Late-Onset Mesh Infection 10 Years After Right Inguinal Hernia Repair: A Case Report

Introduction

Mesh infections are generally classified according to the timing of onset into early- or late-onset infection, occurring postoperatively within 1 month or later, respectively [1]. This distinction is crucial for identifying the infection source and appropriate treatment strategies. Early-onset infections are primarily associated with intraoperative contamination, whereas late-onset infections are frequently related to factors such as immunosuppression or fistula formation. Late-onset inguinal hernia mesh infection is rare [2], with symptoms including chronic pain, visible scars, and red, swollen, and tender skin.

Currently, standardized treatment protocols for late-onset mesh infections remain unavailable. Some case reports indicate achieving complete healing without mesh removal [3,4]. However, most studies reveal that effective postoperative mesh infection management generally requires a combination of abscess drainage, infected organ resection, and complete mesh removal [5].

Case Report

ETHICS APPROVAL AND CONSENT TO PARTICIPATE:

This study was conducted in accordance with the principles of the Declaration of Helsinki. The Institutional Review Board for Clinical Research of Yachiyo Hospital waived the need for ethics approval. Informed consent to participate in study was obtained from the patient.

Discussion

Various factors, including surgical site or mesh contamination and patient-specific conditions that increase susceptibility to infection, such as diabetes or steroid use, cause mesh infection. Secondary factors, such as fistula formation involving adjacent organs, such as the appendix or sigmoid colon, have also been frequently reported in case studies. Mesh infections are categorized according to the time of onset after hernia surgery. Generally, infections occurring within 1 month postoperatively are classified as early-onset infections, whereas those occurring afterward are categorized as late-onset infections [1].

This case represents a late-onset mesh infection that developed 10 years postoperatively. Notably, the incidence of late-onset mesh infection is extremely low, with a reported occurrence of only 0.06% [6]. Considering the extended period of uneventful postoperative recovery, mesh infections are highly unlikely to develop without an underlying trigger. Case reports of late-onset mesh infections are occasionally documented, but most involve abscess formation due to fistula development with surrounding organs.

Typically, the mesh is placed in the preperitoneal space, thereby minimizing direct contact with surrounding organs. However, inadequate mesh fixation or incomplete peritoneal closure can cause the mesh to come into direct contact with adjacent organs or be subjected to significant tension, potentially causing fistula formation [7–9]. Hernia repair was performed with the PHS method in this case. However, reports of fistula formation between the mesh and surrounding organs have also been documented after other surgical techniques, including the mesh plug and Lichtenstein methods [10,11].

In the present case, a retrospective review of an abdominal CT scan performed approximately 8 years prior revealed adhesion between the tip of the appendix and the right lower abdominal wall. We hypothesized that, over time, the development of a cecal tumor caused appendiceal orifice stenosis, gradually forming a fistula between the appendix and the mesh. This prolonged pathological process likely contributed to the late-onset mesh infection observed in this patient, occurring approximately 10 years postoperatively – an interval significantly longer than that of previously reported cases [12].

In the case of our patient, the appendix and the peritoneum in the right inguinal region were tightly adhered, requiring partial peritoneal resection. Consequently, the resulting peritoneal defect caused mesh exposure to the abdominal cavity. However, no pus discharge was observed intraoperatively; thus, the mesh was not removed, and the procedure was completed by closing the defect. However, postoperative mesh infection persisted, ultimately requiring reoperation and continuous negative-pressure drainage therapy.

Currently, definitive treatment protocols for late-onset mesh infections remain unavailable, and some case reports indicate that healing occurs without mesh removal [4]. However, most reports indicate that effective postoperative mesh infection management generally requires abscess drainage, infected organ resection, and complete mesh removal [5]. In the present case, the treatment period was prolonged because the mesh was not removed initially. Further, some reports indicate that mesh removal poses a low risk of chronic inguinal pain or hernia recurrence [13,14]. It is also reported that mesh removal should be considered if conservative treatment fails to improve symptoms after approximately 1 month [2]. These results indicate that proactive consideration of mesh removal during the initial surgery may have been warranted in our case [1].

Moreover, by applying vacuum-assisted wound therapy, negative pressure enables continuous drainage of exudate and infectious materials such as pus from the wound, thereby reducing conditions favorable for bacterial growth. It also improves local blood flow, promotes granulation tissue formation, and facilitates early wound healing while preventing secondary infection. In our patient, 2 additional operations were required to remove the residual mesh. Although complete mesh removal was intended during the first operation, residual mesh remained, resulting in persistent pus discharge. This may have occurred because we did not perform the laparoscopic and anterior approaches for mesh removal simultaneously, but used only the anterior approach. In particular, because the PHS places mesh in both the preperitoneal space and along the posterior wall of the inguinal canal, the use of both approaches would have been effective in achieving more reliable complete mesh removal. Therefore, during the initial laparoscopic ileocecal resection, the mesh located in the preperitoneal space should have been removed laparoscopically, followed by anterior removal of the mesh placed in the inguinal canal.

Conclusions

We present a case of mesh infection after hernia surgery, which presented significant treatment challenges. Inguinal hernia mesh infections are rare; however, if they do occur, mesh removal is recommended whenever possible. Complete removal of the mesh is essential for the cure of infection; however, this can be extremely difficult in certain cases. Surgical strategies should be adapted to the characteristics of the implanted mesh, and in cases involving the PHS, laparoscopic and anterior approaches are required to achieve complete removal.

Late-onset mesh infection can occur long after hernia repair and should be considered in the differential diagnosis. A standardized treatment protocol for these infections is needed in the future.