Abstract: Appendicitis can be detected in human beings suspected of having appendicitis by determining a threshold level of 10 mg/liter of .sigma.-hydroxyhippuric acid in the urine of such humans. This threshold level can be determined by qualitative, semiquantitative, or quantitative methods including HPLC (high pressure liquid chromatography), TLC (thin layer chromatography), radioimmunoassay, colorimetric tests, NMR (nuclear magnetic resonance), mass spectrometry, electrophoresis, monoclonal antibody tests, and enzymatic tests. The absence of appendicitis can be established by the presence of .sigma.-hydroxyhippuric acid in concentrations less than about 10 mg/liter in a urine sample.

Abstract: Appendicitis can be detected by determining a threshold presence of the urinary pigment uroerythrin, in the urine of persons suspected of having appendicitis. The threshold presence of uroerythrin can be determined by precipitation of a sediment having a pink to red color. Additional qualitative, semiquantitative, or quantitative methods including HPLC (high pressure liquid chromatography), TLC (thin layer chromatography), radioimmunoassay, colorimetric tests, NMR (nuclear magnetic resonance), mass spectrometry, electrophoresis, monoclonal antibody tests, and other enzymatic tests may also be employed to measure uroerythrin levels.