The Clinical and Economic Correlates of Misdiagnosed Appendicitis

TLDR

Negative appendectomy is common but its clinical and financial consequences are underappreciated and vary across demographic groups. Using the 1997 Nationwide Inpatient Sample, the authors retrospectively identified patients who underwent appendectomy without an acute appendicitis diagnosis and analyzed age‑ and sex‑stratified rates, complications, case fatality, length of stay, and charges. Women, children under five, and adults over sixty had higher negative appendectomy rates, which were linked to longer stays, higher charges, higher case fatality, and more infectious complications, amounting to an estimated $741.5 million in hospital costs.

Abstract

Negative appendectomy (NA)--the nonincidental removal of a normal appendix--occurs commonly but the associated clinical- and system-level costs are not well studied.The frequency of adverse clinical outcomes and associated financial burden of hospitalizations during which NA is performed is greater than previously recognized and varies widely among demographic groups.Population-based, retrospective cohort study.The 1997 Nationwide Inpatient Sample of the Health Care Utilization Project.All surveyed patients assigned International Classification of Diseases, Ninth Revision procedure codes for appendectomy but without an associated diagnosis of acute appendicitis.The age- and sex-stratified rates of NA, the incidence of associated infectious complications and case fatality, and the average length of stay and hospitalization charges during those admissions.Nationwide, an estimated 261 134 patients underwent nonincidental appendectomies in 1997, and 39 901 (15.3%) were negative for appendicitis. Women had a higher rate of NA as did patients younger than 5 years and older than 60 years. When compared with patients with appendicitis, NA was associated with a significantly longer length of stay (5.8 vs 3.6 days, P<.001), total charge-admission ($18 780 vs $10 584, P<.001), case fatality rate (1.5% vs 0.2%, P<.001), and rate of infectious complications (2.6% vs 1.8%, P<.001). An estimated $741.5 million in total hospital charges resulted from admissions in which a NA was performed.There are significant clinical and financial costs incurred by patients undergoing NA during the treatment of presumed appendicitis. These should be considered when evaluating system-level interventions to improve the management of appendicitis.