(88 days)
Not Found
No
The device is a chromogenic culture medium for the qualitative detection of bacteria, which relies on chemical reactions and visual interpretation, not AI/ML.
No
The device is a chromogenic medium intended for in vitro diagnostic purposes to aid in the qualitative determination of Group B Streptococcus colonization, and it explicitly states it is "not intended to diagnose infection nor to guide or monitor treatment for infections."
No
The "Intended Use / Indications for Use" section explicitly states, "chromID® Strepto B agar is not intended to diagnose infection nor to guide or monitor treatment for infections." It is intended to aid in the qualitative determination of Group B Streptococcus (GBS) colonization.
No
The device is a selective chromogenic agar medium, which is a physical substance used in a laboratory setting, not a software program.
Yes, this device is an IVD (In Vitro Diagnostic).
Here's why:
- Intended Use: The intended use explicitly states that the device is "intended to aid in the qualitative determination of Group B Streptococcus (GBS) colonization in pregnant women." This is a diagnostic purpose, specifically identifying the presence of a particular organism.
- Sample Type: The test is performed on "vaginal/rectal swabs obtained from pregnant women," which are human specimens.
- Testing Location: The device is intended for use by "laboratory health practitioners in a clinical laboratory," which is the typical setting for IVD testing.
- Device Description: The description details the components of the medium and how it interacts with the sample to produce a result (color change of colonies).
- Performance Studies: The document includes detailed descriptions of analytical and clinical performance studies, including sensitivity and specificity, which are standard for evaluating IVD devices.
- Predicate Device: A predicate device (Modified Selective Streptococcus Agar) is listed with a K number (K881577), indicating a previous FDA clearance for a similar IVD device.
All of these factors align with the definition and characteristics of an In Vitro Diagnostic device.
N/A
Intended Use / Indications for Use
chromID® Strepto B agar is a selective chromogenic medium that is intended to aid in the qualitative determination of Group B Streptococcus (GBS) colonization in pregnant women. This medium supports the growth of, but does not differentiate between, hemolytic GBS strains. The test is performed on 18-24 hour LIM broth enrichments of vaginal/rectal swabs obtained from pregnant women. chromID® Strepto B agar results can be interpreted after 24 hours incubation with confirmation of characteristic GBS colonies from the media.
chromID® Strepto B agar is not intended to diagnose infection nor to guide or monitor treatment for infections. chromID® Strepto B agar does not provide susceptibility results. Subculture to non-selective media should be performed as needed for susceptibility testing, chromID® Strepto B agar is intended for use by laboratory health practitioners in a clinical laboratory.
Product codes (comma separated list FDA assigned to the subject device)
POZ
Device Description
chromID Strepto B agar consists of a nutritive base combining different peptones, chromogenic substrates and antibiotics. These components enable the screening of S. agalactiae by the spontaneous appearance of pale pink to red colonies. Most other bacterial species and yeasts do not grow on this medium or do not produce typical colonies.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
vaginal/rectal swabs
Indicated Patient Age Range
pregnant women
Intended User / Care Setting
laboratory health practitioners in a clinical laboratory.
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Analytical Studies:
- Recovery Study: Two well-characterized GBS strains (ATCC 12386, hemolytic and ATCC 13813, non-hemolytic) were tested.
- Analytical Reactivity (Challenge): A challenge set of 20 GBS strains (hemolytic and non-hemolytic) was inoculated.
- Analytical Specificity (Cross Reactivity): 88 strains representing bacterial and fungal species potentially encountered in vaginal/rectal samples were inoculated.
- Mixed Infection: Seven non-target organisms were tested, including strains known to produce pale pink to red colonies on chromID® Strepto B medium from the Cross Reactivity Study. Two GBS strains (one hemolytic and one non-hemolytic) were incubated with each non-target organism.
- Incubation: Ten (10) GBS strains (hemolytic and non-hemolytic) were inoculated.
- Interfering Substances: 15 interfering substances were tested.
