Of a total of 81 patients hospitalized in the infectious diseases department in 1990-2000 with infectious endocarditis caused by Gram-positive pathogen, unusual etiological agents were found in several cases: Streptococcus pyogenes, Streptococcus pneumoniae, Corynebacterium diphtheriae, and Gemella morbillorum. Cardiac defects were present in the latter two patients: bicuspid aortic valve and tetralogy of Fallot.
Two patients were successfully treated with antibiotics only and one patient with antibiotics and surgery. The patient with C. diphtheriae endocarditis died due to progressive sepsis and multiple organ failure.