A. The qualitative detection of nasal colonization of methicillin-resistant Staphylococcus aureus (MRSA), to aid in the prevention and control of MRSA in healthcare settings.

The test is performed on anterior nares swab specimens from patients and healthcare workers to screen for MRSA colonization. chromID™MRSA when used to detect nasal colonization is not intended to diagnose, guide, or monitor therapy for MRSA infections, or provide results of susceptibility to methicillin.

B. The qualitative detection of MRSA from skin structure infections.

chromID™ MRSA is indicated for use in conjunction with other laboratory tests and clinical data available to aid in the identification and diagnosis of MRSA infections. Concomitant cultures for skin structure infections are necessary to recover organisms for further microbiological susceptibility testing or epidemiological typing.

A negative result does not preclude MRSA infection. chromID™MRSA is not intended to monitor treatment for MRSA · infections, or provide results of susceptibility to methicillin.

Device Description

chromID™ MRSA agar consists of a rich nutritive base combining different peptones. It also contains a chromogenic substrate of α-glucosidase and a combination of several antibiotics (cefoxitin, etc.) that favor the growth and direct detection of MRSA, including hetero-resistant strains, by revealing orglucosidase activity (patent registered) through the appearance of green colonies. The α-glucosidase produced by S. aureus cleaves the chromogenic substrate, which gives a green color to the S. aureus colonies growing on the medium. The MRSA strains are identified by the presence of green colonies that result from the chromogen incorporated in the medium. The selective mixture of antibiotics inhibits most bacteria not belonging to the genus Staphylococcus, as well as yeasts.

AI/ML Overview

Here's an analysis of the acceptance criteria and study findings for the chromID™ MRSA device, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state pre-defined acceptance criteria for the clinical study's sensitivity and specificity. However, the reported performance metrics can be considered the demonstrated performance of the device.

Performance Metric	Acceptance Criteria (Implied)	Reported Device Performance
Preamble/General Acceptability	Adequate analytical and clinical performance to be substantially equivalent to the predicate device and aid in MRSA detection.	Demonstrated substantial equivalence to predicate device based on analytical and clinical studies.
Reproducibility	100% reproducibility rate for mecA-positive/negative S. aureus isolates over 5 days across 3 sites.	100% (450/450)
Quality Control	≥95% agreement with expected results for QC organisms (ATCC 29213, ATCC 43300) when compared to oxacillin MIC and mecA PCR.	Met pre-defined acceptance criteria.
Analytical Reactivity (mecA MRSA)	N/A (Challenge set of 80 mecA-MRSA)	58/80 (72.5%) detected
Analytical Reactivity (mecC MRSA)	N/A (Challenge set of 5 mecC-MRSA)	4/5 (80%) detected
Expression of Resistance (Low & High-level MRSA)	All low and high-level methicillin-resistant S. aureus strains detected at >10² CFU/mL.	All detected at an inoculum of >10² CFU/mL.
Expression of Resistance (Borderline Oxacillin-Resistant & Methicillin-Susceptible S. aureus)	No growth at high inoculum concentrations.	No growth at inoculum concentrations as high as 10⁸ CFU/mL.
Mixed Infection Study	Performance not negatively impacted by presence of non-MRSA organisms.	Presence of non-MRSA organisms did not negatively impact chromID™ MRSA performance.
Recovery Study (ATCC® 43300™)	N/A (Lowest detection limit)	10³ CFU/mL at 24 hours
Recovery Study (CDC Mu3-8R)	N/A (Lowest detection limit)	10² CFU/mL at 24 hours
Cross Reactivity (Non-MRSA strains)	N/A (Expected limited cross-reactivity for specific non-MRSA strains, and green colonies for specific resistance mechanisms)	44 strains did not grow. 20 strains grew without green pigment. 3 Klebsiella pneumoniae (KPC), 1 Enterobacter cloacae (KPC), 1 S. pseudintermedius (oxacillin-resistant), 2 S. sciuri (oxacillin-resistant) showed green colonies.
Interference	No interference from physiologically/biologically relevant concentrations of common substances; acknowledges potential inhibition from certain topical antibiotics/antiseptics.	No interference from human blood, mucin, anticoagulants, plasma, buffy coat. Specific topical antibiotics/antiseptics listed as inhibitory.
Incubation Time (ATCC 43300, S. aureus 0611169)	N/A (Time to positive)	20 hours
Incubation Time (CDC Mu3-8R)	N/A (Time to positive)	27 hours
Clinical Study Sensitivity	Not explicitly stated, but high sensitivity would be expected for a screening/diagnostic aid.	93.8% (95% CI: [89.2-96.5])
Clinical Study Specificity	Not explicitly stated, but high specificity would be expected for a screening/diagnostic aid.	97.4% (95% CI: [95.6-98.5])

