Supplemented Peptone Broth Research Articles

A blood micro-culture system for the diagnosis of bacteremia in pediatric patients.

The aim of this study was to evaluate the utility of a volume-modified blood culture system to diagnose bacteremia in newborns and infants. A total of 793 paired blood cultures, obtained from 464 patients (173 newborns and 291 infants), were analyzed. Vacutainer tubes containing 18 ml supplemented peptone broth sodium-polyanethol-sulfonate were used as the gold standard, in comparison with a blood micro-culture system containing 1.8 ml of the broth. Prior to antibiotic treatment, 2.2 ml of blood was obtained from each patient; 0.2 ml was inoculated in a blood micro-culture tube and 2 ml in a routine tube. Sensitivity, specificity and predictive values were calculated. Microorganisms were isolated in 153 standard blood culture tubes and 151 blood micro-culture tubes. The sensitivity of the blood micro-culture system was 95%, specificity 99% and positive and negative predictive values 96% and 99% respectively. The sensitivity and specificity of blood micro-culture in neonates and infants is high. We recommend that this system be used for the diagnosis of bacteremia in newborns and infants in laboratories where manual systems are still in use.

Evaluation of three commercially available blood culture systems for cultivation of Helicobacter pylori

Helicobacter pylori is unable to grow in regular blood culture systems, including the BACTEC (Johnston Laboratories), Septi-Chek (Hoffman-La Roche), and Bacto (Difco) systems. We tested three blood culture systems used for fastidious organisms: brucella broth with SPS and CO2 (Becton Dickinson), biphasic brain heart infusion agar or broth (Becton Dickinson), and supplemented peptone broth (Vacutainer). Blood culture bottles were inoculated with H. pylori and human blood and were then incubated by routine diagnostic laboratory procedures. All three blood culture systems were able to sustain the growth of H. pylori, but brucella broth had the highest CFU per milliliter after 72 h. We conclude that a diagnostic laboratory should be able to detect H. pylori bacteremia in a majority of cases by using brucella blood culture bottles.

Evaluation of the pediatric Septi-Chek blood culture system

The pediatric Septi-Chek blood culture system is a biphasic system that uses a 20-ml bottle of brain-heart infusion broth. We compared this system with a supplemented peptone broth tube (Vacutainer) for the recovery of aerobic organisms from blood cultures obtained from patients in a pediatric hospital. Blood specimens for culture were drawn into transport tubes containing sodium polyanetholsulfonate (SPS), and equal volumes were allocated into a Septi-Chek bottle and a Vacutainer tube which was vented for the first day of incubation. A total of 4828 blood culture sets was included, from which 243 probable pathogens were recovered, including 211 in the Septi-Chek system and 204 from the Vacutainer tube. There were no significant differences in the recovery of individual pathogens. The mean time to initial detection of pathogens was comparable in the two systems, but the mean time to growth on solid media for pathogens recovered in both systems was shorter with Septi-Chek (37.2 hr compared with 45.5 hr, p < 0.001). The pediatric Septi-Chek system is comparable with a vented Vacutainer tube for the recovery of aerobic pathogens, and its use facilitates the early identification and susceptibility testing of bloodstream pathogens.

Evaluation of broth media for routine culture of cerebrospinal and joint fluid specimens.

Broth cultures of cerebrospinal and joint fluids are important components in the culture detection of meningitis and septic arthritis. The authors examined 121 strains of bacteria isolated from clinical specimens representing 13 species or groups that cause meningitis and arthritis for growth in supplemented Thioglycolate broth (THIO), Supplemented Peptone Broth (SPB), and minced beef heart (MBH) media each alone or with added IsoVitaleX. Both SPB and MBH with IsoVitaleX performed better as broth culture media than the media without IsoVitaleX or THIO with or without IsoVitaleX.

Biosynthesis of androgen from cortisol by a species of Clostridium recovered from human fecal flora.

A hitherto unknown species of Clostridium, provisionally designated strain 19, was isolated from the fecal flora of a healthy human adult. This strain synthesizes a constitutive desmolase that cleaves the side chain of cortisol to form 11 beta-hydroxy-4-androstene-3,17-dione. The enzymatic conversion is best demonstrated in supplemented peptone broth and in prereduced brain-heart infusion broth. The fecal concentration of strain 19 is 10(7)-10(8) cells/g. The strain adapts with difficulty to growth on Mueller-Hinton agar and Columbia agar base; colony formation is enhanced by the addition of 5% sheep blood. The organism is sensitive to penicillin G and resistant to tetracycline, chloramphenicol, clindamycin, and erythromycin.

Controlled evaluation of hypertonic sucrose medium at a 1:5 ratio of blood to broth for detection of bacteremia and fungemia in supplemented peptone broth.

