Controls

One of the most important features of the PyloriTek® test strip is that every test strip has a built in positive and negative control. Controls are built into each test strip to show that:

• The procedure has been followed correctly.
• The test strip has not been improperly stored or handled.

Unlike gel- or liquid-based rapid urease tests, the PyloriTek® user does not have to do any extra steps to run a positive and negative control. The positive control spot on a fresh PyloriTek® strip is a dried urease which is visible as a red spot. The positive control must turn dark purple or blue on every strip for the test to be valid. The negative control is any area of the yellow membrane where there is no biopsy specimen or control spot. It is recommended that the user should select a specific area of the test strip to be the negative control area. For example, the upper right hand corner is a convenient location. Never put a specimen in this area. The negative control area should remain yellow. Except for blue or purple color or light blue or gray shadows directly above the biopsy specimen or positive control, the yellow area should always remain unchanged in color. If the entire yellow area of the test strip turns a solid or patchy blue, open a new bottle of test strips and repeat the test. This blue patchy color will only appear if the PyloriTek® strips are left out of the bottle for several days or exposed to ammonia fumes. Possible sources of ammonia are smelling salts and cleaning liquids which often contain ammonia. If the positive control does not appear at the end of 60 minutes (1 hour), immediately remove the biopsy and transfer to a fresh test strip and repeat the test.

Possible causes of the positive control not developing may include:

• The user forgot to apply Hydration Reagent or added it too soon (always be sure the substrate pad is wet before closing the strip).
• The strip was not folded properly or was not inserted into the reaction chamber properly. (Do not use tape or paper clips to hold the folded strip. Always fold the strip at the perforation to assure proper pad alignment.)
• The positive control spot can be rubbed off with pressure from a wet latex glove. Do not touch the control spot while preparing the strip.

Remember: always place the strip in the reaction chamber on a counter at room temperature. DO NOT remove the strip or open the strip until after the 60-minute final reading or a confirmed positive result.

• Always store unopened PyloriTek® kits in a refrigerator.
• Do not put an opened kit back into the refrigerator.
• Opened kits should be stored at room temperature and in a dry area, away from direct sunlight or heat sources.
• Always replace the bottle cap immediately after removing a PyloriTek test strip.
• Always lay the test strip on clean tray or surface.

DO NOT put the strip and reaction chamber in your pocket as it contains potentially infectious biopsy material.

PyloriTek has several distinct advantages over other rapid urease tests using gel- or liquid- reaction media. The patented PyloriTek method allows the urea/urease and ammonia/pH paper reactions to take place in separate, optimal environments. Unlike competitive gel-based tests, the final result is available in 1 hour allowing for discussion of the results with the patient before he/she leaves. Most positives appear in 15 minutes or less. Unlike the competition, where the negative control cannot be run simultaneously with the patient's specimen, PyloriTek has a negative control with every strip. The only way a positive control can be run with the competitive tests is by waiting 24 hours and inserting a urease positive pellet. The PyloriTek positive control automatically appears with every test within the normal 1-hour time with NO extra steps or special materials needed.

Some investigators have reported that, due to the patchy distribution of H. pylori in the stomach, 2 or 3 biopsies from several areas of the stomach can increase chances of finding infection. If you choose to take extra biopsies, up to 3 specimens from the same patient can be placed on a single PyloriTek strip with separate and distinct results for each biopsy.

In four major published studies in major journals, PyloriTek has been shown to meet the most widely accepted sensitivity and specificity criteria for diagnosing H. pylori infections. In carefully controlled studies involving over 500 patients, PyloriTek, when compared to at least two reference methods, showed average specificity of over 97% and sensitivity of over 96%. This is not data from a single selected study which shows the best results from one institution, but a summary from all the institutions which have done unbiased studies comparing PyloriTek to other RUT tests and histology methods. Two additional papers are available, including a new pediatric study. Reprints are available from your exclusive PyloriTek distributor or directly from Serim.

But do not just take our word for the superiority of PyloriTek. Ask your exclusive PyloriTek distributor for copies of journal reprints or the names of satisfied users with whom you can speak about the benefits of PyloriTek.