Ultrasound diagnosis of diverticulitis

Abstract

Diverticular disease accounts for approximately 312 000 hospital admissions in the United States annually, and costs nearly 2.6 billion dollars.[1,2] Approximately 20% of Americans with diverticular disease will experience at least one episode of acute diverticulitis, necessitating a visit to their physician’s office or the emergency department (ED) for treatment.[3] As the risk of developing diverticulitis rises with age (nearly 50% of people aged over 60 years have colonic diverticula), the incidence is rising as the elderly population grows.[4] The majority of the patients are treated non-operatively, with a course of oral antibiotics and diet modification. Although computed tomography (CT) imaging is considered the “gold standard” for the diagnosis of acute diverticulitis in the United States, ultrasound is routinely used in Europe, Asia, and Africa as the initial imaging modality of choice in the evaluation of patients with suspected diverticulitis. Recent studies[5,6] have suggested that there is no significant difference in the test performance characteristics of CT as opposed to ultrasound for the diagnosis of diverticulitis. We present two cases in which point-of-care ultrasound was used to diagnose acute uncomplicated diverticulitis in the ED. Case 1 A 30-year-old man with no significant history of medication or surgery presented to the ED because of abdominal pain for several days. He stated that the pain began four days before presentation after breakfast at home, and subsequently deteriorated as a constant, non-radiating pressure. There were no alleviating or aggravating factors. The patient had no history of similar abdominal pain, nor nausea, vomiting, hematemesis, change in bowel habits, fever, anorexia, dysuria, testicular pain, back pain, or rash. On presentation, his temperature was 98.1 °F, heart rate 77 beats per minute, blood pressure 143/92 mmHg, respiratory rate 16 breaths per minute, and oxygen saturation 99% while breathing room air. The patient was alert and oriented and in no acute distress. His sclerae were anicteric. His abdomen was soft with mild tenderness in the left lower quadrant. No rebound or voluntary guarding was noted. There was no costovertebral angle (CVA) tenderness to palpation. In addition, there was no tenderness at McBurney’s point. His genital examination was normal. An emergency physician (EP) performed a point-of-care abdominal ultrasound, paying particular attention to the left lower quadrant of the abdomen. The sigmoid colon was identified in the left lower quadrant of the abdomen, with evidence of bowel wall thickening (Figure 1). In addition, a single diverticulum, visualized as an echo-poor protrusion from the colon wall with surrounding hyperechoic fat stranding, indicative of active inflammation, was noted at the point of maximal tenderness (Figure 2). The EP determined that the patient’s presentation combined with the point-of-care ultrasound images was consistent with a diagnosis of acute diverticulitis. The EP offered the patient the option of further testing with CT imaging versus empiric treatment with oral antibiotics. The patient opted to forego further radiologic testing and was subsequently discharged with a course of oral antibiotics and close primary care follow-up. Open in a separate window Figure 1 This figure demonstrates a measurement taken by the EP of the bowel wall that is approximately 1 cm. A measurement of >4–5 mm is indicative of bowel wall thickening.