter is a device used to identify and classify one or more of the formed elements of blood.

Device Description

The COULTER® Ac·T diff 2™ Analyzer is a quantitative, automated hematology analyzer and leukocyte differential counter For In Vitro Diagnostic Use in clinical laboratories. COULTER® Ac.T diff 2™ Analyzer has the same technological characteristics and is substantially equivalent to the COULTER® COUNTER® S-PLUS IV and LYSE S PLUS D (also called COULTER COUNTER® Model S PLUS IV with Three Population Differential and Model S PLUS IV Diff), which was cleared by 510(k) K823355 on Dec. 28, 1982 and is a modified version of the COULTER® Ac-T diff ™ Analyzer which were cleared by 510(k) K973634 on October 29, 1997.

As with the predicate devices, the COULTER® Ac-T diff 2™ Analyzer utilizes the Coulter principle for the enumeration and sizing of blood cells, in combination with an automatic diluting and mixing device for sample processing and a single beam photometer for the measurement of hemoglobin. The same reagent system, composed of an isotonic diluent, lyitc reagent to lyse red blood cells for WBC and hemoglobin measurement and instrument cleaner, is used on Model S PLUS IV Diff and Ac-T diff Analyzers.

All the devices determine the following CBC parameters: WBC, LY #, LY%, MO #, MO %, GR #, GR %, RBC, Hgb, Hct, MCV, MCH, MCHC, Plt, RDW, MPV. Pct* and PDW* are also measured. *These parameters are not for diagnostic use but can be used as internal instrument checks on the platelet parameters.

Like the Ac T diff Analyzer, the Ac T diff 2 can analyze samples in either of two modes: whole blood and pre-dilute. Additionally, the Ac-T diff 2 can sample closed vial specimens by virtue of a rotary cap piercing functionality. The MODEL S PLUS IV Diff does not have a pre-dilute mode or a closed vial sampling mode.

AI/ML Overview

This document is primarily a 510(k) submission, which focuses on demonstrating substantial equivalence to a predicate device rather than presenting a detailed study proving the device meets specific acceptance criteria in the same way a de novo or PMA submission might.

Therefore, the requested information, particularly regarding acceptance criteria, a study proving the device meets the criteria, sample sizes for test sets and training sets, expert qualifications, and ground truth adjudication, is not explicitly provided in the given text.

The document describes the device, its intended use, and compares its technological characteristics to predicate devices. It states that the device "has the same technological characteristics" and is "substantially equivalent" to the predicate. This implies that the performance characteristics are expected to be similar, but it doesn't detail a specific acceptance criteria study for this new device.

However, based on the information provided, here's what can be extracted and inferred:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state "acceptance criteria" for the COULTER® Ac·T diff 2™ Analyzer. Instead, it outlines the parameters measured by the device and asserts its substantial equivalence to predicate devices, implying that its performance is comparable to those already cleared devices.

Parameter Measured (Implicit Performance Standard: Substantial Equivalence to Predicate Devices)	Reported Device Performance (Implied by Substantial Equivalence)
WBC (Leukocyte count)	Performance comparable to COULTER® Ac-T diff™ Analyzer (K973634) and COULTER® COUNTER® S-PLUS IV and LYSE S PLUS D (K823335)
LY # (Lymphocyte number)	As above
LY% (Lymphocyte percent)	As above
MO # (Mononuclear number)	As above
MO % (Mononuclear percent)	As above
GR # (Granulocyte number)	As above
GR % (Granulocyte percent)	As above
RBC (Erythrocyte count)	As above
Hgb (Hemoglobin)	As above
Hct (Hematocrit)	As above
MCV (Mean Corpuscular Volume)	As above
MCH (Mean Corpuscular Hemoglobin)	As above
MCHC (Mean Corpuscular Hemoglobin Concentration)	As above
Plt (Platelet or thrombocyte count)	As above
RDW (Red Cell Distribution Width)	As above
MPV (Mean Platelet (thrombocyte) Volume)	As above
Pct* (Plateletcrit)	As above (*Note: Not for diagnostic use)
PDW* (Platelet Distribution Width)	As above (*Note: Not for diagnostic use)
Three-population leukocyte count (LY %, MO%, GR %) from WBC histogram based on cell size	As above

2. Sample Size Used for the Test Set and Data Provenance

The document does not provide details about a specific test set, its sample size, or data provenance (e.g., country of origin, retrospective/prospective) for the Ac-T diff 2 device. The submission relies on demonstrating substantial equivalence to predicate devices, rather than presenting a de novo performance study with a new dataset.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of those Experts

This information is not provided in the document. As a 510(k) submission, the focus is on technological similarity to existing devices, not on a new clinical study requiring independent expert ground truth establishment for novel algorithms.

