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Epiploic appendagitis: the emergency department presentation1
The Journal of Emergency Medicine, Vol. 22, No. 1, 9 –13, 2002 Copyright © 2002 Elsevier Science Inc. Printed in the USA. All rights reserved 0736-4679/02 $–see front matter
PII S0736-4679(02)00430-9
Original Contributions
EPIPLOIC APPENDAGITIS: THE EMERGENCY DEPARTMENT PRESENTATION Eric L. Legome,
MD,*
Austin L. Belton, MD,† Robert E. Murray, Robert A. Novelline, MD†
MD,*
Pat M. Rao,
MD,†
and
*Department of Emergency Medicine, Massachusetts General Hospital and Division of Emergency Medicine, Harvard Medical School; and †Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts Reprint Address: Eric L. Legome, MD, Department of Emergency Medicine, Massachusetts General Hospital, Emergency Medicine Residency Office, Founders 150, Boston, MA 02114
e Abstract—We performed a structured retrospective chart review to describe clinical characteristics of Emergency Department (ED) patients diagnosed by history, physical examination, and abdominal computed tomography (CT) scan with epiploic appendagitis (EA). EA is a disease caused by inflammation of the appendix epiploica, subserosal adipose tissue along the colon. It may mimic surgical causes of acute abdominal pain, but is treated conservatively with pain management. There were 19 patients diagnosed with EA, with follow-up performed on 85%. All had focal, nonmigratory symptoms. Common findings included left lower quadrant pain and guarding, and a normal temperature and white cell count. No patient required operation. This preliminary work characterizes some common clinical features of ED patients diagnosed with EA. As use of emergency CT scan for abdominal pain increases, clinicians will encounter this more often. These features should also prompt the clinician to consider CT scan in patients with similar signs and symptoms. Accurate diagnosis may avoid unnecessary surgery. © 2002 Elsevier Science Inc.
INTRODUCTION Acute abdominal pain is a common complaint of patients presenting to Emergency Departments (ED), accounting for approximately 5% of all visits (1,2). The most common diagnosis made in these patients is nonspecific abdominal pain or pain that has no clear origin. The numerous disease processes that may present with this complaint create a difficult dilemma for the clinician evaluating the patient with an acute abdomen. Two serious and common diseases presenting with lower abdominal pain are appendicitis and diverticulitis. Traditionally, these entities have been diagnosed clinically. With the advent of computed tomography (CT) and advancements in the use of oral and rectal contrast, diagnosis of these inflammatory diseases has become more accurate (3,4). This has led to more timely surgical treatment when appropriate and avoidance of surgery when unnecessary. Epiploic appendagitis (EA) has been identified as an unusual cause of acute abdominal pain that can mimic appendicitis and diverticulitis. Treatment, however, is generally symptomatic. The increasing use of emergency abdominal CT scan has aided in the diagnosis of EA and in the differentiation of this inflammatory disease from its similar counterparts that require antibiotics and, commonly, surgical management. Epiploic appendagitis has been described in the Emergency Medicine literature only through case reports
e Keywords— epiploic; appendagitis; abdominal; CT scan; emergency
This study has not been previously published. It has been presented in abstract form at the New England Regional SAEM Conference in April, 2001.
RECEIVED: 8 November 2000; FINAL ACCEPTED: 19 June 2001
SUBMISSION RECEIVED:
30 May 2001; 9
10
E. L. Legome
(5,6). This study describes the clinical characteristics of a cohort of ED patients diagnosed with EA by history, physical examination, and abdominal CT scan findings. It is a large study of EA in the ED and will hopefully aid in the accurate differentiation of this disorder from the other etiologies of acute abdominal pain.
