C. DIFF QUIK CHEK

• K Number: K053572
• Device Name: C. DIFF QUIK CHEK
• Manufacturer: TECHLAB, INC.
• Date Cleared: 2006-04-26 ( 125 days)
• Product Code: MCB
• Regulation Number: 866.2660

Intended Use

The C. DIFF QUIK CHEK™ test is a rapid membrane enzyme immunoassay for use as a screening test to detect Clostridium difficile antigen, glutamate dehydrogenase, in fecal specimens from persons suspected of having C. difficile disease. The test does not distinguish toxigenic from nontoxigenic strains of C. difficile. With the use of additional tests that detect C. difficile toxins, the test is to be used as an aid in the diagnosis of C. difficile disease. As with other C. difficile tests, results should be considered in conjunction with the patient history. FOR IN VITRO DIAGNOSTIC USE.

Device Description

The C. DIFF QUIK CHEK™ test uses antibodies specific for glutamate dehydrogenase (GDH) of C. difficile. The device contains a Reaction Window with two lines of immobilized antibodies. The test line ("T") contains antibodies against C. difficile GDH. The other, representing a control line ("C"), contains anti-IgG antibodies. The Conjugate consists of antibody to GDH coupled to horseradish peroxidase. To perform the test, the fecal specimen is diluted with Diluent, and Conjugate is added to the diluted sample. The diluted sample conjugate mixture is added to the Sample Well and the device is allowed to incubate at room temperature for 15 minutes. During the incubation, any GDH in the sample binds to antibodyperoxidase conjugate. The antigen-antibody complexes migrate through a filter pad to a membrane where they are captured by the immobilized anti-GDH antibody in the line. The Reaction Window is subsequently washed with Wash Buffer, followed by the addition of Substrate. After up to a 10-minute incubation, the "T" reaction is examined visually for the appearance of a blue line indicates a positive test. A positive "C" reaction, indicated by a blue line, confirms that sample and all reagents were added in proper sequence and volume, that reagents were active at the time of performing the assay, and that proper sample migration occurred.

Predicate Devices

K030992, K030991, K870864, K974881, K924979

Reference Devices

Not Found

AI/ML (Artificial Intelligence / Machine Learning)

No
The device description details a standard enzyme immunoassay with visual interpretation, and there is no mention of AI or ML in the text.

Therapeutic

No

The device is an in vitro diagnostic test designed to detect Clostridium difficile antigen in fecal specimens for screening and aid in diagnosis, not to treat a condition.

Diagnostic

Yes

The "Intended Use / Indications for Use" section explicitly states that the test is "to be used as an aid in the diagnosis of C. difficile disease" and "FOR IN VITRO DIAGNOSTIC USE."

SaMD (Software as a Medical Device)

No

The device description clearly outlines a physical, in vitro diagnostic test kit involving antibodies, membranes, reagents, and visual interpretation of color changes. It is a hardware-based assay, not software.

IVD (In Vitro Diagnostic)

Yes, this device is an IVD (In Vitro Diagnostic).

The text explicitly states: "FOR IN VITRO DIAGNOSTIC USE."

Furthermore, the description of the device and its intended use aligns with the definition of an IVD: it is a test performed on a biological specimen (fecal specimens) outside of the body to provide information for the diagnosis of a disease (C. difficile disease).

PCCP (Predetermined Change Control Plan) Authorized

N/A

Overview

Intended Use / Indications for Use

The C. DIFF QUIK CHEK™ test is a rapid membrane enzyme immunoassay for use as a screening test to detect Clostridium difficile antigen, glutamate dehydrogenase, in fecal specimens from persons suspected of having C. difficile disease. The test does not distinguish toxigenic from nontoxigenic strains of C. difficile. With the use of additional tests that detect C. difficile toxins, the test is to be used as an aid in the diagnosis of C. difficile disease. As with other C. difficile tests, results should be considered in conjunction with the patient history.

FOR IN VITRO DIAGNOSTIC USE.

