Comparison of automated Difco ESP blood culture system with biphasic BBL Septi-Chek system for detection of bloodstream infections in pediatric patients.

We compared the Difco ESP 384 blood culture system with the pediatric Septi-Chek system for the detection of bloodstream infections in pediatric patients. A total of 10,762 blood culture sets included an ESP aerobic bottle and a Septi-Chek bottle. From these cultures, a total of 278 organisms classified as probable pathogens were isolated, including 237 from ESP bottles and 221 from Septi-Chek bottles. This difference was not statistically significant. More organisms classified as possible contaminants were also isolated from ESP bottles (for ESP, 480 bottles; for Septi-Chek, 418 bottles; P < 0.01). The time to detection was shorter for probable pathogens isolated from ESP bottles (median times for organisms isolated from both systems: ESP, 14.0 h; Septi-Chek, 34.5 h; P < 0.001). The proportions of all probable pathogens detected by 24 and 48 h after inoculation were 78 and 96%, respectively, for ESP compared with 31 and 74%, respectively, for Septi-Chek. The time to final identification was also shorter for organisms grown in ESP bottles (median times for organisms isolated from both systems: ESP, 48.8 h; Septi-Chek, 58.5 h; P < or = 0.001). A subset of 4,442 cultures also included an ESP anaerobic bottle in addition to an ESP aerobic bottle and a Septi-Chek bottle. There were no significant differences in the recovery of probable pathogens by any of the possible two bottle combinations, but five anaerobic pathogens were recovered only in the anaerobic bottle. We conclude that the ESP 384 is an excellent system for culturing pediatric blood samples and that it provides for the very rapid detection of bloodstream pathogens.

Resistance to penicillin and non-beta-lactam antibiotics of Streptococcus pneumoniae at a children's hospital.

During a 12-month period we tested all isolates of Streptococcus pneumoniae recovered from patients at St. Louis Children's Hospital for resistance to penicillin and other antibiotics. Twenty-seven (20%) of 136 had relative penicillin resistance (minimum inhibitory concentration 0.1 to 1.0 microgram/ml) and 8 (6%) were fully resistant (minimum inhibitory concentration > or = 2.0 micrograms/ml). Sixteen percent from blood and cerebrospinal fluid were resistant, compared with 30% from other body sites. The resistant isolates were of diverse serotypes and included 38% intermediate and 6% resistant to cefotaxime, 40% resistant to trimethoprim-sulfamethoxazole and 20% resistant to erythromycin. Patients with resistant isolates were more likely to have taken antibiotics of the aminopenicillin class and to be of the white race. We conclude that penicillin-resistant pneumococci, including some with resistance to third generation cephalosporins and some with multidrug resistance to non-beta-lactam antibiotics, are widespread in the St. Louis area. The presence of these stains requires reconsideration of current approaches to the antibiotic therapy of a variety of infectious diseases in which pneumococci play a prominent role.

Comparison of PCR and pp65 antigenemia assay with quantitative shell vial culture for detection of cytomegalovirus in blood leukocytes from solid-organ transplant recipients.

This study compared PCR and an assay for cytomegalovirus (CMV) pp65 antigenemia (CMV-vue; INCSTAR Corp.) with a quantitative shell vial culture (QSVC) technique for the detection of CMV in serial blood specimens from 46 solid-organ transplant recipients. In a comparison based on 535 specimens tested by PCR and QSVC, CMV was detected by PCR in 41 and by QSVC in 37 of 43 recipients at risk of CMV infection. The mean number of days after transplantation of initial detection of CMV was 29.9 for PCR and 34.0 for QSVC (P = 0.01). The antigenemia assay was performed on 395 specimens, including 304 of those also tested by PCR. In these specimens, CMV was detected by the antigenemia assay, QSVC, and PCR in 30, 32, and 35 (respectively) of 38 patients at risk, with no statistically significant difference in the time to detection. Each of the assays detected CMV in similar proportions of patients with and without clinically significant CMV infection. PCR stayed positive longer after transplantation than the other assays but frequently returned to negative when more than 6 months had elapsed after transplantation. The antigenemia assay and PCR stayed positive longer after institution of antiviral therapy than QSVC. PCR can provide highly sensitive detection of CMV viremia, but a PCR assay for CMV is not yet available in kit form. The pp65 antigenemia assay and shell vial culture are quantifiable and comparable in sensitivity. Either is recommended for rapid detection of CMV in blood specimens from solid-organ transplant recipients.

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 less than 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.

Comparison of the Bactec Peds Plus pediatric blood culture vial with Roche pediatric Septi-Chek for blood cultures from pediatric patients.

Equal volumes of blood from 4,112 blood cultures were inoculated into one Bactec Peds Plus bottle and one Roche Septi-Chek bottle. There were no significant differences in the recoveries of bloodstream pathogens. Initial detection occurred earlier with Bactec Peds Plus, while growth on solid media occurred earlier with Roche Septi-Chek.