Method of predicting acute appendicitis
Embodiments of the invention provide method and devices for predicting the likelihood of acute appendicitis without invasive exploratory medical procedures. Several protein biomarkers: leucine-rich α-2-glycoprotein (LRG); S100-A8 (calgranulin); α-1-acid glycoprotein 1 (ORM); plasminogen (PLG); mannan-binding lectin serine protease 2 (MASP2); zinc-α-2-glycoprotein (AZGP1); Apolipoprotein D (ApoD); and α-1-antichymotrypsin (SERPINA3); are increased in the urine of patients with appendicitis. The method and devices comprise detecting the levels of these biomarkers and comparing with reference levels found in healthy individuals.
1. A method of treating a subject in need thereof comprising:
a. performing an assay to measure a level of a first acute appendicitis biomarker, leucine α-2 glycoprotein (LRG) in a urine sample obtained from the subject who exhibits at least one symptom of acute appendicitis; and
b. administering an appropriate treatment for acute appendicitis to the subject when the level of said LRG protein is greater than at least 2-fold over a reference level, wherein the reference level is a normalized level of the first acute appendicitis biomarker in a urine sample of a healthy human not having acute appendicitis, and wherein the patient is not administered a treatment for acute appendicitis when the level of said LRG is not greater than the reference level.
2. The method of claim 1 , further comprising determining the level of albumin in the urine sample from the subject.
3. The method of claim 1 , wherein the measuring is performed with an immunoassay.
4. The method of claim 2 , wherein the urine sample is obtained by depositing the urine on to a test strip.
5. The method of claim 1 , wherein the measuring is performed with a mass spectrometer.
6. The method of claim 1 further comprising measuring the level of at least one second acute appendicitis biomarker protein, wherein the second biomarker protein is selected from a group consisting of calgranulin A (S100-A8), α-1-acid glycoprotein 1 (ORM), plasminogen (PLG), mannan-binding lectin serine protease 2 (MASP2), Zinc-α-2-glycoprotein (AZGP1), α-1-antichymotrypsin (SERPINA3) and apolipoprotein D (ApoD), adipocyte specific adhesion molecule, AMBP, amyloid-like protein 2, angiotensin converting enzyme 2, BAZ1B, carbonic anhydrase 1, CD14, chromogranin A, FBLN7, FXR2, hemoglobin β, hemoglobin α, interleukin-1 receptor antagonist protein, inter-α-trypsin inhibitor, lipopolysaccharide binding protein, lymphatic vessel endothelial hyaluronan acid receptor 1, MLKL, nicastrin, novel protein (Accession No: IP100550644), PDZK1 interacting protein 1, PRIC285, prostaglandin-H2 D-isomerase, Rcl, S100-A9, serum amyloid A protein, SLC13A3, SLC2A1, SLC2A2, SLC4A1, SLC9A3, SORBS1, SPRX2, supervillin, TGFbeta2R, TTYH3, VA0D1, vascular adhesion molecule 1, versican, VIP36, α-1-acid glycoprotein 2, and β-1,3-galactosyltransferase; and
comparing the level of the at least one second appendicitis biomarker protein measured in the measuring step to a reference level for the measured at least one second appendicitis biomarker.
7. The method of claim 1 , wherein the normalization is performed against the level of albumin in the urine sample of a healthy human not having acute appendicitis.
8. The method of claim 2 , wherein the measuring is performed by the steps comprising:
a. contacting the urine sample from the human subject with the at least one antibody that specifically binds to LRG;
b. forming a complex between the at least one antibody and the LRG present in the urine sample;
c. adding a detection antibody that is labeled and is reactive to the at least one antibody in order to detect the complex;
d. washing to remove any unbound labeled detection antibody; and
e. converting the label to a detectable signal, wherein the detectable signal indicates the amount of appendicitis biomarker proteins present in the urine.