(189 days)
The Ez-HBT™ Helicobacter Blood Test is intended for use in the qualitative detection of 1302 in whole blood specimens, collected after the ingestion of 3C-urea. Helicobacter pylori (H. pylori) organisms colonizing the lining of the human stomach, produce urease which converts 13 C-urea into 13 CO2 and ammonia (NH4). The device is indicated as an aid in the diagnosis of H. pylori infection in symptomatic adult subjects, 18 years or older. For use by health care professionals. Administer test under a physician's supervision. Metabolic Solutions, Inc. or a qualified laboratory using Gas Isotope Ratio Mass Spectrometry or equivalent instrumentation must analyze the test samples.
Metabolic Solution's Ez-HBT Helicobacter Blood Test is based on the ability of H. pylori to produce the enzyme urease and convert urea to ammonia and carbon dioxide. By providing Helicosol (125 mg of 13C-labeled urea), the carbon dioxide produced by this reaction is carbon-13 labeled and an increase in the level of 1300 in the blood is an indication of the presence of H. pylori.
The test requires a single blood sample, collected 30 minutes after ingestion of the drug. Subsequently, this blood sample is transported to a qualified laboratory. The CO, is evolved from the blood into the headspace of the Vacutainer tube and analyzed by gas isotope ratio mass spectrometry (GIRMS) to determine the 13CO .: 12O2 ratio. A diagnosis of H. pylori infection is based on the detection of blood 13CO, being greater than a cutoff value.
Here's a breakdown of the acceptance criteria and study information for the Ez-HBT Helicobacter Blood Test, based on the provided text:
Acceptance Criteria and Device Performance
| Acceptance Criteria Category | Acceptance Criteria (Target) | Reported Device Performance |
|---|---|---|
| Overall Sensitivity | (Implicitly high) | 86.4% to 90.2% |
| Overall Specificity | (Implicitly high) | 94.5% to 96.4% |
| Overall Accuracy | (Implicitly high) | 91.0% to 93.8% |
| Safety | No device-related adverse events | 0 device-related adverse events reported in clinical study (9 total AEs, none device-related) |
| Stability (Room Temp.) | Maintain integrity | 7 days |
| Reproducibility | (Implicitly low variation) | Mean standard deviation $\leq$ 0.5 delta per mil (no more than 1 per mil for 2 SD) |
Study Information
2. Sample size used for the test set and the data provenance:
- Test Set Sample Size: 338 subjects
- Data Provenance: The subjects were enrolled at 7 monitored clinical sites around the United States. The study appears to be prospective, as it involved administering the 13C-urea solution and then collecting and analyzing samples.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- The text does not explicitly state the number of experts or their specific qualifications (e.g., "radiologist with 10 years of experience"). It mentions that the ground truth was established by "reference methods (histology and tissue urease testing)" and compared to "histology and PyloriTek independently as well as the two methods congruently." This implies that qualified personnel (e.g., pathologists for histology, lab technicians for PyloriTek) were involved in these reference methods, but specific numbers and detailed qualifications are not provided for the ground truth determination itself.
4. Adjudication method for the test set:
- The text indicates that sensitivity, specificity, and accuracy were measured against histology and PyloriTek separately and then "the two methods congruently." This suggests a form of consensus or combined ground truth.
- Indeterminate Zone: A specific adjudication method related to the device itself was implemented: an indeterminate zone of ± 0.5 per mil around the cutoff (-17.0 to -18.0) was established. Samples falling into this zone (4.7% of all samples) were excluded from sensitivity, specificity, and accuracy calculations and were recommended to be re-administered and reevaluated. This acts as an internal adjudication rule for the device's output.
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:
- No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This device is a diagnostic test (blood test analyzed by Gas Isotope Ratio Mass Spectrometry), not an imaging or interpretation aid for human readers. Therefore, there's no concept of human readers improving with or without AI assistance in this context.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Yes, the performance study described for the Ez-HBT is essentially a standalone (algorithm only) performance study. The device, after a blood sample collection, produces a quantitative result (delta 13C value) which is then compared against a cutoff for diagnosis. There is no "human-in-the-loop" influencing the immediate output of the test itself, although a physician supervises the administration and uses the test results.
7. The type of ground truth used:
- The ground truth used was a combination of expert-defined reference methods:
- Histology: Examination of tissue for the presence of H. pylori.
- Tissue Urease Testing (PyloriTek): A separate test that detects urease activity in tissue biopsies.
- The performance was evaluated against these two methods both independently and congruently.
8. The sample size for the training set:
- The term "training set" is not explicitly used for the final model. However, the determination and refinement of the cutoff point used two phases of data:
- Initial determination of cutoff: 115 asymptomatic controls + 121 adult subjects with dyspeptic symptoms (total 236 subjects).
- Refinement of cutoff: 338 subjects (the same set used for the main clinical study).
- It's reasonable to infer that these datasets were used to "train" or establish the diagnostic cutoff values for the device.
9. How the ground truth for the training set was established:
- For the 115 asymptomatic controls: The ground truth for H. pylori negativity would have been based on clinical assessment and likely the absence of H. pylori according to other established methods (though not explicitly detailed beyond "asymptomatic controls").
- For the 121 adult subjects with dyspeptic symptoms: The ground truth for H. pylori infection was established by "reference methods (histology and tissue urease testing)."
- For the 338 subjects in the cutoff refinement and clinical study: The ground truth was similarly established using "histology and PyloriTek independently as well as the two methods congruently."
§ 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).