Microbiology of chronic mesh infection.

PURPOSE: Mesh infection following hernia repair is one of the most dreaded complications of hernia surgery. Mesh sinus, infected seromas, mesh extrusion, and mesh-related enteric fistulas are common complications associated with synthetic mesh. This study aimed to review the microbiota of mesh infection in 100 patients submitted to mesh explantation. METHODS: We reviewed the charts of patients presenting with a history of mesh infection lasting or arising six months or more after mesh placement. All patients who submitted to abdominal wall repair with complete removal of an infected mesh and presenting a positive culture were included. The microbiology analysis was based on positive cultures obtained from the fluids and tissues surrounding the mesh or positive cultures of the mesh. Microorganisms were divided into gram-positive or gram-negative, aerobic or anaerobic, and fungi. RESULTS: Pure aerobic gram-positive cultures were encountered in 50% of the patients, followed by a combination of aerobic gram-positive/gram-negative (8%) and pure gram-negative cultures (6%). Anaerobes were recovered from 31% of patients. Fungi were recovered from 6%. Staphylococcus aureus was identified in 64% of cultures, with methicillin-resistant Staphylococcus aureus present in 42% and methicillin-sensitive Staphylococcus aureus in 22%. Among aerobic gram-negative infections, six (17%) were caused by multi-resistant bacteria, including Pseudomonas aeruginosa, Proteus mirabilis, Acinetobacter baumanii, Klebsiella pneumoniae complex, and Enterobacter cloacae complex. CONCLUSION: Staphylococcus aureus plays a significant role in the pathogenesis of synthetic mesh infection. Staphylococcus aureus, isolated in 64% of cultures, accounted for most single bacterial infections and was the prevalent germ in mesh sinus and infected seromas. Gram-negative infection occurred in 35%. Anaerobes occurred in 31%, commonly encountered in polymicrobial infections. Most fungi cultures happened in patients with enteric fistulas.

Could polypropylene mesh impair male reproductive organs? Experimental study with different methods of implantation.

PURPOSE: To evaluate the vas deferens and testicles of rats submitted to bilateral inguinotomy and polypropylene (PP) mesh placement. METHOD: Sixty Wistar rats were randomized into three groups: Control (inguinotomy only), mesh placement over the vas deferens (Mesh-DD) or under the spermatic funiculus (Mesh-SF). The following analyses were performed: vas deferens morphometry (lumen area and wall thickness), quantification of collagen fibers, spermatogenesis, apoptosis (cleaved caspase-3 and TUNEL) and cellular proliferation (Ki67). Quantitative gene expression (qPCR) for apoptosis and inflammatory cytokines were evaluated by RT-PCR. RESULTS: In the apoptosis pathway, Mesh-DD showed one upregulated gene (Il10) and three downregulated genes (Fadd, Tnfrsf1b and Xiap). In Mesh-SF, 17 genes were downregulated. In the inflammation pathway (Mesh-DD), one gene was upregulated (Il1r1), and one gene was downregulated (Ccl12). In Mesh-SF, three genes were upregulated (Il1r1, Tnfsf13b and Csf1), and two were downregulated (Ccl12 and Csf2). PP mesh placement preserved spermatogenesis and did not alter the vas deferens or the testicle. In the ductus deferens, there was reduced luminal area (30 days), increased wall thickness (90 days), and increased type III collagen and cell proliferation (30 and 90 days) (p < 0.05). In the testicle, cell proliferation was greater in the Mesh-DD (p < 0.05). CONCLUSIONS: PP mesh, whether or not in direct contact with spermatic funicular structures, induces changes that were not sufficient to cause damage to the evaluated organs.

The use of synthetic mesh in contaminated and infected abdominal wall repairs: challenging the dogma-A long-term prospective clinical trial.

