title: Effects of Traumatic Amputation on β-Trace Protein and β2-Microglobulin Concentrations in Male Soldiers.
abstract: BACKGROUND
  Serum creatinine (SCr) levels are decreased following traumatic amputation, leading to the overestimation of glomerular filtration rate (GFR). β-Trace protein (BTP) and β2-microglobulin (B2M) strongly correlate with measured GFR and have not been studied following amputation. We hypothesized that BTP and B2M would be unaffected by traumatic amputation.
  
  
  METHODS
  We used the Department of Defense Serum Repository to compare pre- and post-traumatic amputation serum BTP and B2M levels in 33 male soldiers, via the N Latex BTP and B2M nephelometric assays (Siemens Diagnostics, Tarrytown, N.Y., USA). Osterkamp estimation using DEXA scan measurements was used to establish percent estimated body weight loss (%EBWL). Results were analyzed for small (3-5.9% EBWL), medium (6-13.5%), and large (>13.5%) amputation subgroups; and for a control group matched 1:1 to the 12 large amputation subjects. Paired Student's t test was used for comparisons.
  
  
  RESULTS
  Mean serum BTP levels were unchanged in controls, all amputees, and the small and medium amputation subgroups. BTP appeared to decrease following large %EBWL amputation (p = 0.05). Mean serum B2M levels were unchanged in controls, all amputees, and the small and medium amputation subgroups. B2M appeared to increase following large %EBWL amputation (p = 0.05).
  
  
  CONCLUSIONS
  BTP and B2M levels are less affected than SCr by amputation, and should be considered for future study of GFR estimation. BTP and B2M changes following large %EBWL amputation require validation and may offer insight into non-GFR BTP and B2M determinants as well as increased cardiovascular disease and mortality following amputation.
authors.affiliation: Nephrology Service, Department of Medicine, Walter Reed National Military Medical Center, Bethesda, Md., USA.
authors.forename: Dustin J
authors.initials: DJ
authors.lastname: Little
authors.forename: Christina M
authors.initials: CM
authors.lastname: Yuan
authors.forename: John S
authors.initials: JS
authors.lastname: Thurlow
authors.forename: Verena
authors.initials: V
authors.lastname: Gounden
authors.forename: Sonia Q
authors.initials: SQ
authors.lastname: Doi
authors.forename: Alison
authors.initials: A
authors.lastname: Pruziner
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Abbott
authors.forename: Brett J
authors.initials: BJ
authors.lastname: Theeler
authors.forename: Stephen W
authors.initials: SW
authors.lastname: Olson
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D000673:Amputation, Traumatic / Q000097:blood*; D001835:Body Weight; D001930:Brain Injuries; D016022:Case-Control Studies; D003404:Creatinine / Q000097:blood; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D019746:Intramolecular Oxidoreductases / Q000097:blood*; D007677:Kidney Function Tests; D054834:Lipocalins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D008889:Military Personnel; D015233:Models, Statistical; D009391:Nephelometry and Turbidimetry; D012042:Registries; D014481:United States; D015431:Weight Loss; D055815:Young Adult; D001613:beta 2-Microglobulin / Q000097:blood*
chemical_list: D054834:Lipocalins; D001613:beta 2-Microglobulin; D003404:Creatinine; D019746:Intramolecular Oxidoreductases; C022466:prostaglandin R2 D-isomerase