4. Adjudication Method for the Test Set

This information is not provided in the document.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

No MRMC study is mentioned or implied. The device is an automated hematology analyzer, not a diagnostic imaging AI system that typically involves human readers.

6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study

The device itself is a standalone automated hematology analyzer. Its performance is inherent to its operation as described, without human intervention in the analysis process (though human interpretation of results is part of clinical use). However, the document does not present a specific standalone study for the Ac-T diff 2 device; it focuses on its substantial equivalence to prior predicate devices.

7. Type of Ground Truth Used

The document does not explicitly state the type of ground truth used for any specific performance study of the Ac-T diff 2. Given it's a hematology analyzer, "ground truth" for its parameters (e.g., cell counts, hemoglobin) would typically be established through reference methods, manual microscopy, or highly characterized control materials, which are standard for predicate devices of this type. The Ac-T diff 2 is presented as technically equivalent to these established devices.

8. Sample Size for the Training Set

No training set or associated sample size is mentioned. This device is a traditional automated analyzer based on physical principles (Coulter principle, photometry), not a machine learning or AI algorithm that typically has a "training set."

9. How the Ground Truth for the Training Set Was Established

Not applicable, as no training set for a machine learning model is mentioned.

Summary

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4/1/99

K990352

Summary of Safety & Effectiveness COULTER® AC.T diff 2rw Analyzer

1.0 Submitted By

Tom Enalish Manager, Premarket Product Regulatory Compliance Coulter Corporation 11800 SW 147 Avenue MC 31-B06 Miami, FL 33196 Telephone: (305) 380-4331 FAX: (305) 380-3618

2.0 Date Submitted

January 27, 1999

3.0 Device Name(s)

3.1 Proprietary Names

COULTER® Ac·T diff 2™ Analyzer

3.2 Classification Names

An automated differential cell counter is a device used to identify and classify one or more of the formed elements of blood. (CFR 864.5220)

4.0 Predicate Device(s)

COULTER® Ac-T diff™ Analyzer (K973634) COULTER® COUNTER® S-PLUS IV and LYSE S PLUS D (K823355)

5.0 Description

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All the devices determine the following CBC parameters:

WBC	(Leukocyte count)
LY #	(Lymphocyte number)
LY%	(Lymphocyte percent)
MO #	(Mononuclear number)
MO %	(Mononuclear percent)
GR #	(Granulocyte number)
GR %	(Granulocyte percent)
RBC	(Erythrocyte count)
Hgb	(Hemoglobin)
Hct	(Hematocrit)
MCV	(Mean Corpuscular Volume)
MCH	(Mean Corpuscular Hemoglobin)
MCHC	(Mean Corpuscular Hemoglobin Concentration)
Plt	(Platelet or thrombocyte count)
RDW	(Red Cell Distribution Width)
MPV	Mean Platelet (thrombocyte) Volume
Pct*	Plateletcrit
PDW*	Platelet Distribution Width

*These parameters are not for diagnostic use but can be used as internal instrument checks on the platelet parameters.

6.0 Intended Use:

The COULTER® Ac-T diff 2 analyzer is a quantitative, automated hematology analyzer and leukocyte differential counter intended For In Vitro Diagnostic Use in clinical laboratories.

7.0 Comparison to Predicate(s):

The following tables outline the basic similarities and differences between the Ac-T diff 2 analyzer and the predicate devices.

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Public Health Service

Image /page/3/Picture/2 description: The image is a black and white seal for the Department of Health & Human Services - USA. The seal is circular with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the edge. In the center of the seal is an abstract image of an eagle.

APR 1 1999 Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Mr. Tom English Manager, Premarket Product Regulatory Compliance Coulter Corporation 11800 SW 147 Avenue MC 31-B06 Miami. Florida 33196

Re: K990352 Trade Name: COULTER® Ac-T diff 2™ Analyzer Regulatory Class: II Product Code: GKZ Dated: January 27, 1999 Received: February 5, 1999

Dear Mr. English:

We have reviewed your Section 510(k) notification of intent to market the device referenced above and we 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). 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.

If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.

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Under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88), this device may require a CLIA complexity categorization. To determine if it does, you should contact the Centers for Disease Control and Prevention (CDC) at (770) 488-7655.

This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification"(21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsma/dsmamain.html".

Sincerely yours,

Steven Sutman

Steven I. Gutman, M.D. M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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INDICATIONS FOR USE STATEMENT

K990352
TO BE ASSIGNED

510(k) Number (if known):

Device Name: COULTER® AC.T diff 2ru Analyzer

Indications For Use:

The COULTER® AC T diff 2m analyzer is a quantitative, automated hematology analyzer and leukocyte differential counter For In Vitro Diagnostic Use in clinical laboratories.

