A method for the
in vivo detection of
urease-producing
helicobacter in the upper
stomach is disclosed. The dense carrier is divided into two separate groups which are combined with separate
reagent indicators, one of which also contains
urea. The carriers are food soluble products, preferably
sugar beads having a
diameter of approximately 0.2 to 3.0 mm. The treated carriers and
urea are encapsulated in a soluble
capsule which is administered to a patient. The density of the carriers cause the
capsule to migrate to the
gastric mucosa, where the
capsule, but not the reagents, is dissolved, placing the reagents and
urea in direct contact with the
gastric mucosa. The urea reacts with any
urease present in the
stomach by creating
ammonia, which increases the pH in the immediate vicinity of the urea containing carrier and indicator beads. The two reagents react differently, through color change, to the increase in pH, which is viewed through use of an
endoscope. A preferred first
reagent is
bromothymol blue (dibromothymolsulfonphthalein), which changes yellow in the presence of
urease, and a preferred second
reagent is
phenol red (phenolsulfonphthalein), which turns red in the presence of urease.