K994101 · Techlab, Inc. · KHW · Dec 21, 1999 · Microbiology
Device Facts
Record ID
K994101
Device Name
E. HISTOLYTICA II
Applicant
Techlab, Inc.
Product Code
KHW · Microbiology
Decision Date
Dec 21, 1999
Decision
SESE
Submission Type
Special
Regulation
21 CFR 866.3220
Device Class
Class 2
Attributes
Pediatric
Indications for Use
The E. histolytica II is an enzyme immunoassay for the rapid detection of the adhesin of E. histolytica in human fecal specimens. It is indicated for use with fecal specimens from patients with diarrhea or dysentery to determine the presence of E. histolytica gastrointestinal infection. The test can be used for fecal specimens submitted for routine clinical testing from adults or children. Conventional microscopy is not a routine prerequisite for use of the test. FOR IN VITRO DIAGNOSTIC USE.
Device Story
E. histolytica II is an ELISA-based in vitro diagnostic test for detecting E. histolytica adhesin (galactose-inhibitable lectin) in human stool. The device utilizes microtiter wells coated with polyclonal goat antibodies to capture the adhesin, followed by a monoclonal mouse antibody conjugate for detection. The test is performed in clinical laboratories as a rapid, sensitive alternative to time-consuming culture and zymodeme analysis. By specifically identifying pathogenic E. histolytica without cross-reacting with nonpathogenic E. dispar, the device assists clinicians in diagnosing amebiasis. Results are interpreted by laboratory personnel to guide clinical management of patients presenting with diarrheal symptoms.
Clinical Evidence
Clinical evaluation compared E. histolytica II results against zymodeme analysis of cultured Entamoeba isolates and the predicate E. histolytica TEST. Study demonstrated >97% correlation with zymodeme analysis. The device showed higher sensitivity than the predicate for detecting E. histolytica trophozoites and adhesin in stool specimens from endemic areas.
Technological Characteristics
ELISA-based immunoassay. Components: microtiter wells coated with polyclonal goat antibody, monoclonal mouse antibody conjugate, positive control, diluent, substrate, wash solution, and stop solution. Standalone diagnostic kit for laboratory use.
Indications for Use
Indicated for adults and children with diarrhea or dysentery to detect E. histolytica adhesin in fecal specimens to diagnose gastrointestinal infection.
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.
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12/21/99 K994101
SUMMARY OF SAFETY AND EFFECTIVENESS (**E. histolytica II**)
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#### 1. Name of Manufacturer
TechLab. Inc. Corporate Research Center 1861 Pratt Drive, STE 1030 Blacksburg, VA 24060-6364
# 2. Establishment Registration
Federal ID # 54-1527427 Initial Registration of Medical Device Establishment, #1122855
## 3. Trade Name
- E. histolytica II
## 4. Common Name
E. histolytica ELISA
# 5. Class of Device
This device is classified in Class II.
# 6. Performance Standards
No performance standards have been developed for this device under 514 of the Food, Drug, and Cosmetic Act.
# 7. Safety and Effectiveness
The E. histolytica II can be used to detect adhesin (also referred to as galactose-inhibitable lectin) produced by strains of E. histolytica. It does not cross-react with the adhesin from E. dispar (formerly known as nonpathogenic E. histolytica). The test can be used to detect the adlaesip in fest specimens from persons suspected of having amebiasis. The kit, which includes ready-to-use reagents, contains microtiter wells coated with polycloual antibody, positive control reagent, monclonal-antibody conjugate, diluent, one component substrate, wash solution, and stop solution, The microtiter wells coated with polyclonal antibody "capture" the adhesin and the monoclonal anthologyconjugate serves as the "detecting" antibody. The polyclonal antibody used to monthcound is prepared from hyperimmune antiserum developed in goats. The monoclonal antibody wedia prepare the conjugate is prepared from mouse ascites fluid
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#### SUMMARY OF SAFETY AND EFFECTIVENESS (E. histolytica II) (cont'd)
The E. histolytica II is to be used in an ELISA format and is substantially equivalent to culturing and zymodeme analysis that are used in some clinical laboratories as diagnostic aids. It also is more sensitive than our E. histolytica TEST (K955895), which has been cleared previously for in vitro diagnostic use. Culturing is used to obtain the isolate and zymodeme analysis is used to examine the enzyme profile of the isolate. Zymodeme analysis must be used to determine if the isolated Entamoeba strain is pathogenic. The major disadvantages are that culturing and zymodeme are timeconsuming and labor-intensive. Only a few clinical laboratories around the world are capable of performing this type of analysis. The E. histolytica II offers a major advantage to clinical laboratories because it is rapid, easy-to-perform, and it is more sensitive than our E. histolytica TEST, which was the first test to offer clinical labs a simpler and easier alternative format than zymodeme analysis for the specific detection of pathogenic E. histolytica. Like the E. histolytica TEST, the E. histolytica II is highly specific for pathogenic Entamoe a
