(168 days)
The Sofia® Strep A+ FIA detects Group A Streptococcal antigens from patients with signs and symptoms of pharyngitis, such as sore throat. All negative test results should be confirmed by bacterial culture because negative results do not preclude Group A Strep infection and should not be used as the sole basis for treatment. The test is intended for professional and laboratory use as an aid in the diagnosis of Group A Streptococcal infection.
The Sofia Strep A FIA employs immunofluorescence technology that is used with the Sofia analyzer (Sofia) to detect Group A Streptococcal antigen. The Sofia Strep A FIA involves the extraction of the antigenic components of the Group A Streptococcus (GAS) bacteria. The patient's swab sample is placed in the Reagent Tube containing the Reagent Solution, during which time the bacterial antigens are extracted, making them more accessible to the specific antibodies. An aliquot of the extracted sample is dispensed into the Cassette sample well. From the sample well, the sample migrates through a test strip containing various unique chemical environments. If Group A Streptococcal antigens are present, they will be bound by antibodies coupled to fluorescent microparticles that migrate through the test strip. The fluorescent microparticles containing bound antigen will be captured by antibodies at a defined location on the test strip where they are detected by Sofia. If antigens are not present, the fluorescent microparticles will not be trapped by the capture antibodies nor detected by Sofia. Note: The Cassette, now containing the sample, is placed directly inside Sofia for automatically timed development (WALK AWAY Mode). Sofia scans, measures, and interprets the immunofluorescent signal using method-specific algorithms. Sofia will display the test results (Positive, Negative, or Invalid) on the screen. The results can also be automatically printed on an integrated printer if this option is selected, or transmitted via an LIS connection.
Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided text:
Device: Sofia® Strep A+ FIA
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state "acceptance criteria" numerically for sensitivity and specificity. However, based on the performance study results, the implied acceptance criteria would be the statistically significant ranges demonstrated by the device.
| Metric | Acceptance Criteria (Implied from performance) | Reported Device Performance (95% CI) |
|---|---|---|
| Sensitivity | > 89.1% (lower bound of 95% CI) | 93.7% (89.1%-96.5%) |
| Specificity | > 92.4% (lower bound of 95% CI) | 94.4% (92.4%-95.9%) |
| PPV | Not explicitly defined, but reported | 81.2% |
| NPV | Not explicitly defined, but reported | 98.3% |
| Reproducibility Inter-laboratory (Negative) | > 95.9% (lower bound of 95% CI) | 100% (95.9-100.0%) |
| Reproducibility Inter-laboratory (High Negative) | > 82.1% (lower bound of 95% CI) | 90% (82.1-94.7%) |
| Reproducibility Inter-laboratory (Low Positive) | > 78.1% (lower bound of 95% CI) | 87% (78.1-92.2%) |
| Reproducibility Inter-laboratory (Mod Positive) | > 95.9% (lower bound of 95% CI) | 100% (95.9-100.0%) |
| Reproducibility Intra-laboratory (Overall Site 1) | > 89.5% (lower bound of 95% CI) | 95% (89.5-97.7%) |
| Reproducibility Intra-laboratory (Overall Site 2) | > 87.4% (lower bound of 95% CI) | 93% (87.4-96.6%) |
| Reproducibility Intra-laboratory (Overall Site 3) | > 88.5% (lower bound of 95% CI) | 94% (88.5-97.2%) |
| Limit of Detection (LoD) | Not explicitly defined as a single criterion, but values must be provided | Ranged from 2.76E+03 to 8.13E+03 cfu/test (for 3 strains) |
| Analytical Reactivity | 100% detection of tested strains at specified concentration | All 21 tested Streptococcus pyogenes strains detected at 1.74E+04 cfu/test. |
| Analytical Specificity (Cross-Reactivity) | No cross-reactivity with non-GAS organisms/viruses at specified concentrations | None of the 61 non-Group A Streptococcus bacterial and fungal microorganisms, and 26 viral isolates showed any sign of cross-reactivity. |
| Interfering Substances | No interference at specified concentrations | Most substances did not interfere. Nacho Flavor Doritos interfered at 25% w/v and Fresh Whole Blood interfered at 100 µL/swab. Bovine submaxillary mucin interfered at 28.7 mg/mL. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Clinical Performance Study: 851 patients.
