Mesh-related Infection Research Articles

Surface modification of polypropylene mesh devices with cyclodextrin via cold plasma for hernia repair: Characterization and antibacterial properties

Light weight polypropylene (PP) mesh is the most widely used implant among all other synthetic meshes for hernia repair. However, infection is the complication associated to all synthetic meshes after hernia repair. Thus, to manage mesh related infection; antibacterial drug is generally loaded to surgical implants to supply drug locally in mesh implanted site. Nevertheless, PP mesh restricts the loading of antibacterial drug at operated area due to its low wettability. The aim of this study was to introduce a novel antimicrobial PP mesh modified with β-cyclodextrine (CD) and loaded with antimicrobial agent for infection prevention. A cold oxygen plasma treatment was able to activate the surfaces of polypropylene fibers, and then CD was incorporated onto the surfaces of PP fibers. Afterward, triclosan, as a model antibacterial agent, was loaded into CD cavity to provide desired antibacterial functions. The modified polypropylene mesh samples CD-Tric-1, CD-Tric-3 exhibited excellent inhibition zone and continuous antibacterial efficacy against E. coli and S. aureus up to 6 and 7 days respectively. Results of AFM, SEM, FTIR and antibacterial tests evidenced that oxygen plasma process is necessary to increase chemical connection between CD molecules and PP fibers. The samples were also characterized by using EDX, XRD, TGA, DSC and water contact angle.

Mesh penetrating the cecum and bladder following inguinal hernia surgery: a case report

BackgroundTension-free repair using mesh is a common inguinal hernia surgical procedure. However, various complications such as mesh-related infection and recurrence may develop as a result. Moreover, although rare, there are also reports of intestinal obstruction caused by adhesion of the mesh to the intestinal wall and cases of mesh migration into various organs. Here, we report our experience with a patient in whom mesh extraction was performed due to migration of mesh into the intestinal tract following inguinal hernia surgery and formation of a fistula with the bladder.Case presentationOur patient was a 63-year-old Japanese man who had a history of operative treatment for right inguinal hernia during early childhood. Because a relapse subsequently occurred, he was diagnosed as having recurrent right inguinal hernia at the age of 56 years for which operative treatment (the Kugel method) was performed. He presented to our hospital 6 years later with the chief complaint of lower abdominal pain. Computed tomography findings revealed a mass shadow in contact with his bladder and cecal walls, and enteric bacteria were detected in his urine. Furthermore, because lower gastrointestinal endoscopic findings confirmed mesh in the cecum, we performed operative treatment. The mesh had migrated into the cecum and a fistula with his bladder had formed. We removed the mesh through ileocecal resection and partial cystectomy.ConclusionsIt appeared that a peritoneal defect occurred when the mesh was placed, allowing the mesh to migrate into our patient’s intestinal tract. Because contact between the mesh and the cecum resulted in inflammation, a fistula formed in his bladder. It is important to completely close the peritoneum when placing the mesh.

Biodegradable rifampicin-releasing coating of surgical meshes for the prevention of bacterial infections.

Polypropylene mesh implants are routinely used to repair abdominal wall defects or incisional hernia. However, complications associated with mesh implantation, such as mesh-related infections, can cause serious problems and may require complete surgical removal. Hence, the aim of the present study was the development of a safe and efficient coating to reduce postoperative mesh infections. Biodegradable poly(lactide-co-glycolide acid) microspheres loaded with rifampicin as an antibacterial agent were prepared through single emulsion evaporation method. The particle size distribution (67.93±3.39 μm for rifampicin-loaded microspheres and 64.43±3.61 μm for unloaded microspheres) was measured by laser diffraction. Furthermore, the encapsulation efficiency of rifampicin (61.5%±2.58%) was detected via ultraviolet–visible (UV/Vis) spectroscopy. The drug release of rifampicin-loaded microspheres was detected by UV/Vis spectroscopy over a period of 60 days. After 60 days, 92.40%±3.54% of the encapsulated rifampicin has been continuously released. The viability of BJ fibroblasts after incubation with unloaded and rifampicin-loaded microspheres was investigated using an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, which showed no adverse effects on the cells. Furthermore, the antibacterial impact of rifampicin-loaded microspheres and mesh implants, coated with the antibacterial microspheres, was investigated using an agar diffusion model with Staphylococcus aureus. The coated mesh implants were also tested in an in vivo mouse model of staphylococcal infection and resulted in a 100% protection against mesh implant infections or biofilm formation shown by macroscopic imaging, scanning electron microscopy, and histological examinations. This effective antibacterial mesh coating combining the benefit of a controlled drug delivery system and a potent antibacterial agent possesses the ability to significantly reduce postoperative implant infections.

