Twenty-Year Groin Abscesses Traced to a Rare Appendiceal Fistula

A 64-year-old man experienced recurrent right groin abscesses for more than a decade after a retroperitoneal infection had been drained at another hospital over 20 years earlier. Physicians eventually determined that the repeated abscesses were not a primary groin infection: chronic appendiceal perforation had allowed the cecum to form a fistula through the abdominal wall, creating a persistent communication with purulent drainage in the right inguinal region. A case report of his treatment found that complete laparoscopic removal of the right colon, abscess cavity and fistulous tract was followed by more than two years without recurrence.

The unusual case illustrates how an intra-abdominal source can masquerade as a superficial infection. The man was initially treated with open drainage of a retroperitoneal abscess more than 20 years before the eventual diagnosis. He then developed repeated right inguinal pain, redness, swelling and fever. Across multiple institutions, clinicians repeatedly diagnosed a right iliac fossa abscess and performed incision and drainage. The symptoms temporarily improved after each procedure but returned, and the right groin skin eventually broke down spontaneously and released pus. Records and imaging from the original operation were unavailable, preventing the authors from fully reconstructing how the infection first developed.

On examination, the patient had old surgical scars and a cutaneous opening in the right groin that produced purulent discharge when compressed. Laboratory testing showed mild leukocytosis and an elevated C-reactive protein level. Contrast-enhanced abdominal computed tomography identified a thickened appendix whose margins were poorly defined against the right psoas muscle, surrounding fat stranding, a small amount of fluid, swelling within the psoas and patchy low-density areas. A tubular structure extended inferiorly from the diseased region into the right inguinal subcutaneous tissue, where the adjacent skin was irregular. The imaging was interpreted as chronic appendicitis involving the psoas muscle, with psoas abscess and a possible right lower-quadrant sinus tract.

Sinography provided the decisive evidence for the connection between the abdominal structures and the skin. After iohexol was injected through the right inguinal cutaneous defect, the examination showed a tract associated with the thickened appendix and psoas region. Contrast entered the cecal and appendiceal lumens, directly demonstrating an abnormal communication from the ileocecal region to the abdominal wall. Microbiological culture of the inguinal discharge grew Escherichia coli, supporting an enteric source. Gastroscopy identified chronic atrophic gastritis, while colonoscopy found no ulcers, neoplasms, cecal perforation or diverticula. The preoperative assessment also considered and did not support ulcerative colitis, Crohn’s disease or colorectal cancer.

Before surgery, the clinicians diagnosed chronic appendiceal perforation with a cecal–abdominal wall fistula. Under general anesthesia, the patient underwent laparoscopic right hemicolectomy, intra-abdominal abscess drainage, adhesiolysis and excision of the abdominal wall sinus tract. Dense adhesions beneath the previous incision had trapped the omentum and small bowel, and the bowel in the right lower quadrant was matted together. Exploration found that the appendiceal base and body and part of the adjacent cecum were fixed in the retroperitoneum. A 5-millimeter perforation was present at the appendiceal base, while the cecum, posterior abdominal wall and abscess formed a cavity measuring approximately 3.5 by 3.0 centimeters. A tract could be felt from this cavity to the right inguinal skin defect, confirming the fistula during surgery.

The surgeons removed the right colon, including the ileocecal region and appendix, together with the abscess wall and the full abdominal wall tract, then released the surrounding adhesions. This was not simply another drainage operation. The authors reasoned that drainage or removal of the superficial sinus alone would leave behind the chronically perforated bowel, allowing infection and fistula formation to recur. Histological examination of the right colon, appendix, abscess wall and tract showed chronic inflammation with acute exacerbation, focal mucosal atrophy and shedding, congestion and edema in the lamina propria, and fibrous proliferation on the serosa. No atypical cells, mucin lakes, invasive glandular structures, granulomas, crypt distortion, basal plasmacytosis or transmural lymphoid aggregates were found, providing no morphological evidence of a mucinous neoplasm, cecal adenocarcinoma or Crohn’s disease. The final pathological diagnosis was a cecal fistula caused by chronic appendiceal perforation.