- Data Provenance: Retrospective, collected during 2014 from 7 distinct CLIA-waived sites in various geographical regions within the United States.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The document does not explicitly state the number of experts or their qualifications for interpreting the ground truth (bacterial culture and PCR). However, it mentions:
- "A central Reference Laboratory" conducted the bacterial culture and PCR. This implies qualified laboratory personnel.
4. Adjudication Method for the Test Set
The primary comparison was against standard bacterial culture. For discordant results between the Sofia Strep A+ FIA and culture, an "FDA-cleared molecular device" (RT-PCR assay) was used for resolution.
- Method: Initial comparison of Sofia Strep A+ FIA to bacterial culture.
- Discordant Resolution: For specimens where Sofia Strep A+ FIA and culture disagreed, an FDA-cleared molecular device (PCR) was used to resolve the discrepancy. This is a 2-step adjudication approach (initial culture, then PCR for discrepancies).
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study comparing human readers with and without AI assistance was not done. This study is for a diagnostic device (FIA) that measures antigens, not an AI-powered image analysis system that would assist human readers in interpretation.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Yes, the clinical performance study directly evaluated the "rapid FIA test result" from the Sofia Strep A+ FIA against the ground truth. The device itself (Sofia Strep A+ FIA with the Sofia analyzer) provides the result (Positive, Negative, or Invalid) and automatically interprets the immunofluorescent signal using method-specific algorithms, thus representing a standalone performance evaluation.
7. The Type of Ground Truth Used
The ground truth for the clinical performance study consisted of:
- Bacterial Culture: Throat swabs were streaked on a sheep blood agar plate (SBA) and cultured for up to 48 hours.
- Molecular (PCR): An FDA-cleared Group A Streptococcus RT-PCR assay was used to resolve discordant results between the device and primary culture. This is a combination of culture and a highly sensitive molecular method.
8. The Sample Size for the Training Set
The document does not specify a separate "training set" sample size. This type of device (immunofluorescence assay) doesn't typically undergo a machine learning training phase in the same way an AI-powered diagnostic algorithm would. The development of its "method-specific algorithms" would be based on analytical studies (LoD, cross-reactivity, precision) to define positive/negative thresholds rather than a distinct training dataset of patient samples.
9. How the Ground Truth for the Training Set Was Established
As noted above, a traditional "training set" with ground truth in the context of machine learning is not applicable here. The "method-specific algorithms" in the Sofia analyzer would have been developed and validated based on extensive analytical studies to establish appropriate thresholds for signal detection and interpretation. These analytical studies involved:
- Serial dilutions of known concentrations of Streptococcus pyogenes strains (for LoD).
- Testing against known non-Group A Streptococcus organisms and various viruses at specific concentrations (for analytical specificity/cross-reactivity).
- Testing with potential interfering substances at defined concentrations.
These analytical studies establish the performance characteristics that dictate how the device's inherent algorithms classify a result, rather than a separate "training set" of patient data.
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Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002
QUIDEL CORPORATION December 16, 2014 JOHN TAMERIUS SENIOR VICE PRESIDENT, CLINICAL AND REGULATORY 12544 HIGH BLUFF (ADMINISTRATIVE OFFICE LOCATION) SAN DIEGO CA 92130
Re: K141775
Trade/Device Name: Sofia® Strep A+ FIA Regulation Number: 21 CFR 866.3740 Regulation Name: Streptococcus spp. serological reagents Regulatory Class: I Product Code: GTY Dated: June 30, 2014 Received: July 1, 2014
Dear Dr. Tamerius:
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.
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Sally A. Hojvat, M.Sc., Ph.D. Director Division of Microbiology Devices Office of In Vitro Diagnostics and Radiological Health Center for Devices and Radiological Health
Enclosure
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DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration
Indications for Use
510(k) Number (if known) K141775
Device Name Sofia® Strep A+FIA Assay
Indications for Use (Describe)
The Sofia® Strep A+ FIA detects Group A Streptococcal antigens from patients with signs and symptoms of pharyngitis, such as sore throat. All negative test results should be confirmed by bacterial culture because negative results do not preclude Group A Strep infection and should not be used as the sole basis for treatment. The test is intended for professional and laboratory use as an aid in the diagnosis of Group A Streptococcal infection.
