The SHIGA TOXIN CHEK test is an enzyme immunoassay for the simultaneous qualitative detection of Shiga toxin 1 (Stx1) and Shiga toxin 2 (Stx2) in a single test. It is intended for use with human fecal samples from patients with gastrointestinal symptoms to aid in the diagnosis of disease caused by Shiga Toxin producing Escherichia coli (STEC). It may be used directly with human fecal specimens, or broth or plate cultures derived from fecal specimens. The test results should be considered in conjunction with the patient history. FOR IN VITRO DIAGNOSTIC USE.

Device Description

The SHIGA TOXIN CHEK test uses antibodies to Stx1 and Stx2. The microassay wells supplied with the kit contain immobilized monoclonal antibodies against Stx1 and Stx2. The detecting antibody consists of a mixture of anti-Stx1 and anti-Stx2 polyclonal antibodies conjugated to horseradish peroxidase. In the assay, an aliquot of a fecal specimen or culture is emulsified in the Diluent and the diluted specimen is then transferred to the microassay well containing the detecting antibody. If Stx1 and/or Stx2 are present in the specimen, they will bind to the detecting antibody and to the immobilized monoclonal antibodies during the incubation phase. Any unbound material is removed during the washing steps. Following the addition of substrate, a color is detected due to the enzyme-antibody-antigen complexes that form in the presence of toxin.

AI/ML Overview

The SHIGA TOXIN CHEK test is an enzyme immunoassay for the simultaneous qualitative detection of Shiga toxin 1 (Stx1) and Shiga toxin 2 (Stx2). It is intended for use with human fecal samples from patients with gastrointestinal symptoms to aid in the diagnosis of disease caused by Shiga Toxin producing Escherichia coli (STEC).

Here's the breakdown of acceptance criteria and the study results:

1. Table of Acceptance Criteria and Reported Device Performance

Performance Metric	Acceptance Criteria (Implicit)	Reported Device Performance (Direct Fecal Testing)	Reported Device Performance (Broth Cultures)
Sensitivity	High (e.g., >95%)	100%	97.1%
Specificity	High (e.g., >95%)	99.9%	99.7%
Correlation	High (e.g., >95%)	99.9%	99.5%
Reproducibility	100% agreement	100% agreement	Not explicitly stated for broth cultures (but for overall test)
Analytical Sensitivity (LOD) for Stx1 (direct fecal)	Should detect low concentrations	0.28 ng/mL	N/A
Analytical Sensitivity (LOD) for Stx2 (direct fecal)	Should detect low concentrations	0.23 ng/mL	N/A
Analytical Sensitivity (LOD) for Stx1 (broth cultures)	Should detect low concentrations	N/A	0.18 ng/mL
Analytical Sensitivity (LOD) for Stx2 (broth cultures)	Should detect low concentrations	N/A	0.30 ng/mL
Analytical Specificity (Cross-Reactivity)	No interference from common bacterial/viral strains	No interference	No interference
Precision - Intra-Assay	Positive remain positive, negative remain negative	100% (positives remained positive, negatives remained negative)	Not explicitly stated for broth cultures (but for overall test)
Precision - Inter-Assay	Positive remain positive, negative remain negative	100% (positives remained positive, negatives remained negative)	Not explicitly stated for broth cultures (but for overall test)

