Appendicitis epiploicae is a rare entity. The relative incidence compared to acute vermiform appendicitis is 0.2%.4
Appendices epiploicae are pendulous adipose structures protruding from the serosal surface of the large intestine that are arranged in two separate longitudinal rows. Each of them is supplied by one or two small end arteries branching from the long vessels of the colon and drained by a tortuous vein passing through a narrow pedicle. Their limited blood supply, together with their peduncle shape and excessive mobility, make them prone to spontaneous torsion and ischaemic or haemorrhagic infarction.5
Appendices epiploicae may become infarcted as a result of venous thrombosis. The process of the inflammatory reaction that follows acute torsion or spontaneous thrombosis of the draining vein is called primary appendicitis epiploicae.6
Appendices epiploicae are also affected by calcification due to aseptic fat necrosis, pericolic abscess, enlargement by lipomas or metastases, and incarceration in hernias.7
The clinical presentation of an acute torsion can also mimic acute appendicitis, diverticulitis or cholecystitis.8
Symptoms may be minimal and there is no diagnostic sequence of symptoms. The most common presenting symptom is acute, moderate to severe, colicky or continuous abdominal pain in an area corresponding to the contour of the colon, and pain shift is unusual. The pain is usually present for less than a week, but in some patients it may occur intermittently over several months.1
The patient does not look ill, nausea and vomiting are unusual, and appetite is commonly unaffected. Localised tenderness over the site is usual and is often associated with pronounced rebound tenderness without rigidity.
Laboratory investigations have been found to be inconclusive, and usually suggest a normal or slightly elevated leucocyte count.2,3
The radiological evaluation in the form of abdominal ultrasound examination and computed tomography (CT) scan has been found to be useful in the preoperative diagnosis in patients with appendicitis epiploicae. A review of the literature suggests that the presence of a hyperechoic non-compressible ovoid structure near the colonic wall with the absence of blood flow on sonographic assessment of the abdomen provides the clue to the diagnosis.2
Similarly, CT scan has been found to be useful both for preoperative diagnosis and for further assessment in patients managed conservatively. As stated above, a correct preoperative diagnosis is rarely made.9
There are no pathognomonic features of primary appendicitis epiploicae, and it may be encountered by the surgeon while performing a laparotomy for another condition.1
The treatment of choice for primary appendicitis epiploicae consists of simple ligation and excision.9
If a preoperative diagnosis is made, conservative treatment with antibiotics and analgesics seems to be safe.2
- Appendicitis epiploicae is a rare entity.
- Appendicitis epiploicae is often diagnosed by the surgeon while performing a laparotomy for another condition.
- The torsion of appendices epiploicae may be seen in all the colonic segment, but it usually originates from the sigmoid colon and rarely from the caecum.
- The treatment of appendicitis epiploicae is initially conservative, if diagnosed preoperatively. If an intraoperative diagnosis is made, the surgical treatment of appendicitis epiploicae is simple ligation and excision.