title: Increased technetium-99 m hydroxy diphosphonate soft tissue uptake on bone scintigraphy in chronic kidney disease patients with secondary hyperparathyroidism: correlation with hyperphosphataemia.
abstract: In bone scan patients with dialysis-treated chronic kidney disease (CKD) and hyperparathyroidism, soft tissue accumulation of technetium-99 m hydroxy/methylene diphosphonate (Tc-99 m-HDP/MDP) has been reported primarily in case reports and usually explained by hypercalcaemia and/or hyperphosphataemia. As human vascular smooth muscle cells produce hydroxyapatite during cell culture with increased phosphate levels and as Tc-99 m-HDP/MDP primarily binds to hydroxyapatite, we hypothesized that soft tissue accumulation would be found in patients with hyperphosphataemia. We identified 63 CKD patients diagnosed with secondary hyperparathyroidism admitted for Tc-99 m-HDP bone scan. Baseline characteristics and mean concentrations of biochemical markers (including P-calcium and P-phosphate) taken 0-3 months prior to the bone scans were collected. Soft tissue uptake was detected on bone scans in 37 of 63 (59%) patients. Primary locations were in the heart (27/37 = 73%), muscles (12/37 = 32%), lung (9/37 = 24%) and gastrointestinal tract (6/37 = 16%), and 13 of 37 (35%) patients had simultaneous uptake in more than one location. Regarding biochemical markers, patients with soft tissue uptake only differed from patients without in terms of plasma phosphate levels (1·95 ± 0·15 (n = 37) versus 1·27 ± 0·08 (n = 26), P = 0·0012). All patients with myocardial uptake (n = 27) had a coronary arteriography-verified history of coronary artery disease (CAD), whereas CAD was only present in six of the 36 patients without myocardial uptake. In conclusion, dialysis-treated CKD patients with secondary hyperparathyroidism have a high incidence of soft tissue uptake, and this finding is strongly correlated with elevated phosphate, but not calcium values.
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Lotte Hahn
authors.initials: LH
authors.lastname: Enevoldsen
authors.affiliation: Department of Nephrology, Herlev Hospital, Herlev, Denmark.
authors.forename: James
authors.initials: J
authors.lastname: Heaf
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Liselotte
authors.initials: L
authors.lastname: Højgaard
authors.affiliation: Department of Clinical Physiology, Herlev Hospital, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Bo
authors.initials: B
authors.lastname: Zerahn
authors.affiliation: Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Philip
authors.initials: P
authors.lastname: Hasbak
mesh_terms: D001842:Bone and Bones / Q000000981:diagnostic imaging* / Q000378:metabolism; D002118:Calcium / Q000097:blood; D017023:Coronary Angiography; D017886:Durapatite / Q000378:metabolism; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000000981:diagnostic imaging / Q000378:metabolism; D006962:Hyperparathyroidism, Secondary / Q000097:blood / Q000000981:diagnostic imaging* / Q000209:etiology; D054559:Hyperphosphatemia / Q000097:blood / Q000000981:diagnostic imaging* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D010710:Phosphates / Q000097:blood; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals / Q000378:metabolism*; D006435:Renal Dialysis; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000150:complications* / Q000175:diagnosis / Q000628:therapy; D012189:Retrospective Studies; D013669:Technetium Tc 99m Medronate / Q000031:analogs & derivatives* / Q000378:metabolism; D051598:Whole Body Imaging
chemical_list: D010710:Phosphates; D019275:Radiopharmaceuticals; C024226:technetium Tc 99m hydroxymethylene diphosphonate; D017886:Durapatite; D002118:Calcium; D013669:Technetium Tc 99m Medronate
keywords: Tc-99 m-HDP; atherosclerosis; bone scan; hyperparathyroidism; soft tissue uptake