Usefulness of CT Scan in Diagnosing Acute Appendicitis in Patients with Low Alvarado Scores.

Corresponding Author:
Khawaja Bilal Waheed,
King Fahad Military Medical Complex,
(KFMMC), P. O. Box 946,
Postal Coad 31932, Dhahran,
Saudi Arabia.
E-mail: khawaja@kfmmc.med.sa

ABSTRACT

BACKGROUND

Alvarado score has been routinely used in clinical practice for assessing the probability of acute appendicitis in patients presenting with right lower quadrant abdominal pain. Computed tomography can be used for equivocal or difficult cases. We wanted to evaluate role of computed tomography (CT) in patients with low or equivocal Alvarado scores.

METHODS

This is a retrospective, observational study conducted in the Department of Radiology at our Hospital in Dhahran from October 2017 to October 2018. 138 patients with equivocal Alvarado scores (AS, 4-6) and negative (non-conclusive or limited) ultrasounds, were retrospectively reviewed. Pregnant, postoperative (bowel surgery) cases and chronic appendicitis cases were excluded. Diagnosis of acute appendicitis on CT was based on a thickened or fluid dilated appendix (diameter > 6mm, wall enhancement) with at least one of the associated findings (like appendicolith, peri-appendiceal fat stranding, free fluid, extra-luminal air foci, caecal base thickening and mesenteric lymph nodes). Imaging findings were reviewed by two radiologists and consensus reporting was made. Findings on CT were categorized as AA (Acute Appendicitis), OD (Other Diagnosis) and NOR (Normal). Surgical candidates were confirmed on histopathology, while non-surgical cases were followed up on either imaging or clinical grounds. Chi-square test was used to determine association. The main outcome measure was diagnosis on CT and histopathology.

RESULTS

29.7% (41 patients) were found to have acute appendicitis on CT imaging. Majority of patients with AS of 5 were having OD, while most of AA cases were having AS of 6. All patients with AS of 4 were having normal CT scans.

CONCLUSIONS

Computed tomography helps to diagnose acute appendicitis or establish an alternate diagnosis in patients with equivocal Alvarado scores.

KEY WORDS

Computed Tomography, Alvarado Score, Acute Appendicitis