Modified selective medium for isolation of Campylobacter spp. from feces: comparison with Preston medium, a blood-free medium, and a filtration system

Abstract

389-393, 1983) selective medium, consisting of cefoperazone (15 mg/liter), rifampin (10 mg/liter), colistin (10,000 IU/liter), and amphotericin B (2 mg/liter) (medium Ml), for the isolation of Campylobacter jejuni and Campylobacter coli from stool specimens was modified as follows: cefoperazone (30 mg/liter), rifampin (10 mg/liter), and amphotericin B (2 mg/liter) (medium M2). A comparative study of the isolation of Campylobacter spp. from stool specimens was carried out with medium Ml; medium M2; a selective blood-free medium consisting (per liter) of charcoal (4 g), ferrous sulfate (0.25 g), sodium pyruvate (0.25 g), casein hydrolysate (3 g), sodium deoxycholate (1 g), nutrient broth no. 2 (25 g), agar (12 g), and cefoperazone (32 mg) (medium M3); and Preston medium containing (per liter) trimethoprim (10 mg), rifampin (10 mg), polymyxin B (5,000 IU), and cycloheximide (100 mg) (medium M4). We also included a filtration system in which membrane filters were applied directly to the surface of the nonselective blood-free medium distributed in small petri dishes. A total of 5,276 stool specimens were tested: 2,788 stool specimens were tested on Ml and M3 in study 1; 2,488 stool specimens were inoculated on the four selective media in study 2, and the last 986 specimens of the 2,488 were tested in parallel with the filtration system. In study 2, 128 Campylobacter strains were isolated from 126 different patients; 85.0, 88.3, 82.5, and 66.6% of these strains were isolated on Ml, M2, M3, and M4, respectively. No contaminating fecal flora was found on 65.4, 70.7, 62.4, and 40.3% of the Ml, M2, M3, and M4 plates, respectively. Furthermore, C. coli was found to be more susceptible to antibiotics present in the selective media, particularly colistin and polymyxin B, than was C. jejuni. We therefore recommend M2 for the isolation of Campylobacter spp. Finally, the filtration method was found to be easy and cheap; although the sensitivity was low, this method allowed the isolation of new Campylobacter spp. which seem to be associated with diarrhea.

Knowledge gaps in control ofCampylobacterfor prevention of campylobacteriosis

“…Several methods are available to achieve an opti- (Agulla et al, 1987). For example, some strains of C. coli are sensitive to polymyxin B and may therefore be inhibited in Preston enrichment broth or Preston agar (Goossens et al, 1986),…”

Campylobacter, from obscurity to celebrity

“…In 1977, Skirrow [24] confirmed the findings of the Belgian team and described a simpler technique for culturing C. jejuni and C. coli from stool specimens, which allowed widespread isolation of these organisms. The later development of selective media, obviating the need to filter suspensions, brought the isolation of Campylobacter into the realm of routine microbiology [24][25][26][27][28][29][30]. Reports from industrialised countries, including European countries [19][20][21]24,[30][31][32][33], Canada [34] and the USA [35], and from developing countries, including Zaire [23] and Rwanda [36], have shown that Campylobacter enteritis occurs worldwide.…”

“…jejuni and C. coli can be isolated easily from faeces by primary plating on selective media and incubation for 48-72 h at 42°C in a microaerobic atmosphere. A variety of selective media (bloodbased, blood-free charcoal-based) are available [24][25][26][27][28][29][30]. These contain antibiotics that suppress the normal bacterial enteric flora.…”

Evaluation of the effect of temperature and nutrients on the survival ofCampylobacterspp. in water microcosms

“…The persistence of non-jejuni species of thermophilic Campylobacter has received little attention from the scientific community, presumably because of the relatively low isolation rate of these species from surface waters (Bolton et al 1987). However, this may be as a consequence of the application of selective regimes inhibitory towards non-jejuni species (Goossens et al 1986). Under all imposed conditions, the overall decay rates of thermophilic non-jejuni isolates were more negative than those of Camp.…”