title: Association of severe calcium lithogenic activity and bone remodeling markers.
abstract: OBJECTIVE
  To establish cutoff points for markers of bone remodeling that allow for screening of patients at risk for serious lithogenic activity.
  
  
  METHODS
  We conducted a cross-sectional study with 182 patients (aged between 25 and 60 years) divided into 3 groups: group 1, 56 patients without lithiasis; group 2, 67 patients with light calcium lithiasis; and group 3, 59 patients with severe calcium lithiasis. The criteria for inclusion in and exclusion from the study were established, and light and severe lithogenic activity were defined. Metabolic variables in blood and urine, along with bone densitometry, were studied for the groups. Statistical analysis of the results and preparation of receiver operating characteristic curves to establish optimal cutoff points were performed.
  
  
  RESULTS
  The patients in group 3 showed the greatest bone mineral density loss and the highest values for markers of bone remodeling, together with increased 24-hour calciuria. Using the receiver operating characteristic curves developed and based on statistical significance (P = .0001), the following cutoff points for severe lithogenic activity, with a sensitivity between 75% and 85%, were established: β-crosslaps >0.331 ng/mL; osteocalcin >13.2 ng/mL; β-crosslaps/osteocalcin >0.024; 24-hour calciuria >306.6 mg; and fasting urine calcium/creatinine >0.105.
  
  
  CONCLUSIONS
  Patients with calcium lithiasis and elevated values for osteocalcin, β-crosslaps, β-crosslaps/osteocalcin, 24-hour calciuria, and fasting urine calcium/creatinine may present a high risk of severe lithogenic activity.
authors.affiliation: Department of Urology, San Cecilio University Hospital, Granada, Spain. arrabalp@ono.com
authors.forename: Miguel Ángel
authors.initials: MÁ
authors.lastname: Arrabal-Polo
authors.forename: Miguel
authors.initials: M
authors.lastname: Arrabal-Martín
authors.forename: María Sierra
authors.initials: MS
authors.lastname: Girón-Prieto
authors.forename: Jacinto
authors.initials: J
authors.lastname: Orgaz-Molina
authors.forename: Miguel
authors.initials: M
authors.lastname: Quesada-Charneco
authors.forename: Adriana
authors.initials: A
authors.lastname: López-Ruiz
authors.forename: Antonio
authors.initials: A
authors.lastname: Poyatos-Andujar
authors.forename: Armando
authors.initials: A
authors.lastname: Zuluaga-Gómez
authors.forename: Salvador
authors.initials: S
authors.lastname: Arias-Santiago
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D015415:Biomarkers / Q000097:blood / Q000652:urine; D015519:Bone Density; D016723:Bone Remodeling; D002118:Calcium / Q000652:urine; D003094:Collagen / Q000097:blood; D003404:Creatinine / Q000652:urine; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D012372:ROC Curve; D012720:Severity of Illness Index; D052878:Urolithiasis / Q000097:blood* / Q000652:urine*
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C110762:glutamyl-lysyl-alanyl-histidyl-aspartyl-glycyl-glycyl-arginine; D015675:Osteocalcin; D003094:Collagen; D003404:Creatinine; D002118:Calcium