Clinical Studies:
- Reproducibility: Evaluated with 11 organisms including one non-hemolytic strain of Streptococcus agalactiae, and one Staphylococcus aureus strain. Tested at three trial sites.
- Quality Control: Two quality control organisms (Streptococcus agalactiae ATCC 12386, positive control; Staphylococcus aureus ATCC 6538, negative control) tested at each study site by chromID Strepto B agar on each day of comparative and reproducibility testing.
- Prospective Clinical Study: Conducted at three external sites with fresh clinical specimens. A total of 681 vaginal/rectal specimens enriched in LIM broth per CDC guidelines were analyzed. Positive results for chromID Strepto B agar were defined as the growth of pale pink to red colonies. All colony types growing on chromID Strepto B agar were characterized using gram stain, catalase, PYR testing, and latex agglutination. VITEK® MS was used to identify all organisms growing on chromID® Strepto B agar. For the Reference Culture Method, turbid LIM broth cultures were subcultured to CNA agar, and suspicious colonies were screened using gram stain, catalase, PYR testing, and latex agglutination. VITEK MS was also used to confirm GBS identification by the Reference Method.
Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
Analytical Studies:
- Analytical Reactivity (Challenge): 12/20, 17/20 and 20/20 strains were detected on the chromID® Strepto B medium after 18, 24 and 48 hours, respectively.
- Analytical Specificity (Cross Reactivity): After 24 hours, 20/88 strains grew with 3 strains producing characteristic colonies (Streptococcus Group C, Streptococcus mitis, and Klebsiella pneumoniae (KPC)). After 48 hours, 30/88 grew with 6 strains producing characteristic colonies (Streptococcus Group C, Streptococcus mitis, Streptococcus pyogenes, Streptococcus anginosus, Staphylococcus aureus (MRSA), Lactobacillus sakei).
- Mixed Infection: At 24 hrs, both GBS strains were detected in the presence of 10^8 CFU/ml of non-target organism, except in the presence of Streptococcus Group C (NCTC 8546). 5/7 non-target organisms gave characteristic colonies at 10^8 CFU/ml.
- Incubation: The number of strains showing characteristic colonies ranged between 5/10 (at 16 and 17 hours) and 10/10 from 44 hours and after. At 24 hours, 8/10 GBS strains showed characteristic colonies.
- Interfering Substances: No interference was observed for vaginal fluid, amniotic fluid, sperm, whole blood, concentrated buffy coat and stool. Two substances (naproxen sodium and topical agent) demonstrated partial inhibition of GBS growth.
Clinical Studies:
- Reproducibility: Expected results were obtained 100% of the 990 times tested.
- Quality Control: The results for chromID Strepto B agar were 100% correct for the 107 times tested.
- Prospective Clinical Study:
- Comparison of chromID® Strepto B at 24 hours to the Reference Culture Method resulted in a Sensitivity of 97.7% (95% CI: 94.3% - 99.1%) and Specificity of 92.1% (95% CI: 89.4 % - 94.1%).
- At 24 hours, a total of 212 cultures were positive by chromID Strepto B and 176 were positive by the Reference Method.
- Of the 40 false positive cultures, four were confirmed as GBS positive. The remaining 36 demonstrated pale pink to red colored colonies that were not confirmed as GBS.
- The prevalence of GBS detected by the Reference Culture Method was 25.8% (176/681).
Key Metrics (Sensitivity, Specificity, PPV, NPV, etc.)
Sensitivity: 97.7% (95% CI: 94.3% - 99.1%)
Specificity: 92.1% (95% CI: 89.4 % - 94.1%)
Predicate Device(s): If the device was cleared using the 510(k) pathway, identify the Predicate Device(s) K/DEN number used to claim substantial equivalence and list them here in a comma separated list exactly as they appear in the text. List the primary predicate first in the list.
Reference Device(s): Identify the Reference Device(s) K/DEN number and list them here in a comma separated list exactly as they appear in the text.
Not Found
Predetermined Change Control Plan (PCCP) - All Relevant Information for the subject device only (e.g. presence / absence, what scope was granted / cleared under the PCCP, any restrictions, etc).