Product codes

MCB

Device Description

The C. DIFF QUIK CHEK™ test uses antibodies specific for glutamate dehydrogenase (GDH) of C. difficile. The device contains a Reaction Window with two lines of immobilized antibodies. The test line ("T") contains antibodies against C. difficile GDH. The other, representing a control line ("C"), contains anti-IgG antibodies. The Conjugate consists of antibody to GDH coupled to horseradish peroxidase. To perform the test, the fecal specimen is diluted with Diluent, and Conjugate is added to the diluted sample conjugate mixture is added to the Sample Well and the device is allowed to incubate at room temperature for 15 minutes. During the incubation, any GDH in the sample binds to antibody-peroxidase conjugate. The antigen-antibody complexes migrate through a filter pad to a membrane where they are captured by the immobilized anti-GDH antibody in the line. The Reaction Window is subsequently washed with Wash Buffer, followed by the addition of Substrate. After up to a 10-minute incubation, the "T" reaction is examined visually for the appearance of a blue line indicates a positive test. A positive "C" reaction, indicated by a blue line, confirms that sample and all reagents were added in proper sequence and volume, that reagents were active at the time of performing the assay, and that proper sample migration occurred.

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)

The Tables below show a summary of the clinical performance of the C. DIFF QUIK CHEKTM test. Results from 3 studies are included in the summary. The discrepant samples generated from the C. DIFF QUIK CHEK™ test and the presumptive bacterial culture assay were resolved using a PCR assay, an ELISA for the antigen, or a membrane test for the antigen, as described in the individual studies. The protocols are included in Appendix A and D. The results show that the C. DIFF QUIK CHEK™ test exhibited a correlation of 92.6% with presumptive bacterial culture. When discrepant results were resolved by PCR, the correlation was 96.9%.

Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)

Clinical Performance Comparing C. DIFF QUIK CHEK™ Test to Presumptive Bacterial Culture (n=979):
Sensitivity: 92.8% (95% Confidence Limits: 88.3% - 95.7%)
Specificity: 92.6% (95% Confidence Limits: 90.4% - 94.3%)
Predictive Negative Value: 97.8% (95% Confidence Limits: 96.3% - 98.7%)
Correlation: 92.6% (95% Confidence Limits: 91.7% - 93.4%)

Clinical Performance of C. DIFF QUIK CHEK™ Test versus Bacterial Culture Assay after Resolution bv another GDH Test (n=979):
Predictive Negative Value: 99.6% (95% Confidence Limits: 98.7% - 99.9%)
Correlation: 96.9% (95% Confidence Limits: 96.5% - 97.2%)

Analytical Sensitivity:
The test was consistently positive at a concentration of 0.4 ng/mL for GDH.

Reproducibility:
A total of 8 fecal specimens, 6 positive and 2 negative, were coded to prevent identification and were sent to each of three independent laboratories for analysis using the C. DIFF QUIK CHEK™ test. The results from each laboratory were compared with in-house results. The results were consistent among the different locations, and exhibited a correlation of 100%. The positive specimens were confirmed to be positive and the negative specimens were confirmed to be negative at all sites using the C. DIFF QUIK CHEKTM test.

Predicate Device(s)

K030992, K030991, K870864, K974881, K924979

Reference Device(s)

Not Found

Predetermined Change Control Plan (PCCP) - All Relevant Information

Not Found

Regulation Number and Section

§ 866.2660 Microorganism differentiation and identification device.

(a)
Identification. A microorganism differentiation and identification device is a device intended for medical purposes that consists of one or more components, such as differential culture media, biochemical reagents, and paper discs or paper strips impregnated with test reagents, that are usually contained in individual compartments and used to differentiate and identify selected microorganisms. The device aids in the diagnosis of disease.(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 § 866.9.

Summary

0

Image /page/0/Picture/0 description: The image shows a handwritten string of characters, "K053572", in a bold, slightly irregular font. Below the string, there is a line of text that reads "C. DIFF QUIK CHEKTM 510(k)". The text is in a smaller, more formal font compared to the handwritten characters above it. The image appears to be a scan or a photograph of a document.