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

Clinical Performance - Direct Fecal Testing:
- Sample Size: 913 samples (899 fresh and 14 frozen specimens).
- Data Provenance: Not explicitly stated, but clinical performance was evaluated at 3 independent sites, suggesting a mix of retrospective and prospective clinical samples. The origin country is not specified.
Clinical Performance - Broth Cultures:
- Sample Size: 789 samples.
- Data Provenance: Not explicitly stated, but clinical performance was evaluated at 3 independent sites, suggesting a mix of retrospective and prospective clinical samples. The origin country is not specified.
Reproducibility:
- Sample Size: 11 fecal specimens (coded to prevent identification).
- Data Provenance: Tested at 2 independent laboratories and on-site at TECHLAB®, Inc.
Analytical Sensitivity (LOD):
- Sample Size: Replicates of 20 for each toxin dilution in a negative fecal pool (direct fecal) or overnight GN broth culture (broth cultures).
- Data Provenance: Laboratory controlled experiments using highly purified Stx1 and Stx2.
Analytical Specificity (Cross Reactivity):
- Sample Size: A panel of various bacterial and viral strains.
- Data Provenance: Laboratory controlled experiments.
Precision - Intra-Assay:
- Sample Size: 6 positive fecal specimens and 6 negative fecal specimens, each assayed in replicates of eight.
- Data Provenance: Laboratory controlled experiments.
Precision - Inter-Assay:
- Sample Size: 12 fecal specimens (six negative, two positive for Stx1, two positive for Stx2, and two positive for both Stx1 and Stx2).
- Data Provenance: Laboratory controlled experiments.

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

The ground truth for the clinical performance studies (Direct Fecal Testing and Broth Cultures) was established using the Vero Cell Cytotoxin Assay with neutralization. This is referred to as the "Clinical Reference Standard (Gold Standard)" in the document.

Number of Experts: Not specified. The Vero Cell Cytotoxin Assay is a laboratory-based method, and its interpretation would typically be performed by trained laboratory personnel.
Qualifications of Experts: Not specified. It's implied that trained microbiologists or laboratory technicians would perform and interpret the gold standard assay.

4. Adjudication Method for the Test Set

The document does not explicitly describe an adjudication method for discrepancies between the SHIGA TOXIN CHEK test and the Vero Cell Cytotoxin Assay. The results provided are direct comparisons. For example, in the direct fecal testing, 78 samples were positive by both methods, 1 was positive by SHIGA TOXIN CHEK and negative by the cytotoxin assay, and 0 were negative by SHIGA TOXIN CHEK and positive by the cytotoxin assay. This suggests that the cytotoxin assay was considered the definitive ground truth, and no further adjudication process is mentioned for conflicting results.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

This information is not applicable to the SHIGA TOXIN CHEK device. This is an enzyme immunoassay for detecting toxins, not an imaging or diagnostic device that involves human "readers" in the context of interpretation that could be assisted by AI. The device directly produces a qualitative (positive/negative) result based on an enzymatic reaction and color change.

6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done

The SHIGA TOXIN CHEK is a standalone device in that its performance metrics (sensitivity, specificity, correlation) are reported directly against the gold standard (Vero Cell Cytotoxin Assay) without a human interpretation step that would then be assisted by the device. The device itself performs the detection. The results are read based on a colorimetric reaction, which is then interpreted as positive or negative. The "study" (clinical performance) focuses on the device's accuracy in identifying the presence of the toxins compared to the established gold standard.

7. The Type of Ground Truth Used

The primary ground truth used for the clinical performance studies was the Vero Cell Cytotoxin Assay with neutralization, described as the "Clinical Reference Standard (Gold Standard)".

For analytical studies (LOD, cross-reactivity, precision), the ground truth was established through controlled laboratory experiments using known concentrations of purified toxins or specific bacterial/viral strains.

8. The Sample Size for the Training Set

The document does not explicitly mention a "training set" in the context of machine learning or AI models. This device is an immunoassay, and its development would typically involve optimization and validation rather than a distinct "training set" for an algorithm. The clinical and analytical studies serve as validation of the device's performance.

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

As there is no explicit "training set" described in the context of an AI/ML model for this immunoassay, this question is not applicable. The ground truth for the validation (test) sets was established using the Vero Cell Cytotoxin Assay with neutralization.

Summary

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Image /page/0/Picture/0 description: The image shows the word "TECHLAB" in bold, black letters inside of a black oval. The word is all capitalized, and there is a small dot after the "B". The oval is thin and surrounds the word closely.

K121411

OCT

2 2012

SHIGA TOXIN CHEK 510(k) SUMMARY

This summary of 510(k) safety and effectiveness is being submitted in accordance with the requirements of 21 CFR 807.92.

