Effect of mupirocin on nasal carriage of Staphylococcus aureus

Eradication of community-onset Methicillin-resistant Staphylococcus aureus carriage: a narrative review

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) colonization increases infection risk in both patients and healthy individuals. Decolonization therapy has been proven to reduce S. aureus infections, but data on the effectiveness of individual decolonization strategies in community-onset MRSA carriage are scarce.

OBJECTIVES

The aim of this narrative review was to summarize the evidence on strategies for the elimination of MRSA colonization in community-onset MRSA carriers.

SOURCES

PubMed database was searched for studies on MRSA eradication, from inception to July 2023.

CONTENT

Topical therapy is proven to be effective in nasal-only carriage and in temporary load reduction. Mupirocin nasal ointment in combination with chlorhexidine body wash is highly effective in nasal-only MRSA carriers in the community as well. In patients with extra-nasal colonization, addition of orally administered antibiotics likely increases success rates compared with topical therapy alone. Studies on systemic treatment of extra-nasal MRSA decolonization are subject to a high heterogeneity of antimicrobial agents, treatment duration, and control groups. The majority of evidence supports the use of a combination of topical therapy with rifampin and another antimicrobial agent. Decolonization treatment with probiotics is a promising novel non-antibiotic strategy. However, achieving long-term decolonization is more likely in countries with low MRSA prevalence, given the risk of recolonization in a context of high MRSA prevalence.

IMPLICATIONS

The decision to pursue community-onset MRSA eradication treatment in the individual patient should be based on the combination of the treatment objective (short-term bacterial load reduction in health care settings vs. long-term eradication in community settings), and the likelihood of successful decolonization. The latter is influenced by both individual risk factors for treatment failure, and the risk of recolonization. The addition of a combination of systemic antibiotics is rational for extra-nasal long-term decolonization. To determine the most effective systemic antimicrobial agents in MRSA decolonization, more research is needed.

Modifiable Preoperative Risk Factors to Mitigate Postoperative Site Infection Following Pediatric Gastrostomy

PURPOSE

There are limited studies assessing modifiable preoperative risk factors for pediatric laparoscopic gastrostomy tubes (LGT) and percutaneous endoscopic gastrostomy (PEG) tubes. We sought to evaluate the effect of demographics and surgical/infectious history on the superficial infection rate following gastrostomy tube (GT) placement.

METHODS

After IRB approval, we conducted a single-institution retrospective cohort study from 2015 to 2021 of pediatric patients undergoing LGT or PEG tube. The primary outcome was cellulitis or abscess formation within 30-days and 90-days postoperatively. Statistical analyses were performed with t-tests, Chi-squared, and logistic regression(p ≤ 0.05).

RESULTS

There were 382 patients, with 181 (47%) LGT and 201 (53%) PEGs. LGT patients were younger (5.9 vs. 12.3 months, p < 0.001) and more likely to be admitted to the neonatal or cardiac intensive care unit prior to their GT. There were similar rates of prior surgical intervention (58% vs. 66%, p = 0.29) and previous infection (37% vs. 38%, p = 0.87) in both LGT and PEG patients. Within 30-days postoperatively, LGT patients had a higher superficial infection rate (12% vs. 6%, p = 0.04). On multivariate regression, Black race (Odds Ratio 0.10, p = 0.03) was protective and prior Staphylococcus colonization (OR 2.35, p = 0.04) increased the odds of infection. In those patients colonized with Staphylococcus, 21% developed a superficial site infection compared to 9% in those not colonized (p = 0.01).

CONCLUSION

These data suggest prior Staphylococcus colonization is a significant risk factor for superficial infection following GT. Further work into preoperative decolonization strategies may provide an avenue to decrease the high infection rate in this common pediatric procedure.

LEVEL OF EVIDENCE

Level III.

Elimination of Nasal Carriage ofStaphylococcus aureusin Hemodialysis Patients

Objective:

To study the efficacy of mupirocin for the elimination of nasal carriage ofStaphylococcus aureusin hemodialysis patients.

Design:

The efficacy of mupirocin was studied in a prospectively followed cohort. The effect of this intervention on the rate ofS aureusbacteremia was evaluated using a historic control group.

Setting:

Patients on the hemodialysis unit of the University Hospital Rotterdam, a tertiary referral center.

Patients:

The study group consisted of consecutive patients on hemodialysis from February 1, 1992, until November 1, 1993. They were screened by taking nasal cultures monthly during their time on hemodialysis. IfS aureuswas isolated, treatment with mupirocin nasal ointment was initiated. The control group consisted of patients treated on the same hemodialysis unit from January 1, 1990, until January 1, 1992.

