← Product Code [LTT](/submissions/MI/subpart-b%E2%80%94diagnostic-devices/LTT) · K062777 # MICROSCAN MICROSTREP PLUS PANEL, CLINDAMYCIN (K062777) _Dade Behring, Inc. · LTT · Oct 10, 2006 · Microbiology · SESE_ **Canonical URL:** https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/LTT/K062777 ## Device Facts - **Applicant:** Dade Behring, Inc. - **Product Code:** [LTT](/submissions/MI/subpart-b%E2%80%94diagnostic-devices/LTT.md) - **Decision Date:** Oct 10, 2006 - **Decision:** SESE - **Submission Type:** Traditional - **Regulation:** 21 CFR 866.1640 - **Device Class:** Class 2 - **Review Panel:** Microbiology ## Intended Use To determine bacterial antimicrobial agent susceptibility The MicroScan MICroSTREP plus® Panel is used to determine quantitative and/or qualitative antimicrobial agent susceptibility of colonies grown on solid media of aerobic streptococci, including Streptococcus pneumoniae. After inoculation, panels are incubated for 20 - 24 hours at 35°C +/- 1°C in a non-CO2 incubator, and read visually according to the Package Insert. Additionally, the panels may be incubated in and read by a MicroScan® WalkAway instrument. ## Device Story MicroScan® MICroSTREP plus® Panel is a 96-well plastic dish containing dried microdilutions of antimicrobial agents. The device is used to determine the minimum inhibitory concentration (MIC) of Clindamycin for aerobic streptococci. The panel is rehydrated and inoculated with a standardized suspension of the organism in Mueller-Hinton broth supplemented with lysed horse blood. After 20-24 hours of incubation at 35°C, growth is assessed either manually or via the MicroScan® WalkAway instrument. The instrument uses optics light detection to measure growth in each well. The output provides quantitative and qualitative susceptibility results, which assist clinicians in selecting appropriate antibiotic therapy. The device is intended for use in clinical laboratory settings. ## Clinical Evidence Performance validated via external evaluations using CDC challenge strains and fresh/stock clinical isolates. Primary endpoint: Essential Agreement (EA) between instrument-read MIC results and expected results (CLSI frozen reference). Overall EA for Clindamycin was ≥95.7%, including S. pneumoniae. Reproducibility and precision testing performed on the WalkAway® instrument showed acceptable results. ## Technological Characteristics Miniaturized broth dilution panel; rehydrated with Mueller-Hinton broth, 2-5% lysed horse blood, and 50 mM HEPES. Sensing principle: visual or automated optical detection of bacterial growth inhibition. Connectivity: compatible with MicroScan® WalkAway instrument. Software: automated reading algorithm for MIC determination. ## Regulatory Identification An antimicrobial susceptibility test powder is a device that consists of an antimicrobial drug powder packaged in vials in specified amounts and intended for use in clinical laboratories for determining in vitro susceptibility of bacterial pathogens to these therapeutic agents. Test results are used to determine the antimicrobial agent of choice in the treatment of bacterial diseases. ## Predicate Devices - MicroScan® MICroSTREP plus® Panel ## 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} Page 1 of 8 # 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY ASSAY ONLY TEMPLATE A. 510(k) Number: K062777 B. Purpose for Submission: To add the option for automated reading of antibiotic Clindamycin at 0.015 – 2 µg/mL to the MICroSTREP plus® Panel on the MicroScan® WalkAway System, and to remove the “Do not report” limitation for *Streptococcus pneumoniae*. C. Measurand: Clindamycin at 0.015 – 2 µg/mL D. Type of Test: Quantitative and Qualitative growth based detection algorithm using optics light detection E. Applicant: Dade Behring Inc, MicroScan® F. Proprietary and Established Names: MicroScan® MICroSTREP plus® Panel – Clindamycin at 0.015 – 2 µg/mL G. Regulatory Information: 1. Regulation section: 21 CFR 866.1640 – Antimicrobial Susceptibility Test Powder 2. Classification: Class II 3. Product Code: LRG – Instrument for Auto Reader & Interpretation of Overnight Antimicrobial Susceptibility System LTT – Panels, Test, Susceptibility, Antimicrobial 4. Panel: 83 Microbiology H. Intended Use: 1. Intended use(s): Clindamycin at 0.015 – 2 µg/mL is for use with MICroSTREP plus® Panels MICroSTREP plus® Panels are designed for use in determining quantitative {1} Page 2 of 8 and/or qualitative antimicrobial agent susceptibility of colonies grown on solid media of aerobic streptococci, including *Streptococcus pneumoniae*. 2. **Indication(s) for use:** This submission is for adding the option for automated reading of the antibiotic Clindamycin at concentrations of 0.015 – 2 µg/mL to MICroSTREP *plus®* Panels on the MicroScan® WalkAway System, for testing aerobic streptococci including *Streptococcus pneumoniae*, and also for the removal of the “Do not report” limitation for *S. pneumoniae*. 