(132 days)
The Wampole Pylori IgG ELISA assay may be used as an aid in the diagnosis of Helicobacter pylori infection in persons with gastrointestinal symptoms. For In Vitro Diagnostic Use Only.
The Pylori IgG ELISA kit is an Enzyme-Linked Immunosorbent Assays (ELISA) for the qualitative determination of IgG antibodies in human serum to Helicobacter pylori antigen. The Pylori IgG ELISA test is an enzyme linked immunosorbent assay to detect IgG antibodies to Helicobacter pylori. Purified Helicobacter pylori antigen is attached to a solid phase microtiter well. Diluted test sera is added to each well. If the antibodies are present that recognize the antigen, they will bind to the antigen in the well. After incubation the wells are washed to remove unbound antibody. An enzyme labeled antihuman IgG is added to each well. If antibody is present it will bind to the antibody attached to the antigen on the well. After incubation the wells are washed to remove unbound conjugate. A substrate solution is added to each well. If enzyme is present the substrate will undergo a color change. After an incubation period the reaction is stopped and the color intensity is measured photometrically, producing an indirect measurement of specific antibody in the patient specimen.
Here's an analysis of the provided information, structured according to your request:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state "acceptance criteria" as a set of predefined thresholds. Instead, it presents the performance characteristics of the Pylori IgG ELISA and the previously evaluated Pylori Stat, with the underlying implication that the Pylori IgG ELISA's performance is deemed acceptable relative to the Pylori Stat and biopsy.
Based on the provided data, we can infer the achieved performance:
| Performance Metric | Pylori IgG ELISA (Reported) | Pylori Stat (for comparison) |
|---|---|---|
| Sensitivity | 96.4% (95% CI: 94.1%-98.8%) | 98.5% (95% CI: 97.0%-100%) |
| Specificity | 96.1% (95% CI: 92.3%-99.9%) | 98.1% (95% CI: 95.5%-100%) |
| Agreement | 96.4% (95% CI: 94.4%-98.3%) | 98.4% (95% CI: 97.1%-99.7%) |
| Precision (CV - range for interassay) | 6.06% - 38.8% (for different sera) | (Not provided for direct comparison) |
2. Sample Size Used for the Test Set and Data Provenance
- Pylori IgG ELISA Test Set Sample Size: 371 serum samples
- Pylori Stat (predicate device) Test Set Sample Size: 386 serum samples
- Data Provenance (Both devices):
- Country of Origin: Not explicitly stated, but mentioned as "five geographically different areas."
- Retrospective or Prospective: Not explicitly stated. However, the use of "serum from patients" and existing biopsy results suggests a retrospective analysis of collected samples.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
This information is not provided in the document. The ground truth was established by "biopsy with stain or culture results for H. pylori." The number of pathologists/microbiologists interpreting these biopsies and their qualifications are not mentioned.
4. Adjudication Method for the Test Set
This information is not provided in the document. It only states that equivocal results were not included in the sensitivity and specificity calculations.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, If So, What Was the Effect Size of How Much Human Readers Improve with AI vs without AI Assistance
This is not applicable. The device is an immunoassay (ELISA kit) for detecting antibodies, not an AI-powered diagnostic tool that assists human readers. Therefore, an MRMC study related to AI assistance is not relevant to this submission.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Yes, a standalone performance evaluation of the Pylori IgG ELISA was done. The device directly produces results (qualitative determination of IgG antibodies), and its performance metrics (sensitivity, specificity, agreement) were calculated independently against the biopsy ground truth. This is the inherent nature of an ELISA test.
7. The Type of Ground Truth Used
The ground truth used for performance evaluation was: Biopsy with stain or culture results for H. pylori. This combines histological and microbiological evidence.
8. The Sample Size for the Training Set
This information is not provided. The document describes the evaluation of the Pylori IgG ELISA and its predicate, Pylori Stat, which implies they are already developed products. There is no mention of a "training set" in the context of developing the ELISA assay, as it's a biochemical test, not a machine learning algorithm.
9. How the Ground Truth for the Training Set Was Established
This information is not applicable/provided for the reasons stated in point 8.