ារ​ប្រព័ន

7. 510(k) SUMMARY

| Contact Information | David M. Lyerly
Vice-President, Research & Development
TECHLAB®, Inc.
2001 Kraft Drive
Corporate Research Center
Blacksburg, VA 24060
Phone: [phone]
FAX: [phone]
Email: [e-mail] |
|------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Date Prepared | December 20, 2005 |
| Product and Trade Name | C. DIFF QUIK CHEKTM |
| Classification | 21 CFR 866.2660 |

Predicate Devices

• C. difficile Culture media such as cycloserine cefoxitin fructose agar (CCFA) is . available commercially from various sources.
• C. DIFF CHEK™ -- 60 (K030992) TECHLAB®, Inc. (Blacksburg, VA) .
• C. DIFF CHEK™ 30 (K030991) TECHLAB®, Inc. (Blacksburg, VA) .
• BD CULTURETTE™ CDT™ (K870864) Becton, Dickinson and Company . (Franklin Lakes, NJ)
• Triage® Micro Clostridium difficile Panel (K974881) Biosite Incorporated (San � Diego, CA)
• ImmunoCard® C. difficile EIA (K924979) Meridian Bioscience, Inc. (Cincinnati, . OH)

Intended Use

The C. DIFF QUIK CHEK™ test is a rapid membrane enzyme immunoassay for use as a screening test to detect Clostridium difficile antigen, glutamate dehydrogenase, in fecal specimens from persons suspected of having C. difficile disease. The test does not distinguish toxigenic from nontoxigenic strains of C. difficile. With the use of additional tests that detect C. difficile toxins, the test is to be used as an aid in the diagnosis of C. difficile disease. As with other C. difficile tests, results should be considered in conjunction with the patient history.

Device Description

The C. DIFF QUIK CHEK™ test uses antibodies specific for glutamate dehydrogenase (GDH) of C. difficile. The device contains a Reaction Window with two lines of immobilized antibodies. The test line ("T") contains antibodies against C. difficile GDH. The other, representing a control line ("C"), contains anti-IgG antibodies. The Conjugate consists of antibody to GDH coupled to horseradish peroxidase. To perform the test, the fecal specimen is diluted with Diluent, and Conjugate is added to the diluted sample. The diluted sample

1

conjugate mixture is added to the Sample Well and the device is allowed to incubate at room temperature for 15 minutes. During the incubation, any GDH in the sample binds to antibodyperoxidase conjugate. The antigen-antibody complexes migrate through a filter pad to a membrane where they are captured by the immobilized anti-GDH antibody in the line. The Reaction Window is subsequently washed with Wash Buffer, followed by the addition of Substrate. After up to a 10-minute incubation, the "T" reaction is examined visually for the appearance of a blue line indicates a positive test. A positive "C" reaction, indicated by a blue line, confirms that sample and all reagents were added in proper sequence and volume, that reagents were active at the time of performing the assay, and that proper sample migration occurred.

| Characteristics | 510(k)
Numbers | Intended Use | Format | Materials | Target
Population |
|-----------------------------------------------------|--------------------------------------------------|----------------------------------------------------------------|-------------------------------------|----------------------------------------------------------------------|-----------------------------------------------------------|
| C. DIFF QUIK
CHEK™ test | Subject to
this 510(k) | Detection of C.
difficile organism
in fecal
specimens | Rapid
membrane | Highly specific
antibodies
against C.
difficile GDH | Persons
suspected of
having C.
difficile disease |
| C. difficile
Presumptive
bacterial culture | Used before
1976,
510(k) not
available. | Detection of C.
difficile organism
in fecal
specimens | Bacterial
culture | Specific
selective
media, CCFAa
plates and CC
BHIb broth | Persons
suspected of
having C.
difficile disease |
| C. DIFF CHEK™

