title: A novel sol particle immunoassay for fecal calprotectin in inflammatory bowel disease patients.
abstract: BACKGROUND
  We introduce a new assay method to measure the concentration of fecal calprotectin that can be applied in exclusive analyzers. The assay method uses gold colloidal reagents. In addition, we report performance evaluation results for the new method and the results of comparisons with enzyme-linked immunosorbent assay (ELISA) methods.
  
  
  METHODS
  We evaluated the new method by linearity tests and within-run tests. In addition, we collected specimens from patients with a definitive diagnosis of inflammatory bowel disease (n=566) and examined them using the new method. The results were compared with those from 2 commercially available ELISA kits.
  
  
  RESULTS
  In the linearity tests, the correlation coefficients between the measured values and the theoretical values were 0.9980-0.9990. In the within-run tests, the CVs were 3.4-4.3%. The correlation coefficients for our method and the 2 ELISA kits showed high correlations of 0.945 and 0.942.
  
  
  CONCLUSIONS
  Our assay is capable of measuring calprotectin concentrations in feces, and has a similar performance to commercially available ELISA methods. Our method is an automated assay system, which is an easier, cheaper, and quicker measurement method than conventional ELISA kits. Therefore, our assay is suitable for daily clinical use.
authors.affiliation: Diagnostic R&D, Alfresa Pharma Corporation, Osaka, Japan. Electronic address: afp-ibaraki-rc@alfresa-pharma.co.jp.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Okuyama
authors.affiliation: Diagnostic R&D, Alfresa Pharma Corporation, Osaka, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Doi
authors.affiliation: Diagnostic R&D, Alfresa Pharma Corporation, Osaka, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Matsuyama
authors.affiliation: Department of Clinical Laboratory, Yokkaichi Hazu Medical Center, Yokkaichi, Japan.
authors.forename: Michiyo
authors.initials: M
authors.lastname: Uchino
authors.affiliation: Inflammatory Bowel Disease Center, Yokkaichi Hazu Medical Center, Yokkaichi, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Yamamoto
mesh_terms: D000328:Adult; D002138:Calibration; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005243:Feces / Q000737:chemistry*; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000175:diagnosis*; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis*; D057230:Limit of Detection; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D013997:Time Factors
chemical_list: D039841:Leukocyte L1 Antigen Complex
keywords: Calprotectin; Colitis; ELISA; Feces; Immunoassay; Inflammatory bowel disease