title: [Evaluation of bone mineral density, bone turnover markers, the OPG/RANKL system and sTNF-RI in Crohn's disease].
abstract: BACKGROUND
  Patients with Crohn's disease are at risk of developing osteoporosis, a disease in which the inflammatory process seems to be gaining importance. We performed a cross-sectional study to evaluate bone metabolism, osteoclastogenic factors [receptor activator of NF-kB ligand (RANK-L) and osteoprotegerin (OPG)] and soluble tumor necrosis factor-α receptor I (sTNF-RI) in patients with Crohn's disease and to correlate the findings with the degree of disease activity.
  
  
  METHODS
  Sixty-four patients with Crohn's disease from the province of Granada (Spain) were included in this study. Bone mineral density (BMD) was studied through dual X-ray absorptiometry. Immunoassay was used to assess markers of bone formation [bone alkaline phosphatase (bALP) and osteocalcin (OC)] and bone resorption [tartrate resistant acid phosphatase (TRAP) and carboxyterminal telopeptide of type I procollagen (CTX)] as well as RANKL, OPG and sTNF-RI.
  
  
  RESULTS
  The percentage of patients with a Z-score ≤-2 in the femoral neck or lumbar spine was 20.3% and was higher in patients with active disease, although this difference was not significant. This percentage was only higher in patients receiving corticosteroids (11.1 vs. 9.1%; P=.001). Patients with the highest disease activity had higher TRAP levels. No significant differences were found in BMD but significant differences were found in TRAP levels with respect to C-reactive protein concentrations. No association was found between levels of OPG, RANKL and sTNF-RI and BMD or disease activity.
  
  
  CONCLUSIONS
  A substantial proportion of our patients had low BMD. Levels of bone turnover markers suggested higher bone resorption, possibly in relation to disease activity, without a compensatory increase in bone formation.
authors.affiliation: Servicio de Medicina Interna, Hospital General Básico de Santa Ana, Motril, Granada, Spain. danifilax@gmail.com
authors.forename: Daniel
authors.initials: D
authors.lastname: Sánchez Cano
authors.forename: Ricardo
authors.initials: R
authors.lastname: Ruiz-Villaverde
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Olvera Porcel
authors.forename: José Luis
authors.initials: JL
authors.lastname: Callejas Rubio
authors.forename: Carlos Cardeña
authors.initials: CC
authors.lastname: Pérez
authors.forename: María Gómez
authors.initials: MG
authors.lastname: García
authors.forename: Jorge González
authors.initials: JG
authors.lastname: Calvin
authors.forename: Norberto
authors.initials: N
authors.lastname: Ortego Centeno
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015519:Bone Density; D001842:Bone and Bones / Q000378:metabolism*; D003424:Crohn Disease / Q000097:blood / Q000378:metabolism*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D053245:RANK Ligand / Q000097:blood*; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000097:blood*; D055815:Young Adult
chemical_list: D053245:RANK Ligand; D047888:Receptors, Tumor Necrosis Factor, Type I