• 60 | K030992 | Detection of C.
  difficile organism
  in fecal
  specimens | ELISA | Highly specific
  antibodies
  against C.
  difficile GDH | Persons
  suspected of
  having C.
  difficile disease |
  | C. DIFF CHEK™
• 30 | K030991 | Detection of C.
  difficile organism
  in fecal
  specimens | ELISA | Highly specific
  antibodies
  against C.
  difficile GDH | Persons
  suspected of
  having C.
  difficile disease |
  | BD
  CULTURETTE™
  CDT™ | K870864 | Detection of C.
  difficile organism
  in fecal
  specimens | Latex
  agglutination | Antibodies
  against C.
  difficile GDH
  and other
  proteins | Persons
  suspected of
  having C.
  difficile disease |
  | Triage® Micro C.
  difficile Panel,
  GDH portion | K974881 | Detection of C.
  difficile organism
  in fecal
  specimens | Flow
  through
  membrane
  test | Highly specific
  antibodies
  against C.
  difficile GDH | Persons
  suspected of
  having C.
  difficile disease |
  | ImmunoCard® C.
  difficile EIA | K924979 | Detection of C.
  difficile organism
  in fecal
  specimens | Lateral flow
  membrane
  test | Highly specific
  antibodies
  against C.
  difficile GDH | Persons
  suspected of
  having C.
  difficile disease |

Comparative Information of Equivalent Devices

a, CCFA, cycloserine - cefoxitin fructose agar plates

b, CC-BHI, cycloserine - cefoxitin brain-heart infusion liquid media

2

Summary of Performance Data Clinical Accuracy

The Tables below show a summary of the clinical performance of the C. DIFF QUIK CHEKTM test. Results from 3 studies are included in the summary. The discrepant samples generated from the C. DIFF QUIK CHEK™ test and the presumptive bacterial culture assay were resolved using a PCR assay, an ELISA for the antigen, or a membrane test for the antigen, as described in the individual studies. The protocols are included in Appendix A and D. The results show that the C. DIFF QUIK CHEK™ test exhibited a correlation of 92.6% with presumptive bacterial culture. When discrepant results were resolved by PCR, the correlation was 96.9%.

Clinical Performance Comparing C. DIFF QUIK CHEK™ Test to Presumptive Bacterial Culture

| n=979 | Presumptive Bacterial
Culture positive | Presumptive Bacterial
Culture negative |
|------------------------------|-------------------------------------------|-------------------------------------------|
| C. DIFF QUIK CHEKTM positive | 206 | 56 |
| C. DIFF QUIK CHEKTM negative | 16 | 701 |

		95% Confidence Limits
Sensitivity	92.8%	88.3% - 95.7%
Specificity	92.6%	90.4% - 94.3%
Predictive Negative Value	97.8%	96.3% - 98.7%
Correlation	92.6%	91.7% - 93.4%

Twenty-nine of the 56 apparent false positive samples were positive by another GDH test, and were considered true positive. Twenty-seven remained false positive. Thirteen of the 16 apparent false negative samples were negative by another GDH test, and were considered true negative. Three remained false negative. The summary is presented below.

Clinical Performance of C. DIFF QUIK CHEK™ Test versus Bacterial Culture Assay after Resolution bv another GDH Test

| n=979 | Resolved Bacterial
Culture positive | Resolved Bacterial
Culture negative |
|-----------------------------|----------------------------------------|----------------------------------------|
| C. DIFF QUIK CHEK™ positive | 235 | 27 |
| C. DIFF QUIK CHEK™ negative | 3 | 714 |

		95% Confidence Limits
Predictive Negative Value	99.6%	98.7% - 99.9%
Correlation	96.9%	96.5% - 97.2%

Analytical Sensitivity

The test was consistently positive at a concentration of 0.4 ng/mL for GDH.

