Appendicitis
Perforated appendicitis
Peritonitis
Abdominal aortic aneurysm
Crohn's disease (terminal ileitis)
Diverticulitis (cecal, Asian patients)
Ectopic
Endometriosis
Epiploic appendagitis
Herpes zoster
Inguinal hernia
Ischemic colitis
Kidney stone
Meckel's diverticulum
Mesenteric lymphadenitis
Mesenteric ischemia
Mittelschmerz
Neutropenic enterocolitis (typhlitis)<unk> 
Ovarian torsion
PID
Pyelonephritis
Psoas abscess
Testicular torsion
Perforated appendicitis
Diverticulitis
Kidney stone
UTI
Pyelonephritis
Ectopic pregnancy
Infectious colitis
Inflammatory bowel disease (Crohn's Disease, Ulcerative Colitis)
Inguinal hernia
Mesenteric ischemia
Epiploic appendagitis
Mittelschmerz<unk> 
Ovarian torsion
PID
Psoas abscess
Testicular torsion
Appendicitis
Abdominal aortic aneurysm
Herpes zoster
Endometriosis
Colon cancer
Irritable bowel syndrome
Small bowel obstruction
Ovarian cyst
Appendicitis
Tubo-ovarian abscess
Perforated appendicitis
Ovarian torsion
Peritonitis
Ectopic pregnancy
Abdominal aortic aneurysm