Note: The document does not explicitly state numerical "acceptance criteria" for sensitivity and specificity. The reported values are the observed performance. The FDA's substantial equivalence determination implies these values were deemed acceptable.

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

Test Set Sample Size: 680 specimens (valid for comparison after exclusions)
Data Provenance: Clinical study data from four geographically diverse clinical sites. This suggests prospective collection within the United States, given it's an FDA submission. The specific country is not explicitly stated beyond "geographically diverse clinical sites" in relation to the US FDA. The nature of the study (collection of specimens for device evaluation) indicates it's prospective.

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

The document does not specify the "number of experts" or their "qualifications" involved in establishing the ground truth. Ground truth was established using standard microbiological laboratory methods (Reference Culture Method) which would be performed by trained laboratory personnel.

4. Adjudication Method for the Test Set

The document describes a clear reference method for ground truth determination, which inherently serves as the "adjudication" (or gold standard). It does not mention a separate, independent adjudication panel or specific method like "2+1" or "3+1" for resolving discrepancies between the new device and the reference method. Discordant results were analyzed and described.

Reference Culture Method:
- Specimens enriched in Tryptic Soy broth with 6.5% NaCl (TSB) for 24 hours (negative broths incubated an additional 24 hours).
- Positive broth cultures subcultured to Tryptic Soy agar with 5% sheep blood (BAP).
- Colonies suggestive of Staphylococcus species tested by Gram stain, catalase, and latex agglutination.
- Staphylococcus aureus isolates tested for resistance to oxacillin by the Cefoxitin Screen test (30µg).
- All oxacillin-resistant colonies by Cefoxitin Screen test were tested for the presence of the mecA gene by PCR and by VITEK® MS for species confirmation.
Definition of Positive Ground Truth: Recovery of cefoxitin-resistant Staphylococcus aureus from the specimen.
Definition of Negative Ground Truth: All other results (growth of cefoxitin-susceptible Staphylococcus aureus, growth of other species, or no growth).

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This device is a culture medium, and its performance is assessed by direct comparison to a laboratory reference method, not by comparing human reader interpretations with and without AI assistance.

6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done

This is a standalone microbiological culture medium. Its performance (presence/absence of green colonies indicating MRSA) is interpreted directly by laboratory personnel based on the visual result of the culture. There is no separate "algorithm" being evaluated beyond the efficacy of the chromogenic medium itself. The clinical study evaluates this standalone culture medium's ability to detect MRSA compared to a reference lab method.

7. The Type of Ground Truth Used

The ground truth used was a composite reference standard based on:

Standard microbiological culture methods (TSB enrichment, BAP subculture)
Phenotypic tests (Gram stain, catalase, latex agglutination, Cefoxitin Screen test for oxacillin resistance)
Molecular confirmation (mecA gene PCR)
Species confirmation (VITEK® MS)

This detailed approach combines multiple laboratory techniques to confirm the presence and methicillin-resistance of Staphylococcus aureus.