A Diagnostic Dilemma of a Discharging sinus over the Anterior Abdominal Wall

Chronic mesh infection is one of the most challenging clinical conditions in the abdominal wall surgery. Whether an infected mesh must be totally removed or not, the role of antibiotics, the right timing for a repair and guidelines on how to treat the abdominal wall must be discussed. Incidences of mesh-related infection after herniare pair of up to 8% have been reported. The rate of infection is influenced considerably by underlying co-morbidity, and seems to be increased in patients with diabetes, immunosuppression or obesity. A clinician should strongly consider the possibility of a mesh-related infection in any patient who presents with fever of unknown aetiology, symptoms and ⁄ or signs of inflammation of the abdominal wall in the area of the mesh, or other less common clinical manifestations of mesh infection, such as an enterocutaneous fistula or abdominal abscess in the area of the mesh. Imaging techniques, including ultrasound and ⁄ or computerised tomography, can be useful for the diagnosis of mesh infection. When a mesh-related infection occurs, a combined medical and surgical approach involving intravenous antimicrobial agents and complete surgical removal of the mesh is the preferred management strategy.

PWE-394 Are we misdiagnosing foreign body reaction to biologic implants as mesh-related infection?

Introduction Concern regarding mesh erosion has led to the increased use of biological implants in laparoscopic ventral rectopexy (LVR). There is a growing recognition that biological implants are not inert and their introduction into the body triggers a sequence of events leading to the formation of foreign body giant cells at the tissue/implant interface. This could lead to systemic inflammatory response syndrome (SIRS) that mimics mesh-related infection. Method The records of 4 patients readmitted after LVR were assessed retrospectively. A radiologist with an interest in pelvic floor surgery reviewed their CT scans. Results We performed 27 LVRs from October 2013–2014 using Biodesign®biological implant and 19 using synthetic mesh. 4 patients (15%) from the biologic cohort were re-admitted with pain and pyrexia and a pelvic abscess was suspected. CRP was raised in 4 (mean 276 at readmission and 99 at discharge) but in only one was the WCC elevated. All 4 received antibiotics and 2 patients had percutaneous drainage of sterile collections while the other two had no intervention. Those treated with drainage had a longer hospital stay and a delayed recovery compared with the observation only group. All made a complete recovery and none had either symptoms of their original prolapse or dysfunctional defecation. None of the patients in the synthetic mesh group were readmitted. Conclusion SIRS is a natural reaction to the implantation of non-inert foreign material as evidenced by elevated inflammatory mediators in the absence of a neutrophilia. This small study would suggest that the drainage of such 9collections9 following insertion of biological meshes is not only unnecessary but may run the risk of introducing sepsis into a sterile environment. The routine use of intravenous antibiotics might be unnecessary and a watchful waiting approach should be considered. Disclosure of interest None Declared.

Direct demonstration of bacterial biofilms on prosthetic mesh after ventral herniorrhaphy.

