A 67-year-old man presents to the emergency department with 2 days of worsening left lower quadrant abdominal pain and fever. His medical history is significant for hypertension and chronic constipation. Medications include lisinopril and hydrochlorothiazide. Temperature is 38.2°C (100.8°F), blood pressure is 132/80 mm Hg, pulse is 102/min, and respiratory rate is 18/min. Physical examination reveals focal left lower quadrant tenderness without rebound or guarding. Laboratory studies demonstrate a leukocyte count of 15,000/mm³.
Which of the following is the most appropriate next step in diagnosis?
The correct answer is:
B: CT scan of the abdomen and pelvis with contrast.
This patient has classic findings of acute diverticulitis, including fever, leukocytosis, and left lower quadrant abdominal pain. CT imaging is the preferred diagnostic study because it confirms the diagnosis and identifies complications such as abscesses, perforation, fistulas, or obstruction. The results help guide subsequent management decisions.
Answer choice A: Colonoscopy, is incorrect.
Colonoscopy is generally avoided during acute diverticulitis because insufflation may increase the risk of perforation. It is typically performed after recovery to confirm the presence of diverticulosis and exclude a malignancy masquerading as diverticulitis.
Answer choice C: Exploratory laparotomy, is incorrect.
Surgery may be necessary for perforation, generalized peritonitis, or failure to improve with medical management. This patient is hemodynamically stable and requires diagnostic imaging before invasive intervention.
Answer choice D: Fecal occult blood testing, is incorrect.
This test is useful in colorectal cancer screening but does not establish the diagnosis of diverticulitis.
Answer choice E: Upper endoscopy, is incorrect.
Upper endoscopy evaluates esophageal, gastric, and duodenal pathology and does not aid in the diagnosis of suspected diverticulitis.
Key Learning Point
CT imaging is the diagnostic test of choice for suspected acute diverticulitis and helps identify disease-related complications.