Type of Use (Select one or both, as applicable)
X Prescription Use (Part 21 CFR 801 Subpart D)
__ Over-The-Counter Use (21 CFR 801 Subpart C)
PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON A SEPARATE PAGE IF NEEDED.
FOR FDA USE ONLY
Concurrence of Center for Devices and Radiological Health (CDRH) (Signature)
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510(k) SUMMARY
| Submitted By: | Quidel Corporation12544 High Bluff Drive, Suite 200(Administrative Offices)San Diego, California 92130Telephone: 858-552-7908Fax: 858-646-8045 |
|---|---|
| Submission Contact: | John D. Tamerius, Ph.D. |
| Date Prepared: | June 30, 2014 |
| Device Trade Name: | Sofia® Strep A+ FIA and Sofia |
| Common Name: | Strep A immunological test system and Fluorometer |
| Predicate Devices: | Sofia Strep A FIA for use with Sofia, K123793 |
| Device Classification/Name: | 21 CFR 866.3740 / Streptococcus Group Aserological reagents |
| Intended Use: | The Sofia Strep A+ FIA detects Group AStreptococcal antigens from throat swabs frompatients with signs and symptoms of pharyngitis, suchas sore throat. All negative test results should beconfirmed by bacterial culture because negativeresults do not preclude Group A Strep infection andshould not be used as the sole basis for treatment.The test is intended for professional and laboratoryuse as an aid in the diagnosis of Group AStreptococcal infection. |
| Physiologic Basis of theTest: | Group A Streptococcus is one of the most commoncauses of acute upper respiratory tract infection. Earlydiagnosis and treatment of Group A Streptococcalpharyngitis has been shown to reduce the severity ofsymptoms and serious complications such asrheumatic fever and glomerulonephritis.Conventional procedures for identification of Group AStreptococcus from throat swabs involve the culture,isolation, and subsequent identification of viablepathogen at 24 to 48 hours or longer for results. |
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Device Description: The Sofia Strep A FIA employs immunofluorescence technology that is used with the Sofia analyzer (Sofia) to detect Group A Streptococcal antigen.
The Sofia Strep A FIA involves the extraction of the antigenic components of the Group A Streptococcus (GAS) bacteria. The patient's swab sample is placed in the Reagent Tube containing the Reagent Solution, during which time the bacterial antigens are extracted, making them more accessible to the specific antibodies. An aliquot of the extracted sample is dispensed into the Cassette sample well. From the sample well, the sample migrates through a test strip containing various unique chemical environments. If Group A Streptococcal antigens are present, they will be bound by antibodies coupled to fluorescent microparticles that migrate through the test strip. The fluorescent microparticles containing bound antigen will be captured by antibodies at a defined location on the test strip where they are detected by Sofia. If antigens are not present, the fluorescent microparticles will not be trapped by the capture antibodies nor detected by Sofia.
Note: The Cassette, now containing the sample, is placed directly inside Sofia for automatically timed development (WALK AWAY Mode).
Sofia scans, measures, and interprets the immunofluorescent signal using method-specific algorithms. Sofia will display the test results (Positive, Negative, or Invalid) on the screen. The results can also be automatically printed on an integrated printer if this option is selected, or transmitted via an LIS connection.
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Device Comparison:
Note: The shaded cells in Table 1 below identify where there are differences between the proposed and predicate devices.