BACKGROUND: Abdominal wall reconstruction in patients presenting with enteric fistulas and mesh infection is challenging. There is a consensus that synthetic mesh must be avoided in infected operations, and the alternatives to using synthetic mesh, such as component separation techniques and biologic mesh, present disappointing results with expressive wound infection and hernia recurrence rates. METHODS: A prospective clinical trial designed to evaluate the short- and long-term outcomes of 40 patients submitted to elective abdominal wall repair with synthetic mesh in the dirty-infected setting, and compared to a cohort of 40 patients submitted to clean ventral hernia repairs. Patients in both groups were submitted to a single-staged repair using onlay polypropylene mesh reinforcement. RESULTS: Groups' characteristics were similar. There were 13 (32.5%) surgical site occurrences in the infected mesh (IM) group, compared to 11 (27.5%) in the clean-control (CC) group, p = 0.626. The 30-day surgical site infection rate was 15% for the IM group vs. 10% for the CC cases, p = 0.499. One patient required a complete mesh removal in each group. The mean overall follow-up was 50.2 ± 14.8 months, with 36 patients in the IM group and 38 clean-controls completing a follow-up of 36 months. There was one hernia recurrence (4.2%) in the IM group and no recurrences in the CC group. CONCLUSION: We demonstrated that using polypropylene mesh in the infected setting presented similar outcomes to clean repairs. The use of synthetic mesh in the onlay position resulted in a safe and durable abdominal wall reconstruction. TRIAL REGISTRATION: Study registered at Plataforma Brasil (plataformabrasil.saude.gov.br), CAAE 30836614.7.0000.0068. Study registered at Clinical Trials (clinicaltrials.gov), Identifier NCT03702153.

Sporadic Abdominal Wall Desmoid type Fibromatosis: treatment paradigm after thirty two years.

BACKGROUND: Desmoid-type fibromatosis is a benign mesenchymal neoplastic process. It exhibits an uncertain growth pattern and high recurrence rate. Previously radical surgical resection was the mainstay of treatment, but recently more surgeons are opting for conservative management with observation ("wait and see" policy). The authors intend to evaluate different therapeutic modalities and oncological outcomes for abdominal wall desmoid tumors. METHODS: We performed a retrospective study of patients who underwent surgical, hormonal or chemotherapy treatment for abdominal wall desmoid tumors between 1982 to 2014 at two institutions affiliated with the University of São Paulo, Brazil. RESULTS: In the study period, 32 patients were included. Twenty-seven patients had surgery upfront. Of those, 89% were women with a median age of 33 years. Mean tumor size was 10 cm. Pathology confirmed free margins in 92% of resections. Tumor recurrence rate was 11%, with median relapse-free survival being 24 months. Multivariate analysis showed that positive final margins (p < 0.001) and positive frozen section (p = 0.001) were independent predictors of recurrence. For the 5 patients who underwent pharmacological therapy, median age was 33 years and median tumor diameter before treatment was 13 cm. Four patients exhibited partial response by Response Evaluation Criteria in Solid Tumors (RECIST). The single patient who did not respond to RECIST underwent radiotherapy. CONCLUSION: Desmoid tumor treatment has been evolving over the past decade towards a more conservative approach. Pharmacological treatment may result in tumor size regression. When surgical excision is indicated, positive margins represent an important prognostic factor for local tumor recurrence.

Abdominal wall reconstruction after desmoid type fibromatosis radical resection: Case series from a single institution and review of the literature.

BACKGROUND: Abdominal wall desmoid type fibromatosis management has been changing over recent years, from an aggressive approach towards a more conservative one. When radical resection is indicated, the surgical team faces the challenge of abdominal wall reconstruction, for which optimal technique is still debated. The present study reports the experience from a single center with abdominal closures after desmoid type fibromatosis resection. MATERIAL AND METHODS: Retrospective analysis of patients who underwent abdominal wall closure after sporadic abdominal desmoid type fibromatosis radical resection from 1982 to 2013. RESULTS: Twenty-seven patients were included, mean tumor diameter was 10 + 5.3 cm, and the main choice of abdominal wall reconstruction was midline closure with anterior rectus sheath relaxing incisions and polypropylene onlay mesh (74% of the cases). Only 7% of the cases required more complex procedures for skin closure. Mean follow-up was 5 years and 89% remained disease-free. No grade 4 or 5 complications were observed. CONCLUSION: High midline fascial closure rate can be achieved after resection of abdominal wall desmoid tumor using relaxing incisions and mesh, with low complication rate.

