Appendicitis
From Medical-Wiki
One of the most common surgical conditions is appendicitis. Because it can imitate a great many other circumstances, it can defy easy diagnosis. While a variety of increasingly sophisticated diagnostic tools have been used, the rate of negative appendectomies remains the same.
Obstruction of the appendiceal lumen is the primary pathology involved in infection of the appendix. This leads to appendiceal distension, bacterial invasion, and in the worst cases, ruptures and spillage of pus into the peritoneal cavity.
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Morbidity & mortality
The mortality rate is estimated to be between 0.2% and 0.8% (from the disease and not from surgical intervention). However, mortality increases to above 20% in populations older than 70.
Differential diagnosis
A differential diagnosis includes pelvic inflammatory disease (PID), tubo-ovarian abscess, endometriosis, mesenteric adenitis, carcinoma of the colon, carcinoma of the appendix, diverticulitis, ureterolithiasis, diarrhea and infectious colitis, ovarian torsion, ovarian cysts, omental torsion, cholecystitis, and Crohn’s disease. Basically, if it’s in there, and it can have a problem, it’s part of the differential. [1]
Clinical course
The classic clinical course for appendicitis is of rather diffuse abdominal pain preceded by anorexia, increasing localization of pain to the RLQ, increasing toxicity, fever, and increasingly obvious signs of peritonitis.
However, the capacity of the omentum to surround an infected appendix, the rate at which the appendix becomes distended, the varying ability of patients to tolerate pain, and other comorbid intra-abdominal pathology impart variability to this “classic” presentation that can be truly baffling.
This has initiated a prolonged argument about how quality of care should be measured. One opinion is that quality corresponds to a low level of negative appendectomies—a condemnation of “trigger-happy surgeons.” The opposite philosophy stresses the goal of a low incidence of operations for appendiceal rupture—a condemnation of delaying surgical intervention long enough to expose patients to the mortality and morbidity of peritonitis.
Appendicitis in children
Children represent a particularly difficult population. Appendicitis is often delayed or missed in this population—for a variety of reasons. A 1998 study demonstrated the problems with delayed intervention, concluding,”... perforation rate increases with duration of symptoms and delayed presentation is therefore an important factor in determining perforation rate in acute appendicitis.” [2]
Types of surgical treatment
Another factor that has been introduced into the debate is the type of surgical intervention. With the advent of laparoscopic surgery, operative complication rates have decreased. A 2004 Cochrane Review suggested that laparoscopic surgery is superior to conventional surgery. [3]
This would theoretically increase the weight of risk versus benefit in the direction of early intervention. But the debate continues. Helical CT scans, touted as a technique that would drive negative appendectomies to zero, have not lowered their rate to any significant degree. [4]
Thus, management of suspected appendicitis continues to rely on clinical judgement. A guideline from the Scottish NHS suggests that UAs should be used to R/O UTI; pregnancy tests should be used to R/O ectopic pregnancies; abdominal x-rays are of little value; a normal WBC does not exclude appendicitis; ultrasound may be useful in the assessment of masses or abscesses but are of little value to the clinical diagnosis of appendicitis; and raised inflammatory markers, clinical signs of peritonitis, and pain migration (ironically, the old criteria) may be the best indicators of the disease. [5]