MATERIALS AND METHODS This investigation was performed in an urban academic ED with approximately 65,000 annual visits. Attending emergency radiologists, experienced in helical CT, interpret all studies, usually within 12 h. All patients diagnosed with epiploic appendagitis, either at ED discharge or at final discharge if admitted to the hospital, were identified by a review of ED visit logs and radiology CT scan logs from January 1995–January 1999. The hospital institutional review board granted approval. Structured retrospective chart review for multiple variables was performed independently by two authors (ELL, REM). Data were collected on a prepared structured sheet and compiled in an electronic database. Dichotomous variables were marked as either absent or present. Continuous variables were recorded as stated in the medical records. If the variable was missing for a specific finding, it was coded as such and not included in the final analysis. Attending Emergency Physician (EP), senior ED resident, and senior ED surgical consultant (if present) notes were analyzed in that respective order. Disagreements between findings were uncommon, but the EP attending note was considered the gold standard. Correlation between chart reviewers (ELL, REM) for significant findings, e.g., anorexia, nausea, vomiting, local tenderness, site of tenderness, and rebound, was calculated and disagreements were re-reviewed for consensus. Correlation coefficients between chart reviewers for these important variables ranged from 0.60 to 1.00. All patients underwent evaluation with emergency abdominal CT scans. The tests were performed for the pre-test diagnosis of appendicitis (n ⫽ 4) 21%, diverticulitis (n ⫽ 10) 52%, history of pain (n ⫽ 2) 11%, renal stone (n ⫽ 2) 11%, and one for rule out abscess 5%. For colon contrast material, 3% diatrizoate meglumine-saline solution was inserted rectally through an IV line connected to a pediatric rectal tube by a Christmas tree adapter. The CT scans were performed on a GE helical scanner (GE Medical Systems, Milwaukee, WI) using 5 mm thick slices, a pitch of 1.5 and 5 mm image spacing. For some patients, the images were reformatted to 1 mm spacing for better resolution. Statistical analysis was performed on STATA 5.0 (Stata Corp, College Station, TX). The kappa statistic of interrater agreement was used.
Table 1. Clinical Symptoms Symptoms
% of Patients
95% CI
Anorexia Nausea Vomiting Sudden onset of pain RLQ pain LLQ pain LUQ pain Constipation Diarrhea
32 36 21 26 26 73 5 10 10
12% to 56% 16% to 61% 6% to 45% 9% to 56% 9% to 51% 48% to 90% 1% to 25% 1% to 33% 1% to 33%
RLQ, right lower quadrant. LLQ, left lower quadrant. LUQ, left upper quadrant.
RESULTS Nineteen patients were diagnosed with EA. Forty-seven percent were women (95% CI 24 –71%). The mean age was 37.8 years (SD 10.4), and the range was 26 – 63 years. Chart review revealed that documentation was available for important variables described below in a range between 14 to 19 charts of the 19 total patients. As stated, analysis was performed based only on numbers of patients in each category where documentation was available. All patients had focal, nonmigratory symptoms; none had documented diffuse, rectal, or suprapubic pain; they were clearly documented as absent in 50%, 10%, and 50%, respectively. Other symptoms included: sudden onset of pain 26% (95% CI, 9% to 52%), right lower quadrant pain 26% (95% CI, 9% to 51%), left lower quadrant pain 73% (95% CI, 48% to 90%), left upper quadrant pain 5% (95% CI ,1% to 25%), anorexia 32% (95% CI, 12% to 56%), nausea 36% (95% CI, 16% to 61%), and vomiting 21% (95% CI, 6% to 45%). (Table 1). Anorexia, nausea, or vomiting were clearly documented as absent in 50%, 50%, and 60% of patients, respectively. All patients had documented bowel sounds, focal tenderness, and a normal genitourinary examination. Constipation and diarrhea were each reported in 10% (95% CI, 1% to 33%). Objective fever (temperature ⱖ38.6° [100.4°F] was unusual, found in 15% (95% CI, 3% to 39%). Maximum temperature was 38.6° [101.5°F], range 36.2°–38.6°C (97.1–101.5°F). Clinical signs included: right lower quadrant tenderness described in 31% (95% CI, 13% to 56%), left lower quadrant tenderness in 73% (95% CI, 48% to 90%). Guarding was reported in 47% (95% CI, 28% to 75%). (Table 2) The average WBC was 9.3/mm3 (SD 2.02, range 6.2– 14.2). The average number of days from onset of symptoms to presentation was 1.8 (range 0 – 6). The CT scan findings diagnostic of epiploic appendagitis were para-colonic inflammation at the site of the clinical findings and, in many cases, the actual fat
Epiploic Appendagitis
11
Table 2. Clinical Signs Signs RLQ tenderness LLQ tenderness Guarding Fever ⱖ38°C (100.4°F)
% of Patients
95% CI
31 73 47 15
13% to 51% 48% to 90% 28% to 75% 3% to 39%
RLQ, right lower quadrant. LLQ, left lower quadrant.
density epiploic appendages surrounded by inflammation. None showed CT findings of diverticulitis, that is, bowel thickening, inflamed diverticulum, fluid collections, free air, or fascial thickening. A follow up CT scan was performed on four patients, between 1 and 4 months after initial presentation, which confirmed epiploic appendagitis by focal residual fibrosis consistent with scarring of the epiploic appendage. Clinical follow-up, either by telephone or review of medical records from follow up appointments, was able to be performed on 85% of patients. No patient required operative intervention. Seven were treated, at least initially, with antibiotics, 70% in the first 2 years of the study. Five were admitted as inpatients, although none was admitted after the first year of the study when the diagnosis became better appreciated in our institution. One had a recurrence of symptoms. A repeat CT scan showed a resolution of epiploic appendagitis without another cause for the pain.