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JUL 30 1996
Summary of Safety and Effectiveness Information Pylori IgG ELISA Test Kit
- I. Immuno Probe Inc. 1306 Bailes Lane, Suite F Frederick, Maryland 21701 Contact person: William Boteler Telephone: 301-695-7920 Date of preparation: March 28,1995
- II. Description of Device
The Pylori IgG ELISA kit is an Enzyme-Linked Immunosorbent Assays (ELISA) for the qualitative determination of IgG antibodies in human serum to Helicobacter pylori antigen. The Wampole Pylori IgG ELISA assay may be used as an aid in the diagnosis of Helicobacter pylori infection in persons with gastrointestinal symptoms. For In Vitro Diagnostic Use Only.
The Pylori IgG ELISA test is an enzyme linked immunosorbent assay to detect IgG antibodies to Helicobacter pylori. Purified Helicobacter pylori antigen is attached to a solid phase microtiter well. Diluted test sera is added to each well. If the antibodies are present that recognize the antigen, they will bind to the antigen in the well. After incubation the wells are washed to remove unbound antibody. An enzyme labeled antihuman IgG is added to each well. If antibody is present it will bind to the antibody attached to the antigen on the well. After incubation the wells are washed to remove unbound conjugate. A substrate solution is added to each well. If enzyme is present the substrate will undergo a color change. After an incubation period the reaction is stopped and the color intensity is measured photometrically, producing an indirect measurement of specific antibody in the patient specimen.
- III. Predicate Device
The Pylori IgG ELISA test is substantially equivalent to biopsy. Equivalence is demonstrated by the following comparative results.
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Performance Characteristics
A. Evaluation of Pylori IgG ELISA Sensitivity and Specificity Relative to Biopsy
The Pylori IgG ELISA is a modification of Pylori Stat. Pylori Stat was originally evaluated by masked testing 386 serum from five geographically different areas, with biopsy with stain or culture results for H. pylori. The serum were from patients with random gender and various ages with the following clinical diagnosis: gastric ulcer, duodenal ulcer, non-ulcer dyspepsia, esophagitis and normal. Table 1 illustrates the sensitivity and specificity of Pylori Stat to Biopsy.
| Pylori Stat | |||||
|---|---|---|---|---|---|
| + | eq | - | Total | ||
| Biopsy* | + | 261 | 12 | 4 | 277 |
| - | 2 | 2 | 105 | 109 | |
| Total | 263 | 14 | 109 | 386 |
Table 1 Pylori Stat IgG ELISA Sensitivity and Specificity
| Sensitivity = 261/265 = 98.5% | 95% Confidence interval = 97.0% - 100% |
|---|---|
| Specificity = 105/107 = 98.1% | 95% Confidence interval = 95.5% - 100% |
| Agreement = 366/372 = 98.4% | 95% Confidence interval = 97.1% - 99.7% |
- Culture or stain
Equivocals were not included in the above calculations.
The 95% confidence intervals were calculated using the normal method.
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The Pylori IgG ELISA was evaluated by masked testing 371 serum from five geographically different areas, with biopsy with stain or culture results for H. pylori. The serum were from patients with random gender and various ages with the following clinical diagnosis: gastritis, gastric ulcer, duodenal ulcer, non-ulcer dyspepsia, esophagitis and normal. Table 2 illustrates the sensitivity and specificity of Pylori IgG ELISA to Biopsy.
Table 2
Pylori IgG ELISA Relative Sensitivity and Specificity
Wampole Pylori IgG ELISA
| + | eq | - | Total | ||
|---|---|---|---|---|---|
| + | 244 | 13 | 9 | 266 | |
| Biopsy* | - | 4 | 2 | 99 | 105 |
| Total | 248 | 15 | 108 | 371 |
| Sensitivity = 244/253 = 96.4% | 95% Confidence interval = 94.1% - 98.8% |
|---|---|
| Specificity = 99/103 = 96.1% | 95% Confidence interval = 92.3% - 99.9% |
| Agreement = 343/356 = 96.4% | 95% Confidence interval = 94.4% - 98.3% |
- Culture or stain positive
Equivocals were not included in the above calculations.
The 95% confidence intervals were calculated using the normal method.
