Medium supplementation for growth of Campylobacter pyloridis

Abstract

Experiments were conducted to define the growth requirements of Campylobacter pyloridis, a newly discovered organism associated with gastritis and peptic ulcers. Two clinical isolates were streaked onto various media, and growth was assessed semiquantitatively according to relative colony size and extent of growth through the streak. The growth obtained on fresh chocolate agar, composed of GC agar base (Difco Laboratories, Detroit, Mich.) plus 1% hemin, was used as a reference. The organism grew on both GC agar base and Mueller-Hinton agar without supplementation, but less well than on chocolate agar. No growth occurred on tryptic soy or brucella agar. Supplementation of brucella agar with 1 or 5% horse serum or 0.1 or 1.0% cornstarch supported growth to about the same level as GC agar base alone. Supplementation with hog gastric mucin or methyl cellulose supported weak growth. GC agar base with 1% starch or 0.2% charcoal supported growth as well as chocolate agar. Experiments with brucella broth provided similar results. Cornstarch and methyl cellulose partially replaced the requirement for serum, but methyl cellulose and hog gastric mucin did not. These results show that some form of supplementation is necessary for growth of C. pyloridis. This can be starch, serum, charcoal, or hemin, but hemin is not an absolute requirement for growth.