Comparative evaluation of selective and nonselective media for primary isolation of Helicobacter pylori from gastric biopsies.
BACKGROUND
In this study, we compared and evaluated the efficacy of five culture media for the primary isolation of Helicobacter pylori from gastric biopsies.


METHODS
A total of 1,174 biopsies (antrum and corpus) taken from 587 patients were plated in parallel on two selective media--Skirrow's medium and brain-heart infusion (BHI) agar supplemented with 10% sheep blood, polymyxin B, vancomycin, trimethoprim, and amphotericin B (HPA medium), and on three nonselective media--chocolate agar with Isovitalex, Columbia blood agar, and BHI-10% sheep blood agar.


RESULTS
An isolation rate of 57.9% (680 of 1,174) was obtained with a combination of all media. HPA medium gave the highest isolation rate, 99.4% (676 of 680). Chocolate agar, Columbia blood agar, brain-heart blood agar, and Skirrow's medium showed very poor performance (23.5%, 28.5%, 65.9%, and 71% of all isolates, respectively). The number of cultures in HPA medium discarded due to contamination was only 2 (0.32%). There was no difference in the positive rate of culture in HPA medium between the antrum and the corpus of the stomach.


CONCLUSIONS
The HPA medium is superior to Skirrow's medium and nonselective media in promoting growth of H. pylori and, on the basis of these results, we recommended the use of HPA medium for primary isolation of H. pylori from gastric biopsies.
Fresnadillo Martínez
M J
MJ
Department of Microbiology, Hospital Universitario, Salamanca, Spain.
Rodríguez Rincón
M
M
Blázquez de Castro
A M
AM
García Sánchez
E
E
García Sánchez
J E
JE
Trujillano Martín
I
I
Cordero Sánchez
M
M
Alvarez Alvarez
P
P
Paz Bouza
J
J
García-Rodríguez
J A
JA
D001431:Bacteriological Techniques; D001706:Biopsy; D003470:Culture Media; D016481:Helicobacter Infections / Q000382:microbiology* / Q000473:pathology; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D013270:Stomach / Q000382:microbiology* / Q000473:pathology
D003470:Culture Media