Blanquita B. de Guzman, Liza P. Faustino, Ma. Corazon 8. Paredes and Filipinas F. Natividad
Research and Biotechnology Division, St. Luke’s Medical Center
doi.org/10.57043/transnastphl.1999.5744
Abstract
In the Philippines, resistance to metronidazole has become a problem in the eradication of Helicobacter pylori, a bacterium known to be the cause for chronic gastritis and peptic ulcer disease. In this study, a new medium was designed to ensure optimum growth of the bacteria for antimicrobial susceptibility testing. This complex basal medium used Columbia Blood agar base, urea agar base plus supplements such as horse serum, polyvitex, and peptone. For culture, antibiotics such as vancomycin, polymixin B, and trimethoprim lactate were added.
Since the medium does not contain whole blood but has urea agar base in its composition, it is suitable for isolating H. pylori as well as direct testing of urease activity. This medium was tested using the six local isolates of H. pylori (as previously reported by the RBD Microbiology Laboratory) plus H. pylori ATCC 49503 strain as reference and other gram-negative bacteria such as Proteus vulgaris ATCC 13315 and Klebsiella pneumoniae. Agar plates which contained this medium were inoculated with the different isolates and bacterial strains then incubated at 37°C in a microaerophilic environment (5% O2, 10% CO2, and 85% N2) for 7 days. Confirmation of H. pylori was done by Gram staining and biochemical tests for catalase, oxidase, and urease.