3. **Special condition for use statement(s):** Prescription Use Only Turbidity method of inoculum preparation only 4. **Special instrument Requirements:** Not Applicable I. **Device Description:** The MicroScan® MICroSTREP *plus®* Panel is a 96-well plastic dish which contains microdilutions of each antimicrobic in various concentrations dried in aqueous solutions. The panel is rehydrated and inoculated at the same time with a Mueller-Hinton broth supplemented with lysed horse blood (2 – 5%). The target inoculum concentration for each well should be approximately 5 × 10⁵ colony forming units (CFU)/mL. Panels are incubated in a 35°C non-CO₂ incubator for 20-24 hours. After incubation, the panels are read manually for growth. Additionally, panels may be incubated in and read by a MicroScan® WalkAway instrument. Each panel contains a “growth” but it does not contain a “no growth” control well. J. **Substantial Equivalence Information:** 1. **Predicate device name(s):** MICroSTREP *plus®* 2. **Predicate K number(s):** K021184 3. **Comparison with predicate:** | Similarities | | | | --- | --- | --- | | Item | Device | Predicate | | Results | Quantitative with qualitative interpretations | Same | | Incubation | 20 – 24 hours | Same | | Panels | Clindamycin dried in aqueous solution | Same | {2} | Differences | | | | --- | --- | --- | | Item | Device | Predicate | | Technology | Growth based using algorithm with optics light detection | Growth based | | Intended use | Determination of susceptibility to clindamycin with aerobic streptococci including Streptococcus pneumoniae | Determination of susceptibility to clindamycin with aerobic streptococci, with a limitation for Streptococcus pneumoniae | | Isolates | For use with aerobic streptococci including Streptococcus pneumoniae isolated colonies from culture | For use with aerobic streptococci, other than Streptococcus pneumoniae, isolated colonies from culture | | Reading | Overnight method Manual or automated | Overnight method Manual read only | | Instrument | MicroScan® WalkAway System or Microdilution viewer | Microdilution viewer | # K. Standard/Guidance Document Referenced (if applicable): "Class II Special Controls Guidance Document: Antimicrobial Susceptibility Test (AST) Systems; Guidance for Industry and FDA"; CLSI M7 (M100-S16) "Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically; Approved Standard." # L. Test Principle: The antimicrobial susceptibility tests are miniaturizations of the broth dilution susceptibility test that have been diluted in water and dehydrated. Various antimicrobial agents are diluted in water, buffer or minute concentrations of broth to concentrations bridging the range of clinical interest. Panels are rehydrated with $115~\mu \mathrm{L}$ Mueller-Hinton broth supplemented with $2 - 5\%$ lysed horse blood (LHB), after inoculation of the broth with a standardized suspension of the organism. The target inoculum concentration for each well should be approximately $5\times 10^{5}$ colony forming units (CFU)/mL. After incubation in a non- $\mathrm{CO}_{2}$ incubator for 20-24 hours, the minimum inhibitory concentration (MIC) for the test organisms is determined by observing the lowest antimicrobial concentration showing inhibition of growth. Panels can be read manually using indirect light or the panels can be read on the MicroScan® WalkAway instrument using optics light detection. # M. Performance Characteristics (if/when applicable): This submission is for the AST Panel only. The ID System was not reviewed. The Reproducibility studies, QC performance data, and Challenge isolates evaluated {3} Page 4 of 8 by the manual and automated reading methods are contained in this submission to demonstrate that there is no difference between manual reading and automated reading in the MicroScan® WalkAway System. Efficacy, quality control and challenge data from the external validation of the manual read method are provided for the removal of the “Do not report” limitation for Streptococcus pneumoniae (reference K021184). The limitation was requested in the original submission for S. pneumoniae because of one very major error observed during the Efficacy testing. 1. Analytical performance: a. Precision/Reproducibility: Reproducibility was demonstrated using 10 isolates tested at 3 sites on 3 separate days in triplicate. The study included testing on the MicroScan® WalkAway System with automated reading at 20-24 hours, and manual readings at 20-24 hours incubation. Both reading methods demonstrated >95% reproducibility, and no differences were observed. b. Linearity/assay reportable range: Not applicable c. Traceability, Stability, Expected values (controls, calibrators, or method): The recommended QC isolate S. pneumoniae ATCC 49619 was tested a sufficient number of times with acceptable results on all testing days with the reference method. Quality control results demonstrated the ability of the different reading parameters (manual and instrument) to produce acceptable results. The following table provides the frequency of results in each concentration with the expected range stated. Both reading methods produced the same mode. | Organism | Concentration μg/mL | Reference results | MicroScan® WalkAway results | | | --- | --- | --- | --- | --- | | | | | Manual Overnight | Instrument Overnight | | S. pneumoniae ATCC 49619 Expected range 0.03- 0.12 μg/mL | <=0.015 | | | | | | 0.03 | 1 | 1 | 1 | | | 0.06 | 64 | 64 | 61 | | | 0.12 | | | 3 | | | 0.25 | | | | | | 0.5 | | | | | | 1 | | | | {4} Inoculum density control: A turbidity meter, which was verified each day of testing, was used for the turbidity inoculation method. Colony counts were performed weekly, on the ATCC S. pneumoniae with all results in the