technetium-tc-99m-pyrophosphate and Calcinosis

Metastatic calcification, a frequent and potential lethal complication of chronic renal failure, is rarely detected before death because of the absence of specific radiographic abnormalities. We report the case of a patient on haemodialysis, with secondary hyperparathyroidism and a second degree A-V block who had a 99m-Tc-pyrophosphate scan to rule out myocardial infarction. The scintigram showed marked myocardial and lung uptake that is indicative of severe metastatic hydroxyapatite calcifications.

Topics: Adult; Calcinosis; Heart; Heart Block; Humans; Hyperparathyroidism, Secondary; Kidney Failure, Chronic; Lung; Male; Myocardium; Technetium Tc 99m Pyrophosphate; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon

Patients with rhabdomyolysis (RBD) and acute renal failure (ARF) are hypocalcemic during the oliguric phase of ARF and over 30% develop hypercalcemia during the diuretic phase. The present study examined the factors underlying these derangements in calcium metabolism in 15 patients: 7 with RBD and ARF, 4 with RBD only, and 4 with ARF only. All patients had hypocalcemia on admission and the hypocalcemia was more pronounced in those with RBD and ARF. All patients with RBD independent of the presence or absence of ARF had calcium deposition in soft tissues as documented by technetium-99 scan. In 4 patients with RBD and ARF, hypercalcemia developed during the diuretic phase at a time when Serum PTH levels were undetectable. Only patients with RBD and ARF had a significant increase in serum levels of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D [1,25(OH)2D] during the diuretic phase and both the increments in and the levels of 1,25(OH)2D were significantly greater in those who were hypercalcemic. The data indicate that 1) hypocalcemia occurs in RBD independent of ARF and is most likely related to calcium deposition in injured tissues, and 2) elevation in serum levels of 1,25(OH)2D plays an important role in the genesis of hypercalcemia during the diuretic phase of patients with RBD and ARF. Our observations suggest that extrarenal production of 1,25(OH)2D may occur in these patients, and/or that the renal production of 1,25(OH)2D may not be so tightly controlled as it is in normal subjects.

Topics: Acute Kidney Injury; Adult; Calcinosis; Calcitriol; Diphosphates; Diuresis; Female; Humans; Hypercalcemia; Hypocalcemia; Male; Middle Aged; Parathyroid Hormone; Radionuclide Imaging; Rhabdomyolysis; Technetium; Technetium Tc 99m Pyrophosphate; Time Factors

A patient with primary hyperparathyroidism whose bone scan showed signs of extensive pulmonary and gastric calcifications is described. The patient also had renal insufficiency. A review of the literature and of data of 13 patients with primary hyperparathyroidism who were seen in the Department of Internal Medicine at the University Hospital of Maastricht, led to the conclusion that only in patients with renal insufficiency could ectopic calcifications be expected to occur. Phosphate retention, rather than the hyperphosphaturia that occurs in that particular situation, is cited as the cause.

Topics: Bone and Bones; Calcinosis; Diphosphates; Humans; Hyperparathyroidism; Lung Diseases; Male; Middle Aged; Radionuclide Imaging; Stomach Diseases; Technetium; Technetium Tc 99m Pyrophosphate

Two cases of chronic renal failure showing very interesting technetium-99m-pyrophosphate bone scans are presented. In both cases striking uptake of activity was shown in the left ventricle of the heart, the mucosa of the stomach and in both lungs. This picture was attributed to metastatic calcification in these organs. Cases of metastatic calcification demonstrated with bone-seeking agents have been presented previously, but have mainly shown intense uptake of activity in the lungs and in a few cases, and to a lesser degree, in the stomach. However, we believe that our cases are unique in showing especially the left ventricle of the heart as well as the mucosa of th stomach with exceptional clarity.

Topics: Adult; Bone and Bones; Calcinosis; Diphosphates; Female; Heart; Humans; Kidney Failure, Chronic; Mucous Membrane; Radionuclide Imaging; Stomach; Technetium; Technetium Tc 99m Pyrophosphate

The spontaneous occurrence of perimyocardial calcification localized in the right ventricle has been reported in an inbred strain of DBA/2 mice. In this paper we examined the correlation between the myocardial uptake ratio of technetium-99m pyrophosphate (99mTc-PYP) and pathological findings in these mice ranging in age from one to 12 months and became lower with age, while calcification and fibrosis in the perimyocardium of the right ventricle became more prominent in aged mice. This may be due to an insidious onset of degeneration with calcification and fibrosis in spontaneously occurring perimyocardial lesions in these mice. Persistent abnormal uptake of 99mTc-PYP observed in the present study suggests the usefulness of such scintigrams in the diagnosis of chronic perimyocardial disease.

Topics: Animals; Calcinosis; Cardiomyopathies; Diphosphates; Heart; Mice; Mice, Inbred DBA; Myocardium; Radionuclide Imaging; Technetium; Technetium Tc 99m Pyrophosphate

Pyrophosphate labeled with 99Tc was evaluated as an indicator of the calcification which occurs after implantation of polymeric materials in rats. Poly(2-hydroxyethyl methacrylate), both porous and homogeneous, had been implanted. 99Tc pyrophosphate was applied intravenously to rats in intervals from 14 days to 15 months. Scintigraphy, x-ray examination, and histology were carried out. The ratio of specific activity in the capsule around the implant to specific activity in the reference tissue was determined. The cumulation of activity was parallel with the development of calcification as revealed by histology. The method can be used not only in the screening test of new polymeric materials, but also in a quantitative determination of the degree of calcification in general.

Topics: Animals; Calcinosis; Diphosphates; Polymers; Prostheses and Implants; Radionuclide Imaging; Rats; Technetium; Technetium Tc 99m Pyrophosphate