Appendicitis

Overview


Plain-Language Overview

Appendicitis is an inflammation of the appendix, a small pouch attached to the large intestine. It affects the digestive system and can cause severe abdominal pain, usually starting around the belly button and then moving to the lower right side. Other common symptoms include nausea, vomiting, and sometimes fever. If untreated, the appendix can burst, leading to serious infections in the abdomen. This condition often requires urgent medical attention to prevent complications.

Clinical Definition

Appendicitis is the acute inflammation of the vermiform appendix, typically caused by obstruction of the appendiceal lumen by fecaliths, lymphoid hyperplasia, or less commonly tumors. This obstruction leads to increased intraluminal pressure, bacterial overgrowth, ischemia, and subsequent inflammation. The condition is a common cause of acute abdominal pain and a surgical emergency due to the risk of perforation and peritonitis. Clinically, it presents with right lower quadrant pain, anorexia, nausea, and fever. The pathophysiology involves a progression from mucosal inflammation to transmural necrosis if untreated. Early diagnosis and management are critical to prevent morbidity and mortality.

Clinical Presentation


Diagnostic Workup


Pathophysiology


Treatments


Prevention


Outcome & Complications


Differential Diagnoses


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