Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0034186 (pyelonephritis)
 6,144 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The purpose of the study was assessment of gentamicin nephrotoxicity with reference to proximal tubule function and glomerular filtration. The study was carried out in 20 patients with nephrolithiasis and chronic pyelonephritis, and 33 patients with respiratory and bile tract infections treated with gentamicin in doses of 2-3 mg/kg/2 h. In 3 patients with nephrolithiasis and chronic pyelonephritis signs of increased nephrotoxicity of gentamicin (according to Schentag criteria) were found. Similar signs were demonstrated in 3 patients with non-urinary tract infections. The abnormalities included increased excretion of low-molecular protein and beta-2-microglobulin (B2m), reduction of B2m reabsorption and lower glomerular filtration. Beta-2-microglobulinuria increase precede by 4-5 days the fall of the glomerular filtration rate which suggests that beta-2-microglobulinuria assessment is an early sign of gentamicin neurotoxicity.
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PMID:[Nephrotoxic effect of gentamicin on the function of the proximal tubules of the nephron and glomerular filtration]. 129 38

24 h urinary excretion of beta-microglobulin (beta 2M) and Tamm-Horsfall protein (THP) before and after administration 40 ml of 75% Uropoline were assessed, as a specific markers of proximal and distal tubular dysfunction respectively. 22 patients without renal diseases and hypertension (C), 22 hypertensive patients (HP), 14 patients with renal stone disease (RSD) and 16 patients with pyelonephritis (PN) were examined. Administration of Uropoline did not change beta 2M and THP urinary excretion in C, but increased beta 2M excretion in HP and decreased THP urinary excretion in patients with RSD. It is concluded, that Uropoline shows a noxious effect on the proximal tubule in HP and on the distal tubule in patients with RSD.
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PMID:[Estimation of renal tubular function after uropoline administration in certain disease states]. 130 67

During the peri- and early postnatal period, nephrogenesis is completed and kidney growth is accomplished both by cellular proliferation and enlargement. The number of nephrons in a given species is predetermined, whereas cellular growth can be influenced by environmental factors in an age-dependent manner. Unilateral nephrectomy or a high-protein diet stimulates renal growth more in the young than in the adult. Conversely, pyelonephritis inhibits renal growth in infancy but not in adulthood. The relative importance of hyperplasia and hypertrophy for renal growth also changes with renal maturation. The mechanisms behind these developmental changes in regulation of renal growth are largely unknown, but age-dependent changes in the expression of several proto-oncogene products have been demonstrated. These include growth factor receptors as well as components of the intracellular system that transfers the signal from an activated growth factor receptor to the cell nucleus. Studies on rat proximal tubule cells in primary culture might be of great value in expanding our knowledge of growth regulation in the developing kidney. Such studies have already shown that under identical environmental conditions the basal proliferative rate is age dependent, that the proliferative response to growth stimulation changes postnatally, and that this is associated with changes of both the response of the Na+/H(+)-exchanger and the expression of the c-fos proto-oncogene.
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PMID:Renal growth in infancy and childhood--experimental studies of regulatory mechanisms. 191 Nov 19

The purpose of the study was assessment of the usefulness of renal excretion of beta 2-microglobulin (B2M) in the differential diagnosis of infections situated in the upper and lower parts of the urinary tract. The study was carried out in 15 patients with infections of the upper part of the urinary tract (acute pyelonephritis), 10 patients with infections of the lower part of this tract (cystitis), and 50 healthy controls. In all studied subjects the B2M concentration was assessed in the serum and urine by radioimmunoassay (Pharmacia B2-micro RIO 100, Uppsala, Sweden). From the obtained data B2M clearance (CB2M) and tubular reabsorption of B2M (TRB2M) were calculated. In patients with upper urinary tract infections a statistically significantly greater urinary B2M excretion, significantly higher CB2M value, and significantly decreased TRB2M were found as compared to patients with lower urinary tract infections. The obtained data suggest presence of dysfunction of the proximal tubule in upper urinary tract infections and demonstrate the usefulness of beta 2-microglobulinuria assessment in the differential diagnosis of upper and lower urinary tract infections.
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PMID:[Usefulness of beta-2-microglobulin determination in the differential diagnosis of infections in the upper and lower parts of the urinary tract]. 219 74

