Gastric cancer is the major cancer in the developing world and one of the top two worldwide. Helicobacter pylori is a bacterium implicated in the etiology of stomach cancer. The incidence of stomach cancer is lower in individuals and populations with high Allium vegetable intakes. Allium vegetables, particularly garlic, have antibiotic activity. Standard antibiotic regimens against H. pylori are frequently ineffective in high-risk populations. As part of our study of the role of Allium vegetable intake on cancer prevention, we wished to investigate its antimicrobial activity against H. pylori. An aqueous extract of garlic cloves was standardized for its thiosulfinate concentration and tested for its antimicrobial activity on H. pylori grown on chocolate agar plates. Minimum inhibitory concentration was 40 micrograms thiosulfinate per milliliter. Staphylococcus aureus tested under the same conditions was not susceptible to garlic extract up to the maximum thiosulfinate concentration tested (160 micrograms/ml). To our knowledge, this is the first report of H. pylori's susceptibility to garlic extract of known thiosulfinate concentration. It is plausible that the sensitivity of H. pylori to garlic extract at such low concentration may be related to the reported lower risk of stomach cancer in those with a high Allium vegetable intake. Furthermore, it may identify a strategy for a low-cost intervention, with few side effects, in populations at high risk for stomach cancer, particularly where antibiotic resistance and the risk of reinfection are high.

.7% of all samples tested, and no significant differences in sensitivity or specificity were noted between HSCT and non-HSCT patients. IAs, while not as sensitive as direct fecal CBA, produce reasonable predictive values, especially when both antigen and toxin are detected. They also offer significant advantages over CBA in terms of turnaround time and ease of use.

Studies have shown that vancomycin broth enrichment is superior to direct plating for the detection of vancomycin-resistant enterococcus (VRE), but vancomycin selective broth is not generally commercially available. We developed an easy-to-prepare VRE selective differential broth and compared it to direct plating on bile esculin azide (BEA) agar for the isolation of VRE from fecal samples. A total of 528 consecutive rectal swabs and stools were inoculated onto BEA agar and into BEA broth with vancomycin at a concentration of 15 g/ml (BEA VAN 15g/ml broth). After 1 to 2 days of incubation, broths were subcultured to BEA VAN 6g/ml agar. Bile esculin-positive colonies from the direct and broth subculture plates were evaluated for the presence of VRE by standard microbiological techniques. Addition of the broth enrichment step led to the detection of significantly more VRE isolates than did direct plating alone (28 versus 18 VRE isolates, respectively). In all, 30 VRE strains were isolated from 29 cultures, all of which were Enterococcus faecium. MICs of vancomycin ranged from 32 g/ml (n ‫؍‬ 2) to > 256 g/ml (n ‫؍‬ 28). Twenty-two VRE isolates were available for further testing: sixteen exhibited a VanA phenotype and six were of the VanB phenotype. van genotypes were in agreement with phenotypes for all VRE isolates except one, which could not be genotyped. The broth method also resulted in significantly fewer bile esculin-positive, non-VRE isolates requiring further workup. We have thus developed an easily prepared vancomycin selective differential broth that is significantly more sensitive and specific in the detection of VRE than is direct fecal plating to BEA agar.

An immunofluorescent-antibody test was developed for rapid detection of Pseudomonas aeruginosa in blood cultures. The test uses a murine monoclonal antibody specific for all strains of P. aeruginosa. In initial tests, bright uniform immunofluorescence signals were seen when each of the 17 international serotypes, as well as 14 additional isolates of P. aeruginosa, were examined. No immunofluorescent staining was observed when 37 other gram-negative and 15 gram-positive species were studied. In a clinical study, the assay was applied to broth smears of 86 gram-negative bacilli isolated from 74 bacteremic patients and 28 additional clinical isolates of Pseudomonas sp. and other oxidase-positive gram-negative bacilli recovered from various other body sites. Smears were made directly from blood cultures which were positive for gram-negative bacilli by Gram staining. Eleven (15%) of 74 patients with gram-negative bacteremia had a positive test for P. aeruginosa. Including the results of these 11 isolates recovered in a prospective study and an additional 10 isolates from a retrospective study, we obtained a sensitivity and specificity of 100% (21 positive specimens and 103 negative specimens, respectively). These preliminary results suggest that this is a useful reagent for rapid presumptive identification of P. aeruginosa in blood cultures. With the immunofluorescent-antibody test, P. aeruginosa could be identified within 1 h of Gram stain evidence of gram-negative bacteremia. Pseudomonas aeruginosa is an important cause of nosocomial bacteremia and pneumonia, especially in immunocompromised patients. In patients receiving organ transplants, this organism was the most common cause of bacteremia among the aerobic gram-negative bacilli and was responsible for 50 (28%) of 180 episodes (4). Case fatality rates ranged from 30 to 50%, despite the use of antibiotics (2, 18; V. T. Andriole, editorial, J. Lab. Clin. Med. 94:196-199), and have consistently remained higher than the mortality associated with bacteremia caused by other gram-negative bacilli (23). Nonetheless, early institution of appropriate antibiotics improves the outcome of P. aeruginosa bacteremia, even in neutropenic patients (3, 23). A review of 410 infections in cancer patients showed that cure rates were reduced from 74 to 46% in patients in whom there was a 1to 2-day delay in the use of appropriate antibiotics (3). Therefore, there is an obvious need for laboratory techniques which permit more rapid identification of P. aeruginosa. The P. aeruginosa immunofluorescent-antibody (IFA) test (Genetic Systems Corp., Seattle, Wash.) was evaluated for use in the clinical laboratory as a rapid presumptive identification method for P. aeruginosa isolated from blood cultures. Production of mouse monoclonal antibodies to porin protein F has been reported by others (9, 17). Previous work has also shown that certain epitopes on this protein may be present on all P. aeruginosa strains but not other gramnegative species. Antibodies to these epitopes are candidates for a...