DISCUSSION First described by Vesalius in 1543 and first recognized on CT scan in 1986, epiploic appendixes are finger-like projections of adipose tissue arranged in parallel rows along the colon. Although the average appendage is 3 cm long in the adult, rare epiploica have grown to 15 cm (3,7,8). Almost 100 appendages adorn the average colon extending from the cecum to the sigmoid. Each appendage is supplied by one or two small arteries from the colonic vasa recta and is drained by a single vein. Historically, this entity has been referred to as appendixes epiploica, hemorrhagic epiploitis, and epiplopericolitis. Acute disease processes of these appendages can include: spontaneous torsion and hemorrhagic infarct, calcification due to aseptic fat necrosis, primary or secondary inflammation, enlargement by lipomas or metastases, and incarceration in hernias. Epiploic appendagitis has been recently reported in the radiologic literature and in a few Emergency Medicine case reports (3,5,6). This study is based on a large sample of reported cases of EA in the ED and highlights that while uncommon, EA is an underappreciated cause
of disease in the differential diagnosis of the acute abdomen. Localized abdominal pain in the absence of severe illness is the sine que non of epiploic appendagitis. Patients generally appear well. The pain is typically focal. The charts in our study did not clearly define the quality of pain, however, its quality has been noted to be dull, sharp, crampy or colicky (5,6,9). Right lower quadrant pain and tenderness has been reported in 50 –55% of patients and in the left lower quadrant in 30% (6,9). Similarly, in our study sample, all patients had focal, nonmigratory symptoms, and 95% (18/19) localized this pain to the lower quadrants. Left lower quadrant pain and tenderness was noted in 73% and right lower quadrant pain and tenderness in 26% and 31% of the patients, respectively. In the single patient who noted left upper quadrant pain, a diagnosis of left sided pylonephritis was reported 1 week earlier. Acute onset of abdominal pain was rare in this population (26%), with the majority reporting a gradual onset of focal abdominal pain. The frequency of gradual onset, focal, lower abdominal pain, and tenderness in this population emphasizes the need to consider EA in the differential diagnosis of suspected appendicitis and diverticulitis, both of which often present with similar abdominal signs and symptoms. Nausea, vomiting, and anorexia are relatively less common symptoms of EA, and fever is variably present. Prior studies report that patients experience nausea and vomiting approximately one-quarter of the time (10,11,7). Similarly, in our patient population, nausea was reported in 36% and vomiting in 21% of our patients, although they were not mentioned in half of the patients and may be higher. The subjective or objective elevation of temperature has been reported, but objective fever greater than 38.0°C (100.4°F) was unusual in our population (15%) (10). This may reflect the relatively benign nature of this disease compared to its surgical counterparts. There are no pathognomonic diagnostic laboratory values in the evaluation of EA. The white blood count may be abnormal but is generally not markedly elevated. The average WBC from this sample was 9.3 ⫻ 103/mm3, which is consistent with prior studies (7,12). This too may reflect the lack of significant inflammation seen on CT scan and the benign nature and course of the disease. Given the paucity of specific signs or symptoms, epiploic appendagitis is a clinical diagnosis of exclusion. The most common preoperative diagnoses associated with epiploic appendagitis include appendicitis, diverticulitis, gallbladder disease, ruptured or hemorrhagic ovarian cyst, ovarian torsion, ectopic pregnancy, colon cancer, abscess, mesenteric adenitis, and duodenal ulcer disease (8,12). Since the first report of EA diagnosed by CT scan was
12
reported in 1986, this entity has become more common in the radiologic differential diagnosis of the acute abdomen. Normally, appendixes epiploica are generally not seen on CT scan unless surrounded by a sufficient amount of intraperitoneal fluid such as with ascites or hemoperitoneum. They typically have fat attenuation and resemble other adipose structures such as retroperitoneal fat unless they are inflamed (12). Epiploic appendagitis appears on CT scan as a 2 to 3 centimeter, oval-shaped, fat density (but higher in attenuation than normal fat), or paracolic mass with thickened peritoneal lining and surrounding fat stranding (Figure 1). CT scan findings of epiploic appendagitis can be differentiated from diverticulitis due to the lack of bowel wall thickening, inflamed diverticulum, colonic perforation of contrast or free air, and fascial thickening. Diverticulitis more commonly has peri-colonic rather than paracolonic inflammation (10). Ultrasound also has been used to diagnose epiploic appendagitis. Sonographically, an