Löwenstein-Jensen media. No longer necessary for mycobacterial isolation.

Isolation of mycobacteria on Löwenstein-Jensen media (LJ) and in the BACTEC MB9000 (MB) system was compared. Of 2,271 specimens, 317 were positive for 331 mycobacteria isolated in 1 or both media. The MB was positive in 238 isolates, and LJ was positive for 239 isolates; 92 isolates were detected by MB only and 93 by LJ only. Of the 331 isolates, 146 were recovered by both media. MB recovered 38 of 38 Mycobacterium tuberculosis complex isolates, while LJ recovered 23. MB recovered 94.1% (96/102) of Mycobacterium avium complex isolates and LJ 69.6% (71/102). The MB recovered 81% (65/80) Mycobacterium fortuitum-chelonae isolates and LJ 68% (54/80). Of the remaining species, MB isolated 39, while LJ isolated 91. Only 1 organism that was isolated on LJ alone was medically significant based on medical record review. The addition of LJ media to the MB9000 system is not warranted, as it causes clinically irrelevant workload, increased expenditures for the laboratory, and could cause the inappropriate treatment of patients.

Effective reporting of susceptibility test results.

An overview of effective reporting of susceptibility test results is presented. Areas included in effective antimicrobial reporting are selective reporting of antimicrobials within drug families and by specific drug-organism combinations, automatic computer-delivered susceptibilities to patient-care areas, "flagged" results that are unusual and/or could seriously effect patient care, and the use of a coherent report format. Also included are areas that may significantly enhance antimicrobial result formats such as the reporting of cost information with susceptibility results, reporting "predictive sensitivities" based on institutional antibiograms, and reporting specific drugs for therapy based on gram's stain, and preliminary and final culture information.

Comparison of blood-culture results after five and seven days of incubation using the BACTEC NR660.

We compared 16,606 blood cultures for microbial growth on days 5, 6, and 7 of incubation using the BACTEC NR660. Only 20 potentially significant organisms (0.8% of positive cultures) were detected after day 5 and only one resulted in a change of patient management. We recommend users of the BACTEC NR660 consider a 5-day protocol for routine blood cultures.

Lactococcus garvieae endocarditis: report of a case and review of the literature.

Bacterial endocarditis due to Lactococcus garvieae is extremely unusual, and may actually be underreported due to its morphologic and biochemical similarities with enterococci. Only three cases have been reported in the medical literature, and all involved prosthetic valves. We report a case of native valve bacterial endocarditis caused by L. garvieae.

Evaluation of the mycobacteria growth indicator tube compared to Septi-Chek AFB for the detection of mycobacteria.

The Mycobacteria Growth Indicator Tube (MGIT) and the AFB Septi-Check (SC) systems were compared for the ability to detect myobacterial isolates, time to detection, and rate of bacterial contamination. Fifty-eight mycobacterial culture positive specimens were studied. MGIT and SC were both positive in 30 of the 58 specimens (52%); SC alone was positive in 22 (38%), and MGIT alone was positive in 6 (10%) of the 58 specimens. Among the 30 isolates identified in both systems, there were 7 Mycobacterium tuberculosis, 14 M. avium, 6 M. fortuitum-chelonae complex, and 3 other mycobacterial species. MGIT detected Mycobacterium tuberculosis faster; SC detected M. avium complex faster and more often; and M. fortuitum-chelonae isolates were detected at the same rate. MGIT showed more contamination (12.6%) than did the SC (7.8%). MGIT is comparable to SC for the detection of MTB, but MAC isolates were detected more often and faster in the SC system.

A comparison of the Bactec 9000MB system and the Septi-Chek AFB system for the detection of mycobacteria.

The Bactec MB9000 (MB) continuous monitoring system was compared to the Septic-Chek AFB (SC) for the detection of Mycobacterium species from all patient sources. A total of 1485 specimens were evaluated. Two hundred forty-eight specimens grew mycobacteria in one or both systems. The isolates recovered were 18 Mycobacterium tuberculosis (MTB), 109 M. avium complex (MAC), 59 M. fortuitum-chelonae complex (MFC), 51 pigmented mycobacteria (PGM), and 11 nonpigmented mycobacteria, not MTB/MAC (NP). Of the 248 positive specimens, 157 were positive in both systems; 73 in the SC only; and 18 in the MB only. The mean times to detection for specimens were 11.5 days for MB versus 16.4 days for SC. The false positivity rate in the MB was 5.8%. Contamination rates for the MB and the SC were 12.7% and 19.8%, respectively. These data suggest that the automated MB system has clear advantages over the manual SC system in terms of earlier time to detection of significant mycobacteria, less technical hands-on time, and a lower contamination rate.

Clinical assessment of anaerobic isolates from blood cultures.

Patients at two tertiary-care medical centers were evaluated to determine the clinical significance of anaerobic isolates from their blood specimens and to identify whether aerobic and/or anaerobic conditions were necessary for the detection of Streptococcus pneumoniae isolates. Significant anaerobes were isolated from only 0.1% and 0.4% of all blood cultures collected. The majority of patients with significant anaerobes had clinical conditions in which anaerobes are known to cause infections. Of the S. pneumoniae organisms, 83% were isolated only from the aerobic bottles of a blood culture set. These data lend support to the recommendations for the selective ordering of anaerobic blood cultures without compromising the isolation of S. pneumoniae.

