Prosthetic valve endocarditis caused by Brucella melitensis. A report of four cases successfully treated with tetracycline, streptomycin, and sulfamethoxazole and trimethoprim plus valve replacement.

Optimal treatment of prosthetic valve endocarditis due to Brucella melitensis is unknown. The presence of ring abscess makes extensive surgical débridement and valve replacement essential steps of management. Antimicrobial therapy with tetracycline hydrochloride plus streptomycin sulfate or sulfamethoxazole and trimethoprim can achieve the sterilization of infected cardiac tissue. Late bland periprosthetic leaks occur frequently. Reoperation can be safely performed after a period of antimicrobial therapy. Prolonged treatment with doxycycline hyclate seems advisable.