The E. histolytica II is different from TechLab's Entumoeba TEST and the Alexon ProSpecT Entamoeba histolytica Test. These two tests detect both E. histolytica (formerly referred to as pathogenic E. histolytica) and E. dispar (formerly referred to as nonpathogenic E. histolytica). They do not distinguish between E. histolytica and E. dispar. The E. histolytica II is very similar to TechLab's E. histolytica TEST. Both are highly specific for the adhesin of E. histolytica and neither cross-reacts with the adhesin of E. dispar. Both have the same procedure and utilize an ELISA format. The difference between the E. histolytica II and the E. histolytica TEST is that the E. histolytica II offers increased sensitivity. Although all of these tests serve as diagnostic aids for amebiasis, the E. histolytica II is specific for pathogenic strains and offers higher sensitivity.
The E. histolytica II was used to analyze stool specimens in areas where amebiasis is endemic, and the results were compared with zymodeme analysis of Entamoeba isolates cultured from these specimens and with the E. histolytica TEST. It is important to remember that culture, without the aid of zymodeme analysis, does not distinguish between E. dispar. Zymodeme analysis, which is available only in a sclect number of clinical laboratories around the world, is the only method that distinguishes these species. For the purpose of our studies, zymodeme analysis represents the "gold standard". The results of our clinical evaluations show that the E. histolvica II exhibits a correlation of >97% when compared with zymodeme analysis, and that it is more sensitive than the E. histolytica Test for detecting E. histolytica trophozoites and adhesin. Our findings demonstrate that the test is useful for the detection of pathogenic E. histolytica in stool specimens.
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Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized depiction of an eagle with three curved lines representing its wings. The eagle is positioned above the acronym "HHS". The text "OF HEALTH & HUMAN SERVICES - USA" is arranged in a semi-circle above the eagle.
Food and Drug Administration 2098 Gaither Road Rockville MD 20850
DEC 2 1 1999
David M. Lyerly, Ph.D. Vice President TechLab. Inc. VPI Research Park 1861 Pratt Drive, Suite 1030 Blacksburg, Virginia 24060-6364
Re: K994101 Trade Name: E. histolytica II Regulatory Class: II Product Code: KHW Dated: November 22, 1999 Received: December 6, 1999
#### Dear Dr. Lyerly:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we 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). 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.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will veify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Eederal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal Javs or regulations.
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Page 2
Under the Clinical Laboratory Improvement Amendments of 1988 (CLIA-88), this device may require a CLIA complexity categorization. To determine if it does, you should contact the Centers for Disease Control and Prevention (CDC) at (770)488-7655.
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4588. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its to lifee number (800) 638-2041 or at (301) 443-6597 or at its internet address "http://www.fda.gov/cdrh/dsmamain.html"
Sincerely yours,
Steven Autman
Steven I. Gutman, M.D., M.B.A. Director Division of Clinical Laboratory Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
2
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K 494101
Page__________________________________________________________________________________________________________________________________________________________________________
510(k) Number (if known):_____________________________________________________________________________________________________________________________________________________ E. histolytica II
Device Name:_
Indications For Use:
The E. histolytica II is an enzyme immunoassay for the rapid detection of the adhesin of E. histolytica in human fecal specimens. It is indicated for use with fecal
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routine prerequisite for use of the test. FOR IN VITRO DIAGNOSTIC USE.
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| Concurrence of CDRH, Office of Device Evaluation (ODE) | | |
|--------------------------------------------------------|---------|--------------------------|
| Wordy Dators | | |
| (Division Sign/Off) | | |
| Division of Clinical Laboratory Devices | | |
| 510(k) Number | K994101 | |
| Prescription Use | OR | Over-The-Counter Use |
| (Per 21 CFR 801.109) | | (Optional Format 1-2-96) |
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