3

Cross-Reactivity

The specificity of the C. DIFF QUIK CHEK™ test was evaluated by examining the reactivity of a wide range of common intestinal bacteria and intestinal pathogens in the assay. For the analysis, the organisms were grown to early stationary phase (>10° CFU/ml). The I or the mary one, as comment in ids. The cultures were diluted in (i) fecal specimens that were negative for C. difficile (Negative Fecal Specimens) or (ii) fecal specimens that were spiked with toxigenic C. difficile cell filtrate to give a positive reaction (Positive Fecal Specimens). The latter specimens were evaluated to determine if any of the common intestinal bacteria and pathogens exhibited any deleterious effects on a positive reaction in the C. DIFF QUIK CHEK™ test. The fecal specimens then were diluted in Diluent and tested in the C. DIFF QUIK CHEK™ test.

| Bacterium | Strain | Reaction in
negative fecal
specimen | Reaction in
positive fecal
specimen |
|---------------------------------|------------|-------------------------------------------|-------------------------------------------|
| Aeromonas hydrophila | ATCC 7965 | - | + |
| Bacillus cereus | ATCC 14579 | - | + |
| Bacillus subtilis | ATCC 6051 | - | + |
| Bacteroides fragilis | VPI 13785 | - | + |
| Campylobacter coli | ATCC 49941 | - | + |
| Campylobacter fetus | ATCC 25936 | - | + |
| Campylobacter jejuni | ATCC 29428 | - | + |
| Candida albicans | ATCC 10231 | - | + |
| Clostridium bifermentans | VPI 2012 | - | + |
| Clostridium butyricum | VPI 8260 | - | + |
| Clostridium perfringens, type A | VPI 3624 | - | + |
| Clostridium septicum | VPI 1524 | - | + |
| Clostridium sordellii | VPI 9048 | - | + |
| Clostridium sordellii | VPI 7319 | - | + |
| Clostridium sporogenes | VPI 9743 | - | + |
| Enterococcus faecalis | ATCC 19433 | - | + |
| Escherichia coli EIEC | SD67 | - | + |
| Escherichia coli | ATCC 25922 | - | + |
| Escherichia coli O157 H7 | B1409 | - | + |
| Escherichia coli ETEC | E 2348169 | - | + |
| Klebsiella pneumoniae | ATCC 9997 | - | + |
| Peptostreptococcus anaerobius | ATCC 27337 | - | + |
| Proteus vulgaris | ATCC 6380 | - | + |

A summary of the results is shown in the tables on the following pages. All of the organisms tested were negative in the C. difficile-negative fecal specimens and had no effect on the reaction with C. difficile-positive fecal specimens.

4

| Bacterium | Strain | Reaction in
negative fecal
specimen | Reaction in
positive fecal
specimen |
|--------------------------------|------------|-------------------------------------------|-------------------------------------------|
| Salmonella typhimurium | ATCC 14029 | - | + |
| Shigella dysenteriae | ATCC 12022 | - | + |
| Shigella flexneri | ATCC 12122 | - | + |
| Shigella sonnei | ATCC 11060 | - | + |
| Staphylococcus aureus | ATCC 6358 | - | + |
| Staphylococcus aureus (Cowans) | ATCC 12598 | - | + |
| Staphylococcus epidermidis | VPI 13140 | - | + |
| Vibrio parahaemolyticus | ATCC 17802 | - | + |
| Yersinia enterocolitica | ATCC 9610 | - | + |

Culture fluids containing viruses were used as provided by the American Type Culture Collection. Each was diluted ca. 1:20 in the kit Diluent and tested according to the Package Insert. The titer of the fluids is shown in the table below.