inflamed appendage appears as a noncompressible, solid, hyperechoic ovoid mass with a subtle hypoechoic rim located at the point of maximal tenderness (13). Prior to the advent of CT scanning, the diagnosis and treatment of epiploic appendagitis was surgical exploration with simple ligation of the inflamed appendage. The management of EA is changing as more sophisticated imaging modalities are utilized and preoperative diagnosis is established. Given the increasing frequency of abdominal CT scans being performed for abdominal pain, the recognition of EA has increased. In a retrospective study of 660 CT scans performed for suspected appendicitis or diverticulitis, 11 met criteria for EA and seven of these were misinterpreted (14). As radiologists and clinicians become more familiar with this disease, unnecessary surgery, overtreatment, and excessive resource use can be avoided (3). Nontoxic patients with a consistent clinical history and physical examination, combined with appropriate imaging technique, can be managed conservatively. Many authors suggest, and our data help confirm, that the disease is self limiting and can be managed expectantly with oral anti-inflammatory medication (11,13). (No patients in our sample required surgical intervention, although three patients were lost to follow up.) Potential complications such as torsed appendage, adherence to other viscera leading to obstruction, and abscess formation have been reported (10). Despite these potential complications, antibiotics do not appear to be routinely necessary. In-hospital observation units as well as close follow up from home are reasonable alternatives for providing optimal care for patients with EA. Limitations of this study include its small sample size and retrospective design. Despite the relatively small number of patients, 85% were able to be contacted. This
E. L. Legome
Figure 1. Magnified Abdominal CT scan performed with rectally instilled colon contrast. (A) CT Scan of left lower quadrant shows a triangular zone of inflammation (see arrows) anterior to the descending colon. (B) Slightly lower scan shows the actual fat density epiploic appendage (arrow) surrounded by fat stranding and inflammation.
study was conducted at a large, urban, academic center with formal radiology teaching in appendiceal CT interpretation. Many of the radiologists interpreting the CT scans are familiar with the research on EA and have published data in the radiologic literature. This may have
Epiploic Appendagitis
led to an increased capture of cases of EA over the study period. Furthermore, the gold standard used was the abdominal CT scan read by attending radiologists familiar with the diagnosis of EA and well trained in appendiceal CT scans. CONCLUSION This study describes certain clinical and laboratory variables in ED patients with epiploic appendagitis. Historical and physical examination factors in selected patients should prompt the clinician to consider the diagnosis of EA in nontoxic patients with abdominal pain and to perform a CT scan examination. The correct diagnosis can prevent unnecessary surgical intervention. Acknowledgments—We thank Sunday Clark, MPH, for assistance in statistical analysis.
REFERENCES 1. Brewer RJ, Golden GT, Hitch DC, et al. Abdominal pain analysis of 100 cases. Am J Surg 1976;131:219 –23.
13 2. Janzon L, Ryden CI, Zederfield B. Acute abdomen in the surgical emergency room. Acta Chir Scand. 1982;148:141. 3. Rao PM, Wittenberg J, Lawrason JN. Primary epiploic appendagitis: evolutionary changes in CT appearance. Radiology 1997;204: 713–7. 4. Rao PM, Rhea JT, Novelline RA, et al. Effect of computed tomography of the appendix on treatment of patients and the use of hospital resources. NEJM 1998;338:141– 6. 5. Legome EL, Sims C, Rao PM. Epiploic appendagitis. Adding to the differential diagnosis of acute abdominal pain. JEM 1999;17: 823– 6. 6. Vinson D. Epiploic appendagitis: A new diagnosis for the emergency physician. Two case reports and a review. JEM 1999;17: 827–32. 7. Fieber SS, Forman J. Appendices epiploicae: clinical and pathological considerations. Arch Surg 1953;66:329 –38. 8. Carmichael DH, Organ CH. Epiploic disorders: conditions of the epiploic appendages. Arch Surg 1985;120:1167–72. 9. Thomas JH, Rosoto FE, Patterson LT. Epiploic appendagitis. Surg Gynecol Obstet 1975;138:23–5. 10. Gharhremani GG, White EM, Hoff FL, et al. Appendices epiploicae of the colon: radiologic and pathologic features. Radiographics 1992;12:59 –77. 11. Desai HP, Tripodi J, Gold BM, Burakoff R. Infarction of an epiploic appendage: review of the literature. J Clin Gastroenterol 1993;16:323–5. 12. Mcgeer PL, McKenzie AD. Strangulation of the appendix epiploicae: a series of 11 cases. Canadian J Surg 1960;3:252–7. 13. Rioux M, Langis P. Primary epiploic appendagitis: clinical, US, and CT findings in 14 cases. Radiology 1994;191:523– 6. 14. Rao PM, Rhea JT, Wittenberg J, et al. Misdiagnosis of primary epiploic appendagitis. Am J Surg 1998;176:1–5.