Prosthetic mesh is employed routinely in the treatment of ventral and parastomal hernias, but its use can lead to major complications, including infection, extrusion, and fistula. Bacterial biofilms have been posited to play a role in mesh-related infection, but although bacteria have been noted to form biofilms on mesh surfaces in vitro, they have never been visualized directly in biofilms on mesh recovered from patients experiencing infectious complications. Five patients who developed complications after ventral hernia repair with prosthetic mesh were operated on again. Explanted mesh was examined for biofilm with confocal laser scanning microscopy (CLSM) and fluorescence in situ hybridization (FISH). In two cases, a novel molecular assay (the Ibis T5000) was used to characterize the biofilm-forming bacteria. The CLSM examination demonstrated adherent biofilms on mesh surfaces in all five patients. Biofilms also were noted on investing fibrous tissue. The FISH study was able to discriminate between bacterial species in polymicrobial biofilms. In two patients the Ibis T5000 detected more species of constituent biofilm bacteria than did standard culture. Removal of the mesh and reconstruction with autologous tissues or biologic materials resolved the presenting complaints in all cases. Bacterial biofilms should be considered an important contributor to the pathology and complications associated with prosthetic mesh implanted in the abdominal wall. If biofilms are present, complete removal of the mesh and repair of the resulting defect without alloplastic materials is an effective intervention.

Prospective randomized, double-blind, placebo controlled trial to evaluate infection prevention in adult patients after tension-free inguinal hernia repair

Infection is one of possible complications after prosthetic material hernia repair surgery. Antibiotic prophylaxis is applied routinely in China, but its effect is still controversial. The present study aims to offer direct clinical evidence on prevention of infection after tension-free inguinal hernia repair. A total of 1,200 cases with primary inguinal hernia treated in 6 hospitals in Shaanxi Province were enrolled in this study. They were randomly divided into three groups (n = 400 per group): placebo control group, Cefazolin group and Levofloxacin group after tensionfree inguinal hernia repair using polypropylene mesh. Hernia type, age, gender, weight and complications were recorded. The surgical-site infection was diagnosed according to APIC, CDC criteria (http://www.apic. org). Infections were evaluated every other day in the first week, and then at 14 days, 21 days and 30 days following surgery. Two cases from the placebo group, 3 from the Cefazolin group and 3 from the Levofloxacin group failed to follow-up. Six patients (2 non-following the protocol, 2 severe depression, and 2 laparoscopic surgery) from the placebo group, 14 (8 nonreceiving trial medication, 5 laparoscopic surgery, and 1 failure to tolerance) from the Cefazolin group, and 12 (2 combination of antibiotic usage, 5 laparoscopic surgery and 5 failure to tolerance) from the Levofloxacin group were excluded. The data of the 1,160 cases were statistically analyzed in the incidence rates of surgical-site infection and complications after inguinal hernia repair. Surgical-site infection including wound infection, cellulitis or mesh-related infection was found in 20 cases (5.1%) of the control group, 15 (3.92%) of the Cefazolin group and 17 (4.42%) of the Levofloxacin group, and the difference among the three groups was not statistically significant (χ2 = 0.438, p = 0.803). There was also no significant difference in post-surgery complications including seroma (p = 0.6366), urinary retention (p = 0.8136), fat liquefaction (p = 0.8061), pulmonary infection (p = 0.1911), and urinary tract infection (p = 0.8144) among the three groups. Prophylactic use of Cefazolin or Levofloxacin did not significantly decrease the risk of wound infection in these patients undergoing inguinal hernia repair. The present results do not support the administration of antibiotic prophylaxis for tension-free inguinal hernia repair. *The authors contributed equally to this work.

