DOI:10.24938/kutfd.529130 Kırıkkale Üniversitesi Tıp Fakültesi Dergisi 2019;21(1): 102-107 Review Derleme THE INFLAMMATION OF EPIPLOIC APPENDIX: PRIMARY EPIPLOIC APPENDAGITIS Epiploik Apendiks Enflamasyonu: Primer Epiploik Apandajit Sevilay VURAL1, Figen COŞKUN2 1Yozgat Bozok Uygulama ve Araştırma Hastanesi, Acil Tıp A.D., YOZGAT, TÜRKİYE 2Dokuz Eylül Üniversitesi Tıp Fakültesi, Acil Tıp A.D., İZMİR, TÜRKİYE ABSTRACT ÖZ Epiploic appendices are extensions of omentum which covers most Epiploik apendiks kolonun çoğunu kaplayan omental of the colon. Most of the pathologic changes are related with uzantılardır. Patolojik değişikliklerin çoğu spontan torsiyon spontaneous torsion or venous thrombosis culminating with veya venöz tromboz sonrası oluşan enflamasyon ile inflammation and is referred as primary epiploic appendagitis ilişkilidir ve primer epiploik apandajit olarak adlandırılır. (PEA). There is no pathognomonic symptom, finding or laboratory Nispeten nadir görülen bu intra-abdominal patoloji için test for this relatively rare intra-abdominal inflammation. A non- herhangi bir patognomonik semptom, bulgu veya toxic patient with acute onset localized abdominal pain in the right laboratuvar testi yoktur. Sağ veya sol alt kadranda akut or left lower quadrant is the typical presentation. Imaging studies başlangıçlı lokalize karın ağrısı olan non-toksik such as ultrasound and tomography with the awareness of PEA in görünümdeki hasta tipik prezentasyondur. İntra-abdominal differential diagnoses of intra-abdominal pathologies are the key to patolojilerin ayırıcı tanısında primer epiploik apandajit correct diagnosis. Since the conservative treatment is sufficient in farkındalığı ile ultrason ve tomografi gibi görüntüleme most of cases, accurate and timely diagnosis can ensure the çalışmaları doğru tanı koymada anahtar role sahiptir. appropriate patient management and can prevent unnecessary Konservatif tedavi çoğu durumda yeterli olduğundan doğru hospitalizations and interventions. ve zamanında tanı ile uygun hasta yönetimi sağlanıp gereksiz hastane yatışları ve girişimler önlenebilir. Keywords: Appendix epiploica, appendagitis, fat necrosis, Anahtar Kelimeler: Apendiks epiploica, apandajit, yağ acute abdomen, differential diagnosis nekrozu, akut batın, ayırıcı tanı Correspondence / Yazışma Adresi: Dr. Sevilay VURAL Harbiye Mah. Dikmen Cad. 118/2, Ankata, ANKARA, TÜRKİYE Phone / Telefon: 05063669227 E-mail / E-posta: [email protected] Received / Geliş Tarihi: 23.02.2019 Accepted / Kabul Tarihi: 13.03.2019 ORCID NO: 10000-0002-1722-7987, 20000-0002-7027-8169 KÜTFD | 102 Vural S and Coşkun F. KÜ Tıp Fak Derg 2019;21(1):102-107 Primary Epiploic Appendagitis Doi:10.24938/kutfd.529130 INTRODUCTION or cholecystitis, the main focus of our review will cover primary epiploic appendagitis (PEA) (6,7). There are many alternatives in nomenclature for epiploic appendix (EA) like epiploic appendices, PEA results from spontaneous torsion of the EA or appendices epiploicae, epiploic appendages, appendix thrombosis of the venule of the EA followed by epiploica, or omental appendices. The medical ischemic or haemorrhagic infarction and inflammation. definition of “epiploic” is omental or associated with The histopathologic investigations generally reveal the omentum, and “appendage” relates to extensions or necrosis in adipose tissue, haemorrhage and a smaller part that is attached to something larger or lymphoplasmatocytic infiltrate without involvement of more important. EA can be described as omental fatty bowel wall. The PEA may also detach from the extensions that distribute on the external surface of omentum and become a loose intraperitoneal body as colon from the cecum to the rectosigmoid junction. Virchow suggested in 1853. The embryology and anatomy of EA have been Clinical Manifestations described firstly by Vesalius in 1543 (1). The The typical age range for PEA is found as 12-76 years cumulative knowledge from that time reveals much with a peak of incidence at the age of 40 years with more detailed anatomical features. For example, an male gender dominancy (2,8-10). The literature average adult body contains high number of these incidence ranges between 1,65-7,1% in cases of acute structures as many as 50-100 (2). They are generally 1- abdominal pain (8,11-13). The reported colonic 2 cm thick and 0.5-5 cm long, but they can be involvement sites for PEA are mainly indicating the extremely long up to 15 cm (3). They originate from sigmoid colon and the cecum respectively as EAs are anterior and the posterior taenia coli and are localized larger in size and more abundant on the left side of the throughout the external surface of the whole colon colon compared to the right side (2,7,8,11). PEA is an while the majority are