21 CFR 864.5220 Automated differential cell counter

An automated differential cell counter is a device used to identify and classify one or more of the formed elements of blood.

(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

(Division Sign-Off)

(Division Sign-Off)
Division of Clinical Laboratory Devices K990352
510(k) Number

Prescription Use
(Per 21 CFR 801.109)

Over-The-Counter Use _

(Optional Form 1-2-96)

Regulation Number and Section

§ 864.5220 Automated differential cell counter.

(a)
Identification. An automated differential cell counter is a device used to identify one or more of the formed elements of the blood. The device may also have the capability to flag, count, or classify immature or abnormal hematopoietic cells of the blood, bone marrow, or other body fluids. These devices may combine an electronic particle counting method, optical method, or a flow cytometric method utilizing monoclonal CD (cluster designation) markers. The device includes accessory CD markers.(b)
Classification. Class II (special controls). The special control for this device is the FDA document entitled “Class II Special Controls Guidance Document: Premarket Notifications for Automated Differential Cell Counters for Immature or Abnormal Blood Cells; Final Guidance for Industry and FDA.”

COULTER® AC-T diff 2™ Analyzer	COULTER®AC-T diff™ Analyzer	COULTER® S-PLUS IV with Diff®
Utilizes the Coulter principle for enumeration and	Utilizes the Coulter principle for enumeration and	Utilizes the Coulter principle for enumeration and
sizing of blood cells.	sizing of blood cells.	sizing of blood cells.
Utilizes an automatic sampling, diluting and	Utilizes an automatic sampling, diluting and	Utilizes an automatic sampling, diluting and
mixing device for sample processing.	mixing device for sample processing.	mixing device for sample processing.
Reagent system includes isotonic diluent, lytic	Reagent system includes isotonic diluent, lytic	Reagent system includes isotonic diluent, lytic
reagent and cleaning agent.	reagent and cleaning agent.	reagent and cleaning agent.
Simultaneous analysis of RBC and WBC in	Simultaneous analysis of RBC and WBC in	Simultaneous analysis of RBC and WBC in
separate analysis vessels.	separate analysis vessels.	separate analysis vessels.
Utilizes sweep flow to prevent cells from	Utilizes sweep flow to prevent cells from	Utilizes sweep flow to prevent cells from
re-entering the sensing zone and being counted as	re-entering the sensing zone and being counted as	re-entering the sensing zone and being counted as
platelets.	platelets.	platelets.
Ability to set normal patient ranges against which	Ability to set normal patient ranges against which	Ability to set normal patient ranges against which
sample results are compared. Sample results are	sample results are compared. Sample results are	sample results are compared. Sample results are
flagged with "H" if the result is above the normal	flagged with "H" if the result is above the normal	flagged with "H" if the result is above the normal
range and "L" if below the normal range.	range and "L" if below the normal range.	range and "L" if below the normal range.
Uses a single aperture each for WBC and RBC	Uses a single aperture each for WBC and RBC	Uses three apertures each for WBC and RBC
counting and sizing.	counting and sizing.	counting and sizing.
Parameters: WBC, RBC, Hgb, Hct, MCV, MCH,	Parameters: WBC, RBC, Hgb, Hct, MCV, MCH,	Parameters: WBC, RBC, Hgb, Hct, MCV, MCH,
MCHC, Plt, LY % & LY #, MO% & MO #, GR %	MCHC, Plt, LY % & LY #, MO% & MO #, GR %	MCHC, Plt, LY % & LY #, MO% & MO #, GR %
& GR #, RDW, MPV. Pct and PDW are also	& GR #, RDW, MPV. Pct and PDW are also	& GR #, RDW, MPV. Pct and PDW are also
measured but not intended for diagnostic use.	measured but not intended for diagnostic use.	measured but not intended for diagnostic use.
Instrument calculates a three-population leukocyte	Instrument calculates a three-population leukocyte	Instrument calculates a three-population leukocyte
count (LY %, MO%, GR %) from the WBC	count (LY %, MO%, GR %) from the WBC	count (LY %, MO%, GR %) from the WBC
histogram based on cell size. Cells between 35 fL	histogram based on cell size. Cells between 35 fL	histogram based on cell size. Cells between 35 fL
and 90 fL are classified as lymphocytes. The	and 90 fL are classified as lymphocytes. The	and 90 fL are classified as lymphocytes. The
absolute number for each population is then	absolute number for each population is then	absolute number for each population is then
compared	compared	compared
Ability to store data.	Ability to store data.	Ability to store data.
Automated Calibration and Control calculations,	Automated Calibration and Control calculations.	Automated Calibration and Control calculations.
Automated, self-cleaning probe.	Automated, self-cleaning probe.	See DIFFERENCES table
Uses Universal Icons for operator interface.	Uses Universal Icons for operator interface.	See DIFFERENCES table.