Laparoscopic repair of vaginal vault prolapse by lateral suspension with mesh

To evaluate the long-term outcomes of laparoscopic lateral suspension using mesh reinforcement for symptomatic posthysterectomy vaginal vault prolapse. We analyzed in a prospective cohort study all the women treated by laparoscopic lateral suspension with mesh for symptomatic vaginal vault prolapse between January 2004 and September 2010. In this procedure, the mesh is laterally suspended to the abdominal wall, posterior to the anterior superior iliac spine. We performed systematic follow-up examinations at 4 weeks, 6 months and yearly postoperatively. Clinical evaluation of pelvic organ support was assessed by the pelvic organ prolapse quantification (POP-Q) grading system. Main outcome measures were recurrence rate, reoperation rate for symptomatic recurrence or de novo prolapse, mesh erosion rate, reoperation rate for mesh erosion, total reoperation rate. Of the 73 patients seen at a mean 17.5 months follow-up, recurrent vaginal vault prolapse was registered in only one woman (success rate of 98.6 %). When considering all vaginal sites, we observed a total of 13 patients with recurrent or de novo prolapse (17.8 %). The non-previously treated posterior compartment was involved in eight cases (new appearance rate of 11 %). Of these 13 women, only 6 were symptomatic, requiring surgical management (reoperation rate for genital prolapse of 8.2 %). Four patients presented with mesh erosion into the vagina (5.5 %). Two required partial vaginal excision of the mesh in the operating room (2.7 %). There were no mesh-related infections. The total reoperation rate was 11 %. Laparoscopic lateral suspension with mesh interposition is a safe and effective technique for the treatment of vaginal vault prolapse. This approach represents an alternative procedure to the laparoscopic sacrocolpopexy.

Short‐term results for laparoscopic ventral rectopexy using biological mesh for pelvic organ prolapse

There is growing evidence that laparoscopic ventral rectopexy (LVR) is an effective treatment for pelvic organ prolapse and obstructive defaecation caused by rectocele. LVR is usually performed using synthetic mesh despite concerns about mesh erosion. We present our experience of using a porcine dermal collagen mesh (Permacol™) for LVR, which is the largest such case series to date. Data on 65 patients were collected prospectively from May 2008 to October 2010. Outcome measures were complications, recurrence, length of hospital stay, patient satisfaction, Wexner constipation score and Wexner incontinence score. Preoperative and postoperative scores were compared using the two-tailed Wilcoxon signed rank test. P<0.05 was considered statistically significant. There were statistically significant improvements in the Wexner constipation scores at 6 months and 1 year (both P<0.0001) and in faecal incontinence scores at 6 months (P<0.0001) and 1year (P=0.0002). There were no cases of mesh erosion or mesh-related infection in our series. Recurrence of symptoms occurred in two patients (3.1%). Symptoms were rated as much better or better by 93% of patients at 6months and this was sustained at 1year (96%). In the short term, LVR using biological mesh is safe and as effective as synthetic mesh, with high patient satisfaction. Constipation and faecal incontinence scores were both improved.

Multilayer, degradable coating as a carrier for the sustained release of antibiotics: Preparation and antimicrobial efficacy in vitro

One of the most critical post-surgical complications is mesh-related infection. This paper describes how a commercially available polypropylene (PP) mesh was modified to minimize the risk of post-implantation infection. A dual drug-release coating was created around mesh filaments using an airbrush spray system. This coating was composed of three layers containing ofloxacin and rifampicin dispersed in a degradable polymer reservoir made up of [poly(ε-caprolactone) (PCL) and poly(dl-lactic acid) (PLA)]. Drug release kinetics were managed by varying the structure of the degradable polymer and the multilayer coating. In vitro, this new drug delivery polymer system was seen to be more rapidly invaded by fibroblasts than was the initial PP mesh. Active mesh showed excellent antibacterial properties with regard to microorganism adhesion, biofilm formation and the periprosthetic inhibition of bacterial growth. Sustained release of the two antibiotics from the coated mesh prevented mesh contamination for at least 72h. This triple-layer coating technology is potentially of great interest for it can be easily extrapolated to other medical devices and drug combinations for the prevention or treatment of other diseases.

