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A 27-year-old woman with no past medical history presents to the emergency room with 24 hours of abdominal pain. The day prior to presentation, she developed diffuse, vague abdominal discomfort. She lost her appetite and went to bed early secondary to malaise. The following morning, the pain worsened in intensity, became sharp, and localized to the right lower quadrant.
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The patient is afebrile, with normal vital signs. On examination, she is focally tender to palpation in the right lower quadrant with voluntary guarding. Palpation of the left lower quadrant reproduces pain on the right. Her lab work is unremarkable with the exception of a mild leukocytosis to 13.
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Acute appendicitis is one of the most common surgical diagnoses presenting to the emergency room. It occurs most frequently among patients between their teens and thirties, with a slight male predominance (1.4:1) and with the highest proportion of cases affecting patients aged 10 to 19 years.1,2 Prompt recognition is paramount to prevent appendiceal perforation; however, appendicitis in women, children, and the elderly may present with an atypical constellation of signs and symptoms that delays diagnosis.
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The appendix is a blind-ending pouch arising from the cecum at the point where the taenia coli converge. A true diverticulum, it contains all layers of the colonic wall. In appendicitis, a fecalith, tumor, or lymphocyte proliferation blocks the lumen, and the appendix distends with mucus. Distension compromises blood supply to the appendiceal wall, and stasis within the appendix allows for bacterial overgrowth. Bacteria then invade the compromised wall of the appendix, producing an inflammatory exudate that irritates the peritoneum. Local ischemia follows initial inflammation and progresses to perforation with the development of contained abscess, phlegmon, or generalized peritonitis.
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CLINICAL PRESENTATION
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The hallmark of appendicitis is abdominal pain that starts in the peri-umbilical region and is described as dull or cramping, followed by migration of discomfort to the right lower quadrant with a sharpening in quality. The peri-umbilical pain arises secondary to stimulation of visceral afferent nerve fibers at T8-T10 as intraluminal pressure increases. Pain becomes localized and sharp when inflammation extends to the serosa and irritates the parietal peritoneum. Other associated symptoms are nonspecific and may include anorexia, nausea, vomiting, diarrhea, and low-grade fever. Patients may complain of dysuria if the appendiceal tip assumes a pelvic location.
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On examination, the classic finding is tenderness at McBurney’s point, a location one-third along a line drawn from the anterior superior iliac spine to the umbilicus. However, this right lower quadrant tenderness may be subdued if the tip of the appendix is retrocecal, or if it dives into the pelvis. In these circumstances, other physical examination findings may aid diagnosis. A positive Rovsing’s sign, when palpation of the left lower quadrant reproduces abdominal pain ...