[Endocarditis caused by Staphylococcus lugdunensis. Hospital incidence]

Abstract

Background: Staphylococcus lugdenensis is a coagulase negative staphylococcus (CNS) associated with a wide spectrum of infections among which infectious endocarditis may be found and in which it is an aggressive pathogen.

Methods: Since 1993 a systematic search for S. lugdenensis in all the staphylococci isolated in blood cultures and the possibility of endocarditis en all of these was determined. A review of all the cases of endocarditis in the literature was performed.

Results: Three cases of endocarditis by S. lugdenensis on the native valve were detected from January 1993 to June 1997. None of the patients presented previous heart disease or risk factors. In all the cases, at least three blood cultures were positive for S. lugdenensis and vegetations were observed by echocardiogram. Despite correct antibiotic treatment, disappearance of fever, negativization of control blood cultures and in the third case, valve replacement, two patients presented heart failure and all died. On review of the literature 31 cases of endocarditis were found with valve replacement and mortality being 55%. It should be indicated that 85% of the patients who survived required surgery.

Conclusions: Endocarditis by S. lugdenensis is a severe infection frequently requiring valve replacement and is associated with a high mortality. Therefore, adequate early identification of the microorganism is necessary distinguishing it from the remaining CNS.