Rhodococcus equi infection in immunocompromised patients: diagnostic challenges and management insights from two cases.

Rhodococcus equi is an uncommon opportunistic pathogen increasingly recognized in immunocompromised hosts. It typically presents as cavitary pneumonia with bacteremia, particularly among individuals with advanced HIV infection, but may disseminate to virtually any organ. Because of its diphtheroid morphology, it is frequently dismissed as a contaminant, leading to diagnostic delay. Early recognition, accurate identification using advanced microbiologic tools, and initiation of appropriate combination therapy are essential for optimal outcomes. We describe two cases of R. equi pneumonia with bacteremia in immunocompromised patients, requiring prolonged combination antimicrobial therapy. These cases illustrate the diagnostic and therapeutic challenges and emphasize the need for standardized treatment guidelines.