Postoperatively, the patient received nothing by mouth, antibiotics, intravenous fluids, analgesia, acid suppression and nutritional support. He developed paralytic ileus on the third postoperative day, with abdominal distension and absent flatus and defecation. Nasogastric decompression, continued antibiotics and fluid resuscitation produced substantial improvement, and no reoperation was required. The authors described ileus as a possible complication of severe retroperitoneal infection. During follow-up of more than two years, the patient experienced no recurrence of abdominal wall abscess or groin infection and reported excellent quality of life. He also said that more than a decade of recurrent swelling and discharge had affected his daily life and led to repeated hospital visits and drainage procedures, while anxiety about recurrence remained until surgery.

The delayed diagnosis appears to have depended on both the anatomy of the infection and the way it presented. Chronic appendiceal perforation rarely produces the familiar pattern of acute diffuse peritonitis or sepsis. When the appendix and cecum occupy a retroperitoneal position, inflammatory material can spread into the psoas, iliac fossa or other retroperitoneal spaces without spilling freely into the peritoneal cavity. An abscess may then track along the psoas fascia, pass through the abdominal wall into inguinal subcutaneous tissue and repeatedly open at the skin. In this patient, the disease was substantially confined to the retroperitoneum, with recurrent groin drainage serving as the main outward sign rather than typical appendiceal symptoms. The abscess cavity and its tract connected the perforated cecum to the groin, explaining why repeated local drainage did not remove the source.

Cross-sectional imaging is central to identifying this anatomy, while sinography through the external opening can establish the internal communication. CT can display the appendix, psoas involvement, abscess and suspected tract, and the reported case demonstrates the value of adding contrast sinography when the tract is clinically apparent. The authors noted that dense material visible in the cecum and appendiceal lumen might represent fecaliths or concentrated contrast, further supporting a chronic perforation, although imaging alone could not establish the complete diagnosis. They also highlighted the need to consider an appendiceal or cecal mucinous neoplasm, cecal adenocarcinoma and Crohn’s disease in a chronic inflammatory mass involving the ileocecal region and a long-standing fistula. In this patient, CT, endoscopy, operative findings and histopathology excluded those alternatives.

Because this was a single-patient case report, it cannot establish how frequently chronic appendiceal perforation causes a cecal–abdominal wall fistula or whether complete resection will produce similar outcomes in other patients. The missing early records further limit reconstruction of the initial pathophysiological process, and no standardized patient-reported outcome measures were collected. The report also notes that chronic appendiceal perforation has no widely accepted diagnostic criteria, that it accounts for less than 1% of appendiceal perforations in the cited large series, and that the available literature consists mainly of isolated reports, usually involving courses shorter than one year. The authors identified fragmented records, repeated care at different institutions, anchoring on a diagnosis of primary groin abscess or postoperative sinus, and possible limited access to advanced imaging as factors that may have prolonged the diagnostic delay. For this patient, however, integration of CT, sinography, operative exploration and pathology established the cause, and en bloc removal of the involved bowel, abscess and tract produced a sustained recovery.

Subject of Research: A rare case of chronic appendiceal perforation causing a cecal–abdominal wall fistula and recurrent groin abscesses.

Article Title: Chronic appendiceal perforation leading to cecal–abdominal wall fistula long misdiagnosed as recurrent groin abscess: a rare case report

Article References: Li, J., Liu, W.-N., Jiang, Z.-H., Xiong, H.-B., Deng, L.-B., & Deng, L.-H. (2026). Chronic appendiceal perforation leading to cecal–abdominal wall fistula long misdiagnosed as recurrent groin abscess: a rare case report. Frontiers in Medicine, 13, Article 1901981. https://doi.org/10.3389/fmed.2026.1901981

Image Credits: AI Generated

DOI: 10.3389/fmed.2026.1901981

Keywords: chronic appendiceal perforation, cecal fistula, abdominal wall fistula, recurrent groin abscess, psoas abscess, sinography, laparoscopic hemicolectomy, case report, Chronic, appendiceal, perforation, leading