title: Acute-phase proteins as diagnostic markers in horses with colic.
abstract: OBJECTIVE
  To investigate the diagnostic potential of the concentrations of acute-phase proteins serum amyloid A (SAA), haptoglobin (Hp), and fibrinogen in blood and peritoneal fluid (PF) for differentiating horses with inflammatory colic (entero-colitis and peritonitis) from those with surgical colic.
  
  
  METHODS
  Prospective observational multicenter study.
  
  
  METHODS
  Two university referral hospitals.
  
  
  METHODS
  Horses referred for severe acute abdominal pain to Hospital 1 (n = 148) or Hospital 2 (n = 78).
  
  
  METHODS
  Blood and PF samples collected at admission were used for acute-phase protein concentration measurement.
  
  
  RESULTS
  A multivariable logistic model including clinical parameters (lethargy, rectal temperature >38°C [100.4°F], normal rectal examination findings, and gastric reflux of 5-10 L) recorded at admission was constructed from Hospital 1 data. The ability of the model to correctly differentiate inflammatory from surgical colic was 86% determined as area under the receiver operating characteristic curve. Adding blood parameters (WBC, PCV, total plasma protein, lactate, SAA, Hp, and fibrinogen concentrations) to the logistic model based on clinical parameters revealed that only WBC and SAA and fibrinogen concentrations improved the model. With SAA included in the model no additional blood parameters improved the model, and the final model had an area under the curve of 90%. Addition of PF parameters (hemolysis, total protein concentration, WBC, SAA, or Hp concentrations) did not improve the model. When validated in Hospital 2 data, the models had good integrity and diagnostic performance.
  
  
  CONCLUSIONS
  Evaluation of SAA in serum improved the ability to differentiate horses with acute inflammatory colic requiring medical treatment from horses with colic requiring surgery, as it allowed an additional 4% of horses to be correctly classified into medical and surgical cases. Improved differentiation of these 2 groups of horses with colic may minimize the risk of unnecessary or delayed surgery.
authors.affiliation: Department of Large Animal Sciences, Medicine and Surgery, Faculty of Health and Medical Sciences, University of Copenhagen, 2630 Tåstrup, Denmark. thpi@sund.ku.dk.
authors.forename: Tina H
authors.initials: TH
authors.lastname: Pihl
authors.affiliation: Department of Large Animal Sciences, Veterinary Epidemiology, 1870, Frederiksberg, Denmark.
authors.forename: Elrien
authors.initials: E
authors.lastname: Scheepers
authors.affiliation: Department of Large Animal Sciences, Veterinary Epidemiology, 1870, Frederiksberg, Denmark.
authors.forename: Macarena
authors.initials: M
authors.lastname: Sanz
authors.affiliation: Department of Large Animal Sciences, Veterinary Epidemiology, 1870, Frederiksberg, Denmark.
authors.forename: Amelia
authors.initials: A
authors.lastname: Goddard
authors.affiliation: Department of Large Animal Sciences, Veterinary Epidemiology, 1870, Frederiksberg, Denmark.
authors.forename: Patrick
authors.initials: P
authors.lastname: Page
authors.affiliation: the Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, 0110, Onderstepoort, South Africa.
authors.forename: Nils
authors.initials: N
authors.lastname: Toft
authors.affiliation: Department of Small Animal Clinical Sciences, Central laboratory, 1870, Frederiksberg, Denmark.
authors.forename: Mads
authors.initials: M
authors.lastname: Kjelgaard-Hansen
authors.affiliation: Department of Large Animal Sciences, Medicine and Surgery, Faculty of Health and Medical Sciences, University of Copenhagen, 2630 Tåstrup, Denmark.
authors.forename: Pia H
authors.initials: PH
authors.lastname: Andersen
authors.affiliation: Department of Large Animal Sciences, Medicine and Surgery, Faculty of Health and Medical Sciences, University of Copenhagen, 2630 Tåstrup, Denmark.
authors.forename: Stine
authors.initials: S
authors.lastname: Jacobsen
mesh_terms: D000209:Acute-Phase Proteins / Q000378:metabolism; D000818:Animals; D001202:Ascitic Fluid / Q000378:metabolism; D015415:Biomarkers / Q000097:blood / Q000378:metabolism*; D003085:Colic / Q000175:diagnosis / Q000662:veterinary*; D003718:Denmark; D005260:Female; D005340:Fibrinogen / Q000378:metabolism; D006242:Haptoglobins / Q000378:metabolism; D006734:Horse Diseases / Q000097:blood / Q000175:diagnosis*; D006736:Horses; D008297:Male; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D000685:Serum Amyloid A Protein / Q000378:metabolism
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; D006242:Haptoglobins; D000685:Serum Amyloid A Protein; D005340:Fibrinogen
keywords: diagnostic marker; equine; lactate; peritoneal fluid; serum amyloid A; white blood cell count