Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033687 (proteinuria)
 24,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Patients with nephrotic syndrome have low blood levels of 25 hydroxyvitamin D (25-OH-D) most probably because of losses in urine, and a vitamin D-deficient state may ensue. The biological consequences of this phenomenon on target organs of vitamin D are not known. This study evaluates one of these target organs, the bone. Because renal failure is associated with bone disease, we studied six patients with nephrotic syndrome and normal renal function. The glomerular filtration rate was 113+/-2.1 (SE) ml/min; serum albumin, 2.3+/-27 g/dl; and proteinuria ranged between 3.5 and 14.7 g/24 h. Blood levels of 25-OH-D, total and ionized calcium and carboxy-terminal fragment of immunoreactive parathyroid hormone were measured, and morphometric analysis of bone histology was made in iliac crest biopsies obtained after double tetracycline labeling. Blood 25-OH-D was low in all patients (3.2-5.1 ng/ml; normal, 21.8+/-2.3 ng/ml). Blood levels of both total (8.1+/-0.12 mg/dl) and ionized (3.8+/-0.21 mg/dl) calcium were lower than normal and three patients had true hypocalcemia. Blood immuno-reactive parathyroid hormone levels were elevated in all. Volumetric density of osteoid was significantly increased in three out of six patients and the fraction of mineralizing osteoid seams was decreased in all. Evidence for an increase in active lacunae (bone-osteoclast interface) occurred in three out of six patients and in inactive (Howship's lacunae) bone resorption in six out of six. The data indicate that the loss of 25-OH-D in urine of patients with nephrotic syndrome and normal renal function may result in a decrease of blood levels of ionized calcium, secondary hyperparathyroidism and enhanced bone resorption. In addition, the vitamin D-deficient state causes osteomalacia as evidenced by defective mineralization and increased osteoid volume.
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PMID:Osteomalacia and hyperparathyroid bone disease in patients with nephrotic syndrome. 42 68

The blood levels of 25-hydroxyvitamin D (25-HCC) in 26 patients with nephrotic syndrome (proteinuria of 6.5 g/24 h +/- 0.8 SEM) ranged between 1 and 18.6 ng/ml (8.6 +/- 1.0 SEM). This value was significantly lower (P less than 0.01) than that in normal subjects (21.8 +/- 2.3 ng/ml) and patients with chronic renal failure (24.8 +/- 2.3 ng/ml). There was inverse correlation (P less than 0.01) between levels of 25-HCC and magnitude of proteinuria and a direct relation (P less than 0.01) with serum albumin. Reduction in proteinuria was rapidly followed by a rise in blood 25-HCC toward normal. Ionized calcium levels were low in 16 of 26 nephrotic patients irrespective of degree of renal failure. In four of seven nephrotic patients with normal renal function, ionized calcium levels were low and showed an inverse relation with levels of parathyroid hormone. These data show that patients with nephrotic syndrome have low blood levels of 25-HCC probably due to its loss in urine. This derangement is probably responsible for the disorders of calcium metabolism in nephrosis.
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PMID:Blood levels of 25-hydroxyvitamin D in nephrotic syndrome. Studies in 26 patients. 93 Dec 2

We report a patient who developed persistent nephrogenic diabetes insipidus associated with renal tubular acidosis, renal resistance to parathyroid hormone, aminoaciduria and proximal tubule pattern proteinuria in the presence of a reduced glomerular filtration rate (19-24 ml/min). A review of the previous reports of persistent nephrogenic diabetes insipidus revealed that in all patients the glomerular filtration rate had been less than 60 ml/min at presentation. Chronic renal failure may therefore predispose to the development of persistent nephrogenic diabetes insipidus in patients receiving lithium.
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PMID:Persistent nephrogenic diabetes insipidus, tubular proteinuria, aminoaciduria, and parathyroid hormone resistance following longterm lithium administration. 217 Sep 60

