Risk Factors for Recurrent Colonization With Methicillin-ResistantStaphylococcus aureusin Community-Dwelling Adults and Children

Abstract

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.

Factors associated with persistent colonisation with methicillin-resistantStaphylococcus aureus

“…Treatment of the initial MRSA SSTI with clindamycin was significantly associated with decreased risk of persistent MRSA colonisation. We found the same association between clindamycin and earlier clearance of MRSA colonisation [9] as well as decreased risk of recurrent MRSA colonisation [15]. One small study noted that patients with staphylococcal skin infections treated with clindamycin for 3 months resulted in recurrent abscesses in 2 of 11 patients as compared with 7 of 11 patients who received placebo [29].…”

Genome sequencing reveals strain dynamics of methicillin-resistant Staphylococcus aureus in the same household in the context of clinical disease in a person and a dog

“…The scenario described in this report represents one explanation for observed failure of household-wide decolonization protocols to eradicate S. aureus carriage from index cases (Fritz et al 2012; Cluzet et al 2015a) and is unique in that it neither implicates the home environment nor the pet dog in re-colonization of the index patient following successful treatment. While future case assessments and research studies should include multiple evaluations of home environmental contamination and companion animal carriage over time to capture the potentially dynamic nature of intra-household transmission, attention to community sources outside the home may be necessary to understand drivers of recurrent colonization or infection.…”

“…The household, which consisted of the index patient and a white female household member in her 30s, enrolled in the Epidemiology and Prevention of MRSA Transmission in the Community trial (NCT00966446) in July 2012 (Cluzet et al 2015a; Cluzet et al 2015b). Four weeks after the index patient’s MRSA SSTI diagnosis, the two people in the household were randomized at the baseline study visit to receive one week of twice-daily nasal mupirocin treatment and two body washes with 4% chlorhexidine gluconate (Hibiclens®, Mölnlycke Health Care, Norcross, Georgia).…”

Focus on optimization of early antimicrobial therapy in ICU-acquired infections

“…Around 20 % of MRSA-infected patients never clear their colonization, and older age has been reported to be associated with longer duration of MRSA colonization [2]. Early caloric negative-energy balance is an independent determinant of MRSA colonization and of late-onset infection in mechanically ventilated patients.…”