8. The Sample Size for the Training Set

The document does not mention a "training set" in the context of an algorithm or machine learning. As a diagnostic culture medium, it would have been developed and optimized through in vitro studies and experiments, but the concept of a "training set" for an algorithm's development, distinct from analytical validation, is not applicable here. The analytical performance data (e.g., reactivity, reproducibility, cross-reactivity) serves to demonstrate the medium's inherent characteristics.

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

Not applicable, as there is no "training set" for an algorithm in the traditional sense. The ground truth for the analytical studies (e.g., for determining mecA status for reactivity studies) would have been established using established molecular and phenotypic methods, similar to those used for the clinical ground truth. For instance, the QC organisms were compared to oxacillin MIC and mecA PCR.

Summary

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Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002

March 11, 2016

BIOMERIEUX, INC. JEWELL COULSON SR. REGULATORY AFFAIRS SPECIALIST 595 ANGLUM RD. HAZELWOOD MO 63042

Re: K151688

Trade/Device Name: chromID™ MRSA Regulation Number: 21 CFR 866.1700 Regulation Name: Culture medium for antimicrobial susceptibility tests Regulatory Class: II Product Code: JSO Dated: February 4, 2016 Received: February 8, 2016

Dear Ms. Coulson:

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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

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 Parts 801 and 809); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); 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.

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If you desire specific advice for your device on our labeling regulations (21 CFR Parts 801 and 809), please contact the Division of Industry and Consumer Education at its toll-free number (800) 638 2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm. 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 Industry and Consumer Education at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely yours,

Ribhi Shawar -S

For Uwe Scherf, 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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DEPARTMENT OF HEALTH AND HUMAN SERVIGES Food and Drug Administration

Indications for Use

510(k) Number (if known) K151688

Device Name

chromIDTM MRSA

Indications for Use (Describe)

chromID™ MRSA agar is a selective and differential chromogenic medium for :

A. The qualitative detection of nasal colonization of methicillin-resistant Staphylococcus aureus (MRSA), to aid in the prevention and control of MRSA in healthcare settings.

B. The qualitative detection of MRSA from skin structure infections.

A negative result does not preclude MRSA infection. chromID™MRSA is not intended to monitor treatment for MRSA · infections, or provide results of susceptibility to methicillin.

Type of Use (Select one or both, as applicable)
-------------------------------------------------

Prescription Use (Part 21 CFR 801 Subpart D)

Over-The-Counter Use (21 CFR 801 Subpart C)

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510(k) SUMMARY

Submitter's Name:	bioMérieux, Inc.
Address:	595 Anglum RoadHazelwood, MO 63042
Contact Person:	Jewell CoulsonSenior Regulatory Affairs Specialist
Phone Number:	314-731-7342
Fax Number:	314-731-8689
Date of Preparation:	February 4, 2016
Device :
Formal/Trade Name:	chromID™ MRSA
Common Name:	Culture media
Classification	II
Regulation Name	Culture Media for Antimicrobial Susceptibility Tests
Regulation Number	21 CFR 866.1700
Product Code	JSO
Predicate Device:	Bio-Rad MRSA Select™ (K100589)
510(k) Summary:

Intended Use:

chromID™ MRSA agar is a selective and differential chromogenic medium for :

A. The qualitative detection of nasal colonization of methicillin-resistant Staphylococcus aureus (MRSA), to aid in the prevention and control of MRSA in healthcare settings.
The test is performed on anterior nares swab specimens from patients and healthcare workers to screen for MRSA colonization. chromID™ MRSA when used to detect nasal colonization is not intended to diagnose, guide, or monitor therapy for MRSA infections, or provide results of susceptibility to methicillin.
B. The qualitative detection of MRSA from skin structure infections.
chromID™ MRSA is indicated for use in conjunction with other laboratory tests and clinical data available to aid in the identification and diagnosis of MRSA infections. Concomitant cultures for skin and skin structure infections are necessary to recover organisms for further microbiological susceptibility testing or epidemiological typing. A negative result does not preclude MRSA infection. chromID™ MRSA is not intended to monitor treatment for MRSA infections, or provide results of susceptibility to methicillin.

