Pre-cesarean Staphylococcus aureus nasal screening and decolonization: a prospective randomized controlled trial

Skin and mucous membranes colonisation with Staphylococcus aureus or MRSA as a risk factor for surgical site infections in elective Caesarean Section

The purpose of this study was to determine if skin and mucous membrane colonisation with Staphylococcus aureus (S. aureus) and methicillin-resistant Staphylococcus aureus (MRSA) increases the incidence of surgical site infection (SSI) post-elective Caesarean Sections. A prospective study was conducted at a major centre in Jordan, involving 127 patients who underwent elective Caesarean Section surgeries during 2019. Participants were screened for skin and mucous membranes colonisation for S. aureus preoperatively and were followed for 90 days for any signs of SSI. The screening sites were on three parts of the patients' bodies; nose, throat, and groyne. The total SSI incidence was 18.9%. Among participants with SSI; 66.7% had a superficial infection and 33.3% had deep tissue infection. Skin and mucous membrane colonisation was positive in 42 participants (33.1%) in one of the three screening sites. Participants with positive skin and mucous membrane colonisation were found to have SSI incidence 2.43 times more than the non-colonised participants (Fisher's Exact test = 3.832, p = .05, CI: 0.098-6.02). Participants with S. aureus skin and mucous membranes colonisation were significantly 2.94 times with more SSI incidence than those who were not colonised (Fisher's Exact test = 5.485, p = .02, CI: 1.164-7.439). Skin and mucous membrane colonisation was found to increase the incidence of SSI. More attention should be performed to screen for skin and mucous membranes colonisation and subsequent selective skin decolonisation to decrease SSI incidence.IMPACT STATEMENTWhat is already known on this subject? Surgical site infection (SSI) is a challenge that increases the costs of health care. Surgical site infection is associated with high costs mainly due to the increase in the length of hospital stay. Skin screening for S. aureus or MRSA colonisation was found to be important for selective skin decolonisation using appropriate antiseptic preparation and preoperative antibiotic prophylaxis.What do the results of this study add? The incidence of SSI in the colonised group was found to be 2.43 times higher than in the non-colonised group.What are the implications of these findings for clinical practice and/or further research? Screening for colonisation and subsequent selective skin decolonisation should be a part of SSI prevention policies.

Nasal decolonization of Staphylococcus aureus and the risk of surgical site infection after surgery: a meta-analysis

Aim

To assess the effects of nasal decontamination on preventing surgical site infections (SSIs) in people who are Staphylococcus aureus carriers undergoing different types of surgeries and diverse measures of decolonization.

Methods

Relevant randomized controlled trials (RCTs) were identified through systematic searches of the PubMed, Embase, Web of science, and the Cochrane Library databases. The risk ratios (RRs) and 95% confidence intervals (CIs) were calculated and the effects model was chosen according to the heterogeneity. Subgroup analyses were performed according to different types of surgeries and measures of decolonization that Staphylococcus aureus carriers were applied.

Results

Twenty RCTs published between 1996 and 2019 involving 10,526 patients were included. Pooled results showed that the overall SSIs and pulmonary surgery SSIs presented with a statistical difference in measures of nasal decontamination (RR = 0.59 and 0.47, respectively, both p < 0.01). However, the associations between nasal decolonization and increased risks of SSIs in orthopedics surgery or cardiovascular surgery remained insignificant in studies. As for the diverse measures of nasal decontamination, 50% used mupirocin, 15% used chlorhexidine, 30% used different types of antimicrobial drugs, and 5% use others. The SSIs rate were decreased after chlorhexidine (RR = 0.474, 95% CI 0.259–0.864), while no significant difference was shown in the use of mupirocin (RR = 0.871, 95% CI 0.544–1.394).

Conclusion

It seems that nasal decolonization of Staphylococcus aureus may be associated with a reduction of SSIs in these patients, especially in patients who have been administered by pulmonary surgeries or treated with chlorhexidine.

