losartan-potassium and Calcinosis

Tumoral calcinosis is a rare form of soft tissue calcifications, initially described as an idiopathic condition, which could occur in uremic patients. Despite its distinct clinical and morphologic presentations, the underlying pathogenesis is unknown. We present a dialysis patient who developed tumoral calcinosis over the right shoulder after receiving a misplaced injection of human recombinant erythropoietin probably into the periarticular tissue. This case serves as an example highlighting the importance of periarticular inflammatory reaction in precipitating the development of the lesion in predisposed patients.

Topics: Administration, Oral; Adult; Bursa, Synovial; Calcinosis; Calcium; Calcium Carbonate; Dialysis Solutions; Erythropoietin; Female; Glomerulonephritis, IGA; Humans; Hypercalcemia; Hyperplasia; Injections, Intramuscular; Kidney Failure, Chronic; Leukocytosis; Parathyroid Hormone; Patient Compliance; Peritoneal Dialysis, Continuous Ambulatory; Radiography; Recombinant Proteins; Shoulder Joint

Vascular calcifications are frequent in hemodialysis patients. Its incidence ranges from 25 to 67% depending of different series. Thirty hemodialysis patients were selected from a dialysis population of 150 patients. These 30 patients were divided into two groups: group I included 15 hemodialysis patients with severe secondary hyperparathyroidism and severe, roentgenographically visible diffuse vascular calcifications, and group II included 15 other hemodialysis patients with moderate hyperparathyroidism without radiographic evidence of arterial calcifications. The control group comprised 20 normal volunteers. In all patients, measurements of protein C activity, free protein S and intact parathyroid hormone (PTH) were performed. Statistical analysis showed that free protein S in the patients of group I had a tendency to be lower than in the patients of group II (p < 0.01) and the control group (p < 0.001). We did not find significant differences in free protein S between group II and control group patients nor a significant correlation between intact PTH and free protein S in groups I and II. Protein C activity was found to be in the normal range in both groups. Free protein S deficiency in patients of group I would suggest a synthesis defect by impaired endothelial cells-due to vascular calcifications (?). Free protein S deficiency could increase the risk of thrombotic complications in these patients.

Topics: Adult; Calcinosis; Erythropoietin; Female; Humans; Male; Middle Aged; Parathyroid Hormone; Protein C; Protein S; Protein S Deficiency; Recombinant Proteins; Reference Values; Renal Dialysis; Vascular Diseases

Adult female Wistar rats were injected with 1 mg/kg body weight of uranyl nitrate (UN). Evaluation of renal function, histopathology studies, and determination of plasma erythropoietin (Ep) titers after exposure to 456 mb for 16 h were performed at 1, 2, 7, 10, 15, and 21 days after drug injection. Plasma urea and creatinine concentrations markedly increased during the first seven days after injection, reaching maximal values on day 7 and decreasing thereafter. Significant increases in urine volume and significant depressions in urine osmolality also were observed; both alterations were most marked on day 7 after injection. A coagulative necrosis of the epithelium of proximal convoluted tubules, desquamation of the necrotic cells, and dilation or collapse of the tubular lumen were observed; the lesions were more marked on day 7. Plasma Ep levels in UN-treated rats exposed to hypobaria were markedly lower than in noninjected controls similarly exposed. Measurements were performed one, two, and seven days after UN injection, with maximal depression observed on day 7. These observations indicate that there is a correlation between the extent of both tubule damage and degree of renal dysfunction and plasma Ep production during exposure to hypoxia in UN-treated rats. This suggests that the renal Ep component is derived primarily from tubular cells.

Topics: Acute Kidney Injury; Animals; Blood Urea Nitrogen; Body Weight; Calcinosis; Erythropoietin; Feeding Behavior; Female; Organ Size; Oxygen; Rats; Time Factors; Uranyl Nitrate; Water-Electrolyte Balance