Acute Appendicitis vs Acute Cholecystitis
Acute Appendicitis and Acute Cholecystitis are easy to mix up on the boards. Here's a side-by-side comparison — presentation, workup, imaging, and first-line treatment — drawn from our full outlines.
Acute Appendicitis vs Acute Cholecystitis at a glance
- Acute Appendicitis: Obstruction-driven inflammation of the appendix; classic periumbilical-to-RLQ pain with peritoneal signs.
- Acute Cholecystitis: Inflammation of the gallbladder, most often from a stone obstructing the cystic duct.
Keep comparing — start your free trial
You've used your 2 free previews. Create your free account to see the full Acute Appendicitis vs Acute Cholecystitis comparison — plus all 514 diagnosis outlines, 6,400+ board-style questions, and an AI tutor. Your 7-day free trial includes everything, no credit card required.
Side-by-side comparison
| Feature | Acute Appendicitis | Acute Cholecystitis |
|---|---|---|
| At a glance | Obstruction-driven inflammation of the appendix; classic periumbilical-to-RLQ pain with peritoneal signs. | Inflammation of the gallbladder, most often from a stone obstructing the cystic duct. |
| Classic presentation | Periumbilical pain → migration to RLQ + anorexia + nausea + low-grade fever + RLQ tenderness with peritoneal signs.; Periumbilical pain migrating to RLQ over 12-24 h (visceral → somatic); Anorexia (highly sensitive); Nausea and vomiting (after onset of pain — unlike gastroenteritis where vomiting precedes pain); Low-grade fever;… | Postprandial RUQ pain lasting >6 h with fever, leukocytosis, and positive Murphy sign.; Constant, severe RUQ or epigastric pain lasting >6 h (vs <6 h in biliary colic); Radiation to right shoulder or interscapular area; Nausea and vomiting; Fever and chills; Anorexia; RUQ tenderness with positive Murphy sign (inspiratory arrest on… |
| Workup / key labs | Clinical diagnosis supported by imaging. Histopathology confirms post-operatively.; CBC — mild to moderate leukocytosis (10-18,000) with left shift; very high WBC suggests perforation; BMP, CRP; Urinalysis — exclude UTI; mild pyuria/hematuria possible from inflamed appendix adjacent to ureter; Pregnancy test in women of childbearing age… | Tokyo Guidelines (TG18): (A) local signs — Murphy sign, RUQ mass/pain/tenderness; (B) systemic signs — fever, leukocytosis, elevated CRP; (C) imaging characteristic of cholecystitis. Definite diagnosis requires 1 from A + 1 from B + imaging.; CBC — leukocytosis with left shift; BMP; LFTs — mildly elevated AST/ALT and alk phos (~30%);… |
| Imaging | CT abdomen/pelvis with contrast — modality of choice in adults; sensitivity and specificity >95%; findings: dilated appendix >6 mm, wall thickening, periappendiceal fat stranding, fluid, abscess, fecalith; Ultrasound — first-line in children and pregnant women to avoid radiation; operator-dependent; MRI — alternative in pregnancy if… | RUQ ultrasound — first-line; findings: gallstones, gallbladder wall thickening >3 mm, pericholecystic fluid, sonographic Murphy sign, distended gallbladder; Hepatobiliary iminodiacetic acid (HIDA) scan — most sensitive/specific; non-visualization of gallbladder after 1-4 h confirms cystic duct obstruction; used when ultrasound… |
| First-line treatment | NPO, IV fluids, analgesia, antiemetics; IV antibiotics covering Gram-negative and anaerobic flora — piperacillin-tazobactam, ceftriaxone + metronidazole, or ertapenem; administer pre-operatively; Laparoscopic appendectomy — standard of care; lower wound infection rate and faster recovery vs open; Open appendectomy — alternative when… | NPO, IV fluids, analgesia (NSAIDs and opioids; morphine traditionally avoided over sphincter of Oddi concerns but clinically used); IV antibiotics — piperacillin-tazobactam, ceftriaxone + metronidazole, or ertapenem (broaden for severity); Early laparoscopic cholecystectomy — within 72 h preferred; equivalent outcomes to delayed… |
Drill Acute Appendicitis vs Acute Cholecystitis questions on FirstPassPA
Turn this comparison into retention. 6,400+ board-style questions with an AI tutor that explains every answer — free to start, no card required.
Start studying free → Try today's free questionEducational use only. This outline is a study aid for PA students and is not medical advice or a substitute for clinical judgment. FirstPassPA is an independent study tool and is not affiliated with, endorsed by, or sponsored by NCCPA or PAEA. PANCE® and PANRE® are registered trademarks of the National Commission on Certification of Physician Assistants; End of Rotation™ is a program of the Physician Assistant Education Association.