| Item | Proposed Device | Predicate Device |
|---|---|---|
| Features | Sofia Strep A+ FIA with Sofia | Sofia Strep A FIA with Sofia |
| Intended Use | The Sofia® Strep A+ FIA detectsGroup A Streptococcal antigensfrom throat swabs from patientswith signs and symptoms ofpharyngitis, such as sore throat.All negative test results should beconfirmed by bacterial culturebecause negative results do notpreclude Group A Strep infectionand should not be used as thesole basis for treatment. The testis intended for professional andlaboratory use as an aid in thediagnosis of Group AStreptococcal infection. | The Sofia Strep A FIA employsimmunofluorescence technology todetect Group A Streptococcalantigens from throat swabs ofsymptomatic patients. All negativetest results should be confirmed bybacterial culture because negativeresults do not preclude Group AStrep infection and should not beused as the sole basis fortreatment. The test is intended forprofessional and laboratory use asan aid in the diagnosis of Group AStreptococcal infection. |
| FDA FileNumber | K141775 | K123793 |
| Manufacturer | Quidel Corporation and LRE | Quidel Corporation and LRE |
| RegulationNumber | 21 CFR 866.3740 and21 CFR 866.2560 | 21 CFR 866.3740 and21 CFR 866.2560 |
| ClassificationProduct Code | GTY and KHO | GTY and KHO |
| Instrument | Sofia | Sofia |
| Analyte | Group A Streptococcus | Group A Streptococcus |
| AutomatedAnalysis | Yes | Yes |
| Mode(s) | Walk-Away only | Read-Now and Walk-Away |
| Read Results | Read results on instrument screenor print with optional printer | Read results on instrument screenor print with optional printer |
| Calibrator | Yes - Calibration Cassette andQC Card provided | Yes - Calibration Cassette andQC Card provided |
| Read ResultTime | 5 Minutes | 5 Minutes |
| SpecimenTypes | Throat swab | Throat swab |
| Qualitative | Yes | Yes |
| Test Principle | Immunofluorescence Device | Immunofluorescence Device |
| Item | Proposed Device | Predicate Device |
| Features | Sofia Strep A+ FIA with Sofia | Sofia Strep A FIA with Sofia |
| Format | Lateral-flow Test Cassette | Lateral-flow Test Cassette |
| AntibodiesUsed | Polyclonal rabbit antibodies thatare specific to Group AStreptococcus | Polyclonal rabbit antibodies thatare specific to Group AStreptococcus |
| DetectionParticle | Polystyrene microparticles dyedwith Europium chelate | Polystyrene microparticles dyedwith Europium chelate |
| Storage | Room Temperature | Room Temperature |
| ReagentSolution | One reagent bottle containingsodium nitrite and hydrochloricacid in glass ampoule | One reagent bottle containingsodium nitrite and acetic acid inglass ampoule |
| TransferDevice | Fixed volume pipette used totransfer patient sample mixed withreagent into Test Cassette | Fixed volume pipette used totransfer patient sample mixed withreagent into Test Cassette |
| ExternalControls | Test kit contains Positive andNegative Control Swabs | Test kit contains Positive andNegative Control Swabs |
| Quality ControlFeatures | Built-in features include:• Built-in procedural controlzone scanned by theanalyzer to determinewhether adequate flowoccurred• Analyzer prevents used orexpired cartridge from beingread by the reader• Cassette properly inserted | Built-in features include:• Built-in procedural controlzone scanned by theanalyzer to determinewhether adequate flowoccurred• Analyzer prevents used orexpired cartridge from beingread by the reader• Cassette properly inserted |
Table 1
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Summary of Performance Data:
Sofia Strep A+ FIA Performance vs. Cell Culture and vs. Cell Culture Resolved by PCR
The performance of the Sofia Strep A+ FIA was compared to standard bacterial culture and identification and an FDA-cleared Group A Streptococcus RT-PCR assay in a multi-center clinical field study. This study was conducted by untrained health care personnel during 2014 at 7 distinct CLIA-waived sites in various geographical regions within the United States. In this multicenter, point-of-care (POC) field trial, two (2) throat swabs were collected from eight hundred fiftyone (851) patients with symptoms suggestive of bacterial pharyngitis.
One throat swab was tested fresh at the CLIA-waived site in the Sofia Strep A+ FIA. A second swab was placed into transport medium and transported on cold ice packs to a central Reference Laboratory. The swab was streaked on a sheep blood agar plate (SBA) and cultured for up to 48 hours. A portion of the transport medium was subsequently tested in the PCR assay. The performance of the Sofia Strep A+ FIA was determined by comparison of the rapid FIA test result to the corresponding culture result (Table 2).