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B. Evaluation of Pylori IgG ELISA Precision
The precision of the Pylori IgG ELISA was determined by testing six different sera ten times each on three days. The mean coefficients of variation from the intra- and interassays are presented in Table 3
Table 3 Pylori IgG ELISA Precision
| Assay 1 (n=10) | Assay 2 (n=10) | Assay 3 (n=10) | InterAssay (n=30) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| X | SD | CV | X | SD | CV | X | SD | CV | X | SD | CV | |
| 1 | 3.13 | 0.209 | 6.68% | 3.05 | 0.145 | 4.75% | 3.13 | 0.210 | 6.71% | 3.10 | 0.188 | 6.06% |
| 2 | 2.08 | 0.151 | 7.26% | 2.15 | 0.156 | 7.26% | 2.01 | 0.127 | 6.32% | 2.08 | 0.151 | 7.26% |
| 3 | 2.31 | 0.258 | 11.2% | 2.29 | 0.115 | 5.02% | 2.24 | 0.173 | 7.72% | 2.28 | 0.187 | 8.20% |
| 4 | 1.17 | 0.184 | 15.7% | 1.47 | 0.148 | 10.1% | 1.30 | 0.179 | 13.8% | 1.31 | 0.207 | 15.8% |
| 5 | 0.06 | 0.018 | 30.0% | 0.12 | 0.014 | 11.7% | 0.11 | 0.056 | 50.9% | 0.08 | 0.031 | 38.8% |
| 6 | 0.10 | 0.016 | 16.0% | 0.14 | 0.020 | 14.3% | 0.10 | 0.067 | 67.0% | 0.12 | 0.023 | 19.2% |
C. Evaluation of Pylori IgG ELISA with Potentially Cross Reactive Sera.
Pylori IgG ISR values were determined for paired sera from C. jujuni infections and single sera from C fetus infections. The data in Table 4 shows no rise in antibody for C. jujuni paired sera, and negative responses for C fetus infections indicating a lack of cross reactivity to these closely related organisms. Serum pairs 1, 3 and 4 demonstrate antibody to H. pylori. The pairs do not show as rise in antibody as would be expected in acute C. jujuni infection, therefore the response is considered to be specific for H. pylori with no cross reaction with C. jujuni. Sera positive for antibodies to Borrelia burgdorferi by ELISA and Western Blot were negative indicating a lack of cross reactivity.
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Table 4 Pylori IgG Results with Potentially Cross-reactive Sera
| Serum # | Diagnosis* | Pylori IgG ISE |
|---|---|---|
| Acute 1Convalescent 1 | C. jejuni Diarrhea | 2.302.41 |
| Acute 2Convalescent 2 | C. jejuni Diarrhea | 2.112.23 |
| Acute 3Convalescent 3 | C. jejuni Diarrhea | 1.231.20 |
| Acute 4Convalescent 4 | C. jejuni Diarrhea | 0.400.57 |
| Acute 5Convalescent 5 | C. jejuni Diarrhea | 0.880.89 |
| 6 | C. fetus Endocarditis | 0.59 |
| 7 | C. fetus Endocarditis | 0.63 |
| 8 | C. fetus Endocarditis | 0.72 |
| 9 | C. fetus Bacteremia | 0.38 |
- All cases diagnosed by culture, C. jejuni infection by fecal culture on Camplylobacterspecific media, C_ fetus infection by blood culture.
| 10. | Borrelia burgdorferi | 0.44 |
|---|---|---|
| 11. | Borrelia burgdorferi | 0.20 |
| 12. | Borrelia burgdorferi | 0.22 |
| 13. | Borrelia burgdorferi | 0.89 |
| 14. | Borrelia burgdorferi | 0.11 |
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| 15. | Borrelia burgdorferi | 0.20 |
|---|---|---|
| 16. | Borrelia burgdorferi | 0.16 |
| 17. | Borrelia burgdorferi | 0.59 |
| 18. | Borrelia burgdorferi | 0.09 |
| 19. | Borrelia burgdorferi | 0.13 |
All Borrelia burgdorferi sera were positive for antibodies by ELISA and Western Blot. Their clinical histories were suggestive of Lyme Disease
:
§ 866.3110
Campylobacter fetus serological reagents.(a)
Identification. Campylobacter fetus serological reagents are devices that consist of antisera conjugated with a fluorescent dye used to identifyCampylobacter fetus from clinical specimens or cultured isolates derived from clinical specimens. The identification aids in the diagnosis of diseases caused by this bacterium and provides epidemiological information on these diseases.Campylobacter fetus is a frequent cause of abortion in sheep and cattle and is sometimes responsible for endocarditis (inflammation of certain membranes of the heart) and enteritis (inflammation of the intestines) in humans.(b)
Classification. Class I (general controls).