← Product Code [LON](/submissions/MI/subpart-b%E2%80%94diagnostic-devices/LON) · K033907 # BD PHOENIX AUTOMATED MICROBIOLOGY SYSTEM - TRIMETHOPRIM-SULFAMETHOXAZOLE 0.5/9.5 - 16/304 UG/ML (K033907) _Becton, Dickinson & CO · LON · Apr 9, 2004 · Microbiology · SESE_ **Canonical URL:** https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/LON/K033907 ## Device Facts - **Applicant:** Becton, Dickinson & CO - **Product Code:** [LON](/submissions/MI/subpart-b%E2%80%94diagnostic-devices/LON.md) - **Decision Date:** Apr 9, 2004 - **Decision:** SESE - **Submission Type:** Traditional - **Regulation:** 21 CFR 866.1645 - **Device Class:** Class 2 - **Review Panel:** Microbiology ## Intended Use The BD Phoenix™ Automated Microbiology System is intended for the rapid identification and in vitro antimicrobial susceptibility testing of isolates from pure culture of most aerobic and facultative anaerobic Gram-negative and Gram-positive bacteria of human origin. ## Device Story System performs automated identification and antimicrobial susceptibility testing (AST) of bacterial isolates. Input: pure culture bacterial isolates inoculated into Phoenix ID/AST broth. Process: broth microdilution method using sealed polystyrene panels with 136 micro-wells containing dried reagents; continuous incubation at 35°C; automated optical readings every 20 minutes measuring redox indicator changes and bacterial turbidity. Output: MIC values and categorical interpretations (S, I, R, N). Used in clinical microbiology laboratories by trained personnel. Results assist clinicians in selecting appropriate antimicrobial therapy for patients with bacterial infections. ## Clinical Evidence Performance evaluated using clinical, stock, and challenge isolates. Study compared Phoenix System results to NCCLS reference broth microdilution method. Results for trimethoprim-sulfamethoxazole (n=634) showed 96.4% Essential Agreement and 97.9% Category Agreement. Reproducibility testing at three sites demonstrated >90% intra-site and >95% inter-site reproducibility for Gram-positive isolates. ## Technological Characteristics Automated microbiology system; polystyrene trays with 136 micro-wells; redox indicator (colorimetric oxidation-reduction) for growth detection; broth microdilution method; 35°C incubation; automated optical reading every 20 minutes; software-based 'EXPERT' rule system for interpretation; connectivity via barcode scanning. ## Regulatory Identification A fully automated short-term incubation cycle antimicrobial susceptibility system is a device that incorporates concentrations of antimicrobial agents into a system for the purpose of determining in vitro susceptibility of bacterial pathogens isolated from clinical specimens. Test results obtained from short-term (less than 16 hours) incubation are used to determine the antimicrobial agent of choice to treat bacterial diseases. ## Special Controls *Classification.* Class II (special controls). The special control for this device is FDA's guidance document entitled “Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA.” ## Predicate Devices - VITEK® System (PMA No. N50510) - BD Phoenix™ Automated Microbiology System with Gatifloxacin ([K020321](/device/K020321.md)) - BD Phoenix™ Automated Microbiology System with Ofloxacin ([K020323](/device/K020323.md)) - BD Phoenix™ Automated Microbiology System with Levofloxacin ([K020322](/device/K020322.md)) ## Submission Summary (Full Text) > This content was OCRed from public FDA records by [Innolitics](https://innolitics.com). If you use, quote, summarize, crawl, or train on this content, cite Innolitics at https://innolitics.com. > > Innolitics is a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices, including [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/). {0} 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY DEVICE ONLY TEMPLATE A. 510(k) Number: k033907 B. Purpose of Submission: Addition of the trimethoprim - sulfamethoxazole to the BD Phoenix™ Automated Microbiology System C. Analyte: Trimethoprim - sulfamethoxazole 0.5/9.5 – 16/304 µg/mL Gram-Positive AST D. Type of Test: Antimicrobial Susceptibility Test (Quantitative) colorimetric oxidation-reduction, growth-based E. Applicant: Becton, Dickinson & Company F. Proprietary and Established Names: BD Phoenix™ Automated Microbiology System – Trimethoprim - sulfamethoxazole Gram Positive Panel G. Regulatory Information: 1. Regulation section: 21 CFR 866.1645 Fully Automated Short-Term Incubation Cycle Antimicrobial Susceptibility System 2. Classification: Class II 3. Product Code: LON 4. Panel: 83 H. Intended Use: 1. Intended use(s): BD Phoenix™ Automated