Baddour, Larry M.

Background— The American Heart Association published updated guidelines for infective endocarditis (IE) prevention in 2007 that markedly restricted the use of antibiotic prophylaxis in certain at-risk patients undergoing dental and other invasive procedures. The incidence of IE caused by viridans group streptococci (VGS) in the United States after publication of the 2007 American Heart Association guidelines has not been reported. Methods and Results— We performed a population-based review of all definite or possible cases of VGS-IE using the Rochester Epidemiology Project of Olmsted County, Minnesota. Patient demographics and microbiological data were collected for all VGS-IE cases diagnosed from January 1, 1999, through December 31, 2010. We also examined the Nationwide Inpatient Sample hospital discharge database to determine the number of VGS-IE cases included between 1999 and 2009. We identified 22 cases with VGS-IE in Olmsted County over the 12-year study period. Rates of incidence (per 100 000 person-years) during time intervals of 1999–2002, 2003–2006, and 2007–2010 were 3.19 (95% confidence interval, 1.20–5.17), 2.48 (95% confidence interval, 0.85–4.10), and 0.77 (95% confidence interval, 0.00–1.64), respectively ( P =0.061 from Poisson regression). The number of hospital discharges with a VGS-IE diagnosis in the Nationwide Inpatient Sample database during 1999–2002, 2003–2006, and 2007–2009 ranged between 15 318 to 15 938, 16 214 to 17 433, and 14 728 to 15 479, respectively. Conclusions— On the basis of data complete through 2010, there has been no perceivable increase in the incidence of VGS-IE in Olmsted County, Minnesota, since the publication of the 2007 American Heart Association endocarditis prevention guidelines.

SummaryBackgroundCommunity‐acquired Clostridium difficile infection (CA‐CDI) is an increasingly appreciated condition. It is being described in populations lacking traditional predisposing factors that have been previously considered at low‐risk for this infection. As most studies of CDI are hospital‐based, outcomes in these patients are not well known.AimTo examine outcomes and their predictors in patients with CA‐CDI.MethodsA sub‐group analysis of a population‐based epidemiological study of CDI in Olmsted county, Minnesota from 1991–2005 was performed. Data regarding outcomes, including severity, treatment response, need for hospitalisation and recurrence were analysed.ResultsOf 157 CA‐CDI cases, the median age was 50 years and 75.3% were female. Among all CA‐CDI cases, 40% required hospitalisation, 20% had severe and 4.4% had severe‐complicated infection, 20% had treatment failure and 28% had recurrent CDI. Patients who required hospitalisation were significantly older (64 years vs. 44 years, P < 0.001), more likely to have severe disease (33.3% vs. 11.7%, P = 0.001), and had higher mean Charlson comorbidity index scores (2.06 vs. 0.84, P = 0.001). They had similar treatment failure and recurrence rates as patients who did not require hospitalisation.ConclusionsCommunity‐acquired Clostridium difficile infection can be associated with complications and poor outcomes, including hospitalisation and severe Clostridium difficile infection. As the incidence of community‐acquired Clostridium difficile infection increases, clinicians should be aware of risk factors (increasing age, comorbid conditions and disease severity) that predict the need for hospitalisation and complications in patients with community‐acquired Clostridium difficile infection.

Background— Infection is a serious complication of cardiovascular implantable electronic device (CIED) placement and requires device removal for attempted cure. Methods and Results— We studied the rate, risk factors, and outcomes of CIED infection in 74 consecutive patients with bacteremia caused by Gram-positive cocci (GPC) other than Staphylococcus aureus between 2001 and 2007. CIED infection was defined as the presence of signs of infection at the generator site, lead vegetations seen on echocardiography, or microbiological growth from device cultures. Twenty-two (30%) of 74 patients with non– S aureus GPC bacteremia had CIED infections. Coagulase-negative staphylococci (CoNS) accounted for 73% of CIED infections. The rate of CIED infection in patients with CoNS bacteremia was almost 2-fold that of non-CoNS GPC bacteremia (36% versus 20%, P =0.13). The number of leads, the presence of abandoned leads, and prior generator replacement were associated with CIED infection. Among 33 patients without identifiable CIED infection at initial evaluation who did not undergo device removal, 5 (15%) had relapsing bacteremia within 12 weeks of completing antibiotic therapy. CoNS accounted for all relapses, and none had evidence of CIED infection at relapse. Conclusions— Patients with a CIED and bacteremia caused by GPC other than S aureus frequently had evidence of underlying CIED infection on clinical evaluation that included transesophageal echocardiography. This was particularly true among those with CoNS bacteremia. No evidence of underlying CIED infections was identified in the subgroup of patients who did not have manifestations of CIED infection on initial evaluation but subsequently had relapsing bacteremia caused by CoNS.