GIARDIA FECAL ANTIGEN DETECTION LATERAL FLOW KIT, MODEL GL-LF
K081064 · Ivd Research, Inc. · MHI · Jan 14, 2009 · Microbiology
Device Facts
Record ID
K081064
Device Name
GIARDIA FECAL ANTIGEN DETECTION LATERAL FLOW KIT, MODEL GL-LF
Applicant
Ivd Research, Inc.
Product Code
MHI · Microbiology
Decision Date
Jan 14, 2009
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 866.3220
Device Class
Class 2
Attributes
Real-World Evidence
Real-World Evidence
Submission
Device
Sponsor
RWD Sources
RWE Use Summary
Key Tags
K081064 · Jan 14, 2009
GIARDIA FECAL ANTIGEN DETECTION LATERAL FLOW KIT, MODEL GL-LF
Ivd Research, Inc.
Archived human fecal specimens; Independent laboratory clinical testing records
Retrospective clinical performance evaluation using 210 archived human fecal specimens to determine sensitivity and specificity compared to microscopy or direct immunofluorescence assay.
Sensitivity and Specificity Compared to Microscopy or Direct Immunofluorescence Assay; Retrospective study using archived samples
Human fecal specimens; Sample Size: 210; Number of Sites: 1 (independent laboratory)
Microscopy or direct immunofluorescence assay
Sensitivity and specificity
Indications for Use
The IVD Research, Inc. Giardia Fecal Antigen Detection Lateral Flow Kit is a qualitative immunoassay for the detection of Giardia antigens in preserved and unpreserved human fecal specimens. This test is indicated as an aid in the clinical laboratory diagnosis of suspected Giardia infections.
Device Story
Lateral flow immunoassay for detection of Giardia antigens in human fecal specimens. Sample mixed with buffer, dispensed into device sample well, and wicked along nitrocellulose membrane. Membrane contains bound rabbit anti-Giardia and goat-anti-mouse antibodies. Giardia antigen, if present, forms immune complex with gold colloidal-labeled antibodies, producing visible pink-to-purple test line. Control line confirms valid test. Used in clinical laboratories by trained personnel. Provides qualitative visual result to assist clinicians in diagnosing Giardia infections, facilitating timely patient management.
Clinical Evidence
Clinical study compared 210 preserved stool samples against microscopy. Sensitivity: 97.2% (95% CI: 92.2-99.4%); Specificity: 96% (95% CI: 90.2-98.9%). Discrepant analysis using direct immunofluorescence confirmed false positives were actually positive. Analytical sensitivity (LOD) is 20 ng/mL. No cross-reactivity observed with 40+ common enteric pathogens/microorganisms. No interference from blood, mucin, or Imodium.
Technological Characteristics
Qualitative immunochromatographic lateral flow assay. Components: Mylar-backed nitrocellulose membrane, colloidal gold-labeled mouse monoclonal anti-Giardia antibody conjugate, rabbit anti-Giardia capture antibody, goat anti-mouse IgG control line antibody. Form factor: lateral flow test strip in cassette. Standalone device; no energy source required. Manual operation.
Indications for Use
Indicated for the qualitative detection of Giardia antigens in preserved and unpreserved human fecal specimens as an aid in the clinical laboratory diagnosis of suspected Giardia infections. For in vitro diagnostic use.
Regulatory Classification
Identification
Entamoeba histolytica serological reagents are devices that consist of antigens and antisera used in serological tests to identify antibodies to Entamoeba histolytica in serum. Additionally, some of these reagents consist of antisera conjugated with a fluorescent dye (immunofluorescent reagents) used to identify Entamoeba histolytica directly from clinical specimens. The identification aids in the diagnosis of amebiasis caused by the microscopic protozoan parasite Entamoeba histolytica and provides epidemiological information on diseases caused by this parasite. The parasite may invade the skin, liver, intestines, lungs, and diaphragm, causing disease conditions such as indolent ulcers, an amebic hepatitis, amebic dysentery, and pulmonary lesions.
Special Controls
*Classification.* Class II (special controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 866.9.
{0}
1
# 510(k) SUBSTANTIAL EQUIVALENCE DETERMINATION DECISION SUMMARY ASSAY ONLY TEMPLATE
A. 510(k) Number:
K 081064
B. Purpose for Submission:
To determine substantial equivalence of the device for the detection of Giardia antigens in human fecal specimens.
