Duration of Colonization and Determinants of Earlier Clearance of Colonization With Methicillin-Resistant Staphylococcus aureus.

BACKGROUND: The duration of colonization and factors associated with clearance of methicillin-resistant Staphylococcus aureus (MRSA) after community-onset MRSA skin and soft-tissue infection (SSTI) remain unclear. METHODS: We conducted a prospective cohort study of patients with acute MRSA SSTI presenting to 5 adult and pediatric academic hospitals from 1 January 2010 through 31 December 2012. Index patients and household members performed self-sampling for MRSA colonization every 2 weeks for 6 months. Clearance of colonization was defined as negative MRSA surveillance cultures during 2 consecutive sampling periods. A Cox proportional hazards regression model was developed to identify determinants of clearance of colonization. RESULTS: Two hundred forty-three index patients were included. The median duration of MRSA colonization after SSTI diagnosis was 21 days (95% confidence interval [CI], 19-24), and 19.8% never cleared colonization. Treatment of the SSTI with clindamycin was associated with earlier clearance (hazard ratio [HR], 1.72; 95% CI, 1.28-2.30; P < .001). Older age (HR, 0.99; 95% CI, .98-1.00; P = .01) was associated with longer duration of colonization. There was a borderline significant association between increased number of household members colonized with MRSA and later clearance of colonization in the index patient (HR, 0.85; 95% CI, .71-1.01; P = .06). CONCLUSIONS: With a systematic, regular sampling protocol, duration of MRSA colonization was noted to be shorter than previously reported, although 19.8% of patients remained colonized at 6 months. The association between clindamycin and shorter duration of colonization after MRSA SSTI suggests a possible role for the antibiotic selected for treatment of MRSA infection.

CT angiography for safe discharge of patients with possible acute coronary syndromes.

BACKGROUND: Admission rates among patients presenting to emergency departments with possible acute coronary syndromes are high, although for most of these patients, the symptoms are ultimately found not to have a cardiac cause. Coronary computed tomographic angiography (CCTA) has a very high negative predictive value for the detection of coronary disease, but its usefulness in determining whether discharge of patients from the emergency department is safe is not well established. METHODS: We randomly assigned low-to-intermediate-risk patients presenting with possible acute coronary syndromes, in a 2:1 ratio, to undergo CCTA or to receive traditional care. Patients were enrolled at five centers in the United States. Patients older than 30 years of age with a Thrombolysis in Myocardial Infarction risk score of 0 to 2 and signs or symptoms warranting admission or testing were eligible. The primary outcome was safety, assessed in the subgroup of patients with a negative CCTA examination, with safety defined as the absence of myocardial infarction and cardiac death during the first 30 days after presentation. RESULTS: We enrolled 1370 subjects: 908 in the CCTA group and 462 in the group receiving traditional care. The baseline characteristics were similar in the two groups. Of 640 patients with a negative CCTA examination, none died or had a myocardial infarction within 30 days (0%; 95% confidence interval [CI], 0 to 0.57). As compared with patients receiving traditional care, patients in the CCTA group had a higher rate of discharge from the emergency department (49.6% vs. 22.7%; difference, 26.8 percentage points; 95% CI, 21.4 to 32.2), a shorter length of stay (median, 18.0 hours vs. 24.8 hours; P<0.001), and a higher rate of detection of coronary disease (9.0% vs. 3.5%; difference, 5.6 percentage points; 95% CI, 0 to 11.2). There was one serious adverse event in each group. CONCLUSIONS: A CCTA-based strategy for low-to-intermediate-risk patients presenting with a possible acute coronary syndrome appears to allow the safe, expedited discharge from the emergency department of many patients who would otherwise be admitted. (Funded by the Commonwealth of Pennsylvania Department of Health and the American College of Radiology Imaging Network Foundation; ClinicalTrials.gov number, NCT00933400.).

The Effect of Total Household Decolonization on Clearance of Colonization With Methicillin-Resistant Staphylococcus aureus.

OBJECTIVE To determine the impact of total household decolonization with intranasal mupirocin and chlorhexidine gluconate body wash on recurrent methicillin-resistant Staphylococcus aureus (MRSA) infection among subjects with MRSA skin and soft-tissue infection. DESIGN Three-arm nonmasked randomized controlled trial. SETTING Five academic medical centers in Southeastern Pennsylvania. PARTICIPANTS Adults and children presenting to ambulatory care settings with community-onset MRSA skin and soft-tissue infection (ie, index cases) and their household members. INTERVENTION Enrolled households were randomized to 1 of 3 intervention groups: (1) education on routine hygiene measures, (2) education plus decolonization without reminders (intranasal mupirocin ointment twice daily for 7 days and chlorhexidine gluconate on the first and last day), or (3) education plus decolonization with reminders, where subjects received daily telephone call or text message reminders. MAIN OUTCOME MEASURES Owing to small numbers of recurrent infections, this analysis focused on time to clearance of colonization in the index case. RESULTS Of 223 households, 73 were randomized to education-only, 76 to decolonization without reminders, 74 to decolonization with reminders. There was no significant difference in time to clearance of colonization between the education-only and decolonization groups (log-rank P=.768). In secondary analyses, compliance with decolonization was associated with decreased time to clearance (P=.018). CONCLUSIONS Total household decolonization did not result in decreased time to clearance of MRSA colonization among adults and children with MRSA skin and soft-tissue infection. However, subjects who were compliant with the protocol had more rapid clearance Trial registration. ClinicalTrials.gov identifier: NCT00966446 Infect Control Hosp Epidemiol 2016;1-8.

Risk factors for recurrent colonization with methicillin-resistant Staphylococcus aureus in community-dwelling adults and children.

OBJECTIVE To identify risk factors for recurrent methicillin-resistant Staphylococcus aureus (MRSA) colonization. DESIGN Prospective cohort study conducted from January 1, 2010, through December 31, 2012. SETTING Five adult and pediatric academic medical centers. PARTICIPANTS Subjects (ie, index cases) who presented with acute community-onset MRSA skin and soft-tissue infection. METHODS Index cases and all household members performed self-sampling for MRSA colonization every 2 weeks for 6 months. Clearance of colonization was defined as 2 consecutive sampling periods with negative surveillance cultures. Recurrent colonization was defined as any positive MRSA surveillance culture after clearance. Index cases with recurrent MRSA colonization were compared with those without recurrence on the basis of antibiotic exposure, household demographic characteristics, and presence of MRSA colonization in household members. RESULTS The study cohort comprised 195 index cases; recurrent MRSA colonization occurred in 85 (43.6%). Median time to recurrence was 53 days (interquartile range, 36-84 days). Treatment with clindamycin was associated with lower risk of recurrence (odds ratio, 0.52; 95% CI, 0.29-0.93). Higher percentage of household members younger than 18 was associated with increased risk of recurrence (odds ratio, 1.01; 95% CI, 1.00-1.02). The association between MRSA colonization in household members and recurrent colonization in index cases did not reach statistical significance in primary analyses. CONCLUSION A large proportion of patients initially presenting with MRSA skin and soft-tissue infection will have recurrent colonization after clearance. The reduced rate of recurrent colonization associated with clindamycin may indicate a unique role for this antibiotic in the treatment of such infection.