The value of hypertonic media in the detection of bacteremia and fungemia is controversial, since prior clinical trials have yielded conflicting results with different media. Earlier, we showed that the addition of 10% sucrose to supplemented peptone broth at a 1:10 ratio of blood to broth yielded better recovery of Staphylococcus epidermidis, the Enterobacteriaceae, Pseudomonas aeruginosa, and yeasts. To evaluate the effect of 10% sucrose on blood cultured at a 1:5 ratio, we compared the yield and speed of detection of clinically important microorganisms from adult patients in 5,839 blood samples cultured in supplemented peptone broth with 0.03% sodium polyanetholesulfonate with and without 10% sucrose. The atmosphere of incubation (open venting units), 1:5 ratio of blood to broth, and methods of processing were the same for both bottles. Recovery of facultative gram-positive (P less than 0.02) and gram-negative (P less than 0.02) bacteria was improved, but the recovery of anaerobic gram-negative bacteria was both reduced (P less than 0.01) and delayed (P less than 0.02) by sucrose. The total yield of microorganisms including fungi, however, was increased with sucrose. The effect of sucrose on blood cultures appears to depend on the ratio of blood to broth as well as on the medium used and strains of microorganisms encountered.

Controlled evaluation of hypertonic sucrose medium for detection of bacteremia and fungemia in supplemented peptone broth

Because the value of hypertonic media in detection of bacteremia and fungemia is controversial, we evaluated supplemented peptone broth (SPB) with 0.03% sodium polyanetholsulfonate with and without 10% sucrose in 5,439 paired blood cultures from adult patients. The aerobic atmosphere, 1:10 ratio of blood to broth, and methods for processing blood cultures were identical. Only cultures with adequate blood samples (greater than or equal to 4 ml) were compared statistically. More clinically important bacteria were recovered from SPB with sucrose (P less than or equal to 0.001), including Staphylococcus epidermidis, Enterobacteriaceae, and Bacteroidaceae. However, only one of nine isolates of Neisseria gonorrhoeae grew in SPB with sucrose. Staphylococci (P less than 0.001), Enterobacteriaceae (P less than 0.01), Pseudomonas aeruginosa (P less than 0.01), and yeasts (P less than 0.05) were detected 1 or more days earlier in SPB with sucrose. The effect of sucrose on blood cultures appears to be medium dependent, based on comparisons of our results with those of published reports.

Controlled evaluation of the effect of atmosphere of incubation on detection of bacteremia and fungemia in supplemented peptone broth.

To evaluate the role of atmosphere of incubation in the detection of clinically important bacteremia and fungemia in adults, we compared the yield of microorganisms from 10,541 paired 5-ml samples of blood incubated aerobically and anaerobically. The medium, supplemented peptone broth (SPB) with 0.03% sodium polyanetholesulfonate, and the ratio of blood to broth (1:10) were the same for all cultures. Only cultures with adequate blood samples (greater than or equal to 80% of stated volume) were compared statistically. More fungi (P less than 10(-7) ) grew in continuously vented bottles of SPB. Aerobic incubation also favored (P less than 0.01) isolation of Neisseria gonorrhoeae and Eubacterium; more than 80% of these bacterial organisms were detected only in vented bottles. Anaerobic incubation (plugged venting units) did not significantly favor the isolation of any genus of microorganisms, although an estimated 11% more Bacteroidaceae grew in the unvented bottle of SPB. By comparison of our data with published results for other media, we conclude that the need for both aerobic and anaerobic incubation of blood cultures is dependent upon the medium used and the microorganisms likely to be encountered. Vented incubation of blood cultured in SPB is crucial for detection of fungi and some bacteria. Routine use of an unvented bottle of SPB may not be worthwhile for patients in whom Bacteroidaceae cause bacteremia infrequently. However, when Bacteroidaceae are suspected as the cause of sepsis, use of an unvented bottle of SPB is prudent.

Controlled evaluation of the volume of blood cultured in detection of bacteremia and fungemia.

To evaluate the role of the volume of blood cultured in the detection of clinically important bacteremia and fungemia in adults, we evaluated the yield and speed of detection of microorganisms from 5,317 paired 2- and 5-ml samples of blood. The same kind of medium (supplemented peptone broth with 0.03% sodium polyanetholsulfonate) and atmosphere of incubation (open venting units) were used for all blood cultures. Only adequately filled (less than or equal to 80% of stated volume) sets (20-ml tube and 50-ml bottle) were compared statistically. Significantly more bacteria (p less than 0.01), Pseudomonas spp. In particular (P less than 0.05), were isolated from the 5-ml samples of blood. We conclude that the volume of blood cultured is a critical factor in the detection of septicemia. Consequently, valid evaluation of other factors influencing the detection of septicemia must be based on comparisons in which equal volumes of blood are cultured.

The importance of blood volume cultured on detection of bacteraemia.