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Table 2 Sofia Strep A+ FIA Performance Compared to Culture
| Culture | |||
|---|---|---|---|
| Pos | Neg | Sensitivity | |
| Sofia Pos | 164 | 38* | 93.7% (164/175)(95%CI=89.1%-96.5%) |
| Sofia Neg | 11** | 638 | Specificity |
| 94.4% (638/676)(95% CI=92.4%-95.9%) | |||
| Total: | 175 | 676 | PPV |
| 81.2% (164/202) | |||
| NPV | |||
| 98.3% (638/649) |
*Of the 38 discordant specimens, 24 of these specimens were positive for GAS when tested with an FDA-cleared molecular device, 14 were negative.
**Of the 11 discordant specimens, 3 were negative when tested with an FDA-cleared molecular device, 8 were positive.
Reproducibility Studies
The reproducibility of the Sofia Strep A+ FIA was evaluated at 3 different laboratories. Two different operators at each site tested a series of coded, contrived samples, prepared in negative clinical matrix, ranging from negative (no bacteria) to moderate positive (3 x LoD) Group A Streptococcus. The inter-laboratory agreement (Table 3) for negative samples was 90-100% and 87-100% for positive samples. The intra-laboratory agreement (Table 4) for all samples ranged from 93-95%.
| Site | Negative*(C₀) | High Negative*(C₅) | Low Positive**(C₉₅) | Mod Positive**(C₁₀₀) |
|---|---|---|---|---|
| 1 | 30/30 | 27/30 | 27/30 | 30/30 |
| 2 | 30/30 | 29/30 | 23/30 | 30/30 |
| 3 | 30/30 | 25/30 | 28/30 | 30/30 |
| Total | 90/90 | 81/90 | 78/90 | 90/90 |
| % OverallAgreement(95% CI) | 100%(95.9-100.0%) | 90%(82.1-94.7%) | 87%(78.1-92.2%) | 100%(95.9-100.0%) |
Table 3 Sofia Strep A+ FIA Reproducibility Study Inter-laboratory Agreement
*Bacteria not detected/total
**Bacteria detected/total
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Table 4 Sofia Strep A+ FIA Reproducibility Study Intra-laboratory Agreement
| Site | Negative*(Co) | High Negative*(Cis) | Low Positive**(C95) | Mod. Positive**(C100) | % OverallAgreement(95% CI) |
|---|---|---|---|---|---|
| 1 | 30/30 | 27/30 | 27/30 | 30/30 | 95% (114/120)(89.5-97.7%) |
| 2 | 30/30 | 29/30 | 23/30 | 30/30 | 93% (112/120)(87.4-96.6%) |
| 3 | 30/30 | 25/30 | 28/30 | 30/30 | 94% (113/120)(88.5-97.2%) |
*Bacteria not detected/total
**Bacteria detected/total
Limit of Detection
The limit of detection (LoD) for the Sofia Strep A+ FIA was determined using 3 strains of Group A Streptococcus pyogenes. The LoD ranged from 2.76E+03 to 8.13E+03 colony forming units (cfu)/test (Table 5).
Table 5 Sofia Strep A+ FIA Limits of Detection
| Strain | Minimum Detectable Level* |
|---|---|
| Bruno [CIP 104226] | 4.00E+03 cfu/test |
| CDC-SS-1402 | 8.13E+03 cfu/test |
| CDC-SS-1460 | 2.76E+03 cfu/test |
cfu/test = colony forming units/test
*The levels of bacteria were determined by limiting dilution, bacterial culture, and colony counting to give cfu/test.
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Analytical Reactivity
Analytical reactivity for the Sofia Strep A+ FIA was demonstrated using 21 strains of Group A Streptococcus pyogenes tested at 1.74E+04 colony forming units (cfu)/test (Table 6).