Surgical placement of biologic mesh spacers prior to external beam radiation for retroperitoneal and pelvic tumors

PurposeTo determine the feasibility of surgical placement of biologic mesh spacers to displace bowel and other radiation-sensitive organs prior to external beam radiation for difficult retroperitoneal and pelvic tumors. Methods and MaterialsTumors were resected if possible, and intraoperative electron radiation therapy (IOERT) was directed to the tumor or tumor bed in selected patients. Biologic mesh spacers comprised of cadaveric human skin treated to remove cells and preserve extracellular matrix (Alloderm; Lifecell, Branchburg, NJ) were then placed around the tumor or tumor bed. External radiation techniques included proton beam radiation therapy (PBRT) and intensity modulated radiation therapy (IMRT). ResultsPatients had primary sarcomas (n = 2), radiation-associated sarcomas (n = 1), or isolated metastases (n = 2) in the retroperitoneum or pelvis. One patient received preoperative radiation. Three tumors were marginally resected (R1 resection) while 2 tumors were left in situ, and 3 patients received IOERT (10-17 Gy) to the tumor or tumor bed. Up to 4 sheets of biologic mesh were used as spacers around the tumor or tumor bed to displace small bowel, colon, ureter, bladder, or pancreas. The average distance of the 4 closest organs prior to mesh placement was 1.3-9 mm and after mesh placement was 8.0-23.5 mm. Preoperative or postoperative radiation 36-76 Gy was delivered by IMRT or PBRT. There were no early complications from mesh placement and late complications possibly related to radiation included 1 vertebral body compression fracture and 1 deep vein thrombosis. There were no mesh-related infections and none of the meshes required removal. All 5 patients currently remain free of disease progression after 3-38 months. ConclusionsBiologic mesh spacers can be placed around tumors or tumor beds to displace radiation-sensitive organs and may allow for safer delivery of external beam radiation.

Achromobacter xylosoxidans mesh related infection: A case of delayed diagnosis and management

We present the first case of mesh related infection caused by Achromobacter xylosoxidans after ventral hernia repair. After repair of a small paraumbilical hernia, the postoperative course was complicated by persistent discharging sinuses despite the removal of underlying polypropylene mesh. Removal of an intrabdominal omental inflammatory mass containing pus that showed growth of A. xylosoxidans led to the resolution of all the symptoms.

Risk Factors for Mesh‐related Infections After Hernia Repair Surgery: A Meta‐analysis of Cohort Studies

Mesh infection, although infrequent, is a devastating complication of mesh hernioplasties. The aim of this study was to systematically review and synthesize the available evidence on risk factors for synthetic mesh infection after hernioplasty. A systematic search was performed in PubMed and Scopus databases. The extracted data were synthesized with the methodology of meta-analysis. We identified six eligible studies that reported on 2,418 mesh hernioplasties. The crude mesh infection rate was 5%. Statistically significant risk factors were smoking (risk ratio [RR]=1.36 [95% confidence interval (CI): 1.07, 1.73]; 1,171 hernioplasties), American Society of Anesthesiologists (ASA) score ≥3 (RR=1.40 [1.15, 1.70]; 1,682 hernioplasties), and emergency operation (RR=2.46 [1.56, 3.91]; 1,561 hernioplasties). Also, mesh infections were significantly correlated with patient age (weighted mean difference [WMD]=2.63 [0.22, 5.04]; 2,364 hernioplasties), ASA score (WMD=0.23 [0.08, 0.38]; 1,682 hernioplasties), and the duration of the hernioplasty (WMD=44.92 [25.66, 64.18]; 833 hernioplasties). A trend toward higher mesh infection rates was observed in obese patients (RR=1.41 [0.94, 2.11]; 2,243 hernioplasties) and in patients operated on by a resident (in contrast to a consultant; RR=1.18 [0.99, 1.40]; 982 hernioplasties). Mesh infections usually resulted in mesh removal, and common pathogens included Staphylococcus spp., Enterococcus spp., and gram-negative bacteria. Patient age, ASA score, smoking, and the duration and emergency setting of the operation were found to be associated with the development of synthetic mesh infection. The heterogeneity of the available evidence should be taken under consideration. Prospective studies with a meticulous follow-up are warranted to further investigate mesh-related infections.

