Stenotrophomonas maltophilia prosthetic valve endocarditis: a case report

<p>Abstract</p> <p>Introduction</p> <p><it>Stenotrophomonas maltophilia </it>is an environmental bacterium increasingly involved in nosocomial infections and resistant to most antibiotics. It is important to recognize and efficiently treat infections with this bacterium as soon as possible.</p> <p>Case presentation</p> <p>We present a case of <it>Stenotrophomonas maltophilia </it>prosthetic valve endocarditis secondary to an indwelling catheter infection. The patient was cured without surgery. We review other cases of <it>S. maltophilia </it>endocarditis from the literature and describe the peculiarities of this case.</p> <p>Conclusion</p> <p><it>S. maltophilia </it>endocarditis is a rare disease that is often hospital-acquired and related to an indwelling catheter infection. The high lethality is likely related to the intrinsic resistance of nosocomial bloodstream infections to commonly prescribed antibiotics.</p

Modeling the Spread of Methicillin-Resistant Staphylococcus aureus in Nursing Homes for Elderly

Methicillin-resistant Staphylococcus aureus (MRSA) is endemic in many hospital settings, including nursing homes. It is an important nosocomial pathogen that causes mortality and an economic burden to patients, hospitals, and the community. The epidemiology of the bacteria in nursing homes is both hospital- and community-like. Transmission occurs via hands of health care workers (HCWs) and direct contacts among residents during social activities. In this work, mathematical modeling in both deterministic and stochastic frameworks is used to study dissemination of MRSA among residents and HCWs, persistence and prevalence of MRSA in a population, and possible means of controlling the spread of this pathogen in nursing homes. The model predicts that: without strict screening and decolonization of colonized individuals at admission, MRSA may persist; decolonization of colonized residents, improving hand hygiene in both residents and HCWs, reducing the duration of contamination of HCWs, and decreasing the resident∶staff ratio are possible control strategies; the mean time that a resident remains susceptible since admission may be prolonged by screening and decolonization treatment in colonized individuals; in the stochastic framework, the total number of colonized residents varies and may increase when the admission of colonized residents, the duration of colonization, the average number of contacts among residents, or the average number of contacts that each resident requires from HCWs increases; an introduction of a colonized individual into an MRSA-free nursing home has a much higher probability of leading to a major outbreak taking off than an introduction of a contaminated HCW

Healthcare-associated pneumonia among hospitalized patients in a Korean tertiary hospital

<p>Abstract</p> <p>Background</p> <p>Healthcare-associated pneumonia (HCAP) has more similarities to nosocomial pneumonia than to community-acquired pneumonia (CAP). However, there have only been a few epidemiological studies of HCAP in South Korea. We aimed to determine the differences between HCAP and CAP in terms of clinical features, pathogens, and outcomes, and to clarify approaches for initial antibiotic management.</p> <p>Methods</p> <p>We conducted a retrospective, observational study of 527 patients with HCAP or CAP who were hospitalized at Severance Hospital in South Korea between January and December 2008.</p> <p>Results</p> <p>Of these patients, 231 (43.8%) had HCAP, and 296 (56.2%) had CAP. Potentially drug-resistant (PDR) bacteria were more frequently isolated in HCAP than CAP (12.6% vs. 4.7%; <it>P </it>= 0.001), especially in the low-risk group of the PSI classes (41.2% vs. 13.9%; <it>P </it>= 0.027). In-hospital mortality was higher for HCAP than CAP patients (28.1% vs. 10.8%, <it>P </it>< 0.001), especially in the low-risk group of PSI classes (16.4% vs. 3.1%; <it>P </it>= 0.001). Moreover, tube feeding and prior hospitalization with antibiotic treatment within 90 days of pneumonia onset were significant risk factors for PDR pathogens, with odds ratios of 14.94 (95% CI 4.62-48.31; <it>P </it>< 0.001) and 2.68 (95% CI 1.32-5.46; <it>P </it>= 0.007), respectively.</p> <p>Conclusions</p> <p>For HCAP patients with different backgrounds, various pathogens and antibiotic resistance of should be considered, and careful selection of patients requiring broad-spectrum antibiotics is important when physicians start initial antibiotic treatments.</p

Epidemiology and risk factors for Staphylococcus aureus colonization in children in the post-PCV7 era

<p>Abstract</p> <p>Background</p> <p>The incidence of community-associated methicillin-resistant <it>Staphylococcus aureus </it>(MRSA) has risen dramatically in the U.S., particularly among children. Although <it>Streptococcus pneumoniae </it>colonization has been inversely associated with <it>S. aureus </it>colonization in unvaccinated children, this and other risk factors for <it>S. aureus </it>carriage have not been assessed following widespread use of the heptavalent pneumococcal conjugate vaccine (PCV7). Our objectives were to (1) determine the prevalence of <it>S. aureus </it>and MRSA colonization in young children in the context of widespread use of PCV7; and (2) examine risk factors for <it>S. aureus </it>colonization in the post-PCV7 era, including the absence of vaccine-type <it>S. pneumoniae </it>colonization.</p> <p>Methods</p> <p>Swabs of the anterior nares (<it>S. aureus</it>) were obtained from children enrolled in an ongoing study of nasopharyngeal pneumococcal colonization of healthy children in 8 Massachusetts communities. Children 3 months to <7 years of age seen for well child or sick visits in primary care offices from 11/03–4/04 and 10/06–4/07 were enrolled. <it>S. aureus </it>was identified and antibiotic susceptibility testing was performed. Epidemiologic risk factors for <it>S. aureus </it>colonization were collected from parent surveys and chart reviews, along with data on pneumococcal colonization. Multivariate mixed model analyses were performed to identify factors associated with <it>S. aureus </it>colonization.</p> <p>Results</p> <p>Among 1,968 children, the mean age (SD) was 2.7 (1.8) years, 32% received an antibiotic in the past 2 months, 2% were colonized with PCV7 strains and 24% were colonized with non-PCV7 strains. The prevalence of <it>S. aureus </it>colonization remained stable between 2003–04 and 2006–07 (14.6% vs. 14.1%), while MRSA colonization remained low (0.2% vs. 0.9%, p = 0.09). Although absence of pneumococcal colonization was not significantly associated with <it>S. aureus </it>colonization, age (6–11 mo vs. ≥5 yrs, OR 0.39 [95% CI 0.24–0.64]; 1–1.99 yrs vs. ≥5 yrs, OR 0.35 [0.23–0.54]; 2–2.99 yrs vs. ≥5 yrs, OR 0.45 [0.28–0.73]; 3–3.99 yrs vs. ≥5 yrs, OR 0.53 [0.33–0.86]) and recent antibiotic use were significant predictors in multivariate models.</p> <p>Conclusion</p> <p>In Massachusetts, <it>S. aureus </it>and MRSA colonization remained stable from 2003–04 to 2006–07 among children <7 years despite widespread use of pneumococcal conjugate vaccine. <it>S. aureus </it>nasal colonization varies by age and is inversely correlated with recent antibiotic use.</p