Applicant/Contact Information:

Date Prepared: Name: Address:

August 30, 2012 TECHLAB®, Inc. 2001 Kraft Drive Corporate Research Center Blacksburg, VA 24060

Contact Person: Phone Number: Email:

Donna T. Link 540-953-1664

Signature:

ber: 540-953-1664
dlink@techlab.com

1.1 Manufacturing Facility Address

TECHLAB®, Inc. 2001 Kraft Drive Blacksburg, VA 24060-6358

1.2 Product and Trade Name of the Device

SHIGA TOXIN CHEK

1.3 Common Name or Classification Name

E. coli toxins detection test

1.4 Classification and Regulation

Class I 21 CFR 866.3255; Escherichia coli serological reagents

1.5 Product Code(s)

GMZ - Antigens, all types, Escherichia coli

1.6 Panel

83 Microbiology

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Intended Use

Explanation

Shiga toxin producing Escherichia coli (STEC) were first described by O' Brien, et al. after discovering that E. coli culture supernatant, which was cytotoxic to HeLa and Vero cells, could be neutralized by rabbit antibodies. STEC cause foodborne and waterborne diarrheal disease worldwide which, if left undiagnosed, can progress to hemorrhagic colitis and/or hemolytic uremic syndrome (HUS). Since certain treatments and medications can increase the risk of HUS, prompt detection is necessary to prevent outbreaks and secondary transmission. STEC strain O157:H7 has historically been the focus of attention in the United States since first isolated from undercooked hamburgers, causing an estimated 73,000 illnesses annually. However, STEC infections caused by non-0157 strains have become more prevalent in recent years, both in the United States as well as abroad. 0157:H7 infections are routinely diagnosed by culture of fecal samples on selective methodology allows non-O157 STEC strains to go undetected. STEC produce either one or both Shiga toxins (Stx1 and/or Stx2), both potent cytotoxins. Isolates producing only Stx2 have been attributed to higher incidence rates of HUS. Shiga toxins can be detected by tissue culture assay, but this method is both time consuming and labor intensive. By detecting the SHIGA TOXIN CHEK test can detect STEC present in fecal samples or culture, regardless of the serotype or other virulence factors.

Device Description

Materials Provided

Microassay Plate - 12 strips, each strip consisting of 8 wells, coated with monoclonal antibodies specific for Stx1 and Stx2 (stored with desiccant)

Diluent (40 mL) - buffered protein solution containing 0.02% thimerosal

Substrate (14 mL) - solution containing tetramethylbenzidine and peroxide

Wash Buffer Concentrate (50 mL) - 20X concentrate containing phosphate buffered saline, detergent, and 0.2% thimerosal

Stop Solution (7 mL) - 0.6N sulfuric acid

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Positive Control (3.5 mL) - inactivated antigen in a buffered protein solution containing amphotericin B Conjugate (7 mL) – polyclonal antibodies specific for Stx1 and Stx2 coupled to horseradish peroxidase in a buffered protein solution containing 0.02% thimerosal Disposable plastic pipettes - graduated at 50 µL, 100 µL, 200 µL and 300 µL Plastic Adhesive Sheets – Quantity 2 Wash Label – Quantity 1 [IVD] In Vitro Diagnostic Medical Device

Comparative Information of Predicate Devices

Kit Name	510(k)Numbers	Intended Use	Format	Target Population
Vero Cell CytotoxinAssay (withneutralization)*	ClinicalReferenceStandard(goldstandard)	Detection of Shigatoxins 1 and 2 fromfecal specimens, brothcultures, individualcolonies or colonysweeps of agar plates	Cell culturecytotoxicity andneutralization	Persons suspected ofhaving STEC infection
Premier™ EHEC	K953362	Detection of Shigatoxins 1 and 2 fromdirect fecal samples,broth cultures of fecalspecimens, individualcolonies or colonysweeps of agar plates	Microwell ELISA	Persons suspected ofhaving STEC infection
ImmunoCard Stat!EHEC	K062546	Detection of Shigatoxins 1 and 2 incultures derived fromclinical stool specimens	Immuno-chromatographicrapid test	Persons suspected ofhaving STEC infection
ProSpecT ShigaToxin E. coli (EHEC)Microplate ELISA	K980507	Detection of Shigatoxins (Stx1 and Stx2)in aqueous extracts offecal specimens andbroth enriched fecalcultures	Microplate ELISA	Persons suspected ofhaving STEC infection

*Comparative device used to establish equivalency.

