Topical Decolonization Does Not Eradicate the Skin Microbiota of Community-Dwelling or Hospitalized Adults

Abstract

Topical antimicrobials are often employed for decolonization and infection prevention and may alter the endogenous microbiota of the skin. The objective of this study was to compare the microbial communities and levels of richness and diversity in community-dwelling subjects and intensive care unit (ICU) patients before and after the use of topical decolonization protocols. We enrolled 15 adults at risk for Staphylococcus aureus infection. Community subjects (n ‫؍‬ 8) underwent a 5-day decolonization protocol (twice daily intranasal mupirocin and daily dilute bleach-water baths), and ICU patients (n ‫؍‬ 7) received daily chlorhexidine baths. Swab samples were collected from 5 anatomic sites immediately before and again after decolonization. A variety of culture media and incubation environments were used to recover bacteria and fungi; isolates were identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry. Overall, 174 unique organisms were recovered. Unique communities of organisms were recovered from the community-dwelling and hospitalized cohorts. In the communitydwelling cohort, microbial richness and diversity did not differ significantly between collections across time points, although the number of body sites colonized with S. aureus decreased significantly over time (P ‫؍‬ 0.004). Within the hospitalized cohort, richness and diversity decreased over time compared to those for the enrollment sampling (from enrollment to final sampling, P ‫؍‬ 0.01 for both richness and diversity). Topical antimicrobials reduced the burden of S. aureus while preserving other components of the skin and nasal microbiota. N osocomial infections pose significant clinical and financial burdens to patients and health care systems (1, 2). Colonization with potential pathogens serves as an endogenous source of infection (e.g., central line-associated bloodstream infection with Staphylococcus aureus) (3). For hospitalized patients, particularly those in intensive care units (ICUs), decolonization with topical antimicrobials, including chlorhexidine and/or mupirocin, has been demonstrated to reduce the acquisition of antibiotic-resistant microorganisms and the incidence of hospital-acquired infections (4-6). While decolonization has traditionally been employed in health care settings, the emergence of methicillinresistant S. aureus (MRSA) in the community and the resultant epidemic of skin and soft tissue infections (SSTIs) have led to the extrapolation of decolonization to outpatients to prevent recurrent SSTIs (7-10). As these broad-spectrum therapies are not pathogen specific (e.g., for MRSA or Enterobacteriaceae), these agents may suppress or eliminate other organisms on the skin and nasal mucosa, thereby potentially disrupting the balance of the microbiota, an important component of host defense against pathogenic organisms (11, 12). Indeed, this dysbiosis has been demonstrated for the intestinal microbiota following administration of oral antibiotics (13,14).Culture-independent molecular meth...

Topical Antimicrobial Treatments Can Elicit Shifts to Resident Skin Bacterial Communities and Reduce Colonization by Staphylococcus aureus Competitors

“…Indeed, our ability to detect differences in TAO-treated mice within 1 day of treatment provides strong evidence to the contrary. Others have also reported similar community responses to both decolonization protocols (42) and mild and antibacterial soaps (43), further validating this assertion.…”

Cutibacterium acnes phylotypes diversity loss: a trigger for skin inflammatory process

“…These data also support the idea that skin microbiota may be a crucial target in acne and thus, the interest of a therapeutically approach by topical modulators of microbiota both for maintaining and restoring the cutaneous diversity of C. acnes phylotypes. It also confirms that topical macrolides should be abandoned as they may participate to the loss of microbiota diversity, in addition to increase the bacterial resistance not only for C. acnes but also Staphylococcus epidermidis , S. aureus and Streptococcus …”

“…It also confirms that topical macrolides should be abandoned as they may participate to the loss of microbiota diversity, in addition to increase the bacterial resistance not only for C. acnes but also Staphylococcus epidermidis, S. aureus and Streptococcus. 24,[49][50][51][52][53]…”

Bacterial Infections in Neonates Following Mupirocin-Based MRSA Decolonization: A Multicenter Cohort Study

“…27 However, a recent study of 15 adults, both outpatient and ICU patients, found that microbial richness did not differ pre- versus post-mupirocin treatment, while S. aureus body site colonization decreased over time. 28 The assessment of this issue in neonates remains important as it is possible mupirocin-driven dysbiosis is occurring but is undetectable when clinical infection is the outcome of interest. This may be particularly relevant as neonatal microbiomes are evolving and perturbations may impact its long-term composition and stability.…”