Results:

The study group consisted of 226 patients, of whom 172 were evaluated to determine the efficacy of mupirocin. Sixty-seven (39%) were identified as nasal carriers. Following the initial treatment, 66 nasal cultures (98.5%) became negative. After 3 months and 6 months, respectively, 63 (94%) and 61 (91%) of the treated carriers had negative cultures. The rate of bacteremia (defined as the number of episodes of5 aureusbacteremia per patient-year on hemodialysis) was significantly lower among the 226 patients in the study group (0.04 per patient-year) than among the 273 patients in the control group (0.25 per patient year;P<.001). Development of resistance and adverse effects were not observed.

Conclusions:

Mupirocin nasal ointment effectively eliminates nasal carriage of5 aureusin patients on hemodialysis. This was associated with a significant reduction of the incidence of5 aureusbacteremia, as compared to historic controls.

Double-blind prospective randomized study comparing topical mupirocin and placebo for the prevention of infection associated with central venous catheters

OBJECTIVE

To compare the incidence of exit site colonization, local catheter-related infection and catheter-related bacteremia in patients randomized to receive either topical 2% mupirocin or placebo at the catheter exit site.

PATIENTS AND METHODS

Patients requiring central venous catheters for more than three days were randomized to receive in a double-blind fashion either topical mupirocin or an identical placebo at the exit site three times weekly at the time of dressing change. Insertion, site care and removal of catheters were standardized. Serial semiquantitataive cultures of the skin at the catheter insertion site were performed using a sterile 25 cm(2) template. The distal and proximal catheter segments were cultured using a standardized semiquantitative technique, and any suspect catheter-related bacteremia was investigated with two sets of peripheral blood cultures, a 10 mL sample of infusate and clinical assessment. Both univariate and multivariate analyses were conducted on individual risk factors to determine factors that might influence the outcomes of local or systemic catheter-related infection.

RESULTS

Local catheter-related infection (defined as more than 15 colony forming units [cfu] on culture of the proximal or distal catheter segment) occurred in six of 57 (10.5%) in the mupirocin group versus 18 of 69 (26%) in the placebo group (P<0.05) for the distal catheter segments and in one of 40 (2.5%) versus 13 of 47 (27.6%) for the proximal segments in the mupirocin and placebo groups (P<0.006), respectively. Catheter-related bacteremia occurred in one of 57 (1.8%) of the mupirocin group but in five of 69 (7.2%) of the placebo group (P=0.15). Stepwise logistic regression revealed that cutaneous colonization at the insertion site of at least 10(3) cfu/mL/25 cm(2) (OR 2.6; CI 1.0 to 6.9) and the use of placebo (OR 3.3; CI 1.2 to 9.0) were significant factors predicting local catheter-related infection; whereas mupirocin was associated with reciprocal protective effect (OR 0.3; 95% CI 0.1 to 0.8).

CONCLUSIONS

These findings suggest that patients receiving topical mupirocin at the exit site for long term central venous catheters have significantly less local catheter-related infection, and there is a trend towards less catheter-related bacteremia.

New strategies for the use of mupirocin for the prevention of serious infection

Nasal mupirocin has an important role to play in the prevention of Staphylococcus aureus infection by eliminating nasal carriage of this organism. Indeed, in many countries nasal mupirocin is one of the mainstays for controlling outbreaks of methicillin-resistant S. aureus. Eradication of nasal S. aureus with mupirocin has been shown to be effective in preventing postoperative infections in patients undergoing cardiothoracic surgery and in preventing exit-site infections in patients undergoing haemodialysis. It has been proposed that the use of mupirocin should be extended to other situations, such as the prevention of postoperative infections in patients undergoing implant surgery and the prevention of bacteraemias in high-risk patients. Clinical trials are needed to establish the efficacy of mupirocin in these situations. Both low-level and high-level resistance have been reported during treatment with nasal mupirocin. Low-level resistance does not represent a significant clinical problem but high-level resistance resulting from indiscriminate use may give grounds for concern. Further review of these issues is required. As with any antibiotic, mupirocin should be used judiciously, as part of an integrated programme of infection control.

The efficacy of intranasal mupirocin in the prevention of staphylococcal infections: a review of recent experience

Staphylococcal infections remain an important cause of morbidity and mortality. Methicillin-resistant Staphylococcus aureus (MRSA) present a particular problem because of the costs of treatment and containing outbreaks. The role of nasal carriage of staphylococci in the epidemiology of staphylococcal infection has been recognized for over 30 years. Until recently, eradication of nasal carriage of S. aureus has proved difficult, with a variety of topical and systemic agents yielding poor results with either little discernible effect on nasal carriage or rapid recolonization. Mupirocin is a novel topical antibiotic with excellent antibacterial activity against staphylococci, including MRSA. Intranasal administration of calcium mupirocin has achieved excellent results in the eradication of nasal carriage of S. aureus and producing an associated reduction in S. aureus infection in a variety of clinical settings, including MRSA outbreaks, neonatal nurseries, haemodialysis, cardiothoracic surgery and familial staphylococcal infections. This article reviews the efficacy and safety of intranasal mupirocin in the prevention of staphylococcal infections.