| Virus | TCID50 units
(per 0.2 mL) | ATCC# | Reaction in
negative fecal | Reaction in
positive fecal |
|---------------------|------------------------------|---------|-------------------------------|-------------------------------|
| Adenovirus type 1 | 104.5 | VR-1 | - | + |
| Adenovirus type 2 | 106.5 | VR-846 | - | + |
| Adenovirus type 3 | 108.25 | VR-3 | - | + |
| Adenovirus type 5 | 106.75 | VR-5 | - | + |
| Adenovirus type 40 | 104.5 | VR-931 | - | + |
| Adenovirus type 41 | 104.5 | VR-930 | - | + |
| Human coronavirus | 103.5 | VR-740 | - | + |
| Coxsackievirus B2 | 105.75 | VR-29 | - | + |
| Coxsackievirus B3 | 105 | VR-30 | - | + |
| Coxsackievirus B4 | 104.75 | VR-184 | - | + |
| Coxsackievirus B5 | 107.5 | VR-185 | - | + |
| Echovirus 9 | 104.5 | VR-1050 | - | + |
| Echovirus 11 | 105 | VR-1052 | - | + |
| Echovirus 18 | 104 | VR-48 | - | + |
| Echovirus 22 | 103.3 | VR-1063 | - | + |
| Echovirus 33 | 105 | VR-582 | - | + |
| Enterovirus type 68 | 106 | VR-1076 | - | + |
| Enterovirus type 69 | 104.3 | VR-1077 | - | + |
| Enterovirus type 70 | 105.5 | VR-836 | - | + |
| Enterovirus type 71 | pending | VR-784 | - | + |

5

Interfering Substances

The following substances had no effect on test results, either with C. difficile-negative or C. difficile-positive fecal specimens, when present in fecal material in the concentrations indicated in the table.

| Substance | Concentration | Reaction in
negative fecal
specimen | Reaction in
positive fecal
specimen |
|-----------------------------------|---------------|-------------------------------------------|-------------------------------------------|
| Hog gastric mucin | 3.5% w/v | - | + |
| Human blood (O, Rh-) | 40% v/v | - | + |
| Barium sulfate | 5% w/v | - | + |
| Imodium® | 5% w/v | - | + |
| Kaopectate® | 5 mg/ml | - | + |
| Pepto-Bismol® | 5% w/v | - | + |
| Steric/palmitic acid (fecal fats) | 40% w/v | - | + |
| Metronidazole | 0.25% w/v | - | + |
| Vancomycin | 0.25% w/v | - | + |

Reproducibility

A total of 8 fecal specimens, 6 positive and 2 negative, were coded to prevent identification and were sent to each of three independent laboratories for analysis using the C. DIFF QUIK CHEK™ test. The results from each laboratory were compared with in-house results. The results were consistent among the different locations, and exhibited a correlation of 100%. The positive specimens were confirmed to be positive and the negative specimens were confirmed to be negative at all sites using the C. DIFF QUIK CHEKTM test.