A retrospective review and observations over a 16-year clinical experience on the surgical treatment of chronic mesh infection. What about replacing a synthetic mesh on the infected surgical field?

PURPOSE: To review the short- and long-term results in patients who underwent removal of infected or exposed mesh and reconstruction of the abdominal wall with simultaneous mesh replacement. METHODS: Patients undergoing removal of an infected or exposed mesh and single-staged reconstruction of the abdominal wall with synthetic mesh replacement over a 16-year period were retrospectively reviewed from a prospectively maintained database. Patients were operated and followed by a single surgeon. Outcome measures included wound complications and hernia recurrence. RESULTS: From 1996 until 2012, 41 patients (23 F, 18 M), with a mean age of 53.4 years and mean BMI of 31.2 ± 8 kg/m(2), were treated for chronic mesh infection (CMI). A suppurative infection was present in 27 patients, and 14 had an exposed mesh. The need for recurrent incisional hernia repair was observed in 25 patients; bowel resections or other potentially contaminated procedures were associated in 15 patients. The short-term results showed an uneventful post-operative course after mesh replacement in 27 patients; 6 (14.6%) patients developed a minor wound infection and were treated with dressings and antibiotics; 5 (12%) patients had wound infections requiring debridement and one required complete mesh removal. On the long-term follow-up, there were three hernia recurrences, one of which demanded a reoperation for enterocutaneous fistula; 95% of the patients submitted to mesh replacement were considered cured of CMI after a mean follow-up of 74 months. CONCLUSIONS: CMI can be treated by removal of infected mesh; simultaneous mesh replacement prevents hernia recurrence and has an acceptable incidence of post-operative acute infection. Standard polypropylene mesh is a suitable material to be used in the infected surgical field as an onlay graft.

Mesh cancer: long-term mesh infection leading to squamous-cell carcinoma of the abdominal wall.

PURPOSE: It is recognized that chronic inflammation can cause cancer. Even though most of the available synthetic meshes are considered non-carcinogenic, the inflammatory response to an infected mesh plays a constant aggression to the skin. Chronic mesh infection is frequently the result of misuse of mesh, and due to the challenging nature of this condition, patients usually suffer for years until the infected mesh is removed by surgical excision. METHODS: We report two cases of squamous-cell carcinoma (SCC) of the abdominal wall, arising in patients with long-term mesh infection. RESULTS: In both patients, the degeneration of mesh infection into SCC was presumably caused by the long-term inflammation secondary to infection. Patients presented with advanced SCC behaving just like the Marjolin's ulcers of burns. Radical surgical excision was the treatment of choice. The involvement of the bowel played an additional challenge in case 1, but it was possible to resect the tumor and the involved bowel and reconstruct the abdominal wall using polypropylene mesh as onlay reinforcement, in a single stage operation. He is now under adjuvant chemotherapy. The big gap in the midline after tumor resection in case 2 required mesh bridging to close the defect. The poor prognosis of case 2 who died months after the operation, and the involvement of the armpit, groin and mesenteric nodes in case 1 shows how aggressive this disease can be. CONCLUSION: Infected mesh must be treated early, by complete excision of the mesh. Long-standing mesh infection can degenerate into aggressive squamous-cell carcinoma of the skin.

A computerized tomography scan method for calculating the hernia sac and abdominal cavity volume in complex large incisional hernia with loss of domain.