Immunological aspects associated with suppression of hormone levels in rats infected with plerocercoids of Spirometra mansonoides (Cestoda).

The effect of the plerocercoid larvae of Spirometra mansonoides on hormone levels and the immune system of intact and hypophysectomized (Hx) rats was studied. Intact rats exhibited a decrease in serum growth hormone (GH) and thyroxine (T4) concentrations and a suppression of the humoral immune response 2 wk postinfection. At 4 and 9 wk postinfection, hormone concentrations and the humoral immune response returned to normal levels in the rats. When rats were infected with plerocercoids and then received daily injections for 2 wk of either GH or T4, the immune response returned to normal in the T4-injected, but not the GH-injected animals. Plerocercoid infection had no effect on the humoral immune response of Hx rats. The results of the present study suggest that PGF may act via an endocrine pathway to suppress the host's immune response enabling the parasite's survival in this host.

Job-loss insecurity versus job-feature insecurity among medical technologists.

Using a sample of 292 medical technologists surveyed over a three-year period, this study tested the hypothesis that job-loss insecurity and job-feature insecurity were related but distinguishable constructs. Factor analysis supported this hypothesis. In addition, each construct demonstrated a differential pattern to significant antecedents. Specifically, cross-training desire and organizational downsizing were positively related, while job satisfaction was negatively related, to job-loss insecurity. However, team participation and number of professional organization memberships were negatively related, while routine task was positively related, to job-feature insecurity. Study limitations and future research issues are discussed.

Functional-metabolic imaging of neuroblastoma.

Neuroblastoma is the third most common malignant solid tumor of childhood. It originates from primitive neural crest cells of the sympathetic nervous system. Many imaging procedures help guide therapy and predict outcomes. Anatomic imaging methods, such as CT and MRI, are most useful for evaluation of the primary tumor mass and nearby involved lymph nodes. Functional imaging tracers, such as [123I]MIBG, [18F]FDG, and [99mTc]MDP, are used to assess the extent of disease and to search for distant metastases. [123I]MIBG is the principal functional imaging tracer for the detection and monitoring of neuroblastoma. [18F]FDG PET/CT is an alternative that is valuable in tumors with poor or no MIBG-uptake. [99mTc]MDP bone scans may be useful to assess cortical bone metastases. This article will review the use of [123I]MIBG and other functional imaging agents for the management of patients with neuroblastoma.

Spontaneous closure of atrial septal defects in premature vs. full-term neonates.

Our hypotheses were that the following factors influenced closure of atrial septal defects (ASDs) detected in neonates: estimated gestational age (EGA), the presence of a persistent ductus arteriosus (PDA), severity of pulmonary disease, gender, and the initial size of the ASD. Our population consisted of 82 newborns (38 premature and 44 term) who were found before the age of 1 month to have an ASD. Closure of ASDs was analyzed using both Kaplan-Meier survival analysis and the Cox proportional hazards model, each with the five covariates. The hazard ratio (or ratio of instantaneous closure rates) of term vs preterm infants was 3.60 (95% CI = 1.80-7.20), whereas the hazard ratio for infants with a PDA (compared to infants with no PDA) was 2.41 (95% CI = 1.28-4.54). Multivariate analysis showed that each of these terms (PDA and EGA) were independent predictors of ASD closure. The hazard ratio of ASD closure for each of four levels of pulmonary disease was 0.632 [95% CI = 0.453-0.881]. We conclude that the majority of neonatal ASDs will close, with EGA and PDA acting as important influences on closure.

Evaluation of the Triage Micro Parasite Panel for detection of Giardia lamblia, Entamoeba histolytica/Entamoeba dispar, and Cryptosporidium parvum in patient stool specimens.

A study comparing the Triage Micro Parasite Panel (Biosite Diagnostics, Inc., San Diego, Calif.) to conventional O&P examination (O&P) was performed using patient fecal specimens. Five hundred twenty-three stool samples were compared. Nineteen specimens were found to be positive by Triage, and 29 were found to be positive by O&P. Seven specimens were positive for Giardia lamblia, four were positive for Entamoeba histolytica/E. dispar, and three were positive for Cryptosporidium parvum as determined by both methods. There was one false positive by Triage (C. parvum) and four false negatives by O&P (two G. lamblia, one E. histolytica/E. dispar, and one C. parvum). The Triage test accurately detected all 18 specimens that contained one of the three organisms that it was designed to detect. The Triage test is a rapid, easy-to-use enzyme immunoassay for the detection of G. lamblia, E. histolytica/E. dispar, and C. parvum in fresh or fresh-frozen fecal specimens. These data suggest that the Triage test can be used as a screen for the immediate testing of stool specimens for these three pathogenic parasites. If Triage test results are negative, O&P can be performed if parasitic infections other than G. lamblia, E. histolytica/E. dispar, or C. parvum are suspected.

Native valve endocarditis due to Pseudallescheria boydii in a patient with AIDS: case report and review.

A 53-year-old man with AIDS developed mitral valve endocarditis due to infection with the fungus Pseudallescheria boydii. A limited number of cases of prosthetic valve endocarditis caused by this organism have been described. We report a unique case of pseudallescheria infection of a native valve and describe this disease in a patient with AIDS.