C. Measurand:
Giardia fecal antigen
D. Type of Test:
Qualitative immunoassay
E. Applicant:
IVD Research Inc.
F. Proprietary and Established Names:
Giardia Fecal Antigen Detection Lateral Flow Kit
G. Regulatory Information:
| Product Code | Classification | Regulation Section | Panel |
| --- | --- | --- | --- |
| MHI | Class II | 21 CFR 866.3220 | 83 Microbiology |
H. Intended Use:
1. Intended use:
The Giardia Fecal Antigen Detection Lateral Flow Kit is an in vitro qualitative immunoassay for the detection of Giardia antigens in preserved and unpreserved fecal specimens. This test is indicated as an aid in the clinical laboratory diagnosis of suspected Giardia infections
{1}
2. Indications for use:
The IVD Research Inc. Giardia Fecal Antigen Detection Lateral Flow Kit is a qualitative immunoassay for the detection of Giardia antigens in preserved and unpreserved fecal specimens. This test is indicated as an aid in the clinical laboratory diagnosis of suspected Giardia infections.
For in vitro diagnostic use.
3. Special conditions for use statement:
For prescription use
4. Special instrument requirements:
None
I. Device Description:
The kit contains 20 individually packaged test devices comprised of a nitrocellulose membrane to which rabbit anti-Giardia and goat-anti-mouse antibodies have been bound. The membrane is assembled with a cellulose fiber pad to form the test strip, which is then placed into a plastic housing and sealed. The housing contains a sample window, where the diluted fecal sample is added and a test window where the test result is read. The kit also contains Dilution Buffer A consisting of 6 ml of a buffer and 0.095% sodium azide as a preservative; dilution Buffer B consisting of 6 ml of a buffered 10% formalin solution for diluting fresh or frozen samples; disposable transfer pipets and sample dilution tubes for 20 tests and directions for use. The kit must be stored at 2- 30°C.
J. Substantial Equivalence Information:
The predicate device is Xpect Giardia Lateral Flow Assay (K031942). The new device and predicate are similar in Intended Use, type of technology, use the same Giardia specific monoclonal antibodies and show similar clinical performance. They differ in sample volume and the predicate conjugate has mouse IgG and utilizes a colored polystyrene bead whereas the new device uses a gold colloidal label.
K. Standard/Guidance Document Referenced (if applicable):
N/A
L. Test Principle:
The Giardia Fecal Antigen Detection lateral flow device uses sample wicking to capture Giardia antigen on a discrete test line which contains antibodies specific for
2
{2}
the Giardia antigen. A fecal specimen is added to a dilution tube and mixed with buffer solution. The mixture is dispensed into the sample well of the device and wicks along the membrane containing capture antibodies bound to the membrane at the test and control lines. The Giardia immune complex, if present, reacts with anti-Giardia antibody at the test line. Unbound conjugate not captured at the test line is captured at the control line containing anti mouse antibody. If Giardia antigens are present in the fecal sample, two pink-to-purple bands will appear in the Test Window – one at the sample line and one at the control line. If no Giardia antigen is present or the level is below the detection limit of the assay, only one pink-to-purple band will appear at the control line. For the test to be valid, there must always be a pink-to-purple line band at the control line.
## M. Performance Characteristics:
### 1. Analytical performance:
a. Reproducibility:
A total of 4 negative, 3 low positive and 3 positive samples, along with positive and negative controls, were run at three separate sites once a day for 3 days. Visual interpretation was similar at all locations and runs. The inter-assay correlation was 100% between the three sites.
b. Linearity/assay reportable range:
N/A
c. Traceability, Stability, Expected values (controls, calibrators, or methods):
N/A
d. Detection limit:
The analytical sensitivity of the device was determined by diluting cultured Giardia lamblia (WB strain) in negative human stool and testing across an antigen concentration range of 2.5 ng/mL to 80 ng/mL. Test results determined the limit of detection for the device as 20 ng/ml.
