Microbiologic Profile of Nipple Swab Culture and its Association With Postoperative Complications in Prosthetic Breast Reconstruction.

BACKGROUND: In breast surgeries, a lactiferous duct leading to lactic glands of breast parenchyma allows direct contamination by normal bacterial flora of the nipple-areola complex. Complete blockage of nipple flora from the intraoperative field is almost impossible. OBJECTIVES: We aimed to analyze the microbiological profile of nipple flora of breast cancer patients who underwent an implant-based immediate breast reconstruction after a total mastectomy, and to evaluate the association of nipple bacterial flora with postoperative complications. METHODS: A retrospective chart review was performed of patients who underwent an implant-based immediate breast reconstruction after a total mastectomy. A nipple swab culture was performed preoperatively. Patient demographics, surgical characteristics, and complications were compared between positive and negative nipple swab culture groups. Microbiological profile data including antibacterial resistance were collected. RESULTS: Among 128 breasts, 60 cases (46.9%) had positive preoperative nipple swab culture results. Staphylococcus epidermidis accounted for 41.4% of microorganisms isolated. A multivariate logistic regression analysis of postoperative complications revealed that the presence of nipple bacterial flora was a risk factor for capsular contracture. Seven cases of postoperative infection were analyzed. In 2 cases (40% of pathogen-proven infection), the causative pathogen matched the patient's nipple bacterial flora, which was methicillin-resistant S. epidermidis in both cases. CONCLUSIONS: Nipple bacterial flora was associated with an increased risk of capsular contracture. Preoperative analysis of nipple bacterial flora can be an informative source for treating clinically diagnosed postoperative infections. More studies are needed to determine the effectiveness of active antibiotic decolonization of the nipple.

Repeated Lipoteichoic Acid Injection at Low Concentration Induces Capsular Contracture by Activating Adaptive Immune Response through the IL-6/STAT3 Signaling Pathway.

BACKGROUND: Capsular contracture is the most common complication of breast implantation surgery. Bacterial contamination was considered to play an important role in the occurrence of capsular contracture, and Gram-positive bacteria such as Staphylococcus epidermidis were discovered in the clinical specimens. Lipoteichoic acid (LTA) was a component of the cell wall of Gram-positive bacteria and was sufficient in the pathogenicity of the bacteria. The authors assumed that LTA could trigger the immunologic response against the implant and cause capsular contracture. METHODS: The authors developed a rat model of capsular contracture by repeated injection of 10 µg/mL LTA. The histologic changes of the capsule tissue were measured by hematoxylin and eosin, sirius red, Masson, and immunohistochemical staining. The expression of related cytokines was measured by quantitative real-time polymerase chain reaction. The downstream pathway activation was shown by Western blot. The authors also applied tocilizumab, an interleukin (IL)-6 receptor antagonist, to verify the role of IL-6 in this pathologic process. RESULTS: The authors discovered that repeated LTA injection, at a low concentration, could induce the thickening of capsule tissue, the deposition of collagen fiber, and the activation of myofibroblasts. The IL-6/signal transducer and activator of transcription 3 signaling pathway was activated in this process, and the inhibition of IL-6 receptor could relieve the symptoms. B cells and T-helper cells, especially T-helper type 1, could be related to this phenomenon. CONCLUSIONS: The authors' research corroborated that subclinical infection could trigger capsular contracture, and the immune system played an important role in this process. The authors' results provided a possible research direction for the mechanism of bacterial infection-induced immune response against breast implants. CLINICAL RELEVANCE STATEMENT: The authors' research provides a possible research direction for the mechanism of bacterial infection-induced immune response against breast implants, and a potential target for predicting the prognosis of capsular contracture.

Exhaustive diagnosis of breast implants with capsular contracture: The microbiology laboratory as a major support.