PII S0736-4679(02)00430-9
Original Contributions
EPIPLOIC APPENDAGITIS: THE EMERGENCY DEPARTMENT PRESENTATION Eric L. Legome,
MD,*
Austin L. Belton, MD,† Robert E. Murray, Robert A. Novelline, MD†
MD,*
Pat M. Rao,
MD,†
and
*Department of Emergency Medicine, Massachusetts General Hospital and Division of Emergency Medicine, Harvard Medical School; and †Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts Reprint Address: Eric L. Legome, MD, Department of Emergency Medicine, Massachusetts General Hospital, Emergency Medicine Residency Office, Founders 150, Boston, MA 02114
e Abstract—We performed a structured retrospective chart review to describe clinical characteristics of Emergency Department (ED) patients diagnosed by history, physical examination, and abdominal computed tomography (CT) scan with epiploic appendagitis (EA). EA is a disease caused by inflammation of the appendix epiploica, subserosal adipose tissue along the colon. It may mimic surgical causes of acute abdominal pain, but is treated conservatively with pain management. There were 19 patients diagnosed with EA, with follow-up performed on 85%. All had focal, nonmigratory symptoms. Common findings included left lower quadrant pain and guarding, and a normal temperature and white cell count. No patient required operation. This preliminary work characterizes some common clinical features of ED patients diagnosed with EA. As use of emergency CT scan for abdominal pain increases, clinicians will encounter this more often. These features should also prompt the clinician to consider CT scan in patients with similar signs and symptoms. Accurate diagnosis may avoid unnecessary surgery. © 2002 Elsevier Science Inc.
INTRODUCTION Acute abdominal pain is a common complaint of patients presenting to Emergency Departments (ED), accounting for approximately 5% of all visits (1,2). The most common diagnosis made in these patients is nonspecific abdominal pain or pain that has no clear origin. The numerous disease processes that may present with this complaint create a difficult dilemma for the clinician evaluating the patient with an acute abdomen. Two serious and common diseases presenting with lower abdominal pain are appendicitis and diverticulitis. Traditionally, these entities have been diagnosed clinically. With the advent of computed tomography (CT) and advancements in the use of oral and rectal contrast, diagnosis of these inflammatory diseases has become more accurate (3,4). This has led to more timely surgical treatment when appropriate and avoidance of surgery when unnecessary. Epiploic appendagitis (EA) has been identified as an unusual cause of acute abdominal pain that can mimic appendicitis and diverticulitis. Treatment, however, is generally symptomatic. The increasing use of emergency abdominal CT scan has aided in the diagnosis of EA and in the differentiation of this inflammatory disease from its similar counterparts that require antibiotics and, commonly, surgical management. Epiploic appendagitis has been described in the Emergency Medicine literature only through case reports
e Keywords— epiploic; appendagitis; abdominal; CT scan; emergency
This study has not been previously published. It has been presented in abstract form at the New England Regional SAEM Conference in April, 2001.
RECEIVED: 8 November 2000; FINAL ACCEPTED: 19 June 2001
SUBMISSION RECEIVED:
30 May 2001; 9
10
E. L. Legome
(5,6). This study describes the clinical characteristics of a cohort of ED patients diagnosed with EA by history, physical examination, and abdominal CT scan findings. It is a large study of EA in the ED and will hopefully aid in the accurate differentiation of this disorder from the other etiologies of acute abdominal pain.
