Comparison of resin-containing BACTECTM Plus Aerobic/F* medium with conventional methods for culture of normally sterile body fluids

Abstract

The sensitivity of culture in Bactec TM Plus Aerobic=F Ã culture vials of body¯uids from adult patients at a university hospital was compared with that of conventional culture methods, including enrichment in Schaedler broth. Previous antibiotic therapy was recorded at the time of sampling. Analysis of culture results took account of the clinical signi®cance of isolates and impact on therapy. Of 336 specimens evaluated, 81 (24%) yielded positive cultures, of which 50 cultures (15%) were considered to be clinically signi®cant (yielding 71 isolates) and 31 (9%) were considered contaminated. Of the 71 pathogens, 16 (23%) were isolated in the Bactec system only, whereas 13 (18%) grew in conventional media only; 12 of the latter were strict anaerobes. Among clinically signi®cant positive specimens, 19 (38%) were from patients receiving antibiotic therapy. In 27 cases (8% of all specimens and 54% of signi®cantly positive cultures), the isolation of a pathogen led to modi®cation of therapy. Overall, culture in the Bactec system showed higher sensitivity for the isolation of aerobic micro-organisms than Schaedler broth. Most of the difference was due to a better recovery of Streptococcaceae. Additional pathogens found only in resin-containing Bactec media led to 30% of all culture-in¯uenced modi®cations of empirical therapy. These data con®rm that culture of normally sterile body¯uids frequently yields results that are useful for guiding therapy. Although more costly than standard enrichment broth, the resin-containing Bactec Plus Aerobic=F Ã vial can be advantageous for culture of aerobic pathogens from these specimens, particularly in patients receiving antibiotic therapy.

Bacteriological Profile and Antimicrobial Sensitivity Pattern in Sterile Body Fluids from a Tertiary Care Hospital

“…can be infected by various pathogens. In this study 30% samples give culture positive result, which is in comparison to other studies conducted on similar lines, were 31% and 24% positive results [5,6]. A total of 405 samples were studied out of which, 156 were peritoneal fluids, 140 were pleural fluids, 93 were synovial fluids and 16 were pericardial fluid samples.…”

Superior detection of pathogens in synovial fluid by the Bactec 9240 Peds Plus/F system compared to the conventional agar-based culture method

“…The increased yield of pathogens detected by the Bactec systems can primarily be ascribed to the increased volume of sample that can be inoculated into the vials. 8 Alternative methods such as sample concentration (by centrifugation before inoculation of solid agar media) may also result in an increased yield when the conventional method is used. 8 Significantly more contaminants were isolated from the Bactec methods within the first three days of incubation (p=0.027).…”

“…However, culture of synovial fluid in patients with suspected septic arthritis is frequently disappointing and a causative organism is only recovered in one-to two-thirds of cases. [3][4][5][6][7][8][9][10] Factors contributing to this problem include prior administration of antibiotics, inappropriate specimen collection procedures, delayed transport to the laboratory and suboptimal isolation techniques. [3][4][5][6][7][8][9][10] The yield of conventional agar-based culture methods is limited due to the low volume of fluid cultured, which necessitates concentration of the fluid prior to inoculation of media.…”

“…[3][4][5][6][7][8][9][10] Factors contributing to this problem include prior administration of antibiotics, inappropriate specimen collection procedures, delayed transport to the laboratory and suboptimal isolation techniques. [3][4][5][6][7][8][9][10] The yield of conventional agar-based culture methods is limited due to the low volume of fluid cultured, which necessitates concentration of the fluid prior to inoculation of media. 4,5,7 Furthermore, overgrowth by contaminating microflora, the bacteriostatic effect of purulent exudates on bacterial growth, phagocytosis of microorganisms by pus cells in the fluid and the inherent fastidious nature of some pathogens may be responsible for false negative cultures.…”

The value of synovial fluid assays in the diagnosis of joint disease: a literature survey

“…21 There are also recent reports that commercial blood culture systems (for example, "BACTEC plus Aerobic/F" medium) increase the chances of culturing aerobic pathogens from joint fluids, particularly in patients receiving antibiotic treatment. 22 Freemont and others have emphasised the value of other SF tests, 17 23 such as the proportion of polymorphonuclear (PMN) cells, as important adjuncts to the diagnosis of septic arthritis.…”