A 63‐year‐old woman with history of bariatric surgery, gastroparesis, daily emesis, on parenteral nutrition, aortic insufficiency, and mitral regurgitation (presumed secondary to past use of anorectic drugs) was admitted with fever, lethargy, orthostatic hypotension, tachycardia, and an old left lower sternal border III/VI systolic murmur. She refused placement of central venous and Foley catheters. Data showed mild leukocytosis, thrombocytopenia, and chronic anemia; bicarbonate was 20 mEq/L, lactate 3.3 mmol/L, and creatinine 0.9 mg/dL. Blood cultures were drawn, and vancomycin and piperacillin/tazobactam were administered. In 2/2 blood culture bottles grew coagulase‐negative staphylococci. Transthoracic echocardiography compared with 3 years prior showed mild progression of aortic stenosis and mitral and aortic regurgitation without vegetations. She continued to spike fevers and developed moderate tachypnea without shortness of breath. She repeatedly refused collection of an arterial blood gas (ABG) and a transesophageal echocardiogram, but despite negative repeat blood cultures was continued on vancomycin and piperacillin/ tazobactam for presumed nosocomial and aspiration pneumonia. On hospital day 12, her respiratory rate was 36, and she was hemodynamically stable with O2 saturation of 100% on room air. She finally agreed to an ABG, which demonstrated pH 7.14, pCO2 11 mm Hg, pO2 192 mm Hg, lactate 11.5 mmol/L. She then went into pulseless electrical activity arrest and died. An autopsy revealed an aortic valve mostly destroyed, with fibrous thickening of the remaining cusps, and a 3‐cm vegetation that bridged across and filled the aortic lumen, invading through the interatrial septum above the tricuspid valve with gram‐positive cocci within the vegetation.
Although coagulase‐negative staphylococci are often considered contaminants, they are responsible for many cases of prosthetic valve endocarditis but <5% of native valve endocarditis. Although relatively avirulent, coagulase‐negative Staphylococcus native‐valve endocarditis can lead to heart failure and death similar to patients with endocarditis from Staphylococcus aureus. Those rare patients who did acquire native‐valve endocarditis from coagulase‐negative staphylococci did so out of the hospital, and preexisting valvular disease appears to be a major risk factor. To the best of our knowledge, there is no documented direct link between history of being on anorectic drugs and endocarditis. Infection with coagulase‐negative staphylococci can also extend from the valve leaflet into adjacent tissue.
Hospitalists increasingly care for patients with indwelling catheters and get blood culture results positive for coagulase‐negative Staphylococcus. The diagnosis of native‐valve endocarditis from coagulase‐negative Staphylococcus needs to be considered when bacteremia with these organisms is encountered in a patient with preexisting valvulo‐pathies. One must be vigilant that this is not simply a catheter‐associated bloodstream infection or a contaminant, but a true coagulase‐negative staphylococci endocarditis.
M. Krivopal ‐ none
To cite this abstract:Krivopal M. Cupid's Arrow: Real or a Contaminant?. Abstract published at Hospital Medicine 2011, May 10-13, Dallas, Texas. Abstract 321. Journal of Hospital Medicine. 2011; 6 (suppl 2). https://www.shmabstracts.com/abstract/cupids-arrow-real-or-a-contaminant/. Accessed October 20, 2019.