M2E Too! Mellick's Multimedia EduBlog

The M2E Too! Blog by Larry Mellick, MD, presents important clinical pearls using multimedia.

By its name, M2E Too! acknowledges that it is one of many emergency medicine blogs, but we hope this will serve as a creative commons for emergency physicians.

Wednesday, May 3, 2017

Appendagitis, a Rare Cause of Abdominal Pain

The differential list of potential causes of abdominal pain is pretty long. Like most differentials, though, it usually boils down to a handful of more common etiologies benign and serious. Potentially life- or organ-threatening conditions such as appendicitis, diverticulitis, or ovarian or testicular torsion simply cannot be misdiagnosed and usually aren't missed.

We frequently find ourselves walking into the patient's room at the end of an extensive and exhaustive workup and announcing the good news that the cause of the pain isn't one of these more serious causes. As emergency physicians working in an uncontrolled and tactical environment, we get used to reassuring patients that it isn't something serious even though we are unable to provide a definitive diagnosis.

If we admit it, deep down we share a little bit of the frustration expressed by our internist colleagues who by self-report experience a degree of psychic pain when stuck with a differential list instead of a definitive diagnosis for a patient's complaint. We may also find ourselves quietly avoiding our frustration with having exposed the patient to the CT scan's radiation or the expense of sequential tests such as a screening ultrasound only to find "enlarged lymph nodes," "a small amount of free fluid," or a few normal appearing ovarian cysts.

Epiploic appendagitis is one diagnosis, albeit rare, that allows the emergency physician to give the patient pretty much all-around good news. Making the diagnosis of this condition caused by a twisting or necrosis of the fat appendages hanging off the colon allows us to give the patient a definitive diagnosis and the good news that they have a condition that will not require admission or surgical intervention. In fact, the treatment for this condition is ibuprofen, rest, and time. Epiploic appendagitis can be responsible for an "acute abdomen" presentation, but the associated condition is self-limited and requires only pain and inflammation management. In fact, ibuprofen is frequently sufficient. The condition is rare enough that the few times that we've made the diagnosis before confirmation by CT scan were considered "high-five" moments. Most recently, the diagnosis was made in a 17-year-old boy sent to the emergency department because of suspicion for appendicitis. (See video​.)

What's the skinny on this condition that frequently causes your colleagues and the patient to correct your suspected mispronunciation of "appendicitis"?

-Epiploic appendagitis (EA) is frequently a condition unknown to clinicians. (AJR Am J Roentgenol 2009;193[5]:1243.)
-The term "epiploic appendagitis" is attributed to Lynn, et al., in 1956 who described a primary inflammatory disease of the fatty colonic appendages. (Surg Gynecol Obstet 1956;103[4]:423.)
-EA has other aliases such as appendicitis epiploica, hemorrhagic epiploitis, epiplopericolitis, or appendagitis. (Surg Gynecol Obstet 1956;103[4]:423.)
-EA is the result of ischemic infarction of an epiploic appendage following torsion or spontaneous thrombosis of the central draining vein.
-The epiploic appendages are finger-like projections of adipose tissue typically arranged in parallel rows along the colon. (Arch Surg 1985;120[10]:1167.)
-Numbering between 50 to 100, these appendages cover the entire adult colon but are larger and most abundant on the transverse and sigmoid colon.
-Epidemiologic studies suggest that the true incidence of EA is not known, but it has been reported in two percent to seven percent of patients initially suspected of having acute diverticulitis. (Nat Rev Gastroenterol Hepatol 2011;8[1]:45.)
-This condition usually occurs more commonly in men in the fourth and fifth decades of life, but also occurs in women and children.
-Sudden focal, nonmigrating lower abdominal pain and tenderness with a dull and colicky pain that waxes and wanes may be described by the patient. (Dig Dis Sci 2004;49[2]:347.)
-Ultrasound of EA has characteristic findings and MRI appears to be a reliable tool, but CT is the current imaging study of choice.
-Classically the findings of epiploic appendagitis on CT is a fat-density oval lesion called a “ring sign” consisting of a central fatty core (between 1.4 cm and 3.5 cm in length) surrounded by inflammation and located on the anterior aspect of the sigmoid colon. (Radiol 2005;237[1]:301; AJR Am J Roentgenol 2004;183[5]:1303.) A central dot corresponding to a thrombosed appendage vein is sometimes evident. (Radiology 1997;204[3]:713.)

When your colleagues try to correct your "mispronunciation" of appendicitis, your response should be, "Heck no, I meant to say appendagitis. Go look it up!"

Watch a video interview with a young patient with epiploic appendagitis.