Microbiology System: The BD Phoenix™ Automated Microbiology System is intended for the in vitro quantitative determination of antimicrobial susceptibility by minimal inhibitory concentration of gram-negative aerobic and facultative anaerobic bacteria belonging to the family Enterobacteriaceae and non-Enterobacteriaceae and gram-positive bacteria belonging to the genera Staphylococcus and Enterococcus. The BD Phoenix™ GP Panel: The BD Phoenix™ Automated Microbiology System is intended for the in vitro rapid identification (ID) and quantitative determination of antimicrobial susceptibility by minimal inhibitory concentration (MIC) of gram-positive {1} Page 2 of 5 bacteria from pure culture belonging to the genera Staphylococcus and Enterococcus. 2. Indication(s) for use: This submission is for the addition of the antibiotic trimethoprim - sulfamethoxazole at concentrations of 0.5/9.5 – 16/304 to the gram positive susceptibility panel. 3. Special condition for use statement(s): S. aureus only Prescription use only 4. Special instrument Requirements: Not applicable I. Device Description: The BD Phoenix™ Automated Microbiology System includes instrumentation and software, sealed and self-inoculating molded polystyrene trays with 136 micro-wells containing dried reagents, and specific inoculum broth formulations for ID and AST Indicator. The organism to be tested must be a pure culture and be preliminarily identified as gram positive or gram negative. Colonies are then suspended in broth, and equated to a 0.5 McFarland with the recommendation to use the BD CrystalSpec™ Nephelometer. A further dilution is made into an AST broth, which contains an AST indicator, prior to inoculating the panel. The AST broth is a cation-adjusted formulation of Mueller-Hinton broth containing 0.01% Tween 80. After adding the indicator solution to the AST inoculum the color is blue and after inoculation and incubation goes to pink to colorless as reduction in the panel well proceeds. Inoculated panels are barcode scanned and loaded into the BD Phoenix™ Automated Microbiology System instrument where the panels are continuously incubated at 35°C. The AST has a final inoculum of 5 × 10⁵ CFU/ml. The instrument incubates, reads and records the results of the biochemical substrates and antimicrobial agents and interprets the reactions to give an ID of the isolate and MIC value and category interpretation of the antimicrobial agents. Organisms growing in the presence of a given antimicrobic agent reduce the indicator, signaling organism growth and resistance to the antimicrobic agent. Organisms killed or inhibited by a given antimicrobic do not cause reduction of the indicator and therefore do not produce a color change. Additional interpretation is done using software driven "EXPERT" System using rules derived from the NCCLS standards. Readings are taken every 20 minutes with an ID result available between 2-12 hours and an AST result available between 4-16 hours. This is only an autoread result; there are no manual readings possible. {2} Page 3 of 5 # J. Substantial Equivalence Information: 1. Predicate device name(s): VITEK® System 2. Predicate K number(s): N50510 3. Comparison with predicate: | Similarities | | | | --- | --- | --- | | Item | Device | Predicate | | 1. | Isolated colonies from culture used | Isolated colonies from culture used | | 2. | Report results as minimum inhibitory concentration (MIC) and categorical interpretation (SIR) | Report results as minimum inhibitory concentration (MIC) and categorical interpretation (SIR) | | 3. | <16 hours | <16 hours | | Differences | | | | Item | Device | Predicate | | 1. | Results are determined from serial twofold dilutions of antimicrobial agents | Results are determined from extrapolation of doubling dilutions | | 2. | Inoculum density equated to 0.5 McFarland standard | Inoculum density equated to 1.0 McFarland standard | | 3. | Automated growth based enhanced by use of a redox indicator (colorimetric oxidation-reduction) to detect organism growth. | Automated growth based with detection using an attenuation of light measured by an optical scanner. | # K. Standard/Guidance Document Referenced (if applicable): "Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA"; NCCLS M7 (M100-S14) "Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically; Approved Standard." # L. Test Principle: The system employs conventional, colorimetric, fluorogenic and chromogenic substrates to identify the genus and species of the isolate. The AST portion of the BD Phoenix™ Automated Microbiology System is a broth based microdilution method that utilizes a redox indicator (colorimetric