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Device Description:

Substantial Equivalence

The similarities of ChromID™ MRSA agar when compared to the predicate device are described in the following table.

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	Device	Predicate
Item	chromID™ MRSA Agar	Bio-Rad MRSASelect™
Similarities
Intended Use	chromID™ MRSA agar is a selective anddifferential chromogenic medium for :	MRSASelect™ is a selective anddifferential chromogenic medium for:
	A. The qualitative detection of nasal colonizationof methicillin-resistant Staphylococcusaureus (MRSA), to aid in the prevention andcontrol of MRSA in healthcare settings.The test is performed on anterior nares swabspecimens from patients and healthcareworkers to screen for MRSA colonization.chromID™ MRSA when used to detect nasalcolonization is not intended to diagnose,guide, or monitor therapy for MRSAinfections, or provide results of susceptibilityto methicillin.	A) The qualitative detection of nasalcolonization of methicillin resistantStaphylococcus aureus (MRSA) to aidin the prevention and control of MRSAinfections in healthcare settings. Thetest can be performed on anteriornares specimens from patients andhealthcare workers to screen forMRSA colonization. MRSASelect™ isnot intended to diagnose MRSAinfection nor to guide or monitortreatment of infection. Results can beinterpreted after 18 to 28 hoursincubation.
	B. The qualitative detection of MRSA from skinand skin structure infections.chromID™ MRSA is indicated for use inconjunction with other laboratory tests andclinical data available to aid in theidentification and diagnosis of MRSAinfections. Concomitant cultures for skin andskin structure infections are necessary torecover organisms for further microbiologicalsusceptibility testing, or epidemiologicaltyping.A negative result does not preclude MRSAinfection. chromID™ MRSA is not intended tomonitor treatment for MRSA infections, orprovide results of susceptibility to methicillin.	B) The qualitative detection of methicillinresistant Staphylococcus aureus(MRSA) from skin and soft-tissuewound specimens. TheMRSASelect™ is indicated for use inconjunction with other laboratory testsand clinical data available to aid in theidentification and diagnosis of MRSAfrom patients with skin and soft-tissueinfections. Concomitant cultures andsusceptibility testing are necessary forall skin and soft-tissue woundspecimens. MRSASelect™ is notintended to guide, or monitor treatmentfor MRSA infection, or provides resultsof susceptibility to methicillin. Resultscan be interpreted after 18 to 28 hoursincubation.
Test method	Manual	Manual
Inoculum	Direct Specimen	Direct Specimen
Specimen	Anterior nares specimens	Anterior nares specimens
	Skin and skin structure specimens	Skin and soft-tissue wound specimens

The chromID™ MRSA agar utilizes nutrient agar medium that contains selective and differential agents and is very similar to the MRSASelect™ agar. Both devices incorporate a chromogenic substrate that is enzymatically cleaved by S. aureus and result in colored MRSA colonies. Both devices incorporate selective agents in the agar to inhibit most bacteria not belonging to the genus Staphylococcus, as well as yeasts. The significant technological difference between the two media is the type of chromogenic substrate incorporated in the media to indicate the presence of MRSA colonies. The safety and effectiveness of the chromID™ MRSA agar is not impacted by the technology differences.

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Performance Characteristics:

Non-clinical (analytical) and clinical studies were performed for the chromID™ MRSA agar following the FDA Draft Guidance "Establishing the Performance Characteristics of In Vitro Diagnostic Devices for the Detection of Methicillin-Resistant Staphylococcus aureus (MRSA) for Culture Based Systems", issued June 15, 2011.