New antibiotic-eluting mesh used for soft tissue reinforcement

The surgical implantation of prostheses for soft tissue repair may be followed by post-operative mesh-related infection, a significant and dramatic complication, that is treated by mesh removal. A new antibiotic-eluting mesh has been manufactured on pre-existing polypropylene prostheses using an airbrush spraying technology. Among the degradable polymers tested as coating agents and drug reservoirs, poly(ε-caprolactone) (PCL), which is deposited after heating, provides a homogeneous, regular and smooth shell around the polypropylene filaments of the mesh without dramatically altering the biomechanical properties of the new modified mesh. An anti-infective drug (e.g. ofloxacin) is incorporated into this polymeric coating giving a limited burst effect followed by sustained drug diffusion for several days. An ofloxacin-eluting mesh has demonstrated excellent antibacterial activity in vitro on Escherichia coli adherence, biofilm formation and inhibitory diameter, even with low drug loads. Although further in vivo investigations are required to draw conclusions on the anti-infective effectiveness of the coated mesh, the airbrush coating of ofloxacin–PCL on existing prostheses is already potentially appealing in an effort to decrease post-operative infection.

Biological mesh for abdominal wall hernia synthetic mesh multidrug-resistant Pseudomonas aeruginosa infection: Report of a case

The use of biological mesh for the treatment of synthetic mesh-related infections in patients who undergo ventral hernia repair has been considered over the past few years. Removal of the infected synthetic mesh, which may be required in such cases, can result in recurring herniation. Biological implants have thus been recently used for the reconstruction of the existing defect. We herein present the case of a patient who developed multidrug-resistant Pseudomonas aeruginosa synthetic mesh infection following hernia repair, which was managed by the removal of the material and the application of a biological mesh in the contaminated area.

Mesh biocompatibility: effects of cellular inflammation and tissue remodelling

Mesh biocompatibility is basically determined by the foreign body reaction (FBR). In contrast to physiological wound healing and scar formation, the FBR at the host-tissue/biomaterial interface is present for the lifetime of the medical device. The cellular interactions at the mesh/tissue interface proceed over time ending up in a chronic inflammatory process. The time course of the FBR has been studied extensively and consists of three crucial steps that are protein absorption, cell recruitment and, finally, fibrotic encapsulation and extracellular matrix formation. Each of these steps involves a complex cascade of immune modulators including soluble mediators and various cell types. Recent research has focused on the cellular and molecular interactions of the distinct phases of the FBR offering a new basis for therapeutical strategies. The highly dynamic process of the FBR is considerably influenced by the biomaterial composition. Modifications of the type of polymer, the material weight, the filament structure and the pore size are realized and have substantial effects on the in vivo biocompatibility. Moreover, modern mesh technology aims to utilize the available implants as carrier systems for bioactive drugs. Studies in animal models account for the efficiency of these drugs that aim to reduce mesh-related infections or to minimize FBR by influencing inflammation or extracellular matrix remodelling. A thorough understanding of the molecular mechanisms of FBR provides a sophisticated background for the development of new biomaterials at least as carrier systems for bioactive reagents to reduce inflammation and to improve clinical outcome.

Mesh-related chronic infections in silicone-coated polyester suburethral slings

despite claims of equivalence to the tension-free vaginal tape, a variety of suburethral slings have been introduced, with various modifications. Complications in certain synthetic slings and meshes have led to a recent FDA public health notification. we report the case histories and management of five women with complications following implant of an InFast sling. four of the five patients presented with symptom of chronic vaginal discharge, one presenting with irritative voiding symptoms and bladder pain. Resolution of presenting symptoms requires total removal of this silicone-coated polyester mesh, which often requires a combined vaginal-abdominal approach. the silicone-coated mesh of the AMS InFAST sling, can become a focus for chronic infection forming a sinus tract into the vagina or other viscus, causing symptoms years after its placement.

Can infected composite mesh be salvaged?