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Similarities
ltem	SHIGA TOXIN CHEK	ImmunoCard STAT!EHECK062546	PREMIER EHECK953362	ProSpecT Shiga ToxinE. coli (STEC)K980507
IntendedUse	Qualitative Detection ofShiga toxins 1 and 2	Qualitative Detection ofShiga toxins 1 and 2	Qualitative Detection ofShiga toxins 1 and 2	Qualitative Detection ofShiga toxins 1 and 2
Technology	Immunoassay	Immunoassay	Immunoassay	Immunoassay
AntibodyFormat	Monoclonal/Polyclonal	Monoclonal/Polyclonal	Monoclonal/Polyclonal	Monoclonal/Polyclonal

Differences
Item	SHIGA TOXINCHEK	ImmunoCard STAT!EHEC	PREMIER EHEC	ProSpecT ShigaToxin E. coli (STEC)
Intended Use	Non-differentiation	Differentiation	Non-differentiation	Non-differentiation
Technology	EnzymeImmunoassay -Microwell PlateELISA	Immunochromatographic(lateral flow)	Enzyme Immunoassay- Microwell PlateELISA	Enzyme Immunoassay- Microwell PlateELISA
SpecimenTypes	Direct Human FecalSpecimensBroth CulturesPlate cultures	Broth and Plate Culturesonly	Direct Human FecalSpecimensBroth culturesPlate cultures	Direct Human FecalSpecimensBroth cultures
Amount ofSpecimenrequired	50 µL - fecal or brothculture100 µL - transportmedia	50 µL - fecal	50 µL - fecal	300 µL - fecal
Time to Result	60 minutes oralternate rapid 30minutes	25 minutesafter the 16-24 hr.enrichment procedure	2 hour 15 minutes	1 hour 50 minutes

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Summary of Performance Data

Predicate Device Method Comparison N/A

Other Method Comparison - Clinical Reference Standard (Gold Standard)

Vero Cell Cytotoxin Assay with neutralization

Clinical Performance

The performance of the SHIGA TOXIN CHEK test was evaluated at 3 independent sites. A summary of overall performance at the 3 sites follows.

Direct Fecal Testing

The performance of the SHIGA TOXIN CHEK test was compared to the Vero Cell Cytotoxin Assay (with neutralization) and included 899 fresh and 14 frozen specimens. The following table shows a summary of the clinical performance of the SHIGA TOXIN CHEK test. The results show that the SHIGA TOXIN CHEK test exhibited a sensitivity of 100%, a specificity of 99.9%, and an overall correlation of 99.9% with the cytotoxin assay.

SHIGA TOXIN CHEK Test Versus the Vero Cell Cytotoxicity Assay

N = 913	Vero Cell CytotoxicityAssay Positive	Vero Cell CytotoxicityAssay Negative
SHIGA TOXIN CHEK Positive	78	1
SHIGA TOXIN CHEK Negative	0	834

		95% Confidence Limits
Sensitivity	100%	94.2 - 100%
Specificity	99.9%	99.2 - 100%
Correlation	99.9%	100 - 100%

Broth Cultures

The performance of the SHIGA TOXIN CHEK test using overnight broth cultures (GN or MacConkey broth) from fecal specimens was compared to the Vero Cell Cytotoxin Assay. The following table shows a summary of the clinical performance of the SHIGA TOXIN CHEK test. The results show that the SHIGA TOXIN CHEK test exhibited a sensitivity of 97.1%, a specificity of 99.7%, and an overall correlation of 99.5% with the cytotoxin assay.

