Humans ; Mesenchymoma/surgery* ; Soft Tissue Neoplasms ; Osteomalacia

Hypophosphatemic osteomalacia is a rare form of metabolic bone disorder in neurofibromatosis type 1 (NF1). The exact disease mechanism of this disorder in NF1 is yet to be established. We present a 44-year-old female known to have NF1, who presents with debilitating bone pain, weakness and multiple fractures. Laboratory investigations showed persistent hypophosphatemia with renal phosphate wasting suggestive of hypophosphatemic osteomalacia. She also had concomitant vitamin D deficiency which contributed to the disease severity. Medical therapy with oral phosphate and vitamin D improved her symptoms without significant changes in fracture healing or phosphate levels.
Hypophosphatemia ; Osteomalacia ; FGF23 ; Vitamin D Deficiency

Aluminum (Al) is the third most abundant element in the earth's crust and is omnipresent in our environment, including our food. However, with normal renal function, oral and enteral ingestion of substances contaminated with Al, such as antacids and infant formulae, do not cause problems. The intestine, skin, and respiratory tract are barriers to Al entry into the blood. However, contamination of fluids given parenterally, such as parenteral nutrition solutions, or hemodialysis, peritoneal dialysis or even oral Al-containing substances to patients with impaired renal function could result in accumulation in bone, parathyroids, liver, spleen, and kidney. The toxic effects of Al to the skeleton include fractures accompanying a painful osteomalacia, hypoparathyroidism, microcytic anemia, cholestatic hepatotoxicity, and suppression of the renal enzyme 25-hydroxyvitamin D-1 alpha hydroxylase. The sources of Al include contamination of calcium and phosphate salts, albumin and heparin. Contamination occurs either from inability to remove the naturally accumulating Al or from leeching from glass columns used in compound purification processes. Awareness of this long-standing problem should allow physicians to choose pharmaceutical products with lower quantities of Al listed on the label as long as this practice is mandated by specific national drug regulatory agencies.
Aluminum ; Anemia ; Antacids ; Calcium ; Eating ; Glass ; Heparin ; Humans ; Hypoparathyroidism ; Infant Formula ; Intestines ; Kidney ; Leeching ; Liver ; Osteomalacia ; Parathyroid Glands ; Parenteral Nutrition Solutions ; Peritoneal Dialysis ; Pharmaceutical Preparations ; Renal Dialysis ; Respiratory System ; Salts ; Skeleton ; Skin ; Spleen

⁶⁸Ga-DOTATATE uptake in mesenchymal tumors causing hypophosphatemic osteomalacia has been recently described. Herein, we present a case of ⁶⁸Ga-DOTATATE uptake in an intramastoid phosphaturic mesenchymal tumor that had not been depicted in previous (99m)Tc-Sestamibi and ¹⁸F-FDG scans. The lesion was surgically removed and the phosphorus level increased to the normal range.
Mastoid ; Osteomalacia ; Phosphorus ; Positron-Emission Tomography and Computed Tomography ; Reference Values

This case report concerns a 34-year-old woman who had been diagnosed with ankylosing spondylitis (AS), fibromyalgia syndrome (FMS), osteoarthritis (OA), lumbar disc herniation and the like in different hospitals during the past 18 months. She had progressive osteoarthrosis, significant muscle weakness, gait abnormalities in weightbearing areas, however without typical inflammatory low back pain, while the treatment with non-steroidal anti-inflammatory drugs (NSAIDs) was invalid, with normal inflammation index, negative results for rheumatic factor (RF) and human leukocyte antigen (HLA)-B27, and normal erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). She had hyphosphatemia, normal serum calcium, 1,25-(OH)2-D3 reduction, elevated alkaline phosphatase (ALP) and normal parathyroid hormone (PTH), however with elevated urinary phosphorus. Finally, the medial thigh nodule was found in the subcutaneous of her inner leg by careful examination and imaging scans including B-ultrasound and PET/CT. The final pathology confirmed that the nodule was phosphate urinary mesenchymal tumors. After the tumor was removed, the patient was treated with anti-osteoporosis and phosphorus supplementation. The symptoms of bone pain and muscle weakness were alleviated, and hypophosphatemia was corrected. It was confirmed that the patient had low-phosphorus osteomalacia due to tumor. Tumor-induced hypophosphatemia osteomalacia (TIO) was a rare paraneoplastic syndrome which was caused by excessive phosphorus excretion induced by the tumor, and was thus categorized as an acquired hypophosphatemic osteomalacia. TIO had an occult onset and was associated with a high rate of misdiagnosis, although TIO has some typical clinical features. Early diagnosis, correctly positioning of the tumor, and surgical resection can achieve good outcomes.
Adult ; Endocrine System Diseases ; Female ; Humans ; Hypophosphatemia ; Neoplasms, Connective Tissue ; Osteomalacia ; Positron Emission Tomography Computed Tomography

