Autoimmunity and hernia mesh: fact or fiction?

BACKGROUND: There is an increasing number of patients following hernia surgery with implanted mesh reporting symptoms that could indicate autoimmune or allergic reactions to mesh. 'Allergy' to metals, various drugs, and chemicals is well recognised. However, hypersensitivity, allergy or autoimmunity caused by surgical mesh has not been proven by a scientific method to date. The aim of this study was twofold: to describe the pathophysiology of autoimmunity and foreign body reaction and to undertake a systematic review of surgical mesh implanted at the time of hernia repair and the subsequent development of autoimmune disease. METHODS: A systematic review using the PRISMA guidelines was undertaken. Pubmed (Medline), Google Scholar and Cochrane databases were searched for all English-written peer-reviewed articles published between 2000 and 2021. The search was performed using the keywords "hernia", "mesh", "autoimmunity", "ASIA", "immune response", "autoimmune response". RESULTS: Seven papers were included in the final analysis-three systematic reviews, three cohort studies and one case report. Much of the current data regarding the association of hernia mesh and autoimmunity relies on retrospective cohort studies and/or case reports with limited availability of cofounding factor data linked to autoimmune disease such as smoking status or indeed a detailed medical history of patients. Three systematic reviews have discussed this topic, each with a slightly different approach and none of them has identified causality between the use of mesh and the subsequent development of autoimmune disease. CONCLUSION: There is little evidence that the use of polypropylene mesh can lead to autoimmunity. A large number of potential triggers of autoimmunity along with the genetic predisposition to autoimmune disease and the commonality of hernia, make a cause and effect difficult to unravel at present. Biomaterials cause foreign body reactions, but a chronic foreign body reaction does not indicate autoimmunity, a common misunderstanding in the literature.

Liquid resorbable nanofibrous surgical mesh: a proof of a concept.

BACKGROUND: Surgical mesh is widely used not only to treat but also to prevent incisional hernia formation. Despite much effort by material engineers, the 'ideal' mesh mechanically, biologically and surgically easy to use remains elusive. Advances in tissue engineering and nanomedicine have allowed new concepts to be tested with promising results in both small and large animals. Abandoning the concept of a pre-formed mesh completely for a 'pour in liquid mesh' has never been tested before. MATERIALS AND METHODS: Thirty rabbits underwent midline laparotomy with closure using an absorbable suture and small stitch small bites technique. In addition, their abdominal wall closure was reinforced by a liquid nanofibrous scaffold composed of a fibrin sealant and nanofibres of poly-ε-caprolactone with or without hyaluronic acid or the sealant alone, poured in as an 'onlay' over the closed abdominal wall. The animals were killed at 6 weeks and their abdominal wall was subjected to histological and biomechanical evaluations. RESULTS: All the animals survived the study period with no major complication. Histological evaluation showed an eosinophilic infiltration in all groups and foreign body reaction more pronounced in the groups with nanofibres. Biomechanical testing demonstrated that groups treated with nanofibres developed a scar with higher tensile yield strength. CONCLUSION: The use of nanofibres in a liquid form applied to the closed abdominal wall is easy to use and improves the biomechanical properties of healing fascia at 6 weeks after midline laparotomy in a rabbit model.

Treatment of anastomotic leak after Ivor Lewis esophagectomy.

INTRODUCTION: Anastomotic leak (AL) is one of the most serious surgical complications after esophagectomy. Endoscopic, radiological and surgical methods are used in the treatment of AL. The aim of this study was to retrospectively evaluate our therapeutic procedures and results of AL treatment after Ivor Lewis esophagectomy (ILE). METHODS: Retrospective audit of all ILEs performed in the years 20052019. Evaluation of AL treatment results according to Esophagectomy Complication Consensus Group (ECCG) classification and according to the primary therapeutic procedure with a focus on the treatment with esophageal stent. RESULTS: Out of 817 patients with ILE, AL was detected in 80 patients (9.8%): ECCG type I 33 (41%), type II 23 (29%) and type III 24 (30%) patients. Some 33 patients (41%) were treated conservatively. Esophageal stents were used in 39 patients (49%), of which 18 (23%) had concomitant percutaneous drainage and 17 (21%) were reoperated. Reoperation without a stent insertion was performed in 7 patients (9%). Esophageal diversion with cervical esophagostomy was performed in a total of 16 patients (20%). Esophageal stent treatment was successful in 24/39 patients (62%). Airway fistula occurred in 4 patients treated with stent (10%). Endoscopic vacuum therapy was successfully used in three patients after stent failure. Eight patients (10%) died as a result of AL. Mortality of AL type I, II and III was 0%, 4% and 29%. CONCLUSION: Successful treatment of AL requires an individual and multidisciplinary approach. The primary effort should aim to preserve anastomosis using endoscopic and radiological methods. In case of insufficient clinical effect, we recommend not to hesitate with reoperation. If primary therapy fails, the life-saving procedure is a cervical esophagostomy.