The most frequent complications of post-mastectomy reconstructions are breast implant (BI) infection and capsular contracture (CC). The diagnosis of BI colonization is based on cultures from the sonicated BI and from the capsule tissue. Therefore, we first aimed to assess the yield of conventional culture and molecular techniques in periprosthetic fluid, in addition to BI and capsular tissue. Moreover, we compare colonization and biofilm production between patients with and without CC. During 19 months, we prospectively included patients whose BIs had been removed and divided them into two groups: A (CC, Baker III-IV) and B (no CC). Samples were obtained for conventional culture, 16 s rRNA PCR, and MALDI-TOF. Biofilm production was also evaluated. We included 81 BIs from 69 patients with CC (22) and without CC (53). Forty-three (53.1%) of the 81 BIs had ≥1 positive culture. The culture was positive in 57.1% and 50.9% in groups A and B, respectively (p = 0.645). The highest 16 s rRNA PCR positivity rate was detected in capsular tissue (40.5%). MALDI-TOF was unable to detect colonization in any of the samples. High biofilm production was the following: high biomass: A, 29.8%; B, 39.7% (p = 0.293); high metabolic activity: A, 36.2%; B, 34.5% (p = 0.857). We confirm that cultures from different sites are mandatory to ensure a proper diagnosis of BI colonization. Our study is the first to demonstrate that CC was not associated with BI colonization or high biofilm production. The application of molecular techniques in BI samples was not substantially useful for predicting colonization.

Microbial community compositions in breast implant biofilms associated with contracted capsules.

Subclinical bacterial infections (biofilms) are strongly implicated in breast augmentation failure due to capsular contracture, and while these infections are generally ascribed to common skin commensals, this remains largely unsubstantiated through robust cultivation independent analyses. To determine capsule biofilm microbial community compositions, we employed amplicon sequencing of the 16S rRNA gene using DNA extracted from breast implant capsule samples. These cultivation independent analyses revealed that capsule associated biofilms are more diverse than canonical single-species infections, but have relatively low diversity (~ <100 species) compared to many host-associated microbial communities. In addition to taxa commonly associated with capsular contracture, the biofilms analyzed comprised a number of taxa that escaped detection in cultivation-dependent work. We have also isolated several key taxa identified through the culture-independent analyses. Together our analyses reveal that capsule biofilms are more diverse than cultivation studies suggest and can be heterogeneous within an individual capsule, between breasts of the same patient, across similar implant types, and over a range in severity of contracture. The complex nature of these communities requires further study across a broader suite of patients in addition to higher resolution analyses including metagenomics to better assess the fundamental role of microorganisms in capsular contracture.

Capsular contracture around silicone miniimplants following bacterial contamination: an in vivo comparative experimental study between textured and polyurethane implants.

BACKGROUND: Capsular contracture remains a problem following breast implant surgery. Although impact of biofilm and implant surface on capsule formation has been demonstrated, interaction of microorganisms with different surface types has not been clarified yet. We aimed to compare the ability of biofilm formation of implants with different surfaces, under standard conditions and to demonstrate its impact on capsular contracture. METHODS: Twenty-four rats were divided into four groups. Mini-implants with three different surfaces (fine-textured, rough-textured and polyurethane) were placed on the dorsum of each rat. In Group-1, sterile implants were placed in submuscular pockets. In Group-2, implants were incubated in Staphylococcus epidermidis medium before implantation. In Group-3, before implantation, implants were immersed in Rifamycin solution following bacterial contamination. In Group-4, sterile implants were immersed in Rifamycin solution before implantation, and served as the control group. Rats were sacrificed at three months. Clinical, microbiological, histological and immunohistochemical evaluations were performed. RESULTS: Capsule contracture developed only on infected rough-textured implants. Rough-textured and polyurethane implants showed more biofilm formation than fine-textured implants. Capsule thickness and inflammatory cell density were higher on rough-textured implants compared to fine-textured implants (p = 0.004). Actin sequence was parallel and concentric on fine-textured and rough-textured implants; but was in irregular array on polyurethane implants. CONCLUSION: In presence of bacterial contamination, rough-textured implants have the most propensity of developing capsular contracture comparing to fine-textured and polyurethane implants at three months after implantation. Despite high bacterial load and biofilm formation, polyurethane implants are resistant to capsule contracture due to surface characteristics.

