Five months prior to admission to our hospital, a 71‐year‐old man with end‐stage renal disease who undergoes hemodialysis 3 times per week via an upper‐extremity AV fistula, was diagnosed at his outpatient dialysis center with a bloodstream infection; it was treated for a total of 2 weeks with 6 doses of vancomycin given after dialysis. He was admitted to our hospital with subjective complaints of generalized weakness, fever, neck pain, and an unexplained 9‐kg weight loss. Review of the patient's outpatient dialysis records indicated the bloodstream infection had been identified as coagulas‐negative Staphylococci (CoNS) but had not been speciated. Vital signs were normal. Physical examination revealed bilateral crackles halfway up the lung fields and a grade III/VI holosystolic murmur at the apex consistent with mitral regurgitation. Transesophageal echocardiography revealed a mobile vegetation on the posterior leaflet of the mitral valve with an associated perforation. Blood cultures obtained at admission again grew CoNS, which was speciated as Staphylococcus lugdunensis sensitive to beta‐lactamase antibiotics. A PET‐CT was performed and revealed avid uptake in his C3 vertebral body; a cervical spine MRI confirmed a diskitis/osteomyelitis at the C3/C4 level. The patient was treated with 6 weeks of cefazolin and referred for a mitral valve replacement.
This case presents 1 potential pitfall when final species identification of CoNS is not obtained. A 2011 review of 70 cases of S. lugdunensis infection at a large teaching hospital over the span of 42 months revealed 5 of 21 bacteremias associated with endocarditis (24%), and 2 of 5 patients died before surgery could be performed. Our patient's previous course of vancomycin likely imparted partial treatment where more definitive eradication was necessary to prevent serious infectious complications. This case also illustrates the risk of metastatic Staphylococcal infections in cases of endocarditis and demonstrates the utility of PET‐CT in identifying these foci.
Staphylococcus lugdunensis is a less common highly virulent subtype of coagulase‐negative Staphylococci (CoNS) that is more likely than other CoNS subtypes to cause rapid and destructive native valve endocarditis with a high mortality rate. Attribution of CoNS‐positive blood cultures to other subtypes without confirmation may lead to inadequate treatment and morbidity and mortality.
To cite this abstract:Rubio D, Bates J. A Subacute Presentation of Staphylococcus Lugdunensis Endocarditis. Abstract published at Hospital Medicine 2013, May 16-19, National Harbor, Md. Abstract 253. Journal of Hospital Medicine. 2013; 8 (suppl 2). https://www.shmabstracts.com/abstract/a-subacute-presentation-of-staphylococcus-lugdunensis-endocarditis/. Accessed September 18, 2019.