MATERIALS AND METHODS This investigation was performed in an urban academic ED with approximately 65,000 annual visits. Attending emergency radiologists, experienced in helical CT, interpret all studies, usually within 12 h. All patients diagnosed with epiploic appendagitis, either at ED discharge or at final discharge if admitted to the hospital, were identified by a review of ED visit logs and radiology CT scan logs from January 1995–January 1999. The hospital institutional review board granted approval. Structured retrospective chart review for multiple variables was performed independently by two authors (ELL, REM). Data were collected on a prepared structured sheet and compiled in an electronic database. Dichotomous variables were marked as either absent or present. Continuous variables were recorded as stated in the medical records. If the variable was missing for a specific finding, it was coded as such and not included in the final analysis. Attending Emergency Physician (EP), senior ED resident, and senior ED surgical consultant (if present) notes were analyzed in that respective order. Disagreements between findings were uncommon, but the EP attending note was considered the gold standard. Correlation between chart reviewers (ELL, REM) for significant findings, e.g., anorexia, nausea, vomiting, local tenderness, site of tenderness, and rebound, was calculated and disagreements were re-reviewed for consensus. Correlation coefficients between chart reviewers for these important variables ranged from 0.60 to 1.00. All patients underwent evaluation with emergency abdominal CT scans. The tests were performed for the pre-test diagnosis of appendicitis (n ⫽ 4) 21%, diverticulitis (n ⫽ 10) 52%, history of pain (n ⫽ 2) 11%, renal stone (n ⫽ 2) 11%, and one for rule out abscess 5%. For colon contrast material, 3% diatrizoate meglumine-saline solution was inserted rectally through an IV line connected to a pediatric rectal tube by a Christmas tree adapter. The CT scans were performed on a GE helical scanner (GE Medical Systems, Milwaukee, WI) using 5 mm thick slices, a pitch of 1.5 and 5 mm image spacing. For some patients, the images were reformatted to 1 mm spacing for better resolution. Statistical analysis was performed on STATA 5.0 (Stata Corp, College Station, TX). The kappa statistic of interrater agreement was used.
Table 1. Clinical Symptoms Symptoms
% of Patients
95% CI
Anorexia Nausea Vomiting Sudden onset of pain RLQ pain LLQ pain LUQ pain Constipation Diarrhea
32 36 21 26 26 73 5 10 10
12% to 56% 16% to 61% 6% to 45% 9% to 56% 9% to 51% 48% to 90% 1% to 25% 1% to 33% 1% to 33%
RLQ, right lower quadrant. LLQ, left lower quadrant. LUQ, left upper quadrant.
RESULTS Nineteen patients were diagnosed with EA. Forty-seven percent were women (95% CI 24 –71%). The mean age was 37.8 years (SD 10.4), and the range was 26 – 63 years. Chart review revealed that documentation was available for important variables described below in a range between 14 to 19 charts of the 19 total patients. As stated, analysis was performed based only on numbers of patients in each category where documentation was available. All patients had focal, nonmigratory symptoms; none had documented diffuse, rectal, or suprapubic pain; they were clearly documented as absent in 50%, 10%, and 50%, respectively. Other symptoms included: sudden onset of pain 26% (95% CI, 9% to 52%), right lower quadrant pain 26% (95% CI, 9% to 51%), left lower quadrant pain 73% (95% CI, 48% to 90%), left upper quadrant pain 5% (95% CI ,1% to 25%), anorexia 32% (95% CI, 12% to 56%), nausea 36% (95% CI, 16% to 61%), and vomiting 21% (95% CI, 6% to 45%). (Table 1). Anorexia, nausea, or vomiting were clearly documented as absent in 50%, 50%, and 60% of patients, respectively. All patients had documented bowel sounds, focal tenderness, and a normal genitourinary examination. Constipation and diarrhea were each reported in 10% (95% CI, 1% to 33%). Objective fever (temperature ⱖ38.6° [100.4°F] was unusual, found in 15% (95% CI, 3% to 39%). Maximum temperature was 38.6° [101.5°F], range 36.2°–38.6°C (97.1–101.5°F). Clinical signs included: right lower quadrant tenderness described in 31% (95% CI, 13% to 56%), left lower quadrant tenderness in 73% (95% CI, 48% to 90%). Guarding was reported in 47% (95% CI, 28% to 75%). (Table 2) The average WBC was 9.3/mm3 (SD 2.02, range 6.2– 14.2). The average number of days from onset of symptoms to presentation was 1.8 (range 0 – 6). The CT scan findings diagnostic of epiploic appendagitis were para-colonic inflammation at the site of the clinical findings and, in many cases, the actual fat
Epiploic Appendagitis
11
Table 2. Clinical Signs Signs RLQ tenderness LLQ tenderness Guarding Fever ⱖ38°C (100.4°F)
% of Patients
95% CI
31 73 47 15
13% to 51% 48% to 90% 28% to 75% 3% to 39%
RLQ, right lower quadrant. LLQ, left lower quadrant.
density epiploic appendages surrounded by inflammation. None showed CT findings of diverticulitis, that is, bowel thickening, inflamed diverticulum, fluid collections, free air, or fascial thickening. A follow up CT scan was performed on four patients, between 1 and 4 months after initial presentation, which confirmed epiploic appendagitis by focal residual fibrosis consistent with scarring of the epiploic appendage. Clinical follow-up, either by telephone or review of medical records from follow up appointments, was able to be performed on 85% of patients. No patient required operative intervention. Seven were treated, at least initially, with antibiotics, 70% in the first 2 years of the study. Five were admitted as inpatients, although none was admitted after the first year of the study when the diagnosis became better appreciated in our institution. One had a recurrence of symptoms. A repeat CT scan showed a resolution of epiploic appendagitis without another cause for the pain.
