Incidence of mesh infection after reconstruction of abdominal incisional hernia is known to be higher than that of inguinal hernia. Although several cases of acute-onset mesh infection after abdominal incisional hernia reconstruction were reported, very few reports can be found concerning late-onset (here, we defined "late" as above 6 months after previous hernia repair) mesh infection. Only three cases were found to be reported including descriptions of the details of the case progress [2,3,4]. In 2006, Jezupovs et al. reported, in their retrospective analysis of 375 patients applying polypropylene mesh, a case of polyfilament mesh infection developed 18 months after recurrent incisional hernia repair followed by right subtribe laparotomy [2]. After 1-month unsuccessful abscess drainage, the 77-year-old man underwent partial removal of the Citrobacter koseri-infected mesh. No description was found how the reconstruction was performed in the report. In the same year, Bliziotis et al. presented a 59-year-old female case of late-onset mesh infection developed 6 months after hypogastric abdominal hernia repair followed by an ovarian cancer operation 2 years prior [3]. S. aureus was identified in his abscess contents. Initial 7 days antibiotic management failed, and removal of mesh combined with 2-week antibiotic medication led to the cure of infection. Unfortunately, details of the reconstruction were either not described. In 2016, Mohamed et al. reported a 44-year-old woman case of huge seroma formation diagnosed 5 years after ventral incisional hernia repair [4]. She underwent an open Roux-en-Y gastric bypass surgery and umbilical hernia repair 7 years prior, and a ventral incisional hernia repair using composite mesh 2 years later. Five months of conservative management led to evidence of highly resistant Pseudomonas aeruginosa infection, and she underwent mesh explantation and definitive repair with complex abdominal reconstruction combined with macroporous monofilament synthetic mesh and porcine dermal graft.
These rare cases may propose us at least two important points of discussion concerning delayed mesh infection after ventral hernia repair. First is that what causes delayed mesh infection after abdominal incisional hernia repair. At least three mechanisms can be supposed as follows: (i) remnant infection related to previous operation accompanying with contamination (which might be in association with bacterial biofilm formation on mesh), (ii) bacterial translocation followed by some kind of septic events, and (iii) de novo infection, either by mesh-intestine fistula formation or by transcutaneous. Given the four case reviews, the main cause of delayed mesh infection seems retrograde transcutaneous infection arising from prolonged drainage, accompanying bacterial biofilm, by two facts. One is that all four previous operations were performed in clean, or at least in semi-clean, conditions, and no septic event was observed in their past medical history. The other is that the types of cultured bacteria (C. koseri, P. aeruginosa, and S. aureus) are known to produce rich biofilm and to cause secondary remnant infection. Another point of discussion is how to manage delayed mesh infection after ventral hernia repair. It is possible to recommend avoiding prolonged conservative treatments including lavage and drainage when highly biofilm-associated bacteria were identified from the seroma/abscess contents. Additionally, as all four infected meshes were removed, mesh removal seems essential to treat delayed mesh infection in terms of biofilm debridement. However, the decision of mesh removal may often be hesitated by technical reasons especially when primary closure seems difficult or impossible due to huge intramuscular defect after mesh removal. Components separation technique application, which is described in the present case, can be of great help of designing reconstruction after removal of infected mesh for such cases. This technique is first introduced in 1990 by Ramirez et al. [5], of which the principle is basically bridging the fascial gap by separating fascial and muscular layers without using prosthetic meshes. Defects up to 20 cm in diameter can be reconstructed in a “tension-free” condition maintaining physiological abdominal wall function. Although recurrence rate is relatively high compared to mesh repair, this technique is still attractive especially in contaminated cases when mesh application should be avoided.