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.

The European Hernia Society Prehabilitation Project: a systematic review of patient prehabilitation prior to ventral hernia surgery

BACKGROUND

Ventral hernia repair is one of the most commonly performed surgical procedures worldwide. To reduce the risk of complications, patient prehabilitation has received increasing focus in recent years. To assess prehabilitation measures, this European Hernia Society endorsed project was launched. The aim of this systematic review was to evaluate the current literature on patient prehabilitation prior to ventral hernia repair.

METHODS

The strategies examined were optimization of renal disease, obesity, nutrition, physical exercise, COPD, diabetes and smoking cessation. For each topic, a separate literature search was conducted, allowing for seven different sub-reviews.

RESULTS

A limited amount of well-conducted research studies evaluating prehabilitation prior to ventral hernia surgery was found. The primary findings showed that smoking cessation and weight loss for obese patients led to reduced risks of complications after abdominal wall reconstruction.

CONCLUSION

Prehabilitation prior to ventral hernia repair may be widely used; however, the literature supporting its use is limited. Future studies evaluating the impact of prehabilitation before ventral hernia surgery are warranted.