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L G Reimer

Publications and source records attributed to L G Reimer.

At least 37 records · Page 2Linked to original sources

Recovery of clinically important microorganisms from the BacT/Alert blood culture system does not require testing for seven days.

Recently, we published a comparison of the BacT/Alert blood culture system with the BACTEC 660/730 nonradiometric blood culture system using blood inocula of 5 ml per bottle. By reanalyzing data collected during that study, we found that, for true-positive isolates causing bacteremia or fungemia, 363 (97.6%) of 376 and 341 (97.7%) of 349 isolates were recovered by the end of day 5 of testing, and 364 (97.9%) of 376 and 343 (98.3%) of 349 isolates were recovered by the end of day 6 of testing for aerobic and anaerobic bottles, respectively. Most isolates recovered on days 6 (24 of 27) and 7 (20 of 25) of testing were either contaminants or indeterminate as a cause of sepsis. When used as recommended by the manufacturer, only six (1.3%) of 464 clinically important isolates recovered on test days 6-7 would have gone undetected had testing been limited to 5 days and four (0.9%) of 464 had testing been limited to 6 days. We conclude that BacT/Alert bottles can be tested for as few as 5 days and then discarded with minimal loss of true-positive isolates and maximal reduction of contaminants.

Bacteremia↗

Q fever.

Q fever is an acute febrile illness first described in 1935 and now seen in many parts of the world. Human infection follows exposure to animals, especially domestic livestock. Recent outbreaks in metropolitan areas have implicated cats as the carrier of disease to humans. The etiologic agent, Coxiella burnetti, belongs to the family Rickettsiaceae, although it has distinct genetic characteristics and modes of transmission. Most recent attention has been focused on a number of large outbreaks of Q fever associated with medical research involving pregnant sheep. Although most infections are self-limited, some patients require prolonged treatment. Recent vaccines have had encouraging success in the prevention of disease in individuals at high risk of exposure.

Acute Disease↗

Controlled comparison of the BacT/Alert and BACTEC 660/730 nonradiometric blood culture systems.

In a collaborative study at three university hospitals, the recovery of microorganisms and the speed of detection of microbial growth by the BacT/Alert (Organon Teknika Corporation, Durham, N.C.) and BACTEC 660/730 (Becton-Dickinson Diagnostic Instrument Systems, Sparks, Md.) nonradiometric blood culture systems were compared. A total of 5,918 comparisons were made between BacT/Alert aerobic and BACTEC NR 6A bottles and 5,992 comparisons were made between BacT/Alert anaerobic and BACTEC NR 7A bottles. Each bottle was inoculated with 5 ml of blood. The overall recoveries of microorganisms from the two aerobic bottles were comparable; members of the family Enterobacteriaceae were recovered more often from BacT/Alert aerobic bottles alone (P less than 0.001). The overall recoveries of microorganisms from the anaerobic bottles were not significantly different. Growth of Staphylococcus aureus (P less than 0.001), coagulase-negative staphylococci (P less than 0.01), streptococci (P less than 0.001), Escherichia coli (P less than 0.01), other members of the family Enterobacteriaceae (P less than 0.02), and Pseudomonas aeruginosa (P less than 0.05) was detected earlier in BacT/Alert aerobic bottles. Growth of S. aureus (P less than 0.001), coagulase-negative staphylococci (P less than 0.05), enterococci (P less than 0.01), Streptococcus pneumoniae (P less than 0.02), viridans group streptococci (P less than 0.05), E. coli (P less than 0.001), Klebsiella pneumoniae (P less than 0.01), and other members of the family Enterobacteriaceae (P less than 0.001) was detected earlier in BacT/Alert anaerobic bottles. In a system-versus-system comparison, more gram-positive cocci were recovered from the BACTEC system alone (P < 0.05), and more members or the family Enterobacteriaceae were recovered from the BacT/Alert system alone (P < 0.001). As a system, the BacT/Alert system detected growth of S. aureus (P < 0.001), coagulase-negative staphylococci (P < 0.01), streptococci (P < 0.001), E. coli (P < 0.001), other members of the familyEnterobacteriaceae (P < 0.001), and P. aeruginosa (P < 0.05) earlier than the BACTEC system did. Significantly fewer (40 versus 1,183) false-positive results occurred with the BacT/Alert system. We conclude that the BacT/Alert and BACTEC 660/730 nonradiometric systems are comparable for recovering clinically significant microorganisms form adult patients with bacteremia or fungemia, but that the BacT/Alert system detects microbial growth earlier than the BACTEC system does, with significantly fewer false-positive results.