Analytical Performance

Reproducibility A set of ten mecA-positive or mecA-negative Staphylococcus aureus isolates . were tested in triplicate each day for five days at three of the clinical study sites using multiple lots of chromID™ MRSA media. Isolates were tested at 103 CFU/mL and plates were read at 24 hours. The overall reproducibility rate was 100% (450/450).
Quality Control Two quality control organisms were tested at each study site by chromlD™ ● MRSA on each day of testing. The organisms tested were:

Staphylococcus aureus	ATCC 29213
Staphylococcus aureus	ATCC 43300

The results of QC testing with chromID™ MRSA agar met the pre-defined acceptance criteria (≥ 95% agreement) when compared to expected results as determined by oxacillin MIC and mecA PCR.

Analytical Reactivity - A challenge set composed of 80 mecA MRSA strains and 5 mecC MRSA strains was inoculated on the chromID™ MRSA medium with an inoculum equivalent to 10° CFU/mL. After 24 hours of incubation, 58/80 mecA MRSA strains and 4/5 mecC MRSA strains were detected on the chromID™ MRSA medium.
. Expression of Resistance - Twenty-eight well-characterized S. aureus strains were tested on chromID™ MRSA (10 low level methicillin-resistant, 10 high level methicillin-resistant, 5 borderline oxacillin-resistant, and 3 methicillin-susceptible) using inoculum concentrations between 100 -10° CFU/mL. All low level and high level methicillin-resistant strains were detected at an inoculum of >10° CFU/mL. The 5 border-line oxacillin-resistant and 3 methicillin-susceptible strains did not grow, as expected, on chromID™ MRSA at inoculum concentrations as high as 10° CFU/mL.
Mixed Infection Study Ten MRSA strains (5 low level methicillin-resistant and 5 high level ● methicillin-resistant) at a concentration of 103 CFU/mL were inoculated on chromID™ MRSA with one of three non-MRSA strains (methicillin-susceptible S. aureus, methicillin-resistant coaqulase negative Staphylococcus epidermidis, and Escherichia coli) at 10° – 10° CFU/mL to evaluate the recovery of MRSA on chromID™ MRSA media in the presence of non-target organisms. The presence of these non-MRSA organisms did not negatively impact chromID™ MRSA performance.

Recovery Study .

Two well-characterized MRSA strains (ATCC® 43300™ and CDC Mu3-BR) were tested to determine the lowest number of CFU/mL detected on chromID™ MRSA. At 24 hours the lowest dilution for detection on chromID™ MRSA for ATCC® 43300™ was 103 CFU/mL and 10° CFU/mL for CDC Mu3-8R.

Cross Reactivity To evaluate the analytical specificity of the chromID™ MRSA media, 71 non-● MRSA strains representing bacterial and fungal species potentially encountered in skin and skin structure infections were inoculated onto chromID™ MRSA medium at a high inoculum level (10° CFU/mL). After 24 hours of incubation, 44 strains did not grow and 20 strains grew colonies without green pigment. Green colonies (cross reactivity) were observed for 3 Klebsiella

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pneumoniae and one Enterobacter cloacae strains. All 4 were carbapenemase producing (KPC). Green colonies were also observed for one S. pseudintermedius and 2 S. sciuri strains. All 3 were oxacillin-resistant strains.

Interference Interfering substances were evaluated at physiologically or biologically relevant ● concentrations and mixed with bacterial suspensions (9:1, v:v). No interference was observed for human blood, mucin, anticoagulants, plasma, and buffy coat. Some topical antibiotics and antiseptics interfered with MRSA detection on chromID™ MRSA due to their antibacterial activity. Use of compounds containing the active ingredients listed below may have an inhibitory effect on MRSA growth that is unrelated to chromID™ MRSA medium performance: colistimethate sodium 25 MUI/100mL, bacitracin 50,000 Ul/100mL, dexamethasone 0.1g/100mL, neomycin sulfate 350,000 Ul/100mL, polymixin B sulfate 600,000 Ul/100mL, benzalkonium chloride 500mg/100mL, chlorhexidine digluconate 200mg/100mL, 1% hydrocortisone, 10% povidone iodine, 2% mupirocin, hydrogen peroxide 8 mg/g, ethanol 380 mg/g, 70% isopropyl alcohol. Benzocaine (14 g/L) may delay colony coloration or inhibit growth of MRSA on chromID™ MRSA.
Incubation The incubation times required for three MRSA strains, at an organism concentration ● of 103 CFU/mL to produce positive chromID™ MRSA results was 20 hours for two strains (ATCC 43300 and S. aureus 0611169) and 27 hours for one strain (CDC Mu3-8R).

