The clinical importance of microbiological findings in the diagnosis and management of bloodstream infections.

Bloodstream infections are associated with high morbidity and mortality. Accurate identification of blood isolates to the species level and identification of the source of infection and/or the portal of entry are crucial for optimal management of these infections. These investigations-in addition to clinical findings and laboratory and imaging studies-are central to informing and directing efficient and effective diagnostic examinations and to choosing the optimal antimicrobial regimen. Four case studies that demonstrate the importance of identifying the causative agents and the source of infection are discussed to illustrate the central importance of microbiological findings in the diagnosis of bacteremia and bloodstream infections associated with infections at other sites.