6

8. REFERENCES

• 1. Bartlett JG. 1990. Clostridium difficile: clinical considerations. Rev. Infect. Dis. 12:S243-51
• 2. Bartlett JG. 1998. Clostridium difficile Associated diarrhea and colitis. In Infectious Diseases, 2nd Ed., (eds) Gorbach SL, Bartlett JG, and Blacklow NR, W.B. Saunders Company, Philadelphia, London, Toronto, Montreal, Sydney, Tokyo
• 3. Lyerly DM, Wilkins TD. 1995. Clostridium difficile. In Infections of the Gastrointestinal Tract (eds) Blaser MJ, Smith PD, Ravdin JI, Greenberg HB, and Guerrant RL Raven Press, Ltd., New York, pp 867-91
• 4. Lyerly DM, Neville LM, Evans DT, Fill J, Allen S, Greene W, Sautter R, Hnatuck P, Torpey D. Schwalbe R. 1998. Multicenter evaluation of the Clostridium difficile TOX A/B TEST. J. Clin. Microbiol. 36:184-90
• 5. Kato H, Kato N, Watanabe K, Iwai N, Nakamura H, Yamamoto T, Suzuki K, Kim S-M, Chong Y, Wasito EB. 1998. Identification of toxin A-negative, toxin B-positive Clostridium difficile by PCR. J. Clin. Microbiol. 36:2178-82
• 6. Alfa MJ, Kabani A, Lyerly D, Moncrief S, Neville LM, Al-Barrak A, Harding GK, Dyck B, Olekson K, Embil JM. 2000. Characterization of a toxin A-negative, toxin B-positive strain of Clostridium difficile responsible for a nosocomial outbreak of Clostridium difficileassociated diarrhea. J. Clin. Microbiol. 38:2706-14
• 7. Kraft D. 1999. Personal communications.
• 8. Kato H, Kato N, Katow S, Maegawa T, Nakamura S, Lyerly DM. 1999. Deletion in the repeating sequences of toxin A gene of toxin A-negative, toxin B-positive Clostridium difficile strains. FEMS Microbiol. Lett. 175:197-203
• 9. Moncrief JS, Zheng L, Neville LM, Lyerly DM. 2000. Genetic characterization of toxin Anegative, toxin B-positive Clostridium difficile isolates by PCR. J. Clin. Microbiol. 38:3072-5
• 10. von Eichel-Streiber C, Zec-Pirnat I, Grabnar M, Rupnik M. 1999. A nonsense mutation abrogates production of a functional enterotoxin A in Clostridium difficile toxinotype VIII strains of serogroups F and X. FEMS Microb. Lett. 178:163-8
• 11. Fluit AC, Wolfhagen MJHM, Verdonk GPHT, Jansze M, Torensma R, Verhoef J. 1991. Nontoxigenic strains of Clostridium difficile lack the genes for both toxin A and toxin B. J. Clin. Microbiol. 29:2666-7
• 12. Anderson BM, Anderson CD, Van Tassell RL, Lyerly DM, Wilkins TD. 1993. Purification and characterization of Clostridium difficile glutamate dehydrogenase. Archives Biochem. Biophy. 300:483-8
• 13. Lyerly DM, Barroso LA, Wilkins TD. 1991. Identification of the latex test-reactive protein of Clostridium difficile as glutamate dehydrogenase. J. Clin. Microbiol. 29:2639-42
• 14. Miles BL, Siders JA, Allen SD. 1988. Evaluation of a commercial latex test for Clostridium difficile for reactivity with C. difficile and cross-reactions with other bacteria. J. Clin. Microbiol. 26:2452-5
• 15. Lyerly DM, Ball DW, Toth J, Wilkins TD. 1988. Characterization of cross-reactive proteins detected by Culturette Brand Rapid Latex Test for Clostridium difficile. J. Clin. Microbiol. 26:397-400
• 16. Landry ML, Topal J, Ferguson D, Giudetti D, Tang Y. 2001. Evaluation of Biosite Triage Clostridium difficile panel for rapid detection of Clostridium difficile in stool samples. J. Clin. Microbiol 39:1855-8