A prospective multicenter study was designed to determine the frequency and prognostic importance of hypercalciuria in children with hematuria. Urinary calcium excretion was examined in 215 patients with unexplained isolated hematuria (no proteinuria, urolithiasis, infection or systemic disorder). Hypercalciuria (urinary calcium excretion greater than 4 mg/kg/day) was identified in 76 patients (35%). Compared to patients with normal urinary calcium excretion, children with hematuria and hypercalciuria were characterized by male preponderance, white race, family history of urolithiasis, gross hematuria and calcium oxalate crystals. Renal biopsies were performed in 10 patients with urinary calcium excretion 0.4 to 2.5 mg/kg/day; three had IgA glomerulonephritis, three had glomerular basement membrane thinning, one had proliferative glomerulonephritis and three were normal. Renal biopsies in three patients with hypercalciuria showed focal segmental glomerulosclerosis, hereditary nephritis or no abnormalities. Oral calcium loading tests showed renal hypercalciuria in 26 patients, absorptive hypercalciuria in 15 patients and were not diagnostic in 35 patients. Serum parathyroid hormone, bicarbonate and phosphorus and urinary cyclic adenosine monophosphate concentrations were similar in the three groups of hypercalciuric patients. Urinary calcium excretion after one week of dietary calcium restriction was higher (5.8 mg/kg/day) in renal hypercalciuria than in other hypercalciuric patients (3.4 mg/kg/day), P less than 0.01. One to four years follow-up was available for 184 patients. Eight of 60 hypercalciuric patients developed urolithiasis or renal colic compared to 2 of 124 patients with normal urinary calcium excretion (P less than 0.001). Hypercalciuria is commonly associated with isolated hematuria and represents a risk factor for future urolithiasis in children with hematuria.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Idiopathic hypercalciuria: association with isolated hematuria and risk for urolithiasis in children. The Southwest Pediatric Nephrology Study Group. 240 91

Recent studies indicate that serum levels of osteocalcin, a 49-aminoacid bone matrix protein, are a biochemical marker of bone formation. In order to study bone metabolism in diabetes mellitus, in 28 patients with Type 1 (insulin-dependent) diabetes mellitus, in 38 patients with Type 2 (non-insulin-dependent) diabetes mellitus and two control groups, matched for Type 1 and Type 2 diabetic patients, respectively, serum levels of osteocalcin, parathyroid hormone and 25 hydroxy vitamin D were measured by radioimmunoassay. Whereas in Type 1 diabetic patients and control subjects serum levels of osteocalcin and 25 hydroxy vitamin D were not statistically different, serum osteocalcin and 25 hydroxy vitamin D levels were significantly decreased in Type 2 diabetic patients when compared with corresponding control subjects (p less than 0.03 and p less than 0.001, respectively). Independent of the type of diabetes, serum parathyroid hormone levels were comparable in diabetic patients and matched control subjects. Serum osteocalcin levels were significantly lower in Type 1 diabetic patients with retinopathy and/or proteinuria than in Type 1 diabetic patients without microangiopathy (p less than 0.05). Whereas serum parathyroid hormone levels in Type 2 diabetic patients with retinopathy and/or proteinuria were significantly increased (p less than 0.02), 25 hydroxy vitamin D levels were decreased (p less than 0.02) when compared with Type 2 diabetic patients without microangiopathy. Our data give evidence of a vitamin D deficiency and a decreased bone formation in patients with Type 2 diabetes mellitus. In Type 1 diabetes mellitus bone formation as reflected by serum osteocalcin levels is influenced by the presence or absence of microangiopathic complications.
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PMID:Serum osteocalcin levels in diabetes mellitus: analysis of the type of diabetes and microvascular complications. 326 86

The serum concentrations of calcium, phosphorus, parathyroid hormone, vitamin D3 metabolites and their transport protein (DBP) were measured in 18 patients with the nephrotic syndrome (mean daily proteinuria 8.8 g). The glomerular filtration rate was normal in 13 patients while the remaining 5 had a mild degree of renal failure. The serum concentrations of total protein, albumin and DBP were significantly decreased in patients with the nephrotic syndrome. The serum calcium concentration was decreased but the calculated ionized calcium concentration remained normal. The serum concentrations of 25-hydroxycholecalciferol (5.3 +/- 3.1 micrograms/l) and 1,25-dihydroxycholecalciferol [1,25-(OH)2D3 (20 +/- 12 ng/l)] were significantly lower in patients with the nephrotic syndrome and normal glomerular filtration rates than in normal controls (14.4 +/- 4 micrograms/l and 42 +/- 13 ng/l, respectively). The free 1,25-(OH)2D3 index was also significantly below normal (0.9 +/- 0.4 vs. 1.8 +/- 0.4). Total and free 1,25-(OH)2D3 were still further reduced in patients with mild renal failure. The nephrotic syndrome thus results in mild vitamin D depletion with decreased free 1,25-(OH)2D3 concentrations but generally without secondary hyperparathyroidism.
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PMID:Decreased free 1,25-dihydroxycholecalciferol index in patients with the nephrotic syndrome. 375 49

The cause of the morphological changes and functional defects in the renal tubule seen in patients with severe potassium depletion is unknown. In man and animals potassium status is a major factor regulating ammonia synthesis in the kidney and urinary ammonium excretion. A primary effect of potassium depletion is to cause an increase in ammoniagenesis by the renal tubular cells. It is proposed that the vacuolation of the renal tubular cells and the functional defects of tubular proteinuria, polyuria, resistance to arginine vasopressin, renal resistance to the action of parathyroid hormone, and increased urinary excretion of N-acetyl-beta-glucosaminidase found in potassium depletion are secondary effects caused by high concentrations of ammonia in the renal tubular cells.
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PMID:Increased ammoniagenesis and the renal tubular effects of potassium depletion. 651 81