Not Found
§ 866.2360 Selective culture medium.
(a)
Identification. A selective culture medium is a device that consists primarily of liquid or solid biological materials intended for medical purposes to cultivate and identify certain pathogenic microorganisms. The device contains one or more components that suppress the growth of certain microorganisms while either promoting or not affecting the growth of other microorganisms. The device aids in the diagnosis of disease caused by pathogenic microorganisms and also provides epidemiological information on these diseases.(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 the limitations in § 866.9.
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Image /page/0/Picture/1 description: The image shows the logo for the Department of Health & Human Services - USA. The logo is a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" written around the perimeter. Inside the circle is an abstract image of three human profiles facing to the right, stacked on top of each other.
Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002
January 27, 2017
BIOMERIEUX, INC. KAREN RUSSELL STAFF REGULATORY AFFAIRS SPECIALIST 595 ANGLUM ROAD HAZELWOOD MO 63042
Re: K163042
Trade/Device Name: ChromID® Strepto B Agar Regulation Number: 21 CFR 866.2360 Regulation Name: Selective culture medium Regulatory Class: I Product Code: POZ Dated: October 28, 2016 Received: October 31, 2016
Dear Ms. Russell:
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.
1
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 -A
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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Indications for Use
510(k) Number (if known) K163042
Device Name chromID® Strepto B agar
Indications for Use (Describe)
chromID® Strepto B agar is a selective chromogenic medium that is intended to aid in the qualitative determination of Group B Streptococcus (GBS) colonization in pregnant women. This medium supports the growth of, but does not differentiate between, hemolytic GBS strains. The test is performed on 18-24 hour LIM broth enrichments of vaginal/rectal swabs obtained from pregnant women. chromID® Strepto B agar results can be interpreted after 24 hours incubation with confirmation of characteristic GBS colonies from the media.
chromID® Strepto B agar is not intended to diagnose infection nor to guide or monitor treatment for infections. chromID® Strepto B agar does not provide susceptibility results. Subculture to non-selective media should be performed as needed for susceptibility testing, chromID® Strepto B agar is intended for use by laboratory health practitioners in a clinical laboratory.
| Type of Use (Select one or both, as applicable) | |
|---|---|
| Research Use (Part 21 CFR 312, Subpart D) | |
| Compassionate Use |
|X Prescription Use (Part 21 CFR 801 Subpart D)
| | Over-The-Counter Use (21 CFR 801 Subpart C)
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SECTION 030. 510(k) SUMMARY
510(k) SUMMARY
chromID® Strepto B agar
A. 510(k) Submission Information:
| Submitter's Name: | bioMérieux, Inc. |
|---|---|
| Address: | 595 Anglum Road |
| Hazelwood, MO 63042 | |
| Contact Person: | Karen Russell |
| Staff Regulatory Affairs Specialist | |
| Phone Number: | |
| Fax Number: | 314-731-8639 |
| 314-731-8689 |
Date of Preparation: October 28, 2016
B. Device Name:
Formal/Trade Name: chromID® Strepto B agar
| Classification Name: 21 CFR 866.2360 | Selective culture medium |
|---|---|
| -------------------------------------- | -------------------------- |
Product Code POZ
Selective Culture Media Common Name:
C. Predicate Device: Modified Selective Streptococcus Agar (K881577)
D. 510(k) Summary:
Intended Use:
chromID® Strepto B agar is a selective chromogenic medium that is intended to aid in the qualitative determination of Group B Streptococcus (GBS) colonization in pregnant women. This medium supports the growth of, but does not differentiate between, hemolytic and non-hemolytic GBS strains. The test is performed on 18-24 hour LIM broth enrichments of vaginal/rectal swabs obtained from pregnant women. chromID® Strepto B agar results can be interpreted after 24 hours incubation with confirmation of characteristic GBS colonies from the media.
