Therapy and Outcome of Staphylococcus aureus Infections of Intracorporeal Ventricular Assist Devices

Abstract

Infection of the driveline or pump pocket is a common complication in patients with ventricular assist devices (VADs) and Staphylococcus aureus is the main pathogen causing such infections. Limited evidence is currently available to guide the choice of antibiotic therapy and the duration of treatment in these patients. Patients at the University Medical Center Utrecht who developed a VAD‐related S. aureus infection between 2007 and 2016 were retrospectively assessed. Blood culture isolates were typed by whole genome sequencing to differentiate between relapses and reinfections, and to determine whether antibiotic therapy had led to acquisition of resistance mutations. Twenty‐eight patients had S. aureus VAD infections. Ten of these patients also suffered S. aureus bacteremia. Discontinuation of antibiotic therapy was followed by relapse in 50% of the patients without prior S. aureus bacteremia and in 80% of patients with bacteremia. Oral cephalexin could ultimately suppress the infection for the duration of follow‐up in 8/8 patients without S. aureus bacteremia and in 3/6 patients with S. aureus bacteremia. Clindamycin failed as suppressive therapy in 4/4 patients. Cephalexin appears an adequate choice for antibiotic suppression of VAD infections with methicillin‐susceptible S. aureus. In patients without systemic symptoms, it may be justified to attempt to stop therapy after treatment of the acute infection, but antibiotic suppression until heart transplant seems indicated in patients with S. aureus bacteremia.

Efficacy and safety of chronic antimicrobial suppression therapy for left ventricular assist device driveline infections: A single‐center descriptive experience

“…Consistent with prior studies on CAS therapy, 5,13,14 we found a high proportion of patients experiencing treatment failures while on antimicrobial regimens which offered adequate coverage for the inciting pathogens. Neinaber et al (2013) reported that 29% of all LVAD patients receiving suppressive therapy for local or bloodstream infections experienced relapses, 5 and Jennings et al (2013) found that parenteral antibiotics were required to address failed PO regimens in 31% of CAS therapy patients 13 .…”

“…have been demonstrated to be common causes of DLIs in other studies 7,17 . A high rate of relapse for S aureus LVAD infections has also been reported 14 . For our patients with relapses while on CAS therapy, 89% were caused by staphylococcal spp., clearly demonstrating the morbidity of these infections.…”

“…Overall, the use of CAS therapy for LVAD DLIs is not well characterized, and the few existing recommendations are not based on prospective studies or randomized controlled trials. 1,5,14 Some authors recommend initiating CAS therapy based on whether previous bacteremia occurred 14 whereas other authors only recommend suppression when deeper sites like the pump pocket or cannula are involved. 5 A recent retrospective study found that 72% of all patients who survived their initial LVAD infections received suppressive antimicrobials, 20 demonstrating the widespread use of this treatment strategy despite a lack of clear guidelines.…”

“…12 Despite over a decade of experience, 1 there is a dearth of information concerning chronic antimicrobial suppression (CAS) therapy for LVAD patients with DLIs. Only three retrospective studies have specifically focused on this topic, 10,13,14 and there are conflicting views about whether or not CAS therapy is indicated for patients with DLIs. 1,5 In order to address the literature gap surrounding this topic, we conducted a retrospective review study at our institution in order to characterize the efficacy and safety of CAS therapy for patients with DLIs.…”

Artificial Organs 2018: A Year in Review

“…Miquel B. Ekkelenkamp et al of University Medical Center Utrecht, Utrecht, The Netherlands, investigated the therapy and outcomes Staphylococcus aureus infections of intracorporeal ventricular assist devices (VADs). Patients at their center who developed a VAD‐related S. aureus infection were retrospectively assessed.…”