Helicobacter pylori: isolation from gastric biopsy specimens.

Forty-two gastric biopsies, in two transport media, were homogenized and cultured on three media under micro-aerophilic conditions. Brain-heart infusion agar with a commercial antibiotic supplement (giving 10 mg vancomycin, 5 mg trimethoprim and 2500 i.u. polymixin per litre) yielded the best results. Ordinary chocolate (heated) human blood agar could be used in laboratories with limited resources. Growth was obtained in 4-6 days at 37 degrees C. All isolates were sensitive to metronidazole. The resistance to nalidixic acid and rapid urease production of Helicobacter pylori could be used to differentiate this species from Campylobacter spp. Indicator medium (brain-heart infusion broth with 7% human blood and 40 mg 2,3,5-triphenyletetrazolium chloride agar/litre) also proved useful in identification.