DISCUSSION First described by Vesalius in 1543 and first recognized on CT scan in 1986, epiploic appendixes are finger-like projections of adipose tissue arranged in parallel rows along the colon. Although the average appendage is 3 cm long in the adult, rare epiploica have grown to 15 cm (3,7,8). Almost 100 appendages adorn the average colon extending from the cecum to the sigmoid. Each appendage is supplied by one or two small arteries from the colonic vasa recta and is drained by a single vein. Historically, this entity has been referred to as appendixes epiploica, hemorrhagic epiploitis, and epiplopericolitis. Acute disease processes of these appendages can include: spontaneous torsion and hemorrhagic infarct, calcification due to aseptic fat necrosis, primary or secondary inflammation, enlargement by lipomas or metastases, and incarceration in hernias. Epiploic appendagitis has been recently reported in the radiologic literature and in a few Emergency Medicine case reports (3,5,6). This study is based on a large sample of reported cases of EA in the ED and highlights that while uncommon, EA is an underappreciated cause
of disease in the differential diagnosis of the acute abdomen. Localized abdominal pain in the absence of severe illness is the sine que non of epiploic appendagitis. Patients generally appear well. The pain is typically focal. The charts in our study did not clearly define the quality of pain, however, its quality has been noted to be dull, sharp, crampy or colicky (5,6,9). Right lower quadrant pain and tenderness has been reported in 50 –55% of patients and in the left lower quadrant in 30% (6,9). Similarly, in our study sample, all patients had focal, nonmigratory symptoms, and 95% (18/19) localized this pain to the lower quadrants. Left lower quadrant pain and tenderness was noted in 73% and right lower quadrant pain and tenderness in 26% and 31% of the patients, respectively. In the single patient who noted left upper quadrant pain, a diagnosis of left sided pylonephritis was reported 1 week earlier. Acute onset of abdominal pain was rare in this population (26%), with the majority reporting a gradual onset of focal abdominal pain. The frequency of gradual onset, focal, lower abdominal pain, and tenderness in this population emphasizes the need to consider EA in the differential diagnosis of suspected appendicitis and diverticulitis, both of which often present with similar abdominal signs and symptoms. Nausea, vomiting, and anorexia are relatively less common symptoms of EA, and fever is variably present. Prior studies report that patients experience nausea and vomiting approximately one-quarter of the time (10,11,7). Similarly, in our patient population, nausea was reported in 36% and vomiting in 21% of our patients, although they were not mentioned in half of the patients and may be higher. The subjective or objective elevation of temperature has been reported, but objective fever greater than 38.0°C (100.4°F) was unusual in our population (15%) (10). This may reflect the relatively benign nature of this disease compared to its surgical counterparts. There are no pathognomonic diagnostic laboratory values in the evaluation of EA. The white blood count may be abnormal but is generally not markedly elevated. The average WBC from this sample was 9.3 ⫻ 103/mm3, which is consistent with prior studies (7,12). This too may reflect the lack of significant inflammation seen on CT scan and the benign nature and course of the disease. Given the paucity of specific signs or symptoms, epiploic appendagitis is a clinical diagnosis of exclusion. The most common preoperative diagnoses associated with epiploic appendagitis include appendicitis, diverticulitis, gallbladder disease, ruptured or hemorrhagic ovarian cyst, ovarian torsion, ectopic pregnancy, colon cancer, abscess, mesenteric adenitis, and duodenal ulcer disease (8,12). Since the first report of EA diagnosed by CT scan was
12
reported in 1986, this entity has become more common in the radiologic differential diagnosis of the acute abdomen. Normally, appendixes epiploica are generally not seen on CT scan unless surrounded by a sufficient amount of intraperitoneal fluid such as with ascites or hemoperitoneum. They typically have fat attenuation and resemble other adipose structures such as retroperitoneal fat unless they are inflamed (12). Epiploic appendagitis appears on CT scan as a 2 to 3 centimeter, oval-shaped, fat density (but higher in attenuation than normal fat), or paracolic mass with thickened peritoneal lining and surrounding fat stranding (Figure 1). CT scan findings of epiploic appendagitis can be differentiated from diverticulitis due to the lack of bowel wall thickening, inflamed diverticulum, colonic perforation of contrast or free air, and fascial thickening. Diverticulitis more commonly has peri-colonic rather than paracolonic inflammation (10). Ultrasound also has been used to diagnose epiploic