New-onset Labial Fecal Fistula Secondary to the Incisional Hernia after Appendectomy

A 78-year-old woman with a history of open appendectomy with an uneventful postoperative course at 17 years of age, occasionally presented with redness and swelling in the surgical scar since she was 70 years old, resulting in spontaneous skin ulceration and leakage of a feces-like liquid at age 76. The intestinal wall then gradually prolapsed through the abdominal wall, and became a labial fecal fistula which appeared to be an end stoma after about one year. There was leakage of a feces-like liquid chiefly when the patient was constipated, suggesting that the labial fecal fistula originated from a distal part of the cecum. Diagnostic imaging such as CT and fistulography provided clear evidence to support the presumption. The patient underwent surgery to remove the fecal fistula. A hernia orifice with a diameter of 1 cm existed in the surgical scar after appendectomy. The cecal wall passing through that orifice was resected with the surrounding skin. Histopathological findings showed the continuity between the colonic mucosa and the cutaneous epithelium. Our speculation on the mechanism for the formation of a labial fecal fistula is that the patient had already developed a small cicatricial hernia after appendectomy. At the age of 70, a Richter’s hernia may have occurred at that defect of the abdominal wall resulting in partial necrosis of the cecal wall responsible for recurrent wound infection, leading to eventual formation of a labial fecal fistula.