No abstract available.
Fractures, Bone ; Osteomalacia

Objective To analyze Ga-DOTA-TATE positron emission tomography/computed tomography (PET/CT) imaging features of tumor-indud osteomalacia (TIO) patients with negative Tc-HYNIC-TOC single photo emission computed tomography (SPECT) findings and to investigate the value of Ga-DOTA-TATE PET/CT in accurate localization of culprit tumors.Methods We retrospectively analyzed Ga-DOTA-TATE PET/CT imaging features including location,size,density,the maximum and mean standardized uptake value in 37 TIO patients with negative Tc-HYNIC-TOC SPECT findings.Results Totally 37 solitary TIO tumors,including 35 phosphaturic mesenchymal tumors and 2 spindle cell tumors confirmed by pathological examinations,were detected via Ga-DOTA-TATE PET/CT scans in the included 37 cases. These 37 TIO tumors showed obviously increased activities,with an maximum standardized uptake value of 7.2±4.3 and mean standardized uptake value of 4.3±2.4. The average maximum diameter was (1.9±0.7) cm. The majority of the tumors occurred in the lower extremities (19/37),followed by the trunk (11/37),maxillary/mandibular bone (5/37),and upper extremities (2/37). In addition,24 bone lesions were located in long bones of lower extremities (13/24),most of which demonstrated eccentric growth (8/13). Osteolytic changes (14/24) were observed mainly in the lesions via the corresponding CT imaging;meanwhile,sclerotic changes presented in nine cases. Of the 13 soft-tissue lesions,the majority (10/13) showed well-circumscribed isodense or hypodense nodules on the CT images,with spot calcification in one lesion located in the pleura.Conclusions Ga-DOTA-TATE PET/CT scans can detect the TIO culprit tumors miss-diagnosed by Tc-HYNIC-TOC SPECT. Somatostatin-receptors highly expressed lesions with focal osteolytic or osteosclerotic change in bone and isodense or hypodense nodules in soft tissue will favor the diagnosis of TIO tumors.
Humans ; Neoplasms ; complications ; diagnostic imaging ; Octreotide ; analogs & derivatives ; Organotechnetium Compounds ; Osteomalacia ; diagnostic imaging ; etiology ; Positron Emission Tomography Computed Tomography ; Retrospective Studies

The long-term use of adefovir and tenofovir–antiviral medications commonly used to treat chronic hepatitis B–can be associated with proximal renal tubular dysfunction resulting in significant hypophosphatemic osteomalacia. However, there have been few reports about pathological fractures requiring surgical stabilization in cases of antiviral drug-induced hypophosphatemic osteomalacia. We present the case of a 51-year-old man who sustained bilateral pathological hip fractures associated with antiviral drug-induced hypophosphatemic osteomalacia. To treat a lamivudine-resistant hepatitis-B viral infection, the patient received adefovir for 7 years followed by tenofovir for the subsequent 3 years. He had suffered from polyarthralgia and generalized weakness for 2 years prior to presentation at our clinic. Misdiagnosis and inadequate management of his condition accelerated weakness of the bone matrix and ultimately induced pathological fractures. The patient was managed via cementless total hip arthroplasty on the left hip and internal fixation on the right hip. This case highlights that orthopaedic surgeons should consider the possibility of hypophosphatemic osteomalacia if patients receiving antiviral drugs complain of polyarthralgia and generalized weakness.
Antiviral Agents ; Arthralgia ; Arthroplasty, Replacement, Hip ; Bone Matrix ; Diagnostic Errors ; Fanconi Syndrome ; Fractures, Spontaneous ; Hepatitis B ; Hepatitis ; Hepatitis, Chronic ; Hip Fractures ; Hip ; Humans ; Middle Aged ; Osteomalacia ; Surgeons ; Tenofovir