Dietary phosphorus restriction (PR) prevents uremia in rats with nephrotoxic serum nephritis (NSN). One possible mechanism by which PR could be protective would be through the suppression of parathyroid hormone. To evaluate this possibility two separate protocols were designed. In the first rats were thyroparathyroidectomized (TPTX) before (n = 11) or 5 wk after (n = 7) NSN induction and compared to sham-operated parathyroid intact rats with NSN (n = 12). At the end of the 23-wk study, intact rats were azotemic, plasma creatinine 3.80+/-0.81 mg/100 ml vs. 0.65+/-0.07 for TPTX rats (P < 0.001). During the study 75% of intact rats died of uremia in contrast to none of the TPTX rats (P < 0.001). Renal histological damage was greatly diminished and calcification prevented in TPTX rats. The proteinuria of the heterologous phase was unaffected, but the protein excretion and hypertriglyceridemia (HTG) of the autologous phase were markedly decreased in the TPTX rats. The degree of HTG and proteinuria had a high positive correlation (P < 0.001). Late TPTX also produced significant decreases in proteinuria and HTG regardless of the degree of azotemia, and prevented azotemia if the plasma creatinine at the time of TPTX was </=0.85 mg/100 ml. In additional studies selective parathyroidectomy (PTX) was performed. The adequacy of this procedure was documented by showing a similar fall in plasma Ca and urinary cyclic AMP in PTX animals as found in TPTX animals. However, selective PTX had no effect on proteinuria, histologic damage, or functional deterioration. These studies further showed that early, histologic damage and functional deterioration preceeded renal parenchymal calcification. Because animals were pair fed and both groups were given 1,25-dihydroxycholecalciferol to normalize serum Ca and P levels these studies exclude alterations in plasma Ca and P levels, dietary intake, urinary P excretion, and vitamin D administration in promoting the protective effect of TPTX on renal function. We conclude that TPTX is equally effective in preventing functional deterioration and more effective in reducing proteinuria in NSN than PR. The mechanism of this protective effect remains to be elucidated, since it does not primarily involve either the elimination of parathyroid hormone or the prevention of renal parenchymal calcification.
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PMID:Effect of thyroparathyroidectomy and parathyroidectomy on renal function and the nephrotic syndrome in rat nephrotoxic serum nephritis. 727 65

A laboratory model of renal osteodystrophy was developed in rats by a single injection of glycopeptide isolated from renal cortical tissues of rats according to the method used by Shibata et al. to induce glomerulonephritis. Approximately 60-70 days after injection, severe proteinuria appeared and continued for at least 170 days at a rate of more than 1 g/day. Morphological changes in the kidney were typical of chronic glomerulonephritis. The plasma calcium concentration was lowered transiently by the 96th day after injection, but was restored to the normal range thereafter. Plasma parathyroid hormone levels, however, continued to rise in parallel with the degree of proteinuria. Marked secondary hyperparathyroidism was induced which led to severe bone atrophy. Histological examinations showed a marked increase of resorbing cavities, with a quantitatively larger number of osteoclasts in cortical bone tissues compared with the control animals. No spontaneous remission was observed. It is emphasized that all of the biochemical and morphological changes reported here were induced by a single injection of homologous renal glycopeptide, and they were highly reproducible.
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PMID:Osseous changes and abnormalities of mineral metabolism in rats with glycopeptide-induced nephritis. 737 53

A 6-month protocol of oral pulse calcitriol was used in nine uraemic children (2-14 years old) on dialysis who presented with renal osteodystrophy. Calcitriol was administered twice a week, 4 micrograms per dose for patients over 30 kg and 3 micrograms for patients less than 30 kg. Plasma levels of parathyroid hormone, calcium, phosphorus and alkaline phosphatase were carefully controlled during the study. Parathyroid hormone levels decreased by 68% and 56% by the 2nd and 6th months of treatment in seven patients, while they remained unchanged in two patients with focal segmental glomerulosclerosis and massive proteinuria. Eight hypercalcaemic episodes from 77 determinations were observed, all of them recovered after 1 week of vitamin D withdrawal. We conclude that oral calcitriol pulse therapy is a good alternative for renal osteodystrophy in uraemic children. Careful monitoring of plasma parathyroid hormone and calcium is needed during follow-up when using this approach in paediatric patients.
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PMID:Calcitriol oral pulse therapy in children with renal osteodystrophy. 858 20


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