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chromID® Strepto B agar Traditional 510(k) Submission
chromID® Strepto B agar is not intended to diagnose infection nor to guide or monitor treatment for infections. chromID® Strepto B agar does not provide susceptibility results. Subculture to non-selective media should be performed as needed for susceptibility testing. chromID® Strepto B agar is intended for use by laboratory health practitioners in a clinical laboratory.
Indications for use:
See Intended use
Device Description:
chromID Strepto B agar consists of a nutritive base combining different peptones, chromogenic substrates and antibiotics. These components enable the screening of S. agalactiae by the spontaneous appearance of pale pink to red colonies. Most other bacterial species and yeasts do not grow on this medium or do not produce typical colonies.
Substantial Equivalence:
The similarities and differences between chromID® Strepto B agar and the predicate device are described in the following table:
| Category | Predicate Device
Acumedia Manufacturers, Inc.
Modified Selective Streptococcus Agar
K881577 | Device
bioMérieux, Inc.
chromID® Strepto B agar
K163042 |
|----------------------------------|------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Classification, and Product code | Class 1 21 CFR 866.2360
JSI | Class 1 21 CFR 866.2360
PQZ |
| Intended Use | Selective agar medium for the isolation and detection of pathogenic Streptococci. | chromID® Strepto B agar is a selective chromogenic medium that is intended to aid in the qualitative determination of Group B Streptococcus (GBS) colonization in pregnant women. This medium supports the growth of, but does not differentiate between, hemolytic and non-hemolytic GBS strains. The test is performed on 18-24 hour LIM broth enrichments of vaginal/rectal swabs obtained from pregnant women. chromID® Strepto B agar results can be interpreted after 24 hours incubation with confirmation of characteristic GBS colonies from the media. chromID® Strepto B agar is not intended to diagnose infection nor to guide or monitor treatment for infections. chromID® Strepto B agar does not provide susceptibility results. Subculture to non-selective media should be performed as needed for susceptibility testing. chromID® Strepto B agar is intended for use by laboratory health practitioners in a clinical laboratory. |
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| Category | Predicate Device
Acumedia Manufacturers, Inc.
Modified Selective Streptococcus Agar
K881577 | Device
bioMérieux, Inc.
chromID® Strepto B agar
K163042 |
|------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Test method | Manual, culture media | Manual, culture media |
| Sample Types | Direct from Specimen | Vaginal/rectal swab enriched in Lim broth |
| Interpretation
of positive
results | For the detection of Streptococci, examine
medium for growth and hemolytic
reactions (e.g. alpha-hemolysis, beta-
hemolysis, or no hemolysis) after 18 - 24
and 48 hours incubation. | For the detection of GBS, observe
bacterial growth and the appearance of
colonies.
Typical GBS colonies are pale pink to
red. |
| Quality
Control | Incubate at 35 ± 2°C. Examine for growth
after 18-24 hours. | Incubate in the dark at 35-37°C.
Examine for growth after 24 hours. QC
strains: Streptococcus agalactiae ATCC
12386 (positive control) and
Staphylococcus aureus ATCC 6538
(negative control) |
| Storage | 2 - 30°C. | 2 - 8°C |
Both the devices use a selective media for the detection of Streptococci. Their formulas and method of inoculation are similar. The differences between chromID® Strepto B agar and the predicate device are related to the storage temperature, QC method, and interpretation of results.
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Performance Characteristics:
Analytical Studies
The following analytical studies were conducted to evaluate the performance of chromID® Strepto B medium: Analytical Reactivity (Challenge), Analytical Specificity (Cross Reactivity), Incubation Time, Interference, Recovery, and Mixed Infection. All analytical performance studies demonstrated acceptable results.
Recovery Study-Two well-characterized GBS strains (ATCC 12386, hemolytic and ATCC 13813, non-hemolytic) were tested to determine the lowest CFU/ml detected on chromID Strepto B medium. For both strains, the last dilution for which visible growth with characteristic colonies was observed was 103 CFU/ml.
Analytical Reactivity (Challenge)-A challenge set of 20 GBS strains (hemolytic and non-hemolytic) was inoculated on the chromID Strepto B medium at low inoculum (10) CFU/ml). After 18, 24 and 48 hours, 12/20, 17/20 and 20/20 strains were detected on the chromID® Strepto B medium, respectively.