Adult↗

Eikenella corrodens chorioamnionitis.

Eikenella corrodens was once considered a microorganism of little clinical consequence. But over the past decade, there has been a marked increase in the number of reports of serious infections caused by this organism. We present a case of E corrodens chorioamnionitis in a patient with intact membranes. This is the second known case of its kind to be reported in the medical literature. The true incidence of obstetric and gynecologic infections may be much higher than reported because of the organism's susceptibility to routine antibiotic regimens and the failure of some strains to exhibit characteristic colony morphology on solid agar.

Adult↗

Effect of altered headspace atmosphere on yield and speed of detection of the Oxoid Signal blood culture system versus the BACTEC radiometric system.

The one-bottle Oxoid Signal blood culture system altered to provide a more aerobic bottle headspace was reassessed in a comparative study versus the two-bottle BACTEC radiometric system in 5,426 blood cultures. The BACTEC system detected more microorganisms (P less than 0.02), particularly anaerobes (P less than 0.05) and fungi (P less than 0.05).

Bacteria↗

Controlled comparison of a new Becton Dickinson agar slant blood culture system with Roche Septi-Chek for the detection of bacteremia and fungemia.

Two commercially available agar slide blood culture systems, Septi-Chek (Roche Diagnostics, Div. Hoffmann-La Roche Inc., Nutley, N.J.) and VACUTAINER agar slant (Becton Dickinson [BD] Vacutainer Systems, Rutherford, N.J.), were compared in 5,628 paired blood cultures from adult patients. The systems were inoculated with equal volumes (5 ml) of blood. There was no statistically significant difference between the two systems in the overall recovery of clinically important microorganisms; however, significantly more Escherichia coli (P less than 0.05) organisms were detected in the Septi-Chek system. Concurrently, significantly more contaminants (P less than 0.001) also were present in Septi-Chek bottles. When microorganisms grew in both systems, there was no significant difference in the time to recovery of important organisms, except that anaerobes were detected more quickly in the BD system. This study suggests that the BD VACUTAINER agar slant is an acceptable alternative to the Septi-Chek system for routine blood cultures.

Bacteria↗

Effect of agitation and terminal subcultures on yield and speed of detection of the Oxoid Signal blood culture system versus the BACTEC radiometric system.

In an initial evaluation, we found the Oxoid Signal blood culture system inferior to the BACTEC radiometric system for detection of some microorganisms causing septicemia (M. P. Weinstein, S. Mirrett, and L. B. Reller, J. Clin. Microbiol. 26:962-964, 1988). To determine whether modified processing of the Oxoid Signal blood culture system could improve its yield and speed of detecting positive cultures relative to the BACTEC radiometric system, we agitated all Oxoid bottles during the first 24 to 48 h of incubation and performed aerobic and anaerobic subcultures of all Oxoid bottles negative after 7 days of incubation. These modifications improved the overall performance of the Oxoid system, particularly with regard to the yield of streptococci, members of the family Enterobacteriaceae, and Haemophilus, Neisseria, and Acinetobacter spp. The speed of detecting positive cultures also was improved, especially within the first 24 h of incubation. However, the BACTEC system still detected more positive cultures (P less than 0.005), especially of obligate aerobes such as Pseudomonas aeruginosa (P less than 0.05) and yeasts (P less than 0.005). The BACTEC system also detected positive cultures earlier than the Oxoid system (e.g., at 24 h of incubation, 70.5% of BACTEC positive cultures detected versus 62.1% of Oxoid positive cultures detected). Further modifications of the Oxoid system which might include a revised medium, additional processing modifications, altered headspace atmosphere, or a complementary second broth medium should be considered, since the system is attractive in concept and is easy to use in the clinical laboratory.

Aerobiosis↗

The power of the individual's story.

A full-time chaplain to transplant patients and their families cautions that the natural sympathy inspired by the plight of individual transplant candidates may lead the public to neglect the less dramatic medical needs of the masses of poor and uninsured.

Health Care Rationing↗

Controlled evaluation of trypticase soy broth with and without gelatin and yeast extract in the detection of bacteremia and fungemia.