| Streptococcus pyogenes Strain |
|---|
| Strain #1 (ATCC-19615) |
| Strain #2 (ATCC-700942) |
| Strain #3 (ATCC-700952) |
| Strain #4 (Clinical Isolate-52123) |
| Strain #5 (Clinical Isolate-52120) |
| Strain #6 (Clinical Isolate-62055) |
| Strain #7 (Clinical Isolate-52152) |
| Strain #8 (Clinical Isolate-62092) |
| Strain #9 (Clinical Isolate-52151) |
| Strain #10 (ATCC-700482) |
| Strain #11 (ATCC-BAA-1315) |
| Strain #12 (ATCC-700459) |
| Strain #13 (ATCC-12203) |
| Strain #14 (ATCC-700944) |
| Strain #15 (Clinical Isolate-52154) |
| Strain #16 (Clinical Isolate-5036) |
| Strain #17 (Clinical Isolate-5095) |
| Strain #18 (Clinical Isolate-5017) |
| Strain #19 (Clinical Isolate-5060) |
| Strain #20 (Clinical Isolate-5112) |
| Strain #21 (Clinical Isolate-5008) |
Table 6 Analytical Reactivity
Analytical Specificity
Cross Reactivity
The cross reactivity of the Sofia Strep A+ FIA was evaluated with a total of 61 non-Group A Streptococcus bacterial and fungal microorganisms, and 26 viral isolates. None of the microorganisms or viruses listed below in Table 7 showed any sign of cross reactivity in the assay. The same microorganisms and viruses in Table 7 were pre-mixed with Group A Strep and tested in the Sofia Strep A+ FIA.
| Table 7 |
|---|
| Cross Reactivity |
| Organism/Virus | Test Concentration** |
|---|---|
| Arcanobacterium haemolyticum | 3.00E+05 cfu/test |
| Bacteroides fragilis | 3.00E+07 cfu/test |
| Bordetella pertussis | 3.00E+07 cfu/test |
| Candida albicans | 3.00E+04 cfu/test |
| Corynebacterium diphtheriae | 3.00E+05 cfu/test |
| Corynebacterium pseudodiphtheriticum* | 3.00E+06 cfu/test |
| Enterococcus faecalis* | 1.40E+06 cfu/test |
| Organism/Virus | Test Concentration** |
| Enterococcus faecium | 3.00E+06 cfu/test |
| Escherichia coli | 1.50E+07 cfu/test |
| Fusobacterium necrophorum | 3.00E+06 cfu/test |
| Haemophilus influenzae | 3.00E+07 cfu/test |
| Haemophilus parahaemolyticus | 3.00E+06 cfu/test |
| Klebsielle pneumoniae | 3.00E+07 cfu/test |
| Moraxella catarrhalis | 3.00E+06 cfu/test |
| Neisseria gonorrhoeae | 3.00E+06 cfu/test |
| Neisseria lactamica | 3.00E+06 cfu/test |
| Neisseria meningitidis | 3.00E+06 cfu/test |
| Neisseria sicca | 3.00E+07 cfu/test |
| Neisseria subflava | 3.00E+07 cfu/test |
| Proteus vulgaris | 3.00E+07 cfu/test |
| Pseudomonas aeruginosa | 3.00E+06 cfu/test |
| Serratia marcescens | 3.00E+07 cfu/test |
| Staphylococcus aureus* | 3.00E+06 cfu/test |
| Staphylococcus epidermidis | 3.00E+06 cfu/test |
| Staphylococcus haemolyticus | 3.00E+05 cfu/test |
| Staphylococcus intermedius | 3.00E+05 cfu/test |
| Staphylococcus saprophyticus | 3.00E+06 cfu/test |
| Streptococcus anginosus | 3.00E+06 cfu/test |
| Streptococcus gordonii | 3.00E+04 cfu/test |
| Streptococcus mitis | 3.00E+04 cfu/test |
| Streptococcus mutans* | 3.00E+06 cfu/test |
| Streptococcus oralis | 3.00E+06 cfu/test |
| Streptococcus parasanginis* | 3.00E+06 cfu/test |
| Streptococcus pneumoniae | 3.00E+06 cfu/test |
| Streptococcus salivaris | 3.00E+05 cfu/test |
| Streptococcus sanguinis | 3.00E+06 cfu/test |
| Streptococcus Group B Strain #1:Streptococcus agalactiae | 3.00E+06 cfu/test |