Analytical Specificity (Cross Reactivity)-To evaluate the analytical specificity of the chromID StreptoB medium with non-GBS organisms, 88 strains representing bacterial and fungal species potentially encountered in vaginal/rectal samples were inoculated onto chromID® Strepto B medium at high inoculum (10° CFU/ml). After 24 hours of incubation, 20/88 strains grew on the medium with 3 strains producing characteristic colonies (Streptococcus Group C, Streptococcus mitis, and Klebsiella pneumoniae (KPC)). After 48 hours, 30/88 grew on the medium and 6 strains producing characteristic colonies (Streptococcus Group C, Streptococcus mitis, Streptococcus pyogenes, Streptococcus anginosus, Staphylococcus aureus (MRSA), Lactobacillus sakei).
Mixed Infection-This study was conducted to evaluate the performance of chromID Strepto B agar in recovering GBS in the presence of high levels of non-target organisms. Seven non-target organisms were tested in the study that included strains known to produce pale pink to red colonies on chromID® Strepto B medium from the Cross Reactivity Study. For those non-target strains yielding pink to red colonies on chromID® Strepto B medium, colony features were used to distinguish GBS from non-target organisms. Two GBS strains (one hemolytic and one non-hemolytic) were incubated at approximately 10° CFU/ml with each non-target organism. At 24 hrs, both GBS strains were detected in the presence of 108 CFU/ml of non-target organism, except in the presence of Streptococcus Group C (NCTC 8546). At this concentration (10° CFU/ml), 5/7 non-target organisms gave characteristic colonies when grown on chromID® Strepto B medium. The 2 GBS strains gave characteristic colonies as expected when tested in the presence of non-target organisms diluted below 108 CFU/ml (10-10' CFU/ml) at 24 hrs. It was noted that all non-target organisms incubated with GBS either did not grow or grew as non-characteristic colonies on chromID Strepto B agar when diluted from 10-10 CFU/ml.
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Incubation Ten (10) GBS strains (hemolytic and non-hemolytic) were inoculated on the chromID® Strepto B medium at low inoculum (10 CFU/ml). The growth and the presence of characteristic colonies were evaluated every hour across a range that represented different target times: 18 hrs (16-20 hrs), 24 hrs (21-28 hrs), and 48 hrs (44-52 hrs). The number of strains showing characteristic colonies ranged between 5/10 (at 16 and 17 hours) and 10/10 from 44 hours and after. At 24 hours, 8/10 GBS strains showed characteristic colonies.
Interfering Substances No interference was observed for vaginal fluid, amniotic fluid, sperm, whole blood, concentrated buffy coat and stool. Of the 15 interfering substances tested, two (naproxen sodium and topical agent) demonstrated partial inhibition of GBS growth on chromID StreptoB medium. Use of compounds containing the active ingredients below had an inhibitory effect on GBS growth that was unrelated to chromID StreptoB medium performance: nystatin (10" Ul/ml), hydrocortisone (0.625 mg/ml), aluminum hydroxide (2.125 mg/ml)/magnesium hydroxide (2.250 mg/ml), mesalazine ( 5 mg/ml), barium sulfate (5 mg/ml), esomeprazole (1 mg/ml), loperamide (1 mg/ml), sennosides (40 mg/ml), metronidazole (25 mg/ml), lidocaine (2.5 mg/ml), econazole (7.2 mg/ml), naproxen sodium (27.5 mg/ml), nonoxynol-9 (one condom/50 ml sterile water; used at 1:1 dilution), benzalkonium chloride (1 wipe/100 ml sterile water; used at 1:1 dilution).
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Clinical Studies
Reproducibility and OC
Reproducibility and Quality Control were performed during the clinical studies. Quality Control and Reproducibility strains were subcultured to BAP each day of testing and observed for growth to ensure purity and the viability of the organism.