Preoperative progressive pneumoperitoneum (PPP) is a safe and effective procedure in the treatment of large incisional hernia (size > 10 cm in width or length) with loss of domain (LIHLD). There is no consensus in the literature on the amount of gas that must be insufflated in a PPP program or even how long it should be maintained. We describe a technique for calculating the hernia sac volume (HSV) and abdominal cavity volume (ACV) based on abdominal computerized tomography (ACT) scanning that eliminates the need for subjective criteria for inclusion in a PPP program and shows the amount of gas that must be insufflated into the abdominal cavity in the PPP program. Our technique is indicated for all patients with large or recurrent incisional hernias evaluated by a senior surgeon with suspected LIHLD. We reviewed our experience from 2001 to 2008 of 23 consecutive hernia surgical procedures of LIHLD undergoing preoperative evaluation with CT scanning and PPP. An ACT was required in all patients with suspected LIHLD in order to determine HSV and ACV. The PPP was performed only if the volume ratio HSV/ACV (VR = HSV/ACV) was >or=25% (VR >or= 25%). We have performed this procedure on 23 patients, with a mean age of 55.6 years (range 31-83). There were 16 women and 7 men with an average age of 55.6 years (range 31-83), and a mean BMI of 38.5 kg/m(2) (range 23-55.2). Almost all patients (21 of 23 patients-91.30%) were overweight; 43.5% (10 patients) were severely obese (obese class III). The mean calculated volumes for ACV and HSV were 9,410 ml (range 6,060-19,230 ml) and 4,500 ml (range 1,850-6,600 ml), respectively. The PPP is performed by permanent catheter placed in a minor surgical procedure. The total amount of CO(2) insufflated ranged from 2,000 to 7,000 ml (mean 4,000 ml). Patients required a mean of 10 PPP sessions (range 4-18) to achieve the desired volume of gas (that is the same volume that was calculated for the hernia sac). Since PPP sessions were performed once a day, 4-18 days were needed for preoperative preparation with PPP. The mean VR was 36% (ranged from 26 to 73%). We conclude that ACT provides objective data for volume calculation of both hernia sac and abdominal cavity and also for estimation of the volume of gas that should be insufflated into the abdominal cavity in PPP.

Prosthetic repair of incisional hernia in kidney transplant patients. A technique with onlay polypropylene mesh.

The employment of synthetic mesh for incisional hernia repair in kidney-transplanted patients is rarely reported in the present literature. Many authors believe that mesh employment in such conditions is not safe due to fear of mesh related complications. From 1965 through 1999, a total of 1685 kidney transplants were performed at our Kidney Transplant Unit and 19 patients developed eventrations in the kidney transplant incision, an incidence of 1.1%. From September 1996 eight of these patients had prosthetic repair of the abdominal wall with onlay polypropylene mesh. All patients were under immunosuppressive therapy with prednisone, ciclosporine and azathioprine. Mean age was 48.8 years, mean body mass index was 22.5 and mean number of previous abdominal operations was 2.5. A large polypropylene mesh (Marlex mesh) was fixed over the aponeurosis after primary closure of the aponeurotic borders, as an onlay graft. There was neither morbidity nor mortality associated to the surgical procedure. No recurrences or long-term complications associated with mesh employment were verified after a follow-up ranging from one year to three years. We concluded that prosthetic repair of incisional hernia in transplanted patients can be performed routinely.

Elective colonic operation and prosthetic repair of incisional hernia: does contamination contraindicate abdominal wall prosthesis use?