Tumor-induced osteomalacia (TIO), also known as oncogenic osteomalacia, is a rare paraneoplastic syndrome characterized by hypophosphatemia resulting from decreased tubular phosphate reabsorption, with a low or inappropriately normal level of active vitamin D. The culprit tumors of TIO could produce fibroblast growth factor 23 which plays a role in regulating renal Pi handling and 25-hydroxyvitamin D 1α-hydroxylase activity. Chronic hypophosphatemia could eventually lead to inadequate bone mineralization, presenting as osteomalacia. The diagnosis should be considered when patients manifest as hypophosphatemia and osteomalacia, or rickets and needs to be differentiated from other disorders of phosphate metabolism, such as the inhereditary diseases like X-linked hypophosphataemic rickets, autosomal dominant hypophosphataemic rickets, autosomal recessive hypophosphataemic rickets and acquired diseases like vitamin D deficiency. Localization of responsible tumors could be rather difficult since the vast majority are very small and could be everywhere in the body. A combination of thorough physical examination, laboratory tests and imaging techniques should be applied and sometimes a venous sampling may come into handy. The technology of somatostatin-receptor functional scintigraphy markedly facilitates the localization of TIO tumor. Patients undergoing complete removal of the causative neoplasm generally have favorable prognoses while a few have been reported to suffer from recurrence and metastasis. For those undetectable or unresectable cases, phosphate supplements and active vitamin D should be administrated and curative intended radiotherapy or ablation is optional.
Calcification, Physiologic ; Diagnosis ; Fibroblast Growth Factors ; Humans ; Hypophosphatemia ; Metabolism ; Neoplasm Metastasis ; Osteomalacia ; Paraneoplastic Syndromes ; Physical Examination ; Prognosis ; Radionuclide Imaging ; Radiotherapy ; Recurrence ; Rickets ; Vitamin D ; Vitamin D Deficiency

Fanconi syndrome is a dysfunction of the proximal renal tubules that results in impaired reabsorption and increased urinary loss of phosphate and other solutes. The pathophysiology of drug-induced Fanconi syndrome is unclear. Here we report the case of a 36-year-old woman who presented with pain in multiple bones and proteinuria. She had a 7-year history of taking adefovir at 10 mg/day for chronic hepatitis B. Three years previously she had received surgery for a nontraumatic right femur neck fracture, after which she continued to complain of pain in multiple bones, and proteinuria, glycosuria, and phosphaturia were noted. The findings of a light-microscope examination of a renal biopsy sample were normal, but mitochondrial damage of the proximal tubules was evident in electron microscopy. Western blot analysis revealed that the level of serum fibroblast growth factor 23 (FGF23) was lower than in normal controls. After 2 months of treatment, hypophosphatemia and proximal tubular dysfunction were reversed, and serum FGF23 had normalized. This case suggests that direct mitochondrial damage in proximal tubules can cause drug-induced Fanconi syndrome associated with osteomalacia.
Adult ; Biopsy ; Blotting, Western ; Fanconi Syndrome* ; Female ; Femoral Neck Fractures ; Fibroblast Growth Factors ; Glycosuria ; Hepatitis B, Chronic ; Humans ; Hypophosphatemia ; Hypophosphatemia, Familial ; Kidney Tubules, Proximal ; Microscopy, Electron ; Mitochondria ; Osteomalacia* ; Proteinuria