Reproducibility of the chromID® Strepto B agar was evaluated with 11 organisms including one non-hemolytic strain of Streptococcus agalactiae, and one Staphylococcus aureus strain. These organisms were tested at three of the trial sites. Expected results were obtained 100% of the 990 times tested.
Quality Control was performed with two quality control organisms tested at each study site by chromID Strepto B agar on each day of comparative and reproducibility testing:
Streptococcus agalactiae ATCC 12386, positive control
Staphylococcus aureus ATCC 6538 negative control
The results for chromID Strepto B agar were 100% correct for the 107 times tested.
Prospective Clinical Study
Clinical studies were conducted at three external sites with fresh clinical specimens. These studies were designed to evaluate the recovery Streptococcus agalactiae from 18-24 hour LIM broth enrichments of vaginal/rectal swab specimens (from pregnant women) by chromID Strepto B agar. Positive results were defined for chromID Strepto B agar as the growth of pale pink to red colonies. No growth or colonies presenting as other than pale pink to red in appearance were interpreted as a negative result. All colony types growing on chromID Strepto B agar were characterized using one or more of the following laboratory tests: gram stain, catalase, PYR testing, and latex agglutination. In addition, VITEK® MS was used to identify all organisms growing on chromID® Strepto B agar. For the Reference Culture Method, turbid LIM broth cultures were subcultured to CNA agar, and all suspicious colonies were screened to confirm or rule-out the presence of GBS using established laboratory methods: gram stain, catalase, PYR testing, and latex agglutination. VITEK MS was also used to confirm the identification of GBS by the Reference Method. Negative broth enriched specimens were incubated an additional 24 hours before calling samples negative by the Reference Culture Method.
A total of 681 vaginal/rectal specimens enriched in LIM broth per CDC guidelines were analyzed during the clinical trial. There were 60 isolates and 5 cultures removed due to protocol deviations.
There were 172 cultures that were positive for Group B Streptococcus (GBS) by chromID Strepto B (24 hours) and by the Reference Culture Method.
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| | | | Number Ntotal Performance | 2-sided 95% Score
CI |
|-------------|-----|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------|-------------------------|
| Sensitivity | 172 | 176 | 97.7% | [94.3 - 99.1]% |
| Specificity | 465 | રે રેણવાડી તેમ જ દૂધની ડેરી જેવી સવલતો પ્રાપ્ય થયેલી છે. આ ગામનાં પ્રાથમિક શાળા, પંચાયતઘર, આંગણવાડી તેમ જ દૂધની ડેરી જેવી સવલતો પ્રાપ્ય થયેલી છે. આ ગામનાં પ્રાથમિક શાળા, આંગ | 92.1% | [89.4 - 94.11% |
chromID 24hr vs. Reference Culture Method
Comparison of chromID® Strepto B at 24 hours to the Reference Culture Method resulted in a Sensitivity of 97.7% (95% CI: 94.3% - 99.1%) and Specificity of 92.1% (95% CI: 89.4 % - 94.1%)
At 24 hours, a total of 212 cultures were positive by chromID Strepto B and 176 were positive by the Reference Method. Of the 40 false positive cultures, four cultures that were positive for GBS by chromID Strepto B agar were confirmed as GBS positive by characteristic color, Gram staining, catalase reaction, Lancefield Group B positive latex agglutination, and VITEK® MS identification. The remaining 36 false positives demonstrated pale pink to red colored colonies that were not confirmed as GBS.
In the chromID Strepto B clinical study, the prevalence of GBS detected by the Reference Culture Method was 25.8% (176/681).
The chromID Strepto B medium is a screening agar medium based on colony coloration, thus it further requires identification of pale pink to red Streptococcus agalactiae colonies using a laboratory approved procedure. The medium also has the ability to recover both hemolytic and non-hemolytic strains of Streptococcus agalactiae. The clinical trial has shown chromID Strepto B agar to be a safe and effective when used in the clinical setting.
Conclusion
The analytical and clinical data demonstrate that chromID® Strepto B medium is substantially equivalent to the predicate device.