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SHIGA TOXIN CHEK Test Versus the Vero Cell Cytotoxicity Assay

N = 789	Vero Cell CytotoxicityAssay Positive	Vero Cell CytotoxicityAssay Negative
SHIGA TOXIN CHEK Positive	67	2
SHIGA TOXIN CHEK Negative	2	718

		95% Confidence Limits
Sensitivity	97.1%	89.0 - 99.5%
Specificity	99.7%	98.9 - 99.9%
Correlation	99.5%	99.5 - 99.5%

Reproducibility

The reproducibility of the SHIGA TOXIN CHEK test was determined using 11 fecal specimens that were coded to prevent their identification during testing. Testing was performed at 2 independent laboratories and on-site at TECHLAB®, Inc. The samples were tested, twice a day over a 5-day period by multiple technicians at each site using 2 different kit lots. A positive and negative control was run with each panel of the masked samples. The results from each
laboratory were submitted to TECHLAB®, Inc. and compared with in-house results. Th were consistent among the different locations, and exhibited a correlation of 100%. The samples produced the expected results 100% of the time.

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Analytical Sensitivity

The cutoff for the SHIGA TOXIN CHEK test for direct fecal specimens was established at concentrations of 0.28 ng/mL Stx1 and 0.23 ng/mL Stx2, and for broth cultures at concentrations of 0.18 ng/mL Stx1 and 0.30 ng/mL Stx2.

Determination of Limitation of Detection (LOD) - cutoff points for Stx1 and Stx2 directly from fecal specimens:

The results were determined following EP17A - "Protocols for Determination of Limits of Detection and Limits of Quantitation; Approved Guideline".

The cutoff point for Stx1 was determined by using highly purified Stx1, and was defined as the concentration of toxin which vielded positive results 95% of the time, and negative results 5% of the time. The cutoff point was determined empirically by testing dilutions of Stx1 in a neqative fecal pool, in replicates of 20. Using this method, the cutoff was found to be 0.280 ng/mL. A concentration of 0.275 ng/mL was positive 50% of the time, and a concentration of 0.260 ng/mL was negative 95% of the time.

The cutoff point for Stx2 was determined by using highly purified Stx2, and was defined as the concentration of toxin which vielded positive results 95% of the time, and negative results 5% of the time. The cutoff point was determined empirically by testing dilutions of Stx2 in a negative fecal pool, in replicates of 20. Using this method, the cutoff was found to be 0.230 ng/mL. A concentration of 0.200 ng/mL was positive 50% of the time, and a concentration of 0.150 ng/mL was negative 95% of the time.

Determination of Limitation of Detection (LOD) - cutoff points for Stx1 and Stx2 from broth cultures:

The results were determined following EP17A - "Protocols for Determination of Limits of Detection and Limits of Quantitation; Approved Guideline".

The cutoff point for Stx1 was determined by using highly purified Stx1, and was defined as the concentration of toxin which yielded positive results 95% of the time, and negative results 5% of the time. The cutoff point was determined empirically by testing dilutions of Stx1 in overnight GN broth culture of non-toxin producing E. Coli O157 (ATCC 043888), in replicates of 20. Using this method, the cutoff was found to be 0.180 ng/mL. A concentration of 0.120 ng/mL was positive 50% of the time, and a concentration of 0.110 ng/mL was negative 95% of the time.

The cutoff point for Stx2 was determined by using highly purified Stx2, and was defined as the concentration of toxin which yielded positive results 95% of the time, and negative results 5% of the time. The cutoff point was determined empirically by testing dilutions of Stx2 in overnight GN broth culture of non-toxin producing E. Coli O157 (ATCC 04388), in replicates of 20. Using this method, the cutoff was found to be 0.300 ng/mL. A concentration of 0.200 ng/mL was positive 50% of the time, and a concentration of 0.170 ng/mL was negative 95% of the time.

