Test for Helicobacter pylori in gastric biopsy specimens
using SERIM PyloriTek test kit
PRINCIPLE H. pylori produces the enzyme
urease which is not present in mammalian tissue. The PyloriTek Test Kit
detects urease activity in gastric biopsy specimens according to the
Urea + H2O -----------à
2 NH3 + CO2
The ammonia produced is detected with a pH indicator (bromophenol blue)
which turns from yellow to blue at an elevated pH.
CLINICAL UTILITY The test is used as an aid in the
presumptive identification of H. pylori infection in patients with clinical
signs and symptoms of gastrointestinal disease.
SPECIMEN PyloriTek Reagent strips allow
individual testing of specimens from multiple areas of the stomach.
Recommendations concerning multiple specimen collection vary. However, one
specimen may be from the greater curvature of the pre-pyloric antrum. A
second specimen may be taken from the antral lesser curvature at or near the
incisura. H.pylori infection may be found in a third biopsy from the
greater curvature of the body of the stomach. Avoid areas of erosion or
ulceration. Up to three biopsy specimens from one patient can be tested on
one PyloriTek Reagent Strip.
A recent report has
indicated specimen size is not critical in obtaining satisfactory results.
SPECIMEN HANDLING PRECAUTIONS
The specimen must be transferred directly from the forceps to the Reaction
Pad, as urease activity in infected specimens can be lost during transport
or storage prior to testing.
Contamination of specimens with formalin (from biopsy forceps or other
sources) can inhibit H. pylori urease activity and lead to false
NORMAL RANGE Negative
COMPUTER CODES N/A
QUALITY CONTROL A small red spot located in the upper
left-hand corner of the Reaction Pad contains urease and provides an
internal POSITIVE REACTIVE CONTROL. An intense purple or blue spot will
develop over the POSTIIVE REACTIVE CONTROL within 60 minutes after the test
Failure of the purple or blue
spot to appear indicates that the test has not developed properly. This is an
invalid test. Perhaps the Hydration Reagent was not applied to the
Substrate Pad or the strip was not properly inserted into the reaction device.
Since urease is present only
in the POSITIVE REACTIVE CONTROL and in infected biopsy specimens, the absence
of purple or blue control in any other areas of the REACTION PAD serves as a
Development of purple or blue
color in these other areas indicates that the strip has not reacted properly or
has reacted due to exposure to excess heat, moisture or ammonia sources.
SHOULD THE CONTROLS REACT
INCORRECTLY, THE TEST IS INVALID AND THE RESULTS MAY NOT BE REPORTED.
Repeat testing on another reagent strip. If problem persists, call the
manufacturer (SERIM) at 1-800-542-4670 or email:
firstname.lastname@example.org for advice.
CALIBRATION None required
PROCEDURE 1. Preparation of Test Strip
Remove a test strip from the bottle, lay it down on a
clean, dry surface. Turn the strip over. Make sure the red Positive
Reactive Control Spot is visible in the upper left-hand corner of the Reaction
Write the patient name or Identification number and the time the
test is started on the lines provided on the front of the strip.
Turn the strip over and crease at the perforation.
Add four drops of Hydration Reagent to the Substrate Pad (one
drop in each corner of the absorbent pad at the end of the strip).
Using a clean applicator stick, plastic pick or any other suitable
accessory, push the gastric specimen from the forceps onto the Reaction Pad.
The specimen should be placed at least 6-7mm (1/4 “) from the red
positive control spot which is visible on the Reaction Pad.
Specimens should be placed near the middle of the slightly raised area of
the Reaction Pad which is on the opposite side from the yellow pH membrane.
1, 2 or three specimens from the same patient can be placed on the pad.
Keep the specimens at least 6-7 mm apart to ensure that each reaction can be
Fold and Insert Test Strip into Chamber
When your gastric specimens
are in place, fold the Substrate Pad on top of the Reaction Pad. Immediately
insert the folded strip, with the yellow side out, into the Reaction Chamber.
Make sure the strip is fully inserted and touches the bottom of the reaction
Within 60 minutes, examine the yellow Reaction Pad for the appearance of
intense dark blue or purple color spots. The purple positive control should
appear in the upper right hand corner. The positive control spot usually
appears within 4-10 minutes but may occasionally take longer.
Most positive patient specimens appear in less than 20 minutes. Some
very strong positives may appear in 1-2 minutes.
NOTE: A positive results may
appear ANYTIME up to the full 60 minutes.
c. For a confirmed positive, BOTH specimen and positive control
must show the
strong blue/purple color.
ALWAYS wait the full 60 minutes before reporting a patient’s results as
Kits are stored in the refrigerator at 2-7oC until the bottle of
reagents is opened. Allow all kit components to come to room temperature (15-30oC
or 59-86oF) prior to use. Do not use kit pass the expiration date.
Once opened, store the kit components at room temperature.
PyloriTek Reagent Strips
Reaction Pad: 0.1%
Bromophenol Blue, 0.2% Sulfamic Acid
Store in the refrigerator at
2-7oC until the bottle is opened for use. Warm to room temperature
prior to use. Promptly replace and tighten cap after removing strip from bottle.
DO NOT REMOVE desiccant, which keeps the strips protected from ambient moisture.
Do not remove strip(s) from bottle until ready to use. DO NOT RETURN any unused
strips that have been exposed to ambient conditions to the bottle. Indicate the
date the bottle is opened on the bottle label. DO NOT USE strips more than 3
months after the bottle has been opened, or after the kit expiration
date, whichever occurs first.
Avoid placing strips near
sources of heat, ammonia (ammonia ampules, ammonia-containing cleaning
compounds) or formaldehyde. Extreme heat or chemical fumes may cause a change
in the background color of the strip.
PyloriTek Hydration Reagent
Contains: 1.8% Tris buffer
Store in the refrigerator at 2-7oC
until the bottle of reagent strips is opened. Allow all kit components to come
to room temperature (15-30oC or 59-86oF) prior to use.
PyloriTek Disposable Reaction Pouches
These are disposable plastic
devices that serve as Reaction Chamber, which may be reused after thorough
cleaning. (If reusing the Reaction chamber: wash in warm soapy water using a
mild detergent, rinse with clean water and dry with a fresh paper towel).
Reaction pouches provide solid contact between the gastric biopsy and the
Substrate Pad and insures that the ammonia gas generated is directed through the
membrane to the pH indicator.
ALWAYS use the Disposable
Reaction pouches to hold strips during the reaction time. DO NOT USE tape or a
Do not carry the pouches with
developing tests in the pockets of your clothes during the one hour development
time. Consider the contents to be a potential biohazard. Do not remove
developing strips from the pouch or re-opening the strips. This may affect the
LIMITATIONS OF PyloriTek Reagent Strips detect ammonia
generated by H.pylori urease-
PROCEDURE catalyzed hydrolysis of urea in the Substrate Pad
A. Ammonia can also be produced by tissue autolysis or can be found in blood as
a waste product. However, these non-specific reactions normally occur at a
slower rate than can be detected visually in 60 minutes by the PyloriTek test.
It is possible that abnormal increases in these reactions may produce a pale
blue or faint gray color over the specimen, which is a negative result.
Negative results may occur if an area is sampled which has not been
colonized, particularly if the patient has been on antibiotic and/or bismuth
A positive test does not distinguish between colonization and a symptomatic
The PyloriTek Test Kit is to be used to aid in diagnosis only with those
patients with clinical symptoms of H.pylori infection.
REFERENCES PYLORITEK TEST KIT, package insert, SERIM
Research Corporation, Elkhart, IN, website: serim.com