Nonstaphylococcal infections of cardiac implantable electronic devices

Abstract

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.