| Streptococcus Group B Strain #2 | 3.00E+06 cfu/test |
| Streptococcus Group B Strain #3 | 3.00E+06 cfu/test |
| Streptococcus Group B Strain #4 | 3.00E+06 cfu/test |
| Streptococcus Group B Strain #5 | 3.00E+06 cfu/test |
| Streptococcus Group C Strain #1 | 3.00E+06 cfu/test |
| Streptococcus Group C Strain #2 | 3.00E+06 cfu/test |
| Streptococcus Group C Strain #3 | 3.00E+06 cfu/test |
| Streptococcus Group C Strain #4:Streptococcus dysgalactiae* | 3.00E+06 cfu/test |
| Organism/Virus | Test Concentration** |
| Streptococcus Group C Strain #5 | 3.00E+05 cfu/test |
| Streptococcus Group D Strain #1:Enterococcus casseliflavus | 3.00E+06 cfu/test |
| Streptococcus Group D Strain #2 | 3.00E+06 cfu/test |
| Streptococcus Group D Strain #3* | 3.00E+06 cfu/test |
| Streptococcus Group D strain #4:Enterococcus faecalis | 3.00E+06 cfu/test |
| Streptococcus Group D strain #5:Enterococcus faecalis | 3.00E+06 cfu/test |
| Streptococcus Group F Strain #1 | 1.00E+05 cfu/test |
| Streptococcus Group F Strain #2 | 3.00E+06 cfu/test |
| Streptococcus Group F Strain #3 | 1.00E+06 cfu/test |
| Streptococcus Group F Strain #4* | 3.00E+05 cfu/test |
| Streptococcus Group F Strain #5 | 3.00E+05 cfu/test |
| Streptococcus Group G strain #1:Streptococcus dysgalactiae | 3.00E+07 cfu/test |
| Streptococcus Group G Strain #2 | 3.00E+06 cfu/test |
| Streptococcus Group G Strain #3 | 3.00E+06 cfu/test |
| Streptococcus Group G Strain #4 | 3.00E+06 cfu/test |
| Streptococcus Group G Strain #5 | 3.00E+06 cfu/test |
| Adenovirus Type 1* | 3.00E+11 TCID50/test |
| Adenovirus Type 3* | 3.00E+05 TCID50/test |
| Adenovirus Type 4 | 7.50E+03 TCID50/test |
| Adenovirus Type 5 | 3.00E+05 TCID50/test |
| Adenovirus Type 11 | 3.00E+04 TCID50/test |
| Coronavirus 229E | 3.00E+04 TCID50/test |
| Coronavirus OC43 | 3.00E+04 TCID50/test |
| Coxsackievirus B5 (Faulkner) | 3.00E+06 TCID50/test |
| Cytomegalovirus (Towne) | 3.00E+03 TCID50/test |
| Echovirus Type 3 | 1.50E+04 TCID50/test |
| Epstein Barr Virus (EBV)* | 3.00E+07 genomecopies/test |
| Herpes Simplex Virus 1 | 3.00E+04 TCID50/test |
| Herpes Simplex Virus 2 | 3.00E+04 TCID50/test |
| Influenza A/New Jersey/8/76 (H1N1) | 3.00E+04 TCID50/test |
| Influenza A/Victoria/3/75 (H3N2) | 3.00E+04 TCID50/test |
| Influenza B/Hong Kong/5/72 | 3.00E+04 TCID50/test |
| Influenza B/Panama/45/90 | 1.50E+04 TCID50/test |
| Influenza C/Taylor/1233/47 | 1.50E+04 TCID50/test |
| Measles (Edmonston) | 3.00E+04 TCID50/test |
| Mumps (Enders)* | 3.00E+03 TCID50/test |
| Organism/Virus | Test Concentration** |
| Parainfluenza virus 1 | 3.00E+04 TCID50/test |
| Parainfluenza virus 2 | 1.10E+05 TCID50/test |
| Parainfluenza virus 3 | 6.80E+05 TCID50/test |
| Parainfluenza virus 4A | 3.00E+04 TCID50/test |
| Rhinovirus Type 2 | 3.00E+03 TCID50/test |
| Rhinovirus Type 15 | 3.00E+04 TCID50/test |
{11}------------------------------------------------
{12}------------------------------------------------
{13}------------------------------------------------
cfu/test = colony forming units/test TCID50/test = 50% tissue culture infectious dose
*This organism/virus may interfere with this assay.