Composite mesh, once infected, creates a difficult dilemma. Many times, the mesh is deemed unsalvageable and leads to removal and potentially more morbidity. This article describes successful salvage of infected composite mesh. Retrospective chart review of composite mesh placed at a single community hospital from January 2002 to November 2007. A total of 356 composite mesh implants were placed: 218 Ventralex and 138 Composix Kugel. All had open repairs; 153 were men and 203 were women with a mean age of 45.3 years (range 21-90), and a mean body mass index of 33.3 (range 20-60). Eleven patients developed mesh-related infections, presenting an average of 42 days postoperatively (range 10 days to greater than 4 years post repair). All were treated initially with conservative measures. Four patients ultimately required mesh removal (all had Composix Kugel repairs). Seven patients, however, (one Ventralex and six Composix Kugel) were successfully salvaged with conservative office-based methods, including dressing changes, local wound debridement, partial mesh excision, wound vacuum, and antibiotics. None of the salvaged infected composite mesh patients developed hernia recurrences after at least 3 years. As long as there is no evidence of extensive mesh infection or overt sepsis, infected composite mesh can be salvaged. Treatment of these often complex patients must be individualized.

Antibiotic-Releasing Mesh Coating to Reduce Prosthetic Sepsis: An In Vivo Study

Mesh related infections are a major challenge with few adequate prevention and treatment options. We evaluate the ability of a slow affinity based drug-releasing polymer to prevent a Staphylococcus aureus mesh infection using an in vivo animal model. A surgical wound infection model was used to evaluate a vancomycin (VM) drug loaded polymer. Fifty animals underwent creation of a dorsal subcutaneous pocket, insertion of a standard piece of polyester mesh and an inoculum of a clinical strain of green fluorescent protein (GFP) labeled S. aureus (SA) (10(4) CFU/mL). Animals were then randomly allocated to different treatment groups [saline flush (n = 10), VM flush (n=20), VM polymer coated mesh (n = 20)]. Local tissue and mesh were evaluated at 2 (n = 25) and 4 wk (n = 25) via standard culture studies. Median GFP SA growth from tissue-mesh homogenates were as follows: 2 wk: saline flush = 2.2 × 10(7) CFU/g; VM flush = 1.6 × 10(6) CFU/g; VM polymer = sterile cultures [P value 0.0001]; 4 wk: saline flush = 1.5 × 10(6) CFU/g; VM flush = 1.6 × 10(3) CFU/g; VM polymer = sterile cultures [P value 0.001]. Mesh infections pose a significant challenge in hernia surgery with suboptimal treatment modalities and little innovation. Using an in vivo wound infection model our novel affinity based drug delivering polymer was able to effectively prevent a SA mesh infection with efficacy demonstrated at 2 and 4 wk.

Vacuum Assisted Closure® therapy in the treatment of mesh infection after hernia repair

Mesh related infection after prosthetic abdominal wall hernia repair is a difficult clinical problem, particularly in an era of evolving microbial resistance. Commonly advocated treatment for such infection involves complete mesh excision which usually leaves a complicated weak wound. We report the use ofVAC therapy for mesh infections that allows mesh preservation leaving a sound wound. From june 2002 to January 2007, four patients with mesh related infection after abdominal wall hernia repair were treated with VAC therapy. Patients' notes were reviewed to gather clinical details. Mesh infection was evident after a variable period (day three to eight years) following hernia repair. Of the four patients, one had infection with methicillin resistant Staphylococcus aureus (MRSA), while the bacteriological cultures from two confirmed Staphylococcus aureus in one and a mixture of Pseudomonas and enterococcus species in the other. One patient failed to show significant bacterial growth on pus swab culture, having had prior broad-spectrum antibiotic treatment for mesh infection. Three patients had complete mesh preservation and one had partial mesh excision. All patients were treated with VAC therapy, following the drainage of their operation sites, until the visible mesh was covered with granulation (one to seven weeks). No patient had a recurrent hernia after complete wound healing. VAC therapy allows salvage of infected exposed mesh by promoting granulation through the mesh. Judicious use of VAC therapy may prevent the need of mesh excision and its wound related complications.