CLINICAL QUESTION

What are the most accurate tests available in the primary care setting for diagnosing acute diverticulitis?

BOTTOM LINE

Point-of-care ultrasonography is increasingly finding a role at the bedside, and this study adds to that evidence base. In a patient with acute abdominal pain, point-of-care ultrasonography has been shown to be highly accurate for the diagnosis of appendicitis, small bowel obstruction, aneurysm, and now, acute diverticulitis. (Level of Evidence = 2a)

SYNOPSIS

The meta-analysis identified 15 prospective and two retrospective studies of the diagnosis of acute diverticulitis using signs, symptoms, and tests that are feasible in the primary care setting (none of the studies were done in the primary care setting). Only four studies reported data regarding signs and symptoms, and the two studies that evaluated the same sign or symptom had different sensitivity and specificity measures. Overall, the authors concluded that individual signs and symptoms are of uncertain value. A white blood cell count greater than 10 per μL (0.01 × 10⁹ per L) was not helpful (positive likelihood ratio [LR+] = 1.6; negative likelihood ratio [LR–] = 0.56). Three studies reported C-reactive protein (CRP) levels greater than 1.0 mg per dL (10 mg per L) and all reported excellent sensitivity (89% to 96%) but variable specificity. This means that a negative or normal CRP level is helpful for ruling out acute diverticulitis, but an abnormal value is not helpful (pooled sensitivity = 93%; 95% CI, 0.87 to 0.96; pooled LR– = 0.17; 95% CI, 0.05 to 0.43). The most accurate and best-studied test is ultrasonography (sensitivity 92%; specificity 94%; LR+ = 15.3; and LR– = 0.08). Point-of-care ultrasonography was as accurate as ultrasonography performed in the radiology department.