Optimal use of Myco/F lytic and standard BACTEC blood culture bottles for detection of yeast and mycobacteria.

CONTEXT

The optimal use of dedicated fungal and mycobacterial blood culture bottles, such as the BACTEC Myco/F Lytic bottle, has not been well defined in clinical practice.

OBJECTIVES

To compare the performance of Myco/F Lytic and standard blood culture in clinical practice in an urban tertiary care hospital setting and to implement a strategy for optimal use of Myco/F Lytic culture.

DATA SOURCES

Retrospective review of laboratory records.

RESULTS

Myco/F Lytic culture did not increase detection of yeasts. Nor did it decrease time to detection except for Candida glabrata, where mean time to positivity dropped from 2.6 +/- 1.1 days in standard to 1.8 +/- 0.8 days in Myco/F Lytic culture. Therefore, an algorithm was developed in which Myco/F Lytic culture was reserved primarily for detection of mycobacteria in patients with severely depressed CD4 counts. Implementation of this algorithm led to a sustained 3-fold reduction in Myco/F Lytic blood culture usage.

CONCLUSIONS

Retrospective analysis suggests substantial clinical equivalence of standard blood and Myco/F Lytic culture for detection of yeast. A multifaceted educational approach based on this data led to a sustained change in physician ordering practices and more cost-effective use of resources.