Clemens Wirth MD, Presenter: Nothing to Disclose

Mirjam Rott, Abstract Co-Author: Nothing to Disclose

Christine Beck, Abstract Co-Author: Nothing to Disclose

Dietbert Hahn MD, Abstract Co-Author: Nothing to Disclose

Hermann Girschick MD, PhD, Abstract Co-Author: Nothing to Disclose

Meinrad Johannes Beer MD, Abstract Co-Author: Nothing to Disclose

Although Hypophosphatasia (HP) is a rare inherited disorder of bone mineralisation, it should be included in the differential diagnosis of inflammatory bone disorders in children. In this retrospective study of a group of patients with infantile and childhood HP we tried to evaluate specific abnormalities in conventional x-rays which may lead to the diagnosis.  

90 conventional x-ray images of different regions of the body from 24 HP patients (age median four (0-16) years; 10 females, 14 males) were retrospectively evaluated by two experienced radiologists in consensus using standardized evaluation forms. The sheets contained 65 items to assess bone mineralisation and bone deformation. The findings were compared to age and sex correlated healthy individuals and to the serum level of alkaline phosphatase (aP).  

Statistically significant differences (p<0,05) in comparison to the control group could be found in 15 (23%) items: Skull: indirect signs of intracranial pressure and synostosis of the sagittal fissure. Thorax: increased diameter of the ribs, rachitic changes, enlarged ventral ribs. Extremities: bowing of the tubular bones in proximity of the knee, rachitic changes, metaphyseal hypomineralisation, epimetaphyseal and metadiaphyseal mineralisation differences of tubular bones forming knee and wrist articulation. There was no correlation between severity of osseous changes and level of serum aP.  

15 of 65 items showed significant differences in HP patients compared to healthy controls.   

Diagnostic workup of infantile and childhood HP should include x-rays of the skull, thorax, knee and wrist.  

Wirth, C, Rott, M, Beck, C, Hahn, D, Girschick, H, Beer, M, Infantile and Childhood Hypophosphatasia: Spectrum of Radiologic Findings.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9003225.html