found around the sigmoid colon extremely rarer entity in the paediatric age group (14). and the caecum. They have a limited circulation system Some risk factors like obesity, sudden weight loss and that consists of 1 or 2 arterioles and a small draining strenuous exercise are defined, however without a clear vein within a stalk, with or without lymphatic drainage. mechanism. This is still a subject to debate The pedunculated shape, excessive mobility and (2,9,13,15). limited blood supply make EA prone to ischemia The time between the onset of the symptoms and the and/or torsion. The function of EA is not certain but the admission to the hospital can be 4 hours-7 days bacteriostatic potential, being a part of colonic (2,8,13). The general appearance of the patients with absorption and mechanical protection of the colon are PEA is not indicative of any toxins. A localized the most advocated theories (4,5). abdominal pain lasting less than one week is the mostly EA pathologies are a rare cause of acute abdominal observed symptom in patients as opposed to anorexia, pain. EAs are mainly affected by spontaneous torsion, nausea fever or vomiting. Pain is localized, steady, primary or secondary inflammation, thrombosis, non-migratory, non-radiating with an intensity of 4-8 in calcification and strangulation in hernias. The most the visual analogue scale (VAS) and the rating may be common pathology is a self-limiting condition called increased by coughing, deep breathing or stretching epiploic appendagitis, which can be primary or due to the proximity with adherent parietal peritoneum. secondary. While secondary epiploic appendagitis The physical examination generally reveals a localized develops following the inflammatory processes in abdominal tenderness which can be right-sided or left- adjacent structures, such as in cases of any intra- sided, sometimes associated rebound (≤25%) or abdominal inflammation like appendicitis, diverticulitis KÜTFD | 103 Vural S and Coşkun F. KÜ Tıp Fak Derg 2019;21(1):102-107 Primary Epiploic Appendagitis Doi:10.24938/kutfd.529130 abdominal mass, but abdominal rigidity is not expected such as its relative low cost, lack of ionizing radiation (8-10,16-17). Fever, especially higher than 38.0°C is and its portable nature, but it is highly operator- rarely seen contrary to expectations (2,8-10). dependent. As the interpretation of US is challenging The blood tests are not very useful as leukocytosis and the findings are not very stable, physicians (12.9%) and bandemia are relatively rare and the other generally prefer CT as the first imaging choice or as the inflammatory markers are normal compared to other second choice after US to confirm the diagnosis. common intra-abdominal pathologies (2,8,9). PEA on CT appears as an oval fatty mass less than 5 The differential diagnosis of PEA should include acute cm in diameter which has slightly higher attenuation appendicitis, diverticulitis, cholecystitis, haemorrhagic than the peritoneal fat adjacent to the colon, mostly ovarian cyst, ovarian torsion, ectopic pregnancy, with perilesional inflammatory changes. The CT colorectal cancer and mesenteric lymphadenitis. It is appearance of PEA has some characteristic radiological not surprising that PEA is mostly misdiagnosed as findings like “the hyper-attenuating ring sign” and diverticulitis and acute appendicitis due to their higher “central dot sign”. The “central dot sign” also known incidence and the shared location of pain. In a study as the ‘‘dense central vessel sign’’ is attributed to with 660 cases suspected of having appendicitis or engorged or thrombosed vascular pedicle within the diverticulitis, only 2% of them were found positive for inflamed epiploic appendage. Although it is highly PEA (11). Considering that PEA is not generally pathognomonic for PEA, it cannot be observed in all preferential for the presumptive diagnosis of acute patients (21,22). Conversely, the hyperattenuating ring abdomen, it should be included in differential sign is a more frequent imaging feature. It forms due to diagnoses of these more common conditions. serosal oedema that encloses a well-defined rounded or ovoid focus of paracolic fat (21-24). A lobulated appearance is possible and calcification within the DIAGNOSIS infarcted lesion may be seen in time. The CT findings Since the clinical presentation is nonspecific and the are expected to resolve in 6 months after the acute lack of pathognomonic laboratory tests for PEA, it is presentation (13,21). rarely diagnosed prior to imaging. With the increased MRI findings are very similar with CT and include an awareness of PEA and its imaging features, the oval-shaped fat intensity mass with a central dot on T1 numbers of incidental diagnoses during laparotomy are