Staphylococcus aureus nasal decolonization strategies: a review

Introduction: Staphylococcus aureus (S. aureus) infections are associated with increased morbidity, mortality and health-care costs. Persistent nasal carriage of S. aureus found in 10-30% of the general population, constitutes a risk factor for these infections. Nasal decolonization is one of the used strategies to prevent this risk in some situations. Areas covered: Mupirocin nasal ointment has been used for the nasal decolonization and prevention of staphylococcal infections in various settings like surgeries. However, rising rates of resistance to mupirocin require the development of new decolonization agents. In this review, we will discuss mupirocin, its origins, studies that proved its efficacy and the associated resistance, as well as other decolonization agents under investigation. Expert opinion: As some limitations exist to mupirocin use, further research for alternatives is encouraged. Some old approved antiseptics (chlorhexidine, povidone-iodine) or antibiotics (rifampicin, bacitracin) have been investigated for their efficacy in this indication. Other new agents (tea tree oil, retapamulin, LTX-109, XF-73, phages, lysostaphin, squalamine analogues, etc.) are being studied. Some of them are still in preclinical phases, and others have reached clinical trials, but further research is needed. Special interest should be given to single dose decolonization strategies and to molecules that do not select resistant strains.

Nasal decontamination for the prevention of surgical site infection in Staphylococcus aureus carriers

BACKGROUND

Surgical site infection rates in the month following surgery vary from 1% to 5%. Due to the large number of surgical procedures conducted annually, the costs of these surgical site infections (SSIs) can be considerable in financial and social terms. Nasal decontamination using antibiotics or antiseptics is performed to reduce the risk of SSIs by preventing organisms from the nasal cavity being transferred to the skin where a surgical incision will be made. Staphylococcus aureus (S aureus) colonises the nasal cavity and skin of carriers and can cause infection in open or unhealed surgical wounds. S aureus is the leading nosocomial (hospital-acquired) pathogen in hospitals worldwide. The potential effectiveness of nasal decontamination of S aureus is thought to be dependent on both the antibiotic/antiseptic used and the dose of application; however, it is unclear whether nasal decontamination actually reduces postoperative wound infection in S aureus carriers.

OBJECTIVES

To assess the effects of nasal decontamination on preventing surgical site infections (SSIs) in people who are S aureus carriers undergoing surgery.

SEARCH METHODS

In September 2016 we searched the Cochrane Wounds Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library), Ovid MEDLINE, Ovid MEDLINE (In-Process & Other Non-Indexed Citations), Ovid Embase, and EBSCO CINAHL Plus. We also searched three clinical trial registries and the references of included studies and relevant systematic reviews. There were no restrictions based on language, date of publication or study setting.

SELECTION CRITERIA

Randomised controlled trials (RCTs) which enrolled S aureus carriers with any type of surgery and assessed the use of nasal decontamination with antiseptic/antibiotic properties were included in the review.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, data extraction, risk of bias assessment and GRADE assessment.

MAIN RESULTS

We located two studies (291 participants) for inclusion in this review. The trials were clinically heterogeneous with differences in duration of follow-up, and nasal decontamination regimens. One study compared mupirocin (2% contained in a base of polyethylene glycol 400 and polyethylene glycol 3350) with a placebo in elective cardiac surgery patients; and one study compared Anerdian (iodine 0.45% to 0.57% (W/V), chlorhexidine acetate 0.09% to 0.11% (W/V)) with no treatment also in cardiac surgery patients. The trials reported limited outcome data on SSI, adverse events and secondary outcomes (e.g. S aureus SSI, mortality). Mupirocin compared with placeboThis study found no clear difference in SSI risk following use of mupirocin compared with placebo (1 trial, 257 participants); risk ratio (RR) 1.60, 95% confidence interval (CI) 0.79 to 3.25 based on 18/130 events in the mupirocin group and 11/127 in the control group; low-certainty evidence (downgraded twice due to imprecision). Anerdian compared with no treatmentIt is uncertain whether there is a difference in SSI risk following treatment with Anerdian compared with no treatment (1 trial, 34 participants); RR 0.89, 95% CI 0.06 to 13.08 based on 1/18 events in the Anerdian group and 1/16 in the control group; very low certainty evidence (downgraded twice due to imprecision and once due to risk of bias).

AUTHORS' CONCLUSIONS

There is currently limited rigorous RCT evidence available regarding the clinical effectiveness of nasal decontamination in the prevention of SSI. This limitation is specific to the focused question our review addresses, looking at nasal decontamination as a single intervention in participants undergoing surgery who are known S aureus carriers. We were only able to identify two studies that met the inclusion criteria for this review and one of these was very small and poorly reported. The potential benefits and harms of using decontamination for the prevention of SSI in this group of people remain uncertain.