What is the optimal medium for recovering Brucella spp. from blood and bone marrow specimens?

The optimal medium for recovering Brucella spp. from blood and bone marrow specimens is biphasic Castenada bottles with Brucella broth. This choice is particularly effective because biphasic culture systems provide both solid and liquid phases, which can enhance the recovery of low-virulence organisms like Brucella. The liquid phase allows for better growth conditions and nutrient availability, while the solid phase can facilitate the observation of colonies during culture.

Brucella spp. are known to require specialized culture conditions due to their fastidious nature, meaning they have specific nutritional requirements that must be met for optimal growth. The use of Brucella broth is important since it is tailored to support the growth of these bacteria specifically, providing the necessary environment and nutrients they need to thrive.

Other options do not provide the same advantages. For instance, blood culture bottles with Brucella broth may not combine the benefits of a solid medium that biphasic systems offer. Similarly, utilizing Bordet-Gengou agar plates, which are designed for Bordetella pertussis, would not be appropriate as it does not support Brucella spp. growth efficiently. Finally, blood culture bottles with THIO broth also lack the specific formulation required for optimal recovery of these