Accelerated rates of ammonia production by the renal proximal tubule constitute an important adaptation to chronic renal injury. Although serving to maintain net acid excretion, this augmented production of ammonia per nephron results in increased renal cortical levels of ammonia and contributes to progressive renal injury. Ammonia fosters progressive injury via its ability to modify the third component of complement and initiate alternative complement pathway activity. This interaction of ammonia with complement incites inflammation in models of nonimmune chronic renal disease in the rat and may contribute to tissue injury in pyelonephritis involving urease-positive organisms. The long recognized in vivo association between increased renal ammoniagenesis, renal growth, and progressive injury in several models of renal disease has been advanced by the recent demonstration of ammonia as a direct stimulus to growth of renal tubular epithelium in culture. Additionally, evidence from studies of acute ischemic renal injury suggests a contributory role for ammonia in mediating tissue injury in this model. Elevated renal levels of ammonia, therefore, contribute to tubulointerstitial injury primarily through the proinflammatory and growth-promoting properties of ammonia.
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PMID:Role of ammonia in tubulointerstitial injury. 228 94

In an animal model of chronic nephropathy a large proportion of the apparently normal glomeruli have been shown to be small and without connection to a proximal tubule. The present study examines the degree to which atubular glomeruli are also present in human renal disease. Eleven patients with chronic pyelonephritis (CP) and seven controls were investigated. The number of glomeruli connected to a normal proximal tubule was determined in serial sections and the volumes of individual glomeruli estimated with stereological methods. Only glomeruli with little or no sclerosis were investigated. The volume fractions of proximal tubules and interstitial tissue were estimated using point counting. The results showed that 50% of glomeruli in the CP group were connected to a normal proximal tubule, whereas 35% of the glomeruli were without any recognizable connection to a proximal tubule (atubular glomeruli). The remaining 15% were connected to an atrophic tubule. The mean volume of the glomeruli without a connection to a normal proximal tubule was only half that of glomeruli with a normal proximal tubule. No significant difference was found between the mean glomerular volume in the two groups, but the intraindividual variation of glomerular volumes was larger in the CP group. A significant negative correlation was found in the CP group between the percentage of glomeruli without connection to a normal proximal tubule and the volume fraction of proximal tubules. A significant positive correlation was found between the percentage of glomeruli that were not connected to a normal proximal tubule and the volume fraction of the interstitial tissue. This study shows that atubular glomeruli, which only can be identified in serial sections, constitute a large proportion of glomeruli in chronic pyelonephritis. Their existence could be a major reason for the irreversibility of nonglomerular chronic renal diseases.
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PMID:Atubular glomeruli in patients with chronic pyelonephritis. 233 70

The aim of the present work is to evaluate the function of the proximal tubule in patients with active metabolic stone disease (a.m.s.d.), recognizing the urinary excretion of beta-2-microglobulin (B2-M) as a sensitive marker of that function. The investigated group included 30 patients with a.m.s.d. accompanied by chronic pyelonephritis (CP) and 31 patients with a.m.s.d. without CP. The serum and urinary B2-M concentrations were estimated by radioimmunoassay. The clearance of B2-M (CB2-M) and the tubular reabsorption of B2-M (TRB2-M) were estimated. Patients with a.m.s.d. and CP showed an increased excretion of B2-M, significantly higher values of CB2-M and a significantly lower TRB2-M. The results indicate that the proximal tubular dysfunction in the group of patients with a.m.s.d. is a result of a chronic inflammatory process in the urinary tract.
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PMID:Urinary excretion of beta-2-microglobulin in patients with active metabolic stone disease. 269 91