PCR Characterization of Microbiota on Contracted and Non-Contracted Breast Capsules.

BACKGROUND: The aetiology of capsular contracture around breast implants remains unclear. The leading theory is that a subclinical infection around the implant plays a role in the development of capsular contractions. Several studies found associations between the presence of bacteria and the occurrence of capsular contraction. However, it is unclear whether detected bacteria originate from the breast capsule, breast glandular tissue or skin contamination. Moreover, this has never been investigated with molecular techniques. The aim of this study was to assess the bacterial microbiota on breast capsules, glandular tissue and skin using a highly sensitive PCR assay. MATERIALS AND METHODS: Fifty breast capsules were collected during implant removal or replacement. Ten specimens of glandular breast tissue and breast skin were collected in females who were undergoing reduction mammoplasty. A sample specimen (4 mm) was sterilely obtained from all tissues. All specimens were analysed by IS-pro, a 16S-23S interspace region-based PCR assay. RESULTS: Low numbers of Staphylococcus spp. (four species in four capsules) were found on breast capsules. There was no difference in bacterial presence between normal and contracted capsules. The skin of the breast-harboured Streptococcus spp. and Staphylococcus spp. while the glandular tissue was sterile. CONCLUSION: The low numbers of bacteria found on the capsules are most likely caused by contamination during capsule removal. More and larger studies are needed to investigate the bacterial presence on breast capsules using a PCR assay. This is the first study in which breast capsules have been studied using a highly sensitive PCR assay. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Back to Basics: Could the Preoperative Skin Antiseptic Agent Help Prevent Biofilm-Related Capsular Contracture?

BACKGROUND: Capsular contracture (CC) has remained an unresolved issue throughout history. Strong evidence focuses on bacterial biofilm as its main source. A literature review revealed that more than 90% of bacteria found in capsules and implants removed from patients with Baker grade III-IV CC belong to the resident skin microbiome (Staphylococcus epidermidis, predominant microorganism). The use of an adequate preoperative skin antiseptic may be a critical step to minimize implant contamination and help prevent biofilm-related CC. OBJECTIVES: The authors sought to compare the effect of 2 different antiseptic skin preparations: povidone-iodine (PVP-I) vs chlorhexidine gluconate (CHG) on CC proportions after primary breast augmentation through a periareolar approach. METHODS: In June of 2014, The Society for Healthcare Epidemiology of America proposed to use CHG for preoperative skin preparation in the absence of alcohol-containing antiseptic agents as strategy to prevent surgical site infection. The clinical safety committee of a surgical center in Colombia decided to change PVP-I to CHG for surgical site preparation thereafter. The medical records of 63 patients who underwent to primary breast augmentation through a periareolar approach during 2014 were reviewed. In the first 6 months PVP-I was used in 32 patients, and later CHG was employed in 31 patients. RESULTS: Pearson's chi-squared test to compare CC proportions between subgroups showed a statistically significant difference. The CC proportion was higher for patients who had antisepsis with PVP-I. CC was absent when CHG was employed. CONCLUSIONS: CHG as preoperative skin antiseptic for primary breast augmentation surgery was more effective than PVP-I to help prevent biofilm-related CC.

Plasma Activation of a Breast Implant Shell in Conjunction With Antibacterial Irrigants Enhances Antibacterial Activity.

