Abstract
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.