Infections of cardiac implantable electronic devices: a retrospective multicenter observational study.

Infections of cardiac implantable electronic devices (CIED) can cause significant morbidity, mortality, and financial burden. Although staphylococcal organisms account for most infections of these cardiac devices, approximately 20% of all CIED-related infections are caused by non-Staphylococcus species. Herein we describe and compare the demographics, clinical presentation, and outcomes of Staphylococcus aureus and non-staphylococcal infections of CIED.We performed a retrospective, multicenter, observational study of patients from 4 academic hospitals in Houston between 2002 and 2009. All 80 identified non-staphylococcal CIED-related infections were matched, at a 1:1 ratio, to S. aureus infections.Although the demographics and general comorbidities in the 2 study groups were relatively similar, the S. aureus group had a higher proportion of patients with coronary artery disease, diabetes mellitus, and end-stage renal disease. Additionally, 81% of S. aureus compared with only 48.5% of the non-staphylococcal CIED-related infections were health care-associated (p < 0.001). Furthermore, when compared to non-staphylococcal infections, the S. aureus group had more indwelling intravascular foreign material (p < 0.001), more rapid clinical progression (p < 0.001), and overall worse clinical presentation (p < 0.001). However, after stratifying by clinical presentation, the mortality rates in the 2 groups were similar (p = 0.45).Since approximately one-fifth of all CIED-related infections are caused by non-staphylococcal organisms, and untimely antibiotic treatment can result in serious complications, it may be prudent to broaden empiric antimicrobial therapy to cover both Gram-positive and -negative bacteria, until the causative organism is identified.

Nonstaphylococcal infections of cardiac implantable electronic devices.

BACKGROUND: Along with the rising use of cardiac implantable electronic devices (CIEDs), there has been a disproportional increase in the number of infections of such devices. Little is known about nonstaphylococcal CIED-related infections, which make up approximately 10% to 30% of all CIED infections. METHODS AND RESULTS: A retrospective review of hospital records of patients admitted with a CIED-related infection was conducted in 4 academic hospitals in Houston, Tex, between 2002 and 2009. Of the 504 identified patients with CIED-related infection, 80 (16%) had a nonstaphylococcal infection and were the focus of this study. The mean duration of CIED placement before infection was 109+/-27 weeks, whereas 44% had their device previously manipulated within a mean of 29.5+/-6 weeks. The mean duration of clinical symptoms before admission was 48+/-12.8 days. Furthermore, 13 patients (16%) presented with CIED-related endocarditis. Although not described in prior reports, we identified 3 definite and 2 suspected cases of secondary Gram-negative bacteria seeding of the CIED. Inappropriate antimicrobial coverage was provided in approximately 50% of the cases with a mean period of 2.1 days. The overall mortality rate was 4%. CONCLUSIONS: Nonstaphylococcal CIED-related infections are prevalent and diverse with a relatively low virulence and mortality rate. Because nonstaphylococcal organisms are capable of secondarily seeding the CIED, a high suspicion for CIED-related infection is warranted in patients with bloodstream infection. In patients with suspected CIED infection, adequate Gram-positive and Gram-negative antibacterial coverage should be administered until microbiological data become available.