Streptococcal Endocarditis Initially Seen as Septic Arthritis

Two patients were initially seen with culture-positive streptococcal arthritis as an early manifestation of bacterial endocarditis. The organisms were an alpha-hemolytic, nongroup D streptococcus and a beta-hemolytic, group b streptococcus. One patient had a persistent septic monarthritis; the other had migratory arthritis in which a positive synovial culture was followed by a negative culture from the same joint before antimicrobial treatment was started. This experience suggests that some sterile synovial aspirates encountered in patients with bacterial endocarditis may be explained by delay of arthrocentesis.