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A 32-year-old man is brought to the emergency department due to severe abdominal pain, fever, nausea, and vomiting. The patient states that the pain started near the umbilicus yesterday evening, but has since moved towards the lower right side. He also reports that the pain increased in severity overnight, rating it up to a 10 on a 10-point scale. However, he now feels that the pain has diminished slightly. He describes the pain as sharp and states that it was especially bad en route to the hospital when the ambulance drove over bumps in the road. The patient has no past medical history and consumes a vegan diet. His temperature is 39.3°C (102.7°F), pulse is 124/min, respirations are 24/min, and blood pressure is 86/60 mmHg. Abdominal examination shows tenderness over the right lower quadrant. The patient is noted to tighten his abdominal muscles to lessen the pain. Which of the following physical examination signs is most likely to be present in this patient?  

External References

First Aid








Appendicitis p. 392

mittelschmerz vs p. 655

Ectopic pregnancy p. NaN

appendicitis differential diagnosis p. 392


with appendicitis p. 392


appendicitis p. 392

Pseudoappendicitis p. 142


Content Reviewers

The appendix is the little one-ended tube that’s attached to the cecum of the large intestine, sometimes it’s called the vermiform appendix, where vermiform means “worm-shaped”, so, that should paint a pretty clear picture of what it looks like.

This odd, yet kinda cute little worm-like structure’s function is actually unknown, though some theories suggest it might be a “safe-house” for the gut flora, and some evidence seems to suggests it plays a part in the lymphatic and immune system; other, arguably more cynical viewpoints maintain that it’s just a useless vestigial organ from our ancestors.

Whatever the case, the fact remains, it’s pretty talented at getting inflamed and causing abdominal pain, a condition known as appendicitis, as much as 10% of the population develops appendicitis, and it’s the most common surgical emergency of the abdomen.

Since the appendix is a hollow tube, the most common cause of inflammation is something getting stuck in or obstructing that tube, like a fecalith, a hardened lump of fecal matter that finds its way into the the lumen of the appendix and wedges itself there.

It could also be other things though, like seeds that weren’t digested, or even pinworm infections, which are intestinal parasites.

Another cause of obstruction, especially in children and adolescents, is lymphoid follicle growth, also known as lymphoid hyperplasia.

Lymphoid follicles are dense collections of lymphocytes that get to their maximum size in the appendix during adolescence. Sometimes this growth can literally obstruct the tube.

Also, when exposed to viral infections like adenovirus, measles, or even after immunizations, the immune system ramps up and these follicles can grow as well.


  1. "Robbins Basic Pathology" Elsevier (2017)
  2. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  3. "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
  4. "CURRENT Medical Diagnosis and Treatment 2020" McGraw-Hill Education / Medical (2019)
  5. "Effectiveness of a Staged US and CT Protocol for the Diagnosis of Pediatric Appendicitis: Reducing Radiation Exposure in the Age of ALARA" Radiology (2011)
  6. "APPENDICITIS" Emergency Medicine Clinics of North America (1996)

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