Clinical Studies

chromID™ MRSA was evaluated at four geographically diverse clinical sites. chromID™ MRSA performance was determined by examining the presence of green colonies on the media after 24 hours. All green colonies were tested by Gram stain, catalase and latex agglutination. All Staphylococcus aureus colonies were tested for resistance to oxacillin by the Cefoxitin Screen test (30ug). All green colonies were also tested for the presence of the mecA gene by PCR and by VITEK® MS for species confirmation.

For the Reference Culture Method, all specimens were enriched in Tryptic Soy broth with 6.5% NaCl (TSB) for 24 hours. Negative broth cultures were incubated an additional 24 hours. Positive cultures were then subcultured to Tryptic Soy agar with 5% sheep blood (BAP). Colonies suggestive of Staphylococcus species were tested by Gram stain, catalase and latex aqqlutination. Staphylococcus aureus isolates were tested for resistance to oxacillin by the Cefoxitin Screen test. All colonies resistant to oxacillin by the Cefoxitin Screen test were tested for the presence of the mecA gene by PCR and by VITEK MS for species confirmation.

A positive result by Reference Culture was defined as the recovery of cefoxitin-resistant Staphylococcus aureus from the specimen. All other results, including the growth of cefoxitinsusceptible Staphylococcus aureus, growth of other species and no growth, were considered negative.

A total of 690 SSSI specimens were collected for the study at 4 external clinical laboratories. Three specimens were excluded because they did not meet specimen acceptance criteria. Seven specimens were removed due to protocol deviations. A total of 680 specimens were valid for comparison data analysis.

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chromID™ MRSA at 24 Hours

Compared to Reference Culture Method (TSB) at 48 Hours

	Reference Culture Method(TSB) Result
chromID™ MRSAResult in 24h	Pos	Neg	Total
Pos	166	13*	179
Neg	11**	490	501
Total	177	503	680

*13 discordant specimens (chromID™ MRSA result of MRSA positive: culture-based testing result of MRSA neqative) were observed. 5 of the 13 chromID™ MRSA positive specimens were confirmed as MRSA by Cefoxitin Screen Test. 8 cultures grew green colonies on
chromID™MRSA that were not MRSA.

**11 discordant specimens (chromID™ MRSA result of MRSA negative: culture-based testing result of MRSA positive) were observed. 6 cultures displayed no growth on chromID' MRSA. 4 cultures grew non-green MRSA colonies on chromID™ MRSA. One specimen grew green colonies on chromID™ MRSA that were not identified as MRSA.

Specificity 97.4% (95% CI: [95.6-98.5]) Sensitivity 93.8% (95% CI: [89.2-96.5])

The overall prevalence of MRSA in this study by the Reference Culture Method was 26.0% (177/680). . The prevalence of MRSA as determined by chromID™ MRSA at 24 hours was 26.3% (179/680).

Conclusion

A comparison of the intended use and the results of non-clinical performance studies support that chromID™ MRSA agar is substantially equivalent to the predicate device.

Regulation Number and Section

§ 866.1700 Culture medium for antimicrobial susceptibility tests.

(a)
Identification. A culture medium for antimicrobial susceptibility tests is a device intended for medical purposes that consists of any medium capable of supporting the growth of many of the bacterial pathogens that are subject to antimicrobial susceptibility tests. The medium should be free of components known to be antagonistic to the common agents for which susceptibility tests are performed in the treatment of disease.(b)
Classification. Class II (performance standards).