The addition of gelatin to blood culture media has been suggested to prevent the inhibition of Neisseria meningitidis, Neisseria gonorrhoeae, Gardnerella vaginalis, and Peptostreptococcus anaerobius that is caused by sodium polyanetholsulfonate. To determine the effect of such supplementation on the overall yield of microorganisms, we compared the yield and speed of detection of clinically important microorganisms from 5422 paired 10-ml samples of blood cultured in Trypticase soy broth (TSB) containing 0.03% sodium polyanetholesulfonate (SPS) and TSB/SPS containing 1.2% gelatin and 1.0% yeast extract (mTSB). The atmosphere of incubation (open venting unit) and ratio of blood to broth (1:5) were the same for both samples. Only cultures with adequate blood sample (greater than or equal to 80% of stated volume) were compared statistically. Addition of gelatin and yeast extract resulted in inhibited growth of Enterobacteriaceae (p less than 0.001), Pseudomonas aeruginosa (p less than 0.01), fungi (p less than 0.05), and the overall set of microorganisms encountered (p less than 0.001). It delayed growth of Enterobacteriaceae (p less than 0.001) but reduced the time to recover staphylococci (p less than 0.02). Of 12 isolates of species usually inhibited by SPS, seven grew only with the addition of gelatin and yeast extract, none grew only without supplementation, and five grew in both media. Although gelatin and yeast extract may improve the yield of some specific bacteria, the routine use of these additives cannot be recommended for all blood culture media.

Adult↗

Effect of antimicrobials on blood cultures in endocarditis.

To study the effect of antimicrobials on bacterial growth in blood cultures, we used both simulated blood cultures and cultures obtained from rabbits with experimental endocarditis. Four strains of bacteria were incubated individually with six antimicrobials in nine blood culture media. Positivity rates varied with the ratio of the antimicrobial concentration to the MIC of the organism: 161 of 162 cultures (99%) were positive when the ratio was less than 1/10; 52 of 108 (48%) were positive when the ratio was between 1/10 and one; and none of 54 were positive when the ratio was greater than one. Endocarditis was produced in 28 rabbits with either E. coli, P. aeruginosa, S. aureus, or viridans streptococcus. Following a single dose of an antimicrobial, blood was taken for culture in eight media. Only for viridans streptococcus did recovery rates vary significantly in different media. Recovery rates for this organism in two supplemented peptone broths (78% and 89%) and in hypertonic supplemented peptone (78%) were each higher than in thioglycolate (22%), Columbia (22%), Bactec aerobic and anaerobic (11%), and trypticase soy broths (11%) (p less than 0.05 for each pair). Growth of bacteria in blood cultures containing antimicrobials depended on the ratio of the antimicrobial concentration to the MIC and, for viridans streptococcus, the blood culture medium.

Animals↗

Measurement of serum bactericidal activity and use of vancomycin for treatment of nutritionally variant streptococcal bacteremia.

Nutritionally variant streptococci appear more resistant to antimicrobial treatment that other viridans streptococci. We describe a patient with nutritionally variant streptococcal bacteremia who responded to treatment with vancomycin. Results of serum bactericidal tests did not vary in six different media and correlated minimally with the serum concentration of vancomycin.

Humans↗

Pseudomonas sp. group Ve-2 bacterial peritonitis in a patient on continuous ambulatory peritoneal dialysis.

Pseudomonas sp. group Ve-2 peritonitis occurred in a patient on continuous ambulatory peritoneal dialysis who had recently completed intraperitoneal cephalosporin therapy for culture-negative peritonitis. This is the second reported case of peritonitis in this population of patients due to this unusual organism, which is usually resistant to most cephalosporin antibiotics.

Anti-Glomerular Basement Membrane Disease↗

Controlled evaluation of modified radiometric blood culture medium supplemented with gelatin for detection of bacteremia and fungemia.

