De Garengeot’s hernia: a rare and challenging clinical entity. Case report and review of the literature

A 71-year-old woman presented to the emergency room with a 1-week history of right groin pain and bulge. The patient denied nausea, vomiting, and fever; the bowel movements were normal. The vital signs were normal, with heart rate 88 beats/minute, blood pressure 110/80 mm Hg, SpO₂ 98% and temperature 37°C. At examination, a right inguinal bulge was observed, with moderate tenderness to palpation and no inflammation signs. The bulge couldn’t be reduced. Guarding and rebound tenderness were absent. The rest of the physical exam was unremarkable. A bedside US was performed, which showed a right femural hernia containing the appendix, surrounded by anechoic fluid and fat stranding (Figure 1). The laboratory exams showed a blood cell count of 10.680 per mm³ and an elevation of C-reactive protein (102 mg/L). A CT scan of the abdomen confirmed the suspected diagnosis of De Garengeot’s hernia (Figure 2 & 3). Therefore, the patient was taken to the operation room for laparoscopic exploration. The herniated appendix wasn’t reducible in the abdominal cavity by traction. An incision was made superior to the inguinal ligament and the hernia was successfully reduced. The appendix was congested and inflamed; the caecum was normal. Thereafter, laparoscopic appendectomy and right hernia repair with a prolene mesh were performed (Figure 4). The patient recovered well and was discharged home on the third post-operative day. The pathological exmination of the appendix showed evidence of acute inflammation.

Methods
A literature review was conducted in March 2025 by searching the PubMed database. The search strategy included the keywords “De Garengeot’s hernia”, “appendix in hernia sac”, and “rare hernia”, focusing on publications in english. In addition, the references of selected articles were examined to identify further relevant sources. From an initial pool of 982 publications, 155 were used and 28 consulted for this review.

Epidemiology and physiopathology
De Garengeot’s hernia is rare, occurring in 0,5-5% of adult femural hernias that undergo surgical repair [1,2]. Despite low incidence, the surgeon should always consider the possibility of encountering an appendix in the hernia sac, particularly during a scheduled hernioplasty, to avoid complications related to possibile inflammation or ischemia of the appendix [3,4]. De Garengeot’s hernia is predominantly observed in female patients, the mean age at presentation being 69 years; however, pediatric cases and occurrences in males have also been reported [1].The pathophysiological mechanism is not fully understood. One proposed congenital explanation is that the intestinal malrotation makes the caecum lying low in the pelvis, so increasing the likelihood of the appendix entering the femoral canal. Another hypothesis suggest that a longer appendix can enter the femoral canal more easily. Alternatively, a large mobile caecum can push the appendix towards the femoral canal [1,2]. The appendix in the De Garengeot’s hernia sac frequently shows signs of inflammation and/or necrosis, because of the extra-luminal compression in a narrow site [5].

Clinical presentation
Patients with De Garengeot’s hernia exibit signs and symptoms similar to those of a standard inguinal hernia, such as groin swelling, variable pain, and signs of inflammation [6,7].

Groin swelling: A noticeable bulge in the inguinal region that increases with Valsalva maneuvers (e.g., coughing), and may reduce in supine position.

Pain: Pain may be mild if the appendix is not inflamed, or severe, in event of acute appendicitis.

Inflammation: In cases with acute appendicitis, fever, intense pain, and local peritoneal signs (guarding, rebound tenderness) can occur.

In many instances, the diagnosis of De Garengeot’s hernia is an incidental finding during inguinal hernia repair. However, in patients presenting with a complicated inguinal hernia (e.g., strangulated or incarcerated), appropriate preoperative imaging can reveal the presence of the appendix in the sac [8].

Diagnosis
Clinical examination: On physical examination, one may suspect an incarcerated or strangulated hernia, especially if there is severe pain and the hernia sac can’t be reduced. Sometimes there is evidence of inflammatory skin changes [9,10]. However, it’s rarely possible to confirm the presence of the appendix by examination alone [11-13].

Imaging
Ultrasound: Groin US may detect an atypical tubular structure within the hernia sac. In the event of appendicitis, the appendix will be non-compressible, with thickened walls and increased blood flow in color doppler [14,15].

Computed tomograph: CT of the abdomen and pelvis with contrast medium is the most sensitive diagnostic method. It can identify the appendix in the hernia sac and assess signs of inflammation (e.g., fat stranding and fluid collection) [16-19]. Preoperative identification of De Garengeot’s hernia is critical for planning the surgical strategy, allowing the surgeon to be prepared for a possible appendectomy or more complex repair.

Classification: Guenther and coll. in 2021 proposed a classification system, which categorized De Garengeot’s hernia based on the degree of the appendiceal inflammation [1].

Type 1: normal appendix within the hernia sac
Type 2: erythema, inflammation or congestion of the appendix
Type 3: necrosis of the appendix
Type 4: necrosis of the appendix and of the caecum

 Surgical approaches: Surgical strategy varies depending on the type, including whether or not to perform an appendectomy, the use of tension-free or mesh repair, and the choice of biologic or syntetic mesh.

Open surgery: The most traditional approach is open repair via an inguinal incision. If the appendix is macroscopically normal (type 1), many surgeons prefer to leave it in place and perform a standard hernia repair with a prostetic mesh, given the low risk of infection.  Conversely, if the appendix is inflamed (type 2 or higher), appendectomy is performed, often followed by a direct tissue repair or the placement of a biological mesh to reduce the risk of prosthetic infection [20-22].

Laparoscopic surgery: In recent years, laparoscopic repair has become more common, providing direct visualization of the abdominal cavity and ruling out other pathologies. Laparoscopic surgery should be considered in stable patients, especially if the diagnosis is known preoperatively. In cases of confirmed appendicitis, laparoscopy may allow for a minimally invasive appendectomy, although in emergencies operating times and technical complexity can increase. Furthermore, the laparoscopic approach allows to evaluate the rest of the abdomen (most importantly, the caecum) [23-25].

Controversy on the use of mesh: A highly debated point is the use of prosthetic mesh in the presence of an inflamed appendix. Some authors argue that placing prosthetic material in a potentially contaminated surgical field carries a risk of infection and related complications (e.g, chronic infection, fistula, mesh erosion). Others maintain that, under controlled conditions, and with adequate antibiotic coverage, an appendectomy plus the use of biological, next-generation meshes can still be performed, although this decision remains a case-by-case assessment [26].

Results: The prognosis for patients undergoing surgical repair of De Garengeot’s hernia is generally favorable, provided the operation is performed promptly, especially when appendicitis is present. Possibile complications include:

Wound infection: Mainly a concern when prosthetic material is used in the setting of active infection.

Mesh-related complications: Chronic pain, mesh erosion, or fistula formation in cases of persistent infection.

Recurrence: Recurrence rates are similar to those for standard inguinal hernia repair, unless only suture repair is performed in the presence of acute appendicitis, which may increase the risk of this complication.

Adequate intraoperative recognition, appropriate case classification, and a tailored surgical strategy (including the choice of whether to remove a normal appendix [27], the prudent use of prosthetics, and proper antibiotic prophylaxis) reduce these complications [28]. Post-operative follow-up includes regular clinical evaluations and imaging if suspicious symptoms arise.