The effect of culturing 2 and 5 ml of blood in 18 ml of supplemented peptone broth I (SPB I) and 45 ml of supplemented broth II (SPB II) respectively, was compared. A total of 204 isolates were recovered from 78 patients. There were 136 isolates recovered from both the 45 and the 18 ml tubes. 20 isolates from the 18 ml tube only and 48 isolates from the 45 ml tube only. Both Gram-negative bacilli and Gram-positive cocci were recovered more frequently from the 45 ml tube than from the 18 ml tube (p less than 0.05). From patients with two or more positive blood cultures the diagnosis of bacteraemia would not have been made in 5 out of 53 patients (9.4%) if only the small culture tube had been used.

A new anaerobic blood culture medium: Laboratory evaluation

A new medium, Diagnostic Anaerobic Growth Medium (DAG) was evolved for the culture of anaerobic bacteria from blood. Redox potential measurements of DAG, in comparison with four other commonly used media (supplemented peptone broth; thioglycollate broth; chopped meat glucose broth; tryptone soya broth) showed that Ecal of DAG medium to be lower than that of the other media tested. The new medium recovered more quickly after addition of blood, to reach "blank" values within 4 h. Growth curves of 21 anaerobic bacteria in DAG medium showed that they all multiplied satisfactorily.

Improved blood culture technique based on centrifugation: clinical evaluation

A total of 3,335 blood samples from 1,180 patients suspected of having bacteremia were analyzed concurrently by two methods: (i) supplemented peptone broth with sodium polyanethanol sulfonate and a CO2 atmosphere; and (ii) lysis centrifugation at 3,000 X g for 30 min onto a high-density, hydrophobic cushion. The centrifugation technique recovered 80% of the positive cultures as compared with 67% for the broth method. The centrifugation technique showed an apparent increase in the isolation of staphylococcus aureus, Pseudomonas, and yeasts. In almost every instance, the time required for detection of a positive culture was shortest for the centrifugation method. Contamination rates for both systems were comparable (1.4%). Quantitation, offered only by the centrifugation method, proved useful on several occasions in discriminating between an opportunistic infection versus a skin contaminant and in judging efficacy of antimicrobial therapy.

Comparative evaluation of different types of blood culture media for isolation of aerobes

The possible advantage of hypertonic sucrose medium over isotonic medium for isolating aerobic organisms from blood was studied. Approximately 50 ml of medium and 5 ml of blood inoculum were present in each culture bottle. In the first phase of the study, supplemented peptone broth (SPB) was compared with brucella broth containing 10% sucrose (BB-10S). There were 194 significant clinical isolates in at least one of the two bottles in each set during a 7-month period; 160 (82%) of the isolates grew in SPB, whereas 191 (98%) grew in BB-10S (P less than 0.01). Of the 158 isolates that grew in both media, 13 (8%) appeared earlier in BB-10S, whereas none did so in SPB. In the second phase of the study, SPB with 10% sucrose (SPB-10S) was compared with BB-10S. There were 187 isolates during a 9-month period; 173 (93%) grew in SPB-10S compared with 179 (96%) for BB-10S. In this comparison there was no apparent difference in the time interval required for recovery of organisms. The two hypertonic sucrose media (SPB-10S and BB-10S) were comparable for isolating organisms under aerobic conditions and superior to the nonhypertonic medium (SPB).

Septic and Crystalline Joint Disease

Bacteria and crystals were simultaneously recovered from the synovial fluid of two patients with acutely inflamed joints. The bacteria were initially identified on Gram stain and subsequently grown on supplemented peptone broth, and the crystals were readily identified by polarizing microscopy. Although cause-and-effect relationship between these two types of arthritis cannot be established, the need for thorough examination of synovial fluid is evident.

Detection of Bacteremia with Liquid Media Containing Sodium Polyanetholsulfonate

Two liquid blood culture media, Tryptic soy broth (TSB) and Thiol broth, containing sodium polyanetholsulfonate were compared in 8,654 cultures. Pseudomonas and Corynebacterium (including Propionibacterium) were isolated significantly more frequently (P < 0.001) from TSB than from Thiol. Escherichia coli, Haemophilus, and Bacteroidaceae were isolated more frequently in TSB; however, the differences were not statistically significant. In no instance was Thiol superior to TSB in detecting bacteremia. In an additional 2,977 cultures, aerobic and anaerobic Vacutainer culture tubes with supplemented peptone broth were inoculated in parallel with TSB and Thiol. Significantly greater rates of detection (P < 0.01) in TSB or Thiol were noted with Pseudomonas, E. coli, Enterobacter, viridans, and group A streptococci, Bacteroidaceae, and staphylococci.

Evaluation of B-D Culture Tubes In Parallel with a Conventional Blood Culture System

Our Microbiology Laboratory uses Hyland Bi-Med Triangle Chambers which are flat-sided and contain a stable Eugon broth with a chocolate slant in the aerobic bottle and thiogylcollate broth in the anaerobic bottle. Both chambers contain Polyanethol sodium sulfonate. We compared our method with the new B-D vacutainer culture tube system which is a sterile closed system containing supplemented peptone broth and a yeast extract supplemented with other ingredients. Also added is penicillinase and polyanethol sodium sulfanate.