Unsuccessful treatment of staphylococcal endocarditis with cefazolin.

Two patients with staphylococcal endocarditis were treated unsuccessfully with cefazolin sodium. One patient relapsed after 52 days of therapy. The second patient had concomitant central nervous system infection and failed to respond to cefazolin therapy. Both patients recovered with methicillin sodium or nafcillin sodium therapy. Other studies report unsuccessful therapy of staphylococcal endocarditis with cefazolin.