Related Experiment Video
Updated: Jan 20, 2026

Characterization of Glycoproteins with the Immunoglobulin Fold by X-Ray Crystallography and Biophysical Techniques
Published on: July 5, 2018
Value of CA-125 Glycoprotein in Predicting Acute Appendicitis; a Diagnostic Accuracy Study
Mahboub Pouraghaei1, Kavous Shahsavarinia1, Farzad Kakaei2
1Emergency Medicine Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Introduction:
Carcinogen antigen 125 (CA-125) is a glycoprotein antigen, which has shown potentials in predicting peritoneal inflammation. The aim of this study is to determine the value of CA-125 in predicting acute appendicitis (AA).
Methods:
This prospective diagnostic accuracy study was conducted on 15 - 70 year-old patients with acute abdominal pain, suspected to AA, referred to emergency department. The serum level of CA-125 was measured for all patients before appendectomy and its screening characteristics in detection of AA case (confirmed by histology findings) were calculated and reported with 95% confidence interval (CI).
Results:
95 patients with the mean age of 31.65 ± 12.9 (15-75) years were studied (54.3% male). Based on the histologic findings, 72 (75.8%) cases were categorized as AA (23 cases as severe). AA and non-AA (NAA) groups were similar regarding the mean age (p = 0.59), mean duration of symptoms (p = 0.08), mean white blood cell (WBC) count (p = 0.37), and mean PMN percentage (p = 0.55). Mean CA-125 level was 16.5 ± 20.0 U/mL in the AA group and 30.5 ± 6.1 U/mL in the NAA group (p = 0.001). Adjustment of analysis based on gender revealed a significant correlation between CA-125 level and diagnosis of AA only in females (34.23 ± 39 U/mL in NAA versus 20.7 ± 26.7 U/mL in AA, p = 0.012). The area under the ROC curve of CA-125 was 0.62 (95%CI: 0.51 to 0.72). Sensitivity, specificity, NPV, PPV, NLR, and PLR of CA-125 in 16.4 U/mL cut off (best point) were 77.8% (95%CI: 66.4 - 86.7), 50.0% (95%CI: 28.2 - 71.8), 83.6% (95%CI: 76.7 - 88.7), and 40.7% (95%CI: 27.4 - 55.6), 0.44 (95%CI 0.2 - 0.8), and 1.56 (95%CI: 1.0 - 2.4), respectively.
Conclusion:
Considering the lower levels of CA-125 in patients with AA compared with NAA cases and also weak screening performance characteristics, it seems that it could not be considered as an accurate screening tool in this regard.
Related Concept Videos
Appendicitis-II: Diagnostic Studies and Management
Diagnosing Appendicitis
It requires a multifaceted approach, starting with a detailed physical examination to pinpoint the location and nature of the pain and identify any associated symptoms. Laboratory tests play a crucial role. A complete Blood Count (CBC) typically reveals leukocytosis (an increased number of...
Acute Pyelonephritis II: Diagnostic Studies and Management
Acute Coronary Syndrome III: Diagnostic Studies
Acute Kidney Injury IV: Diagnostic Studies and Prevention
Appendicitis-I: Introduction
Etiology: Appendicitis can arise from various causes, primarily rooted in the obstruction of the appendix lumen. Factors contributing to this obstruction include fecal accumulation, lymphoid hyperplasia and, in...
Uncertainty in Measurement: Accuracy and Precision