**The levels of bacteria were determined by limiting dilution, bacterial culture, and colony counting to give cfu/test. Virus concentrations were determined by standard virology methods, Reed-Muench.
Interfering Substances
Several over-the-counter (OTC) products, whole blood, mucin and blood agar were evaluated with the Sofia Strep A+ FIA at the levels tested (Table 8).
Table 8 Interference Testing
| Substance | Concentration |
|---|---|
| Crest Pro-Health Deep Clean Mint Mouth wash (Cetylpyridinium chloride) | 24% v/v |
| Listerine Original Antiseptic Mouth wash (Eucalyptol, Menthol, Methyl salicylate, and Thymol) | 24% v/v |
| Listerine Cool Mint Antiseptic Mouth wash (Eucalyptol, Menthol, Methyl salicylate, and Thymol) | 24% v/v |
| RiteAid Sore throat relief (Benzocaine and Menthol) | 24% v/v |
| Chloraseptic Max Sore Throat (Phenol and Glycerin) | 24% v/v |
| Dimetapp Children's Cold & Cough (Brompheniramine maleate, Dextromethorphan HBr, and Phenylephrine HCI) | 24% v/v |
| RiteAid Children's Cold & Allergy (Brompheniramine maleate and Phenylephrine HCI) | 24% v/v |
| CVS Children's Cold & Cough DM (Brompheniramine maleate, Dextromethorphan HBr, and Phenylephrine HCI) | 24% v/v |
| RiteAid tussin cough&cold mucus relief CF (Dextromethorphan HBr, Guaifenesin, and Phenylephrine HCI) | 24% v/v |
| Robitussin Max Strength Multi-Symptom CF Max (Dextromethorphan HBr, Guaifenesin, and Phenylephrine HCI) | 24% v/v |
| Robitussin Night Time Multi-Symptom Cold CF (Acetaminophen, Diphenhydramine HCl, and Phenylephrine HCI) | 24% v/v |
| Cepacol Sore Throat Cherry (Benzocaine and Menthol) | 24% w/v |
| Halls Triple Soothing Action Cherry (Menthol) | 24% w/v |
| Halls Triple Soothing Action Menthol-lyptus (Menthol) | 24% w/v |
| Ricola Natural Herb Cough Drops (Menthol) | 24% w/v |
| Sucrets Complete Vapor Cherry (Dyclonine Hydrochloride and Menthol) | 24% w/v |
| Chloraseptic Sore Throat Cherry (Phenol and Glycerin) | 24% w/v |
| BreathSavers Spearmint (Cetylpyridinium chloride) | 24% w/v |
{14}------------------------------------------------
| Substance | Concentration |
|---|---|
| Tic Tac freshmints (Eucalyptol, Menthol, Methyl salicylate, and Thymol) | 24% w/v |
| Cheetos, Flaming Hot | 12% w/v |
| Doritos, Nacho Flavor | 12% w/v* |
| Fresh Whole Blood | 75 µL/swab** |
| Mucin | 4.3% w/v*** |
| Sheep Blood Agar (5% Sheep Blood) | 24% w/v |
| Horse Blood Agar (5% Horse Blood) | 24% w/v |
*Nacho Flavor Doritos interfered at 25% w/v
** Fresh Whole Blood interfered at 100 µL/swab
14 100n Whole Blood Intonered at 100 perowas
*** Bovine submaxillary mucin interfered at 28.7 mg/mL
Conclusion:
These studies demonstrated the substantial equivalence of the Sofia Strep A+ FIA with the Sofia to the existing product Sofia Strep A FIA with Sofia (K123793).
§ 866.3740
Streptococcus spp. serological reagents.(a)
Identification. Streptococcus spp. serological reagents are devices that consist of antigens and antisera (excluding streptococcal exoenzyme reagents made from enzymes secreted by streptococci) used in serological tests to identifyStreptococcus spp. from cultured isolates derived from clinical specimens. The identification aids in the diagnosis of diseases caused by bacteria belonging to the genusStreptococcus and provides epidemiological information on these diseases. Pathogenic streptococci are associated with infections, such as sore throat, impetigo (an infection characterized by small pustules on the skin), urinary tract infections, rheumatic fever, and kidney 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.