7

• 17. Alfa MJ, Swan B, VanDekerkhove B, Pang P, Harding GK. 2002. The diagnosis of Clostridium difficile-associated diarrhea: comparison of Triage C. difficile panel, EIA for Tox A/B and cytotoxin assays. Diagn. Microbiol. Infect. Dis 43:257-63
• 18. Turgeon DK, Novicki TJ, Quick J, Carlson L, Miller P, Ulness B, Cent A, Ashley R, Larson A, Coyle M, Limaye AP, Cookson BT, Fritsche TR. 2003. Six Rapid Tests for Direct Detection of Clostridium difficile and Its Toxins in Fecal Samples Compared with the Fibroblast Cytotoxicity Assay. J. Clin. Microbiol. 41:667-70
• 19. Gumerlock PH, Tang YJ, Meyers FJ, Silva J, Jr. 1991. Use of the polymerase chain reaction for the specific and direct detection of Clostridium difficile in human feces. Rev. Infect. Dis. 13:1053- 60
• 20. Gumerlock PH, Tang YJ, Weiss JB, Silva J, Jr. 1993. Specific detection of toxigenic strains of Clostridium difficile in stool specimens. J. Clin. Microbiol. 31:507-11
• 21. Boondeekhun HS, Gurtler V, Odd ML, Wilson VA, Mayall BC. 1993. Detection of Clostridium difficile enterotoxin gene in clinical specimens by the polymerase chain reaction. J. Med. Microbiol. 38:385-7
• 22. Lou Q, Chong SKF, Fitzgerald JF, Siders JA, Allen SD, and Lee C-H. 1997. Rapid and effective method for preparation of fecal specimens for PCR assays. J. Clin. Microbiol. 35:281-3
• 23. Kato N, Ou C-Y, Kato H, Bartley SL, Luo C-C, Killgore G.E, and Ueno K. 1993. Detection of toxigenic Clostridium difficile in stool specimens by the polymerase chain reaction. J. Infect. Dis. 167:455-8
• 24. Rupnik M, Avesani V, Janc M, von Eichel-Streiber C, Delmee M. 1998. A novel toxinotyping scheme and correlation of toxinotypes with serogroups of Clostridium difficile isolates. J. Clin. Microbiol. 36:2240-7
• 25. Bélanger SD, Biossinot M, Clairoux N, Picard FJ, Bergeron MG. 2003. Rapid detection of Clostridium difficile in feces by real-time PCR. J. Clin. Microbiol. 41:730-4
• 26. Guilbault C, Labbe A-C, Poirier L, Busque L, Beliveau C Laverdiere M. 2002. Development and evaluation of a PCR method for detection of the Clostridium difficile toxin B gene in stool specimens. J. Clin. Microbiol. 40:2288-90
• 27. Wolfhagen MJHM, Fluit AC, Torensma R, Poppelier MJJG, Verhoef J. 1994. Rapid detection of toxigenic Clostridium difficile in fecal samples by magnetic immuno PCR assay. J. Clin. Microbiol. 32:1629-33
• 28. Summanen P, Baron EJ, Citron DM, Strong C, Wexler HM, Fingold SM, Wadsworth Anaerobic Bacteriology Manual, Fifth Edition. 1993. Star publishing company, Belmont, California
• 29. Zheng L, Keller SF, Lyerly DM, Carman RJ, Genheimer CW, Gleaves CA, Kohlhepp SJ, Young S, Perez S, Ye K (2004) Multicenter Evaluation of a New Screening Test that Detects Clostridium difficile in Fecal Specimens. J. Clin. Microbiol. 42:3837-3840

8

Image /page/8/Picture/1 description: The image shows the seal of the U.S. Department of Health & Human Services. The seal is circular and contains the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the top half of the circle. In the center of the seal is an abstract image of an eagle.

3 2006 NOV

Food and Drug Administration 2098 Gaither Road Rockville MD 20850

David M. Lyerly, Ph.D. Vice President of Research and Development TECHLAB®, Inc. 2001 Kraft Drive Blacksburg, VA 24060-6358

Re: K053572

Trade/Device Name: C. DIFF QUIK CHEK™ Regulation Number: 21 CFR 866.2660 Regulation Name: Microorganism Differentiation and Identification Device Regulatory Class: Class I Product Code: MCB Dated: March 29, 2006 Received: March 30, 2006

Dear Dr. Lyerly:

This letter corrects our substantially equivalent letter of April 26, 2006.

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 (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 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 Part 801); 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.

9

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 predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific information about the application of labeling requirements to your device, or questions on the promotion and advertising of your device, please contact the Office of In Vitro Diagnostic Device Evaluation and Safety at [phone]. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number [phone] or [phone] or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html.

Sincerely yours,

Sally, autogra

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

Enclosure

10

Indications for Use

510(k) Number (if known): K053572

C. DIFF QUIK CHEK TM Device Name:

Indications For Use: The C. DIFF QUIK CHEK™ test is a rapid membrane enzyme immunoassay for use as a screening test to detect Clostridium difficile antigen, glutamate dehydrogenase, in fecal specimens from persons suspected of having C. difficile disease. The test does not distinguish toxigenic from nontoxigenic strains of C. difficile. With the use of additional tests that detect C. difficile toxins, the test is to be used as an aid in the diagnosis of C. difficile disease. As with other C. difficile tests, 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)

Ludella T. Park

Page 1

vision Sien- M

Office of the Vitro Diagnosic Device Evaluation and Safer

K05 3572