Published online Oct 26, 2018. doi: 10.12998/wjcc.v6.i12.564
Peer-review started: July 2, 2018
First decision: July 24, 2018
Revised: August 9, 2018
Accepted: August 30, 2018
Article in press: August 31, 2018
Published online: October 26, 2018
A 59-year-old male patient developed mild lower abdominal distention 7 years after repair surgery of a bilateral inguinal hernia. A colonic lesion was found under his endoscopic examination and was suspected to be a polyp. However, the complementary radiological imaging and subsequent endoscopic ultrasonography (EUS) failed to provide enough clues for exact diagnosis. The patient was referred for explorative surgery, during which a prosthetic mesh was confirmed as migrating into the sigmoid colon from its original position. Sigmoidectomy with removal of the mesh was performed. Histological investigations also demonstrated the existence of a foreign body within the affected bowel wall.
Mesh migration into the sigmoid colon after inguinal hernia repair.
Based on the endoscopic and radiological investigations from this case, a colonic polyp caused by migrating mesh should be differentiated from an inflammatory protuberance, malignant neoplasm, atypical colonic diverticulitis or a localized abscess involved in the sigmoid colon. Abdominal distention occurring in the lower abdomen could indicate functional disorders of the intestine, intestinal infection, enteritis, bowel obstruction, habitual constipation, hernia, diseased urinary bladder or gynecological diseases (for women) and so on.
A stool test showed occult blood of 1+. However, there were no positive results from other laboratory tests (e.g., white blood cell, erythrocyte sedimentation rate, peripheral blood culture).
Abdominal computed tomography (CT) showed bowel wall thickening and inflammatory stranding of the colosigmoid junction with bowel gas accumulation and extension of the proximal colon segment. Hyperemic polypoid mucosal lesion was observed in the sigmoid colon via colonoscopy, which was located at approximately 28 cm from the anal verge. EUS identified a cavity-like structure beneath the heterogeneously isoechoic or hypoechoic mucosal lesion.
Chronic mucosal inflammation with components of necrotizing inflammation was confirmed by histological investigation of the endoscopic tissue biopsy from the “colonic polyp”. Pathological features of the surgical specimen showed the substance of the foreign body within the defected bowel wall of the sigmoid colon, along with adjacent inflammatory granulation tissue formation.
Sigmoidectomy with removal of mesh and lysis of the adhesions between lower abdominal wall and colon were performed. The patient received flurbiprofen for postoperative analgesia and prophylactic antibiotics (ornidazole combined with latamoxef) perioperatively. He recovered uneventfully, and abdominal distention was relieved thereafter.
Penetration and erosion of migrating hernia repair mesh into the small bowel, cecum, transverse colon, sigmoid colon, urinary bladder or retroperitoneal region were previously reported in the literature. Most patients complained of abdominal pain and mild tenderness, and pain occasionally increased with food intake. An abdominal mass could be palpable when migrating mesh initiates severe adhesions between viscera. Meanwhile, symptoms including weight loss, anorexia, and fatigue could develop. Bowel obstruction could occur due to intraluminal penetration of migrating mesh.
Mesh migration and penetration into viscera are rare complications after laparoscopic inguinal hernia repair, which could present at different time intervals postoperatively. For the most part, the variable and nonspecific clinical manifestations caused by migrating mesh lead to diagnosis delay. Total removal of the deep-seated prosthetic mesh with organ resection via laparoscopy or laparotomy is first considered and advised in clinical practice. Possible wound sinus or enteric fistulas linked to mesh should be cautiously explored and completely eradicated by excision in combination with drug therapy (antibiotics, somatostatin and parenteral nutrition). Colonoscopic retrieval of intraluminal migrating mesh can be attempted in absence of enteric fistulas.
Mesh migration after inguinal hernia repair is difficult to detect or distinguish via imaging modalities due to the nonradiopaque property of mesh prosthesis. Metal clips or tackers used to fasten mesh are radiopaque but still occasionally missed by internists. In addition, inflammatory tissue formation caused by foreign body can prevent an accurate preoperative diagnosis. Therefore, the case-based learning as well as detailed collection of patients’ medical history provides clinicians with more clues to analyze CT scan with orientation. Overreliance on ultrasonic or radiological investigations occasionally leads to misdiagnosis and missed diagnosis of specific foreign bodies.