Scientific paper
The use of abdominal computed tomography scan decreases the frequency of misdiagnosis in cases of suspected appendicitis

Presented at the 54th Annual Meeting of the Southwestern Surgical Congress, Coronado, California, April 7–10, 2002.
https://doi.org/10.1016/S0002-9610(02)01086-3Get rights and content

Abstract

Background:

Despite considerable experience the reported frequency of misdiagnosis in patients undergoing appendectomy continues in the range of 20% to 40% in some populations.

Methods

We developed a clinical guideline that recommended abdominal computed tomography (CT) for all nonpregnant adults in whom the diagnosis of appendicitis was suspected unless the diagnosis could be ruled out clinically. The records of adult patients that underwent appendectomy from July 1998 through October 2001 were reviewed. The clinical guideline was developed in July 2000.

Results

There were 194 appendectomies performed, 114 prior to the guideline and 80 after the development of the guideline. The rate of misdiagnosis decreased from 25% to 6% (P <0.05), the rate of CT use increased from 32% to 84% (P <0.05), and the perforation rate remained unchanged.

Conclusions:

These results support the effectiveness of a clinical guideline that encourage the use of abdominal CT in decreasing the frequency of misdiagnosis in cases of suspected appendicitis.

Section snippets

Patients and methods

We performed a retrospective chart review of 114 consecutive adult patients who had nonincidental appendectomy between July 1998 and June 2000. There were 36 women and 78 men with an age range of 17 to 67 years and an average age of 35 years. In July 2000 we introduced a clinical guideline that encourages the use of abdominal CT scan for all nonpregnant adults in whom the diagnosis of appendicitis was suspected unless either the diagnosis of appendicitis could be excluded based on history,

Results

There were 194 appendectomies performed, 114 were done prior to the guideline encouraging use of abdominal CT and 80 after the development of the clinical guideline (Table 1). In the preguideline period 36 (32%) patients had a preoperative CT scan of the abdomen. Twenty-eight (25%) patients in the preguideline period were found to have a normal appendix. The rate of misdiagnosis in women was 47%. In the postguideline period 67 (84%) of 80 patients had a preoperative CT scan. Only 5 patients

Comments

The study demonstrates that abdominal CT can be used to increase diagnostic accuracy in patients with suspected appendicitis in whom the diagnosis could not be ruled out based on history, physical examination, and laboratory data or in whom the diagnosis of appendicitis with evidence of peritonitis was not obvious. The utilization of abdominal CT in patients undergoing appendectomy increased from 32% to 84% (P <0.05). The frequency of misdiagnosis of appendicitis was reduced from 25% to 6% (P

References (15)

  • P.M. Rao et al.

    Plain abdominal radiography in clinically suspected appendicitisdiagnostic yield, resource use, and comparison with CT

    Am J Emerg Med

    (1999)
  • R.H. Fitz

    Perforating inflammation of the veriform appendix

    Trans Assoc Am Phys

    (1886)
  • J.B. Murphy

    Two thousand operations for appendicitis

    Am J Med Sci

    (1904)
  • C.M. McBurney

    Experience with early operative interference in cases of disease of the veriform appendix

    NY Med J

    (1889)
  • F.R. Lewis et al.

    Appendicitisa critical review of diagnosis and treatment in 1000 cases

    Arch Surg

    (1975)
  • D. Pickuth et al.

    Suspected acute appendicitisis ultrasonography or computed tomography the preferred imaging technique?

    Eur J Surg

    (2000)
  • J.M. Lane et al.

    Suspected acute appendicitisnonenhanced helical CT in 300 consecutive patients

    Radiology

    (1999)
There are more references available in the full text version of this article.

Cited by (0)

View full text