e. Analytical specificity:
### Cross-reactivity
No cross-reactions were seen with the following organisms:
Entamoeba hartmanni, Endolimax nana, Entamoeba histolytica/dispar, Entamoeba coli, Blastocystis hominis, Dientamoeba fragilis, Chilomastix
{3}
mesnili, Cyclospora cayetanensis, Strongyloides stercoralis, Cryptosporidium, Ascaris lumbricoides, Enterobius vermicularis, Diphyllobothrium species, Hymenolepis nana, Clonorchis sinensis, Enteromonas hominis, Trichuris trichiura, Iodamoeba buetschlii, Schistosoma mansoni, rotavirus, Taenia eggs, Fasciola eggs, Isospora belli, adenovirus, rotavirus, Salmonella typhimurium, Proteus vulgaris, E. coli 43887, Campylobacter coli, Salmonella enteritidis, Campylobacter fetus, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Serratia liquefaciens, Enterobacter cloacae, Citrobacter braakii, Shigella flexneri, Shigella dysenteria, E. hermannii, Campylobacter jejuni, Salmonella infantis, Yersinia enterocolitica, Enterococcus faecalis and Helicobacter cinaedi. Additionally, six common microorganisms (Campylobacter coli, E. coli, Salmonella enteritidis, Shigella flexneri, Campylobacter jejuni, and Yersinia enterocolitica) spiked into preserved positive and negative fecal specimens did not affect the test result.
## Interfering Substances
Human feces samples positive and negative for Giardia antigen were spiked with blood, mucin, or Imodium® prior to testing with the Giardia Fecal Antigen Detection Lateral Flow Kit. Testing indicated that none of these substances interfered with the test.
f. Assay cut-off:
N/A
2. Comparison studies:
a. Method comparison with predicate device:
One hundred and ten fecal specimens were tested with the Giardia fecal antigen detection lateral flow kit and the predicate device. Results were as follows:
Positive Agreement 98% (48/49)
Negative Agreement 100% (61/61)
b. Matrix comparison:
N/A
3. Clinical studies:
a. Clinical Sensitivity:
{4}
A total of 210 formalin or SAF preserved stools were tested with the Giardia LF test and the results were compared to microscopy. Results were as follows:
Sensitivity: 97.2% (106/109) 95% CI = 92.2% to 99.4%
Specificity: 96% (97/101) 95% CI = 90.2% to 98.9%
Four “negative” specimens gave a false positive result when tested with the Giardia LF test. These discrepant samples were re-tested using a direct immunofluorescence assay and shown to be positive.
b. Clinical specificity:
Refer to (a) above
c. Other clinical supportive data (when a. and b. are not applicable):
N/A
4. Clinical cut-off:
N/A
5. Expected values/Reference range:
Normal healthy individuals should be free of Giardia and should test negative. A positive reaction indicates that the patient is shedding detectable amounts of Giardia antigen. Certain populations, such as children in day care settings, have shown higher rates of infection with Giardia than the normal population. Typical prevalence rates for Giardia in developed countries have been reported to be 2-5%.
N. Proposed Labeling:
The labeling is sufficient and it satisfies the requirements of 21 CFR Part 809.10.
O. Conclusion:
1. The information submitted in this premarket notification is complete and supports a substantial equivalence decision.
Predicate graph will load when search results are available.
Embedding visualization will load when search results are available.
PDF viewer will load when search results are available.
Loading panels...
Select an item from Submissions
Click any panel, subpart, regulation, product code, or device to see details here.
Section Matches
Results will appear here.
Product Code Matches
Results will appear here.
Special Control Matches
Results will appear here.
Loading collections...
Loading
My Alerts
You will receive email notifications based on the filters and frequency you set for each alert.
Sort by:
Create Alert
Search Filters
Agent Token
Create a read-only bearer token for Claude, ChatGPT, or other agents that can call HTTP APIs.
Copy this now. It will not be shown again.
Connected apps
Apps you authorized through browser sign-in. Disconnecting revokes their access immediately.
Learn the FDA Browser
Two short videos show you everything — or skip straight to the written tutorial if you'd rather read. You can reopen this any time from the Tutorial button in the top bar.
Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
Use the checkboxes above the results to narrow: SaMD keeps only software-only devices, AI / ML keeps only devices with AI.
Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
Where do you find a device's intended use without opening the PDF?
Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
6. Collections
With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
How do you save a set of selected devices for later use?
Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.