appendagitis. Sonographically, an inflamed appendage appears as a noncompressible, solid, hyperechoic ovoid mass with a subtle hypoechoic rim located at the point of maximal tenderness (13). Prior to the advent of CT scanning, the diagnosis and treatment of epiploic appendagitis was surgical exploration with simple ligation of the inflamed appendage. The management of EA is changing as more sophisticated imaging modalities are utilized and preoperative diagnosis is established. Given the increasing frequency of abdominal CT scans being performed for abdominal pain, the recognition of EA has increased. In a retrospective study of 660 CT scans performed for suspected appendicitis or diverticulitis, 11 met criteria for EA and seven of these were misinterpreted (14). As radiologists and clinicians become more familiar with this disease, unnecessary surgery, overtreatment, and excessive resource use can be avoided (3). Nontoxic patients with a consistent clinical history and physical examination, combined with appropriate imaging technique, can be managed conservatively. Many authors suggest, and our data help confirm, that the disease is self limiting and can be managed expectantly with oral anti-inflammatory medication (11,13). (No patients in our sample required surgical intervention, although three patients were lost to follow up.) Potential complications such as torsed appendage, adherence to other viscera leading to obstruction, and abscess formation have been reported (10). Despite these potential complications, antibiotics do not appear to be routinely necessary. In-hospital observation units as well as close follow up from home are reasonable alternatives for providing optimal care for patients with EA. Limitations of this study include its small sample size and retrospective design. Despite the relatively small number of patients, 85% were able to be contacted. This
E. L. Legome
Figure 1. Magnified Abdominal CT scan performed with rectally instilled colon contrast. (A) CT Scan of left lower quadrant shows a triangular zone of inflammation (see arrows) anterior to the descending colon. (B) Slightly lower scan shows the actual fat density epiploic appendage (arrow) surrounded by fat stranding and inflammation.
study was conducted at a large, urban, academic center with formal radiology teaching in appendiceal CT interpretation. Many of the radiologists interpreting the CT scans are familiar with the research on EA and have published data in the radiologic literature. This may have
Epiploic Appendagitis
led to an increased capture of cases of EA over the study period. Furthermore, the gold standard used was the abdominal CT scan read by attending radiologists familiar with the diagnosis of EA and well trained in appendiceal CT scans. CONCLUSION This study describes certain clinical and laboratory variables in ED patients with epiploic appendagitis. Historical and physical examination factors in selected patients should prompt the clinician to consider the diagnosis of EA in nontoxic patients with abdominal pain and to perform a CT scan examination. The correct diagnosis can prevent unnecessary surgical intervention. Acknowledgments—We thank Sunday Clark, MPH, for assistance in statistical analysis.
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13 2. Janzon L, Ryden CI, Zederfield B. Acute abdomen in the surgical emergency room. Acta Chir Scand. 1982;148:141. 3. Rao PM, Wittenberg J, Lawrason JN. Primary epiploic appendagitis: evolutionary changes in CT appearance. Radiology 1997;204: 713–7. 4. Rao PM, Rhea JT, Novelline RA, et al. Effect of computed tomography of the appendix on treatment of patients and the use of hospital resources. NEJM 1998;338:141– 6. 5. Legome EL, Sims C, Rao PM. Epiploic appendagitis. Adding to the differential diagnosis of acute abdominal pain. JEM 1999;17: 823– 6. 6. Vinson D. Epiploic appendagitis: A new diagnosis for the emergency physician. Two case reports and a review. JEM 1999;17: 827–32. 7. Fieber SS, Forman J. Appendices epiploicae: clinical and pathological considerations. Arch Surg 1953;66:329 –38. 8. Carmichael DH, Organ CH. Epiploic disorders: conditions of the epiploic appendages. Arch Surg 1985;120:1167–72. 9. Thomas JH, Rosoto FE, Patterson LT. Epiploic appendagitis. Surg Gynecol Obstet 1975;138:23–5. 10. Gharhremani GG, White EM, Hoff FL, et al. Appendices epiploicae of the colon: radiologic and pathologic features. Radiographics 1992;12:59 –77. 11. Desai HP, Tripodi J, Gold BM, Burakoff R. Infarction of an epiploic appendage: review of the literature. J Clin Gastroenterol 1993;16:323–5. 12. Mcgeer PL, McKenzie AD. Strangulation of the appendix epiploicae: a series of 11 cases. Canadian J Surg 1960;3:252–7. 13. Rioux M, Langis P. Primary epiploic appendagitis: clinical, US, and CT findings in 14 cases. Radiology 1994;191:523– 6. 14. Rao PM, Rhea JT, Wittenberg J, et al. Misdiagnosis of primary epiploic appendagitis. Am J Surg 1998;176:1–5.