expected range of approximately $5 \times 10^{5}$ . No trending was observed. d. Detection limit: Not applicable e. Analytical specificity: Not applicable f. Assay cut-off: Not applicable # 2. Comparison studies: # a. Method comparison with predicate device: # Removal of limitation Clinical efficacy testing with manual result reading was conducted and was described in submission K021184. The original efficacy data are included with this submission for the removal of the "Do no report" limitation for Streptococcus pneumoniae. The clinical protocol, panel descriptions and incubation methods were previously provided in K021184. A total of 492 streptococcal isolates, composed of 231 fresh and 261 stock isolates, were tested at 3 sites. The limitation was requested in the original submission for S. pneumoniae because of one very major error observed during the efficacy testing. The table below displays the efficacy performance for all streptococcal isolates tested, including S. pneumoniae. Efficacy data including Streptococcus pneumoniae against Clindamycin | | EA Tot | EA N | EA % | Eval EA Tot | Eval EA N | Eval EA % | CA N | CA % | # R | min | maj | vmj | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | All streptococcal isolates | 492 | 481 | 97.8 | 354 | 351 | 99.2 | 490 | 99.6 | 41 | 0 | 1 | 1 | Essential agreement (EA) is when the Microscan® MICroSTREP plus® panel agrees with the reference test panel results exactly or within one doubling dilution of the reference method. Category agreement (CA) is when the Microscan® MICroSTREP plus® panel interpretation agrees exactly with the reference panel interpretation. Evaluable (Eval) are results that are within the test range and on scale. {5} Page 6 of 8 There was one very major error generated by the inclusion of the *Streptococcus pneumoniae* isolates data. No additional minor errors or major errors were produced. The maj error rate is 0.2% (1/451). The vmj error rate is 2.4% (1/41). The EA% of 97.8% and the CA% of 99.6% are both very good. The test device had a >95% growth rate, and the performance data are acceptable for removal of the limitation of Clindamycin for *S. pneumoniae*. ## Read method comparison In this submission, Challenge isolates were evaluated by the manual and automated reading methods to demonstrate that there is no difference between manual reading and instrument reading on the MicroScan® WalkAway System. There were 70 challenge isolates including 53 CDC Challenge Set strains, tested at one site and compared to the reference broth dilution result. A comparison was done with readings on the instrument after 20 hours incubation, and also read manually when incubated for 20-24 hours. Performance by the automated reading method was acceptable with no differences or trends. The recommended CLSI reference method was followed with the exception of the use of a small amount (0.1%) of Pluronic (a wetting agent) in the final inoculum. A validation of the use of Pluronic in the frozen reference panel was conducted. QC was also performed with no difference apparent in the results. Read method comparison of *Streptococcus* species and Clindamycin | | EA Tot | EA N | EA % | Eval EA Tot | Eval EA N | Eval EA % | #R | min | maj | vmj | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | Challenge Manual | 70 | 66 | 94.3 | 48 | 47 | 97.9 | 13 | 0 | 1 | 0 | | Challenge Automated | 70 | 67 | 95.7 | 48 | 47 | 97.9 | 13 | 1 | 1 | 0 | EA-Essential Agreement R-resistant isolates maj-major discrepancies vmj-very major discrepancies min- minor discrepancies Essential agreement (EA) is when the Microscan® MICroSTREP plus® panels agree with the reference test panel results exactly or within one doubling dilution of the reference method. Evaluable (Eval) are results that are within the test range and on scale. Automated reading results were the same as the manual reading results with no trending. There were no vmj, and there was 1 maj error for both reading methods; there was 1 additional minor error generated by {6} Page 7 of 8 the automated reading method. The overall EA% of 94.3% and Eval EA% of 97.9% for the manual read and overall EA% of 95.7% and Eval EA% of 97.9% for the automated reading were both very good. The test device had a growth rate of >95% for both the manual reading and the automated reading methods. The comparison of the reading methods demonstrates that the manual reading method and the automated reading on the MicroScan® WalkAway System are no different. The performance data currently documented in the package insert will be updated. 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: Streptococcus species Interpretive Criteria: <=0.25 (Susceptible), 0.5 (Intermediate), >=1 (Resistant) The expected value range, interpretive criteria and QC are included in the package insert. N. Proposed Labeling: The labeling is sufficient and it satisfies the requirements of 21 CFR Part 809.10. O. Conclusion: The submitted information in this premarket notification is complete and supports a substantial equivalence decision. {7} Page 8 of 8 --- **Source:** [https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/LTT/K062777](https://fda.innolitics.com/submissions/MI/subpart-b%E2%80%94diagnostic-devices/LTT/K062777) **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. 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