title: Reduced muscle mass and bone size in pediatric patients with inflammatory bowel disease.
abstract: BACKGROUND
  Decreased bone mineral density has been reported in children with inflammatory bowel disease (IBD). We used peripheral quantitative computed tomography (pQCT) to assess bone mineralization, geometry, and muscle cross-sectional area (CSA) in pediatric IBD.
  
  
  METHODS
  In a cross-sectional study, pQCT of the forearm was applied in 143 IBD patients (mean age 13.9 +/- 3.5 years); 29% were newly diagnosed, 98 had Crohn's disease, and 45 had ulcerative colitis. Auxological data, cumulative glucocorticoid dose, disease activity indices, laboratory markers for inflammation, and bone metabolism were related to the results of pQCT.
  
  
  RESULTS
  Patients were compromised in height (-0.82 +/- 1.1 SD), weight (-0.77 +/- 1.0 SD), muscle mass (-1.12 +/- 1.0 SD), and total bone cross-sectional area (-0.79 +/- 1.0 SD) compared to age- and sex-matched healthy controls (z-scores). In newly diagnosed patients, the ratio of bone mineral mass per muscle CSA was higher than in those with longer disease duration (1.00 versus 0.30, P = 0.007). Serum albumin level and disease activity correlated with muscle mass, accounting for 41.0% of variability in muscle mass (P < 0.01). The trabecular bone mineral density z-score was on average at the lower normal level (-0.40 +/- 1.3 SD, P < 0.05).
  
  
  CONCLUSIONS
  Reduced bone geometry was explained only in part by reduced height. Bone disease in children with IBD seems to be secondary to muscle wasting, which is already present at diagnosis. With longer disease duration, bone adapts to the lower muscle CSA. Serum albumin concentration is a good marker for muscle wasting and abnormal bone development.
authors.affiliation: Division of Pediatric Endocrinology, Dr. v. Haunersches Kinderspital, University, Munich, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Bechtold
authors.forename: Martin
authors.initials: M
authors.lastname: Alberer
authors.forename: Tina
authors.initials: T
authors.lastname: Arenz
authors.forename: Stefanie
authors.initials: S
authors.lastname: Putzker
authors.forename: Birgit
authors.initials: B
authors.lastname: Filipiak-Pittroff
authors.forename: Hans Peter
authors.initials: HP
authors.lastname: Schwarz
authors.forename: Sibylle
authors.initials: S
authors.lastname: Koletzko
mesh_terms: D000293:Adolescent; D001827:Body Height; D015519:Bone Density; D001842:Bone and Bones / Q000473:pathology*; D002648:Child; D003093:Colitis, Ulcerative / Q000188:drug therapy / Q000473:pathology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D015212:Inflammatory Bowel Diseases / Q000188:drug therapy / Q000473:pathology*; D008297:Male; D009132:Muscles / Q000473:pathology*; D009929:Organ Size; D012720:Severity of Illness Index; D013997:Time Factors; D015898:Tomography Scanners, X-Ray Computed; D055815:Young Adult
chemical_list: D007166:Immunosuppressive Agents