BACKGROUND: Infection and capsular contracture are two of the most significant complications of breast-implant surgery. Both complications are associated with bacterial contamination of the implant surface. Plasma activation of the surface of a silicone breast implant changes its surface properties from water repelling (hydrophobic) to water absorbing (hydrophilic), thus making it possible for antibacterial irrigants to temporarily adsorb onto the implant surface. OBJECTIVES: To support our hypothesis that by changing the surface properties we could render antibacterial irrigation more effective in inhibiting bacterial growth on a breast implant shell. METHODS: An in vitro study using silicone discs cut from a textured silicone breast implant shell was performed by treating some of the discs with plasma activation and then exposing the discs to contamination with either Staphylococcus aureus or Pseudomonas aeruginosa and then variously treating the discs with 10% povidone iodine, Cefazolin, or Gentamicin. Bacterial contamination was verified and counted using contact plates as well as culture media. RESULTS: Plasma activation changed the wetting properties of the disc's surface from hydrophobic to hydrophilic. Nonplasma activated contaminated discs demonstrated clear bacterial growth both in the untreated group and in the antibacterial-treated group. Combining antibacterial treatment with plasma activation resulted in complete inhibition of bacterial growth in each of the groups treated with antibacterial irrigants. CONCLUSIONS: Combining plasma activation with topical antibacterial irrigants can inhibit the growth of bacteria on implant shell discs. By changing the properties of the surface from hydrophobic to hydrophilic, the adsorption of the antibacterial irrigants is enhanced.

The aetiopathogenesis of capsular contracture: A systematic review of the literature.

BACKGROUND: Capsular contracture is the most frequent complication after breast augmentation or reconstruction with breast implants. The immune system plays a prominent role in capsular contracture formation, albeit to an unknown extent. Bacterial contamination in situ has been hypothesized to be causative for capsular contracture. How this relates to the immunological processes involved is unknown. This article aims to provide an overview of immunological and bacterial factors involved in development of capsular contracture. MATERIALS AND METHODS: We undertook a systematic literature review focused on immunological factors and microbiota in relation to capsular contraction around implants. This systematic review was performed in accordance with the PRISMA guidelines. PubMed, EMBASE, and the Cochrane databases were searched from inception up to October 2016. Included studies were assessed for the following variables: subject characteristics, number of capsules, primary indication for surgery, surgical procedure, follow-up or implant duration, study methods, type of antibiotics or medical therapies and outcomes related to microbiota and immunological factors. RESULTS: Data on immunological factors and bacterial contamination were retrieved from 64 included studies. Notably the presence of macrophages and Staphylococcus epidermidis within capsules was often associated with capsular contracture. CONCLUSION: This review provides a clear overview of the immunological factors associated with capsular contracture and provides a hypothetical immunological model for development of the disease. Furthermore, an overview of bacterial contamination and associations with capsular contracture has been provided. Follow-up research may result in clinical recommendations to prevent capsular contracture.

Microbial Evaluation in Capsular Contracture of Breast Implants.

BACKGROUND: Capsular contracture around breast implants is a severe and unpredictable complication experienced by up to 50 percent of patients after breast augmentation and reconstruction, and represents a major cause leading to reoperation. Several lines of evidence point to the involvement of subclinical infections and of bacterial biofilm formation. METHODS: To reduce the incidence of capsular contracture following mammaplasty, the authors studied the correlation between contamination by exogenous and endogenous bacterial flora and the capacity to develop bacterial biofilm in mammary implants. The authors performed a microbiological study assessing microbial growth of swabs from breast skin, nipple-areola complex, and mammary gland biopsy specimens. Furthermore, the authors compared the results with the data resulting from cultural experiments from biopsy specimens of periprosthetic capsule, contracted or not, and from the surfaces of the relative prosthesis. RESULTS: Between July of 2012 and July of 2013, a series of 65 female patients from the area of Naples, Italy, and its province, who underwent breast plastic surgery with the use of implants for aesthetic or reconstructive reasons, were included in the study. The authors noticed that there is a greater tendency for capsular contracture to form in oncologic patients who received radiotherapy, patients with precedent capsular contracture, and patients with cutaneous contamination by biofilm-producing microbes. CONCLUSIONS: Although all of the new technical procedures tend to reduce the amount of bacterial charge that comes into contact with the prosthesis at the time of its introduction, a minimal amount must always be taken for granted. This is the rationale for a preventative personalized antibiotic therapy. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.