Labs
CBC
Chemistry
LFTs
Lipase
Urinalysis
Imaging
CT with IV and PO contrast (Sn 97%, Sp 100%)
Pericolic stranding
Bowel wall thickening
Wall enhancement (inner and outer high attenuation layers)
Perforation - extravasation of air/fluid
Abscess in 30% with fluid and/or gas
Bladder fistula
Ultrasound (Sn >90%)
Highly operator-dependent
Can identify diverticula, bowel wall thickening, inflammation, or abscess formation
MRI (Sn 98%, Sp 70-78%)
Difficult to obtain quickly in ED
CBC
Chemistry
LFTs
Lipase
Urinalysis
CT with IV and PO contrast (Sn 97%, Sp 100%)
Pericolic stranding
Bowel wall thickening
Wall enhancement (inner and outer high attenuation layers)
Perforation - extravasation of air/fluid
Abscess in 30% with fluid and/or gas
Bladder fistula
Ultrasound (Sn >90%)
Highly operator-dependent
Can identify diverticula, bowel wall thickening, inflammation, or abscess formation
MRI (Sn 98%, Sp 70-78%)
Difficult to obtain quickly in ED
Pericolic stranding
Bowel wall thickening
Wall enhancement (inner and outer high attenuation layers)
Perforation - extravasation of air/fluid
Abscess in 30% with fluid and/or gas
Bladder fistula
Highly operator-dependent
Can identify diverticula, bowel wall thickening, inflammation, or abscess formation
Difficult to obtain quickly in ED
Stable patient with history of confirmed<unk>  does not require further diagnostic evaluation
1st time episode or current episode different from previous requires diagnostic imaging
1st time episode or current episode different from previous requires diagnostic imaging
0	Mild clinical<unk> 
Ia	Confined pericolic inflammation or phlegmon
Ib	Pericolic or mesocolic abscess
II	Pelvic, distant intraabdominal, or retroperitoneal abscess
III	Generalized purulent peritonitis
IV	Generalized fecal peritonitis
Diverticulitis
Ischemic colitis
Kidney stone
Appendicitis
UTI
Appendicitis 
Pyelonephritis
Uvulitis