Differentials
Diverticulitis
SIGNS / SYMPTOMS
Severe constipation; abdominal pain is more common and typically localizes to the left lower quadrant.
No pulsatile abdominal mass on clinical examination. Instead, abdominal or perirectal "fullness" may be appreciated. Fever is possible.[87]
INVESTIGATIONS
Stool guaiac testing may be trace positive.
Leukocytosis may be present.
CT scan will demonstrate a normal-caliber aorta and possibly diverticula, inflammation of the pericolic fat or other tissues, bowel-wall thickness >4 mm, or a peridiverticular abscess.[87]
Ureteric colic
SIGNS / SYMPTOMS
Severe abdominal pain that starts in the flank and radiates anteriorly to the groin.
Associated with nausea, emesis, hematuria, dysuria, and urinary frequency or urgency.[88]
Men >55 years of age presenting with ureteric colic should be considered to have a leaking/ruptured AAA until proven otherwise.
INVESTIGATIONS
Urinalysis positive for blood and may demonstrate crystals and/or evidence of infection.
Ultrasound and CT scan will demonstrate a normal-caliber aorta and possibly ureteral or renal stones.[88]
Irritable bowel syndrome (IBS)
SIGNS / SYMPTOMS
Intermittent abdominal discomfort with flares lasting 2 to 4 days.
Associated symptoms may include bloating, stool frequency, and abnormal defecation.
Women ages 20 to 40 years are affected more often than men.
General examination is usually normal, although some patients may appear anxious. There may be poorly localized abdominal tenderness to palpation.[89]
INVESTIGATIONS
Imaging modalities are often inconclusive, but will demonstrate a normal-caliber aorta.
Inflammatory bowel disease
SIGNS / SYMPTOMS
Abdominal pain is often "crampy" and left-sided. Patients typically have diarrhea (bloody and nonbloody), urgency of defecation, and tenesmus.
Extraintestinal manifestations are common in Crohn disease.
Abdominal examination may demonstrate abnormal bowel sounds, detection of an abdominal mass, and pain on palpation. Mucocutaneous lesions may be visible. Perianal fistulae, fissures, or abscesses may be present on rectal examination.[90]
INVESTIGATIONS
Anemia is common.
Ultrasound or CT scan will demonstrate a normal-caliber aorta.
Endoscopic evaluation with biopsy shows typical lesions of ulcerative colitis or Crohn disease.[90]
Appendicitis
SIGNS / SYMPTOMS
Pain is typically periumbilical with localization to the right lower quadrant.
Associated nausea, emesis, and anorexia are common.
Patients are classically febrile with tenderness in the right lower quadrant or rebound tenderness on abdominal examination.
INVESTIGATIONS
Leukocytosis and sterile pyuria on urinalysis is common.
Ultrasound or CT scan will demonstrate a normal-caliber aorta with an inflamed appendix or evidence of perforation.
Ovarian torsion
SIGNS / SYMPTOMS
Women have sudden, continuous, nonspecific pain in the lower abdomen; nausea and emesis are common. Patients may demonstrate fever on clinical exam, and an adnexal mass may be palpable.[91]
INVESTIGATIONS
Leukocytosis may be present. Ultrasound will demonstrate a normal-caliber aorta and possibly reduced or absent adnexal vascular flow.[91]
Gastrointestinal (GI) hemorrhage
SIGNS / SYMPTOMS
Patients presenting with hemorrhagic shock may mimic aortic rupture. A history of previous GI bleed, hematemesis, melena, or bright red blood per rectum is common.
Historical risk factors for GI malignancy or peptic ulcer disease may be elicited.
On rectal examination gross blood may be visible, or coffee ground hematemesis may be returned with nasogastric tube placement.
INVESTIGATIONS
Stool is likely to be guaiac positive.
Endoscopic evaluation may demonstrate the luminal bleeding source along with mucosal ulcerations, polyps, or tumor.
Ultrasound or CT scan will demonstrate a normal-caliber aorta.
Splanchnic artery aneurysms/acute occlusion
SIGNS / SYMPTOMS
Acute embolic or thrombotic occlusion of the splanchnic vessels may result in acute excruciating midabdominal pain with few early physical findings.
Patients typically have unremitting, intense midabdominal pain with nausea and vomiting that might be accompanied by explosive diarrhea.
Most splanchnic artery aneurysms are asymptomatic until rupture.[92]
INVESTIGATIONS
Leukocytosis, hemoconcentration, and systemic acidosis are common with acute splanchnic vessel occlusion. Elevated levels of serum amylase, inorganic phosphorus, creatinine phosphokinase, and alkaline phosphatase may accompany frank bowel infarction.
Angiography is diagnostic and potentially therapeutic in the case of vascular occlusion.
Ultrasound and CT scan will demonstrate a normal-caliber aorta and will diagnose any splanchnic artery aneurysms.[92]
Use of this content is subject to our disclaimer