oxidation-reduction) to enhance detection of organism growth. The MIC is determined by comparing growth in wells containing serial two-fold dilutions of an antibiotic to the growth in "growth control wells" which contain no antibiotic. # M. Performance Characteristics (if/when applicable): 1. Analytical performance: {3} Page 4 of 5 a. Precision/Reproducibility: Nine isolates were evaluated for site to site and inter site reproducibility demonstrating >95% reproducibility. The ten isolate study described in the guidance document was used (10 organisms tested 3 times on 3 days at 3 sites). b. Linearity/assay reportable range: Not applicable c. Traceability (controls, calibrators, or method): The recommended QC isolate was tested a sufficient number of times with acceptable results with the reference method. The Phoenix results demonstrate that the system can produce QC results in the recommended range. An alternate organism was selected by BD to run on the reference panel to assure that they were performing as expected since all recommended QC isolates are off scale. | ORGANISM | conc. | Reference | | Phoenix | | | --- | --- | --- | --- | --- | --- | | | | | | | | | E. faecalis ATCC 29212 Expected Range: ≤0.5 μg/mL | ≤0.5 | 140 | | 136 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | S. aureus ATCC 29213 Expected Range: ≤0.5 μg/mL | ≤0.5 | 140 | | 139 | | | | | | | | | | | | | | | | | | | | | | | Inoculum density control: The organism suspension density of the ID broth was equivalent to a 0.5 McFarland standard using the BBL™ CrystalSpec™ Nephelometer which was verified each day of testing. Internal data was used to demonstrate that the use of the BBL™ CrystalSpec™ Nephelometer would produce reproducible results. Five different instruments were used. d. Detection limit: Not applicable e. Analytical specificity: Not applicable f. Assay cut-off: Not applicable {4} Page 5 of 5 2. Comparison studies: a. Method comparison with predicate device: The NCCLS recommended broth dilution reference panel was prepared according to the NCCLS standards. Clinical testing was performed at four sites. The testing included both fresh clinical isolates and stock isolates along with a challenge set with known results. Isolates were all S. aureus. The test device had a growth rate of 99.7%. A comparison was provided to the reference method with the following agreement. | | EA Tot | EA N | EA % | Eval EA Tot | Eval EA N | Eval EA % | CA N | CA % | #R | min | maj | vmj | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | Clinical | 604 | 582 | 96.4 | 20 | 2 | 10.0 | 591 | 97.8 | 23 | N/A | 11 | 2 | | Challenge | 30 | 29 | 96.7 | 0 | 0 | 0 | 30 | 100.0 | 0 | N/A | 0 | 0 | | Combined | 634 | 611 | 96.4 | 20 | 2 | 10.0 | 621 | 97.9 | 23 | N/A | 11 | 2 | EA-Essential Agreement CA-Category Agreement R-resistant isolates maj-major discrepancies vmj-very major discrepancies min- minor discrepancies NA – No intermediate range therefore no minor errors possible Essential agreement (EA) is when the BD Phoenix™ panels agree with the reference test panel results exactly or within one doubling dilution of the reference method. Category agreement (CA) is when the BD Phoenix™ panel result interpretation agrees exactly with the reference panel result interpretation. b. Matrix comparison: Not applicable 3. Clinical studies: a. Clinical sensitivity: Not applicable b. Clinical specificity: Not applicable c. Other clinical supportive data (when a and b are not applicable): Not applicable 4. Clinical cut-off: Not applicable 5. Expected values/Reference range: ≤2/38 (S), ≥4/76(R) The expected value range, interpretative criteria and QC are the same as recommended by NCCLS. All values will be included in the package insert. N. Conclusion: The submitted information in this premarket notification is complete and supports a substantial equivalence decision. --- **Source:** [https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/LON/K033907](https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/LON/K033907) **Published by [Innolitics](https://innolitics.com)** — a medical-device software consultancy. We help companies design, build, and clear FDA-regulated software and AI/ML devices. If you're preparing [a 510(k)](https://innolitics.com/services/510ks/), [a De Novo](https://innolitics.com/services/regulatory/), [a SaMD](https://innolitics.com/services/end-to-end-samd/), [an AI/ML medical device](https://innolitics.com/services/medical-imaging-ai-development/), or [an FDA regulatory strategy](https://innolitics.com/services/regulatory/), [get in touch](https://innolitics.com/contact). **Cite:** Innolitics at https://innolitics.com