A lack of coordination in the release of urinary lysosomal and brush border enzymes following renovascular surgery

Pharmacokinetics of gadodiamide injection in patients with severe renal insufficiency and patients undergoing hemodialysis or continuous ambulatory peritoneal dialysis

RATIONALE AND OBJECTIVES

The authors performed this study to evaluate the pharmacokinetics, dialysability, and safety of gadodiamide injection in patients with severely reduced renal function not treated with renal replacement therapy and patients undergoing hemodialysis or continuous ambulatory peritoneal dialysis.

MATERIALS AND METHODS

Twenty-seven patients--nine with severely reduced renal function (glomerular filtration rate, 2-10 mL/min), nine undergoing hemodialysis, and nine undergoing continuous ambulatory peritoneal dialysis--were followed up for 5, 8, and 22 days, respectively, after receiving gadodiamide injection (0.1 mmol per kilogram body weight).

RESULTS

Gadodiamide injection caused no changes in renal function. In patients with severely reduced renal function, the elimination half-life of gadodiamide injection was prolonged (34.3 hours +/- 22.9) compared with data in healthy volunteers (1.3 hours +/- 0.25). An average of 65% of the gadodiamide injected was eliminated during a hemodialysis session. After 22 days of continuous ambulatory peritoneal dialysis, 69% of the total amount of gadodiamide was excreted; this reflects the low peritoneal clearance. In all patients, no metabolism or transmetallation of gadodiamide was found. There were no contrast material-related adverse events.

CONCLUSION

Gadodiamide is dialysable and can safely be used in patients with severely impaired renal function or those undergoing hemodialysis or continuous ambulatory peritoneal dialysis. No precautions to increase the elimination are necessary.

Enzymuria as an index of renal damage in canine leishmaniasis

Urinary enzyme activities of alanine aminopeptidase, gamma-glutamyl transpeptidase, alkaline phosphatase, N-acetyl-beta-D-glucosaminidase and beta-glucuronidase were determined in 15 dogs with leishmaniasis and in a group of eight normal dogs. Serum creatinine and blood urea nitrogen concentrations were also measured and renal histology was examined. All the affected dogs had renal lesions. However, no significant differences in blood urea nitrogen and creatinine concentrations were found between the control group and the affected group. The urinary enzyme activities of gamma-glutamyl transpeptidase (P < 0.01), N-acetyl-beta-D-glucosaminidase (P < 0.01) and beta-glucuronidase (P < 0.05) were significantly higher in the affected dogs. Urinary enzymes therefore seem to be a more sensitive and reliable test for assessing early renal damage in canine leishmaniasis than serum creatinine or blood urea nitrogen concentrations.

Age dependency of infradian rhythms in enzymuria of female volunteers

The enzyme excretion of dipeptidylpeptidase IV (EC 3.4.14.5), gamma-glutamyltransferase (EC 2.3.2.2), and alanine aminopeptidase (EC 3.4.11) was pursued in three different age groups of female volunteers over a period of 70 days. The first group (1-3 years: n = 6) consisted of girls living in a children's home, the second (26-50 years, n = 7) of medical staff and the third (65-87 years, n = 7) of the inhabitants of an old-age home. Subsequent to basic statistics the excretion patterns were analyzed by spectral analysis with the maximum entropy method. The mean values of all enzymes displayed a distinct age-dependency. The highest levels of enzyme excretion were found in the early childhood. In all groups infradian changes of enzyme excretion were detected. In excretion of gamma-glutamyltransferase, longer periods between 12 and 24 days predominated during the early childhood, whereas in the middle, and in particular in the higher age, shorter dominant periods occurred more frequently. The excretion of alanine aminopeptidase displayed a similar tendency. Circaseptan periods (7 +/- 1 days) were rarely observed among the dominant periods of the maximum entropy method spectra. A correlation analysis of the individual excretion patterns revealed that the excretion of all three bush-border enzymes is most tightly correlated in the early childhood (coefficients of correlation up to 0.9). In contrast, the correlation between enzymes and creatinine excretion was low in all age groups.

Effect of sodium valproate on renal cell brush-border enzymes in rats

The effect of sodium valproate (200 mg/kg body weight) on renal cells was investigated during a 10-day trial, by determining the catalytic activities of alanine aminopeptidase, gamma-glutamyltransferase and alkaline phosphatase in the membrane cell brush-border of the renal proximal tubules. Four days after the administration of