Aminoglycosides have a low molecular weight and bind weakly to proteins. They are easily filtered through the glomeruli, bind to phospholipid receptors located on the brush border of proximal tubule cells, and penetrate within the cells by endocytosis. Aminoglycosides decrease lysosomal A and C phospholipase and sphingomyelinase activities. This impairs the degradation of phospholipids, with formation of abnormal intralysosomal structures called myeloid bodies as a result. These myeloid bodies are gradually eliminated from the cells into the lumen of the tubule and excreted in the urine. We studied the urinary excretion of phospholipids following 1, 3, 5 and 10 days of treatment with gentamicin (3 mg/kg/day) or tobramycin (3 mg/kg/day) in patients with acute pyelonephritis. Infection-free, non-treated subjects were used as controls. Patients with a urinary tract infection treated by a quinolone made up a third group. Urinary N-acetyl-beta-D-glucosaminidase (NAG), an indicator of epithelial necrosis, was also evaluated. Results were expressed per ml urine, per mg creatinine and per 24 hours. Only the results expressed per mg creatinine appeared valid. No significant increase in serum creatinine or urinary NAG was found in patients under gentamicin. In the patients with a urinary tract infection not treated with an aminoglycoside, urinary phospholipid excretion on D1 was decreased as compared to controls (p less than 0.01). Urinary phospholipid excretion was never found to be increased in patients under aminoglycosides. No significant difference was found between males and females. Mistaken interpretations occurred if urinary excretion of phospholipids or NAG was not expressed per mg creatinine.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Urinary excretion of phospholipids: index of aminoglycoside nephrotoxicity]. 353 46

In contrast to healthy persons, microvillous antigens of the proximal tubule were excreted at an increased rate in patients with kidney diseases as could be shown using specific antisera against brush border (BB) fragments (tissue-proteinuria, histuria). These urinary membrane components were immunologically completely identical with those antigens prepared from isolated kidney cell membranes. A glycoprotein of 240 000 dalton, containing mannose and N-acetylglucosamine was identified as a major immunoreactive constituent of the brush border surface and found to be part of a multienzyme complex. BB-antigens were excreted in urine of patients with glomerulonephritis, hypertension, pyelonephritis, multiple myeloma, after operations, after kidney transplantation, under cytostatic treatment, and after administration of radiopaque agents. Histuria of BB-antigens was significantly higher in patients with multiple myeloma and Bence-Jones-proteinuria compared to those patients where no Bence-Jones L-chains in urine became apparent. Selective kidney angiography and intravenous urography caused a significantly higher output of BB-antigens as compared to the control period (2 p less than 0,005). In a volunteer model, on the basis of BB-histuria, a different nephrotoxic potency of cephalosporins and aminoglycosides arose. In addition, beside soluble BB-antigens, also high molecular weight membrane vesicles were discovered in urine of patients after cytostatic treatment (cis-platinum), after x-ray contrast media, and after kidney transplantation. Both, soluble as well as supramolecular membrane vesicles were isolated from urine applying immunospecific affinity chromatography (anti-BS-agarose beads). Labeled antisera directed against the vesicle material of urine revealed a specific immunofluorescence of cortical tubule only.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Immunodiagnosis of kidney tubular cell injuries using specific anti-membrane antibodies]. 638 21

The study aimed at evaluating the proximal tubule function in patients with active metabolic urolithiasis with the assay of beta 2-microglobulin in the urine. The studies involved 30 patients with urolithiasis associated with chronic pyelonephritis and 31 patients with urolithiasis without pyelonephritis. Fifty healthy individuals served as a control group. Serum and urine beta 2-microglobulin concentrations were assayed with radioimmunological technique in all persons. Clearance of this microglobulin and tubular reabsorption were calculated. It was found that beta 2-microglobulin excretion with the urine is significantly higher in patients with metabolically active urolithiasis accompanied by the chronic pyelonephritis. beta 2-microglobulin clearance was significantly higher and tubular reabsorption significantly lower than those in patients without pyelonephritis and in control group. These finding suggest a dysfunction of the proximal tubule in patients with urolithiasis produced by the chronic inflammatory process in the urinary system. Negative correlation between blood serum beta 2-microglobulin levels and creatinine clearance was shown. Therefore, serum beta 2-microglobulin concentrations may be of value in evaluation of the glomerular filtration rate.
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PMID:[Usefulness of determining beta-2-microglobulin in serum and urine in patients with metabolically active kidney calculi and healthy individuals]. 817 Aug 11


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