Vertebral Fractures as a Manifestation of Phosphaturic Mesenchymal Tumor-Induced Osteomalacia

Background. The rarity of the disease and, in this regard, the lack of doctors awareness about the pathology, late diagnosis and severe complications of the musculoskeletal system emphasize the relevance of clinical case demonstrating. The uniqueness of  the  case  lies  in  the  fact  that  hypophosphatemia,  noted  3  years  after  the  disease  debut,  was  not  taken  into  account. Case description. A 45-year-old patient with complaints of muscle weakness, gait disorders, torso deformity and multiple vertebral body fractures that appeared against the background of any somatic diseases absence, a differential diagnosis of metastatic vertebral bodies lesions and secondary osteoporosis complicated by vertebral body fractures was carried out for four years in various hospitals, and was even treated with bisphosphonates. Against this background, the chest deformity increased,  kyphosis  and  remodeling  fractures  of  other  bones  appeared.  The  assessment  of  calcium  and  phosphorus homeostasis  was  first  performed  at  the  4th year  of  the  disease,  but  the  detected  hypophosphatemia  was  not  regarded as  a  manifestation  of  hypophosphatemic  osteomalacia. Conclusion. Among  adult  patients  with  multiple  low-energy fractures,  severe  muscle  weakness  and  bone  pain  that  appeared  against  the  background  of  complete  health,  to  exclude hypophosphatemic osteomalacia induced by mesenchymal tumor, it is necessary to include the level of phosphorus in blood and daily urine assessment in the diagnostic algorithm.