Although the addition of 1.2% gelatin to broth blood culture media containing sodium polyanetholesulfonate has been shown to enhance detection of certain bacteria, including Neisseria meningitidis, N. gonorrhoeae, Peptostreptococcus anaerobius, and Gardnerella vaginalis, the effect of such supplementation on the detection of other microorganisms causing bacteremia and fungemia is not known. Therefore, we studied BACTEC 6B medium with and without gelatin in 6,833 paired comparisons to examine the effects of supplementation on both the yield and the speed of detection of sepsis. More aerobic and facultative bacteria grew in the 6B than in the 6B-gelatin medium (P less than 0.001), especially staphylococci (P less than 0.01), Escherichia coli (P less than 0.01), other members of the family Enterobacteriaceae (P less than 0.05), and Acinetobacter spp. (P less than 0.05). When microorganisms grew in both bottles, they did so earlier in 6B than in 6B-gelatin (P less than 0.001). We conclude that the 6B medium in its present formulation is superior to 6B medium supplemented with 1.2% gelatin.

Bacteria↗

Controlled evaluation of the agar-slide and radiometric blood culture systems for the detection of bacteremia and fungemia.

A commercially available agar-slide blood culture bottle (Septi-Chek; Roche Diagnostics, Div. Hoffman-La Roche, Inc., Nutley, N.J.) was compared with the radiometric blood culture system (BACTEC; Johnston Laboratories, Inc., Towson, Md.) in 8,544 paired blood cultures from adult patients. The systems were inoculated with equal volumes (10 ml) of blood. Overall, there was no statistically significant difference between the two systems in the recovery of clinically important microorganisms, but significantly more members of the family Enterobacteriaceae other than Escherichia coli were detected by the agar-slide system (P less than 0.005). The agar-slide system detected more fungi, and the BACTEC detected more anaerobic bacteria; however, small numbers of recovered organisms precluded statistical significance. When microorganisms grew in both systems, their presence was detected one or more days earlier in the BACTEC (P less than 0.001). More contaminants grew in the agar-slide system (P less than 0.001). Both systems performed well, and either system should provide high yield and prompt detection of positive blood cultures in patients with bacteremia and fungemia if used in an optimal way as recommended by the respective manufacturers.

Bacteria↗

Use of a sodium polyanetholesulfonate disk for the identification of Gardnerella vaginalis.

Several methods have been previously suggested for the presumptive identification of Gardnerella vaginalis in clinical laboratories, but none is entirely satisfactory. We previously found that sodium polyanetholesulfonate (SPS) inhibits G. vaginalis in blood culture media. We compared susceptibility to an SPS-containing paper disk with beta-hemolysis on human blood agar, hippurate hydrolysis, and inhibition by alpha-hemolytic streptococci for identification of 62 previously confirmed G. vaginalis strains. All strains were positive by SPS disk and alpha-hemolytic streptococcus inhibition, 78% were positive by beta-hemolysis, and 81% were positive by hippurate hydrolysis. Although positive reactions occurred with SPS disk and alpha-hemolytic streptococcus tests for 5 and 9 of 84 other bacteria tested, respectively, none of these bacteria were positive for both tests. We conclude that a combination of SPS disk susceptibility and alpha-hemolytic streptococcus inhibition provides excellent identification of G. vaginalis when performed by the methods suggested.

Bacteriological Techniques↗

Controlled evaluation of supplemented peptone and Bactec blood culture broths for the detection of bacteremia and fungemia.

Comparison of conventional blood culture media with newer formulations of Bactec media for radiometric detection are lacking. Therefore, we compared the yield and speed of detection of clinically important microorganisms with supplemented peptone broth (SPB) and Bactec aerobic (6B) and anaerobic (7C or 7D) broths in 7,627 blood samples from adult patients. Acridine orange stains from SPB, radiometric readings from Bactec, and routine subcultures from all bottles were done at the same time intervals. Bactec grew more facultative gram-positive bacteria (P less than 0.02), Bacteroides spp. (P less than 0.001), gram-negative anaerobes (P less than 0.001). The two-bottle Bactec system required less time to detect Staphylococcus aureus (P less than 0.001), facultative gram-positive bacteria (P less than 0.001), Escherichia coli (P less than 0.02), facultative gram-negative bacteria (P less than .001), and fungi (P less than 0.001). Overall, Bactec yielded 11% more microorganisms and detected bacteremia sooner in 18% of samples than did SPB. This advantage was not because of radiometric monitoring, since most positive Bactec bottles were detected macroscopically. SPB offered no advantage for any group of microorganisms. We conclude that Bactec 6B and 7C or 7D broths used as a unit are superior to a single bottle of SPB with an equal volume of blood for the detection of bacteremia and fungemia, and that Bactec's superiority is not due to the method of detection.

Bacteria↗