Biomarker of urinary 5-HIAA as a valuable predictor of acute appendicitis

BACKGROUND: Serotonin-containing cells are abundantly found in the appendix. Studies have shown that acute appendicitis is likely to be characterized by altered urinary 5-hydroxyindole acetic acid (5-HIAA), an active serotonin metabolite. The aim of this study is to investigate the diagnostic potential of 5-HIAA as a biomarker for acute appendicitis. METHOD: This cross-sectional study enrolled patients referred at the Madani Hospital, with right iliac fossa pain, suspected to having the acute appendicitis. Before the initiation of the basic treatment and surgery, urine samples were obtained from the patients. Enzyme-linked immunosorbent assay (ELISA) was used for the analysis of 5-HIAA urinary levels. The obtained data were statistically analyzed using SPSS v18. RESULTS: Of 129 patients included in the study with the mean age of 29 years, 62 (48.1%) were men and 67 (51.9%) were women. Appendectomy was performed in 96 patients, where 81 cases were that of acute appendicitis. The mean levels of 5-HIAA in acute appendicitis group and in the negative appendectomy group was not statistically significant. The sensitivity of the test was 54.3% based on 7.4 ​μmol/L as cut-off %-HIAA value. CONCLUSION: Our study reports that 5-HIAA urine concentration is not a reliable diagnostic marker for the diagnosis of acute appendicitis.