Algorithm: Diagnostic evaluation of suspected appendicitis

CT: computed tomography; MRI: magnetic resonance imaging.
* Experienced clinicians may use clinical judgment in place of the Alvarado score.
¶ Imaging available in <3 hours.
Δ Perform imaging if it becomes available during observation period.
◊ Intravenous contrast and, if available, low-radiation-dose image acquisition protocols recommended. If readily available, MRI can substitute for CT in women <30 years when gynecologic conditions are a diagnostic consideration.
§ Women of reproductive age should undergo laparoscopic exploration to look for other causes of abdominal pain. Appendectomy is performed at the time of laparoscopy. Most other patients can proceed with appendectomy directly without diagnostic laparoscopy.