BACKGROUND: Wound infection and sepsis leading to incisional hernia development are common after emergency colonic operations. Later on, while being operated on to correct an incisional hernia, most of these patients will need colonic resection or bowel continuity reestablishment. Simultaneous treatment of incisional hernias in patients with colostomy or colonic disease remains a difficult challenge, considering the reluctance of most surgeons to treat both conditions at the same time, especially when prosthetic repair is needed. STUDY DESIGN: The aim of this study was to analyze the short-term results of patients undergoing colonic resection or bowel continuity reestablishment and simultaneous incisional hernia repair with an onlay polypropylene mesh technique. Over a period of 6 years, 20 patients were operated on for colonic problems associated with incisional hernias, including 8 Hartmanns' colostomies, 6 colostomies or ileostomies with colonic mucous fistulas, 3 postoperative colocutaneous fistulas, a paracolostomic hernia, a Chagas' megacolon, and a pseudotumoral diverticulitis. A "rule of three" statistical analysis was used to estimate the maximum risk of adverse effects, concerning mesh-related morbidity, after 1- and 2-year followup. RESULTS: A major complication occurred in a patient who developed an anastomotic leakage and secondary wound infection; the patient was treated with parenteral nutrition and antibiotics. Other complications included a minor wound infection, a seroma, and a chronic sinus. One patient died from postoperative problems unrelated to the surgical technique. The occurrence of postoperative wound infection did not prevent mesh incorporation. Followup ranging from 1 to 7 years detected no hernia recurrences; 13 patients were followed for 2 years or more. Our results suggest that risk of mesh-related morbidity does not exceed 15.8% (3 of 19) within the first year and 23.1% (3 of 13) for 2 years followup, with 95% confidence. CONCLUSIONS: We concluded that prosthetic repair of incisional hernias associated with simultaneous colonic operations was possible, allowing abdominal wall anatomy reestablishment. There is no reason to believe that abdominal wall prostheses must be avoided in contaminated operations when an adequate surgical technique is used.

[Risk factors in emergency surgery relaparotomy]. / Fatores de risco em relaparotomia na cirurgia de urgência.

Reintervention in abdominal surgery involves the difficulty of precise indication and the limitations of surgical technics during the operation. It may bring to evidence professional errors. It presents a very high morbimortality index. In order to establish risk factors and death rate, we comparatively analysed the initial diagnoses, the number, the cause and the time of relaparotomy, the existence of associated diseases, the age and the illness severity, using APACHE-II after the first surgical intervention. During a two years period starting 1990 we retrospectively analysed charts of 40 patients submitted to relaparotomy in the Emergency Service of Hospital das Clínicas of Medicine University of São Paulo.

Síndrome de Fournier: avaliaçäo e tratamento inicial / Fournier syndrome: evaluation and initial treatment

Foram analisados, retrospectivamente, os prontuários de 48 pacientes com síndrome de Forunier atendidos no Serviço de Cirurgia de Emergência do Hospital das Clínicas da Faculdade de Medicina da Universidade de Säo Paulo, no período de 1982 a 1991. Foram analisados os dados clínicos e laboratoriais à admissäo. Os seguintes fatores, associados a um mau prognóstico, foram considerados estatísticamente significativos: elevaçäo da creatinina sérica, hipoxemia, alcalose ou acidose metabólica, diabete e idade maior que 50 anos. Baseados nestes critérios, os pacientes foram divididos em dois grupos: grupo I, forma leve (32 casos) e grupo II, forma grave (16 casos). Acreditamos que esta classficaçäo permita um melhor planejamento da terapêutica. Nos casos classificados como graves, o tratamento deve incluir debridamento amplo, com ressecçäo de todos os tecidos necróticos, reoperaçöes programadas, transversocolostomia, antibioticoterapia de amplo espectro e nutriçäo parenteral total. Nas formas leves, os pacients podem ser tratados com debridamento e antibioticoterapia

[Fournier syndrome: evaluation and initial treatment]. / Síndrome de Fournier: avaliação e tratamento inicial.

