Appendicitis is often missed because physicians don’t think of it

“Diagnostic algorithms tend not to be very helpful for appendicitis because the clinical signs and tests are so variable. By keeping in mind common cognitive errors, unusual presentations, and the predictive value of tests, a physician may recognize an atypical case of appendicitis that would otherwise be missed . . .

. . . The freezing effect occurs when a physician latches onto a positive finding and loses sight of the bigger picture. This occurred in the case of a 29-year-old woman who came in with right lower quadrant pain and a temperature. She had a normal pelvic exam, but an ultrasound showed an ovarian cyst. She was sent home with a diagnosis of an ovarian cyst, and later came back with a ruptured appendix. Just because a diagnostic test is positive doesn’t mean it has pinpointed the cause of the patient’s complaint, he cautioned.

The availability error means judging a case too quickly based on how readily a diagnosis comes to mind. Dr. Rose offered the example of a 55-year-old woman who came in with gastric pain and vomiting. Her belly exam was normal, and family members had just had stomach flu. She was diagnosed with viral gastroenteritis, despite not having any diarrhea. Hers turned out to be an atypical presentation of a myocardial infarction.”

In this day and age, one has to rule out diseases that can kill the patient first, and then work down to less serious diseases. The days where one can diagnose clinically alone are gone. It will be atypical presentations of serious diseases that will get you.

For someone with right lower quadrant pain, the diseases that you don’t want to miss are appendicitis, pelvic inflammatory disease (in females), or bowel perforation. Hanging your hat on an ovarian cyst without adequately ruling out the diseases above (especially appendicitis), or excluding appendicitis based on a normal WBC, is inviting trouble.

Bottom line: Practive defensively, CT everyone, and keep yourself out of trouble.