In conclusion, the data generated for Determination of Limitation of Detection (LOD), support Package Insert claims of analytical sensitivity for direct fecal specimens was established at concentrations of 0.28 ng/mL Stx1 and 0.23 ng/mL Stx2, and for broth cultures at concentrations of 0.18 ng/mL Stx1 and 0.30 ng/mL Stx2.

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Analytical Specificity (Cross Reactivity)

The SHIGA TOXIN CHEK test was evaluated for cross-reactivity with the bacterial and viral strains listed below. None of the strains were shown to interfere with the performance SH/GA TOXIN CHEK test.

Aeromonas hydrophila	Campylobacter coli	Campylobacter fetus
Campylobacter jejuni	Candida albicans	Citrobacter freundii
Clostridium difficile	Clostridium perfringens	Enterobacter cloacae
Enterococcus faecalis	Escherichia coli (non-toxigenic)	Escherichia coli O157:H7 (non-toxigenic)
Escherichia coli EIEC (enteroinvasive)	Escherichia coli EPEC (enteropathogenic)	Escherichia coli ETEC (enterotoxic)
Escherichia fergusonii	Escherichia hermannii	Gardnerella vaginalis
Helicobacter pylori	Klebsiella pneumoniae	Lactobacillus acidophilus
Proteus vulgaris	Providencia stuartii	Pseudomonas aeruginosa
Pseudomonas fluorescens	Salmonella enteric serovar minnesota	Salmonella typhimurium
Serratia liquefacians	Shigella flexneri	Shigella sonnei
Staphylococcus aureus	Staphylococcus aureus (Cowan)	Staphylococcus epidermidis
Yersinia enterocolitica

Human Adenovirus, Type 2, 14, 40 and 41 Human Coxsackievirus A9, B1 Feline calicvirus

Human rotavirus

Human Enterovirus 69

Strains/Serotypes

Various E. coli Shiga toxin-producing strains and serotypes were tested in the SHIGA TOXIN CHEK test by both the Sorbitol MacConkey Agar (SMAC) plate and MacConkey broth culture methods. Escherichia coli 0157 strains were also tested using CT-SMAC and ChromAgar 0157 plate cultures. Each strain is a clinical isolate and each was tested by a cytotoxin assay and by a polymerase chain reaction (PCR) to confirm the presence of the Shiga toxin gene(s). All organisms generated positive results for the appropriate toxin(s) when tested. Following is a list of the serotypes tested, the number of strains tested in that group type and the type of toxin produced by each strain.

Shiga Toxin Type Stx1: Strain Types - O26:H11 (5 strains), O157:H7, O111:NM (2 strains), 0103:H2, O103:H25, O103:H6, O103:N, O111:H11, O111:H8, O145:NM, O45:H2 (4 strains), 045:NM, 0125:NM, 0146:H21, 0156:H21, 026, 05:N, 070:H111, 0111a:NM

Shiga Toxin Type Stx2: Strain Types - 157:H7 (6 strains), O104:H4 (European 2011 outbreak strain), 0177:NM, 06:H10. 0121:H19 (3 strains), 0121. 0145:H28. 0145. 0113:H21. 0104:H21, O55:H7, O91:H21, O6:H10

Shiga Toxin Type Stx1 and Stx2: Strain Types - O157:H7 (8 strains), O157:NM (2 strains), 0111:H8, O111, O111:NM (2 strains), O113:H21, O15:H27

Interfering Substances (U.S. Formulations)

The following substances had no effect on positive or negative test results analyzed at the concentrations indicated: Hog gastric mucin (3.5% w/v), Human blood (40% v/v), Barium sulfate (5% w/v), Imodium® (5% v/v), Kaopectate® (5% v/v), Pepto-Bismol® (5% v/v), Maalox® Advanced (5% v/v), Steric Acid (40% w/v), Metronidazole (0.25% w/v), Vancomycin (0.25% w/v), Priolsec OTC® (5 µg/mL), TUMS (50 µg/mL), Tagamet® (5 µg/mL), Leukocytes (0.05% v/v), Ciprofloxacin (0.25% w/v).