The records of 48 patients with Fournier's syndrome (FS) treated at the Emergency Surgical Service of the Hospital das Clínicas of the University of São Paulo Medical School in the period 1982-1991 were reviewed. Clinical and laboratory data at admission were analysed. The following factors were statistically significant when associated with bad prognosis: elevated serum creatinine, hypoxemia, metabolic alkalosis or acidosis, diabetes and age over 50 years. Based on these five criteria, the patients were divided into two groups: Group I, mild FS (32 cases) and Group II, severe FS (16 patients). This classification permits a better planning of therapy. In cases classified as severe, treatment should include wide débridement, with resection of all necrotic tissues, scheduled reoperations for further débridements, transverse colostomy, wide spectrum antibiotic therapy and total parenteral nutrition. In the mild cases, the patients may be treated with débridement and antibiotics only.

[Traumatic wounds of the esophagus]. / Ferimentos traumáticos de esôfago.

Thirty four (75.5%) individuals sustained gunshot wounds, nine (20%) stab wounds, while two (4.4%) suffered blunt trauma. Thirty four patients (75%) displayed severance of the cervical portion of the esophagus, seven (15.5%) of the thoracic segment and only four (8.8%) had injuries on the abdominal portion. The cervical esophagus was surgically approached through oblique left side cervicotomy with primary suture and drainage with Penrose drain. A postero-lateral right side thoracotomy was employed for lesions of the upper and intermediate portion of the thoracic esophagus. When the lower portion of the esophagus was injured, a left side thoracotomy was employed. When the injury involved less than half of the perimeter of the esophagus suturing with ample drainage was adopted. In more extensive injuries involving over half of the perimeter total esophagectomy was the treatment of choice. In abdominal esophageal injuries laparotomy, suture and drainage were performed. Complications occurred in 40% of all patients. Seven patients died though only one from direct consequences of the esophageal injury. The authors believe that an early surgical approach for traumatic esophageal injuries is the best procedure. Primary suture and drainage score the best results. Other measures (esophagectomy, esophagostomy, gastrostomy) should be adopted only when the injury is either extensive or mediastinal contamination is present.

Open pelviperineal trauma.

The authors present their results in the management of 48 patients with complex pelviperineal injuries treated at the Surgical Emergency Ward of the University of São Paulo School of Medicine General Hospital. The distinct factors influencing the morbidity and mortality rates are discussed as well as the importance of an aggressive treatment in the initial approach of these patients. The following steps are virtually essential for the achievement of results comparable to those presented in the present protocol: exhaustive irrigation of the perineal wound with saline solution followed by surgical debridement and removal of all devitalized areas, maintenance of the wound open, early maturation transverse colostomy with total fecal flow diversion, periodic surgical revisions at intervals of 24 to 72 hours, large doses of antibiotic therapy, nutritional support with full parenteral feeding, and appropriate management of bone injuries and skin grafts. Adopting of measures proposed in this protocol yielded a decrease in mortality rate from 70% to 31.5%.

[Perforated duodenal diverticulum: a report of 2 cases]. / Divertículo duodenal perfurado: (apresentação de dois casos).

Two cases of perforated duodenal diverticulum, treated at the surgical Emergency Service of the Hospital das Clínicas of the University of São Paulo Medical School are reported. Although duodenal diverticula are frequent their perforation in is a rare and dougerous complication. Diagnosis and surgical treatment are discussed. We believe that excision, primary suture with an omental patch and drainage are procedures of choice for the treatment of this complication.

[Complex pelviperineal injuries: systematization of the treatment]. / Lesões pelviperineais complexas: sistematização do tratamento.

The authors review the cases of complex pelviperineal injuries admitted to the Emergency Service of the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo during the period 1983-1988. The management of these patients followed a protocol that consisted of: exhaustive lavage of the injury with extensive debridement, leaving the wound widely unsutured, matured loop colostomy, lavage of the distal colon, scheduled revisions at 48 to 72 hour intervals, intensive antibiotic treatment and early total parenteral nutrition. Thirty one patients were treated following these procedures, with a decrease in mortality due to sepsis from 50% to 16.1%.