Multicenter Comparison of ESP Culture System II with BACTEC 460TB and with Lowenstein-Jensen Medium for Recovery of Mycobacteria from Different Clinical Specimens, Including Blood

Abstract

The recently developed ESP Culture System II (AccuMed, Chicago, Ill.) was compared with radiometric BACTEC 460TB (Becton Dickinson, Towson, Md.) and with Lowenstein-Jensen medium for recovery of mycobacteria from over 2,500 clinical specimens both of respiratory and nonrespiratory origin, including blood. The majority of the 219 mycobacterial isolates (129) belonged to the Mycobacterium tuberculosis complex, followed by 37 isolates of theMycobacterium avium complex (MAC) and 53 isolates of eight other mycobacterial species. Rates of recovery obtained with BACTEC, ESP, and Lowenstein-Jensen medium were 89, 79, and 64%, respectively, with such differences being statistically significant. Different media and systems appeared to behave differently when the more frequently detected organisms were considered: M. tuberculosis complex isolates grew better with BACTEC, and MAC isolates grew better with ESP. An analysis of the combinations of Lowenstein-Jensen medium with BACTEC and with ESP did not reveal significant differences in recovery rates. With regard to the times needed for the detection of positive cultures, they were significantly longer on Lowenstein-Jensen medium (average, 28 days) than with the remaining two systems, between which there was no difference (average, 18 days). We conclude, therefore, that the ESP system, when used in combination with a solid medium, performs as well as the thoroughly validated radiometric BACTEC system and offers the advantages of full automation and absence of radioisotopes.

Comparison of Recoveries of Mycobacterium tuberculosis Using the Automated BACTEC MGIT 960 System, the BACTEC 460 TB System, and Löwenstein-Jensen Medium

“…We found that the rate of contamination with the 7-ml Bactec MGIT 960 was lower than the values reported previously for other walk-away broth-based systems (1,2,9,10,11) but was in line with the rates of contamination observed with the 4-ml MGIT (4,5,8). However, the concentration of NaOH used in the other walk-away system studies was lower (2%) than that used both in the present study (4%) and in the 4-ml MGIT studies (3%) (1,2,4,5,8,9,10,11). Moreover, the delay between specimen collection and processing due to longer specimen shipment times at some sites (i.e., 2 to 5 days at one of the test sites in the study by Hanna et al) and the different patient population may also explain these discrepancies (2,4).…”

“…In the present study, the automated 7-ml BACTEC MGIT 960 system displayed a rate of recovery (96.4%) of M. tuberculosis higher than those previously reported for the manual 4-ml MGIT, i.e., 89.4% by Pfyffer et al (4), 81.3% by Somoskövi and Magyar (8), and 85% by Piersimoni et al (5), and also higher than those previously reported for the same walk-away system, i.e., 77% by Hanna et al (2) and 88% by Tortoli et al (10). The 7-ml BACTEC MGIT 960 was also more efficient than the similarly fully automated ESP II system (sensitivity, 85.3 and 89%) (9,11) and showed a sensitivity comparable to that of the MB/BacT system (96%) (1).…”

“…Automation of the cultivation process is high on the list of priorities for laboratories dealing with large specimen loads. Although the recently developed MB/BacT (Organon Teknika, Turnhout, Belgium) and ESP II (Difco Laboratories, Detroit, Mich.) culture systems provide a fully automated, walk-away cultivation process, the capacity of these instruments is rather low (MB/BacT, 240 vials per instrument; ESP II, 384 vials per instrument) (1,6,9,11). Therefore, several units are required, which might be expensive even for laboratories in high-income countries.…”

Evaluation of the BacT/ALERT 3D system for recovery and drug susceptibility testing of Mycobacterium tuberculosis

“…However, this system has limitations, such as the necessity of daily manual loading, the possibility of cross‐contamination due to the invasive reading, manual data management, and the creation of radioactive waste. Novel non‐radiometric systems based on liquid culture have been developed with the aim of avoiding these drawbacks [3–5]. One of them is the BacT/ALERT 3D system [6] (bioMérieux, Durham, NC, USA), which is based on the detection of CO 2 released by actively proliferating mycobacteria into the liquid media.…”

Enhanced Diagnostic Yield of Auramine-O Staining and Mycobacteria Growth Indicator Tube Over Ziehl-Neelsen Staining and Lowenstein Jensen Media in Extra-Pulmonary Tuberculosis

“…Many other studies have demonstrated a higher isolation rate of MGIT as compared to L-J media. [8,9,10] Studies have found out a much lower incidence of non-tuberculous mycobacteria (NTM) in India. A study from CMC Vellore found out M. tuberculosis to be the predominant isolate (96.1%) as compared to only 3.9% NTM.…”