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Precision - Intra-Assay

For the determination of intra-assay performance, 6 positive fecal specimens and 6 negative fecal specimens were analyzed. Each specimen was assayed in replicates of eight. All positives remained positive and all negatives remained negative.

Precision - Inter-Assay

The inter-assay precision of the SHIGA TOXIN CHEK test was determined using 12 fecal specimens (six negative, two positive for Stx1, two positive for Stx2, and two positive for both Stx1 and Stx2). The samples were tested, twice a day over a 5-day period using 2 different kit lots. A positive and negative control was run on each day. All positives remained positive and all negatives remained negative.

Conclusion

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

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DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/9/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the perimeter. Inside the circle is an abstract symbol resembling an eagle or bird in flight, composed of several curved lines.

Public Health Service

Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993

TECHLAB®, Inc. c/o Donna T. Link Director of OA, Regulatory & Compliance 2001 Kraft Drive Blacksburg, VA 24060-6358

Re: K121411

Trade/Device Name: SHIGA TOXIN CHEK Regulation Number: 21 CFR 866.3255 Regulation Name: Escherichia coli serological reagents Regulatory Class: Class I Product Code: GMZ Dated: September 26, 2012 Received: September 26, 2012

OCT 2 2012

Dear Ms. Link:

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.

If your device is classified (see above) into class II (Special Controls), it may be subject to such additional controls. Existing major regulations affecting your device can be found in Title 21, Code of Federal Regulations (CFR), Parts 800 to 895. 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 of medical device-related adverse events) (21 CFR 803); and good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820). This letter will allow you to begin marketing your device as described in your Section 510(k) premarket : notification. The FDA finding of substantial equivalence of your device to a legally marketed

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Page 2 - Donna T. Link

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 Parts 801 and 809), please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at (301) 796-5450. 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 Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address http://www.fda.gov/cdrh/industry/support/index.html.

Sincerely yours,
Uve Saif ta

Sally A. Hojvat, M.Sc., Ph.D. Director Division of Microbiology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health

Enclosure

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INDICATIONS FOR USE 2.

K 121411 510(k) Number:

Device Name:

SHIGA TOXIN CHEK

Indications For Use:

The SHIGA TOXIN CHEK test is an enzyme immunoassay for the simultaneous qualitative detection of Shiga toxin 1 (Stx1) and Shiga toxin 2 (Stx2) in a single test. It is intended for use with human fecal samples from patients with gastrointestinal symptoms to aid in the diagnosis of disease caused by Shiga Toxin producing Escherichia coli (STEC). It may be used directly with human fecal specimens, or broth ronin aroutures derived from fecal specimens. The test results should be considered in conjunction with the patient history.

FOR IN VITRO DIAGNOSTIC USE.

Prescription Use (Part 21 CFR 801 Subpart D) AND/OR

Over-The-Counter Use (21 CFR 807 Subpart C)

(Please Do Not WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of In Vitro Diagnostic Devices (OIVD)

Page 1 of _ 1

Ritha Shearer

Division Sign-off Office of In Vitro Diagnostic Device Evaluation and Safety

510(k) K121411

Page 1 of

Regulation Number and Section

§ 866.3255

Escherichia coli serological reagents.(a)
Identification. Escherichia coli serological reagents are devices that consist of antigens and antisera used in serological tests to identifyEscherichia coli from cultured isolates derived from clinical specimens. Additionally, some of these reagents consist ofEscherichia coli antisera conjugated with a fluorescent dye used to identifyEscherichia coli directly from clinical specimens or cultured isolates derived from clinical specimens. The identification aids in the diagnosis of diseases caused by this bacterium belonging to the genusEscherichia, and provides epidemiological information on diseases caused by this microorganism. AlthoughEscherichia coli constitutes the greater part of the microorganisms found in the intestinal tract in humans and is usually nonpathogenic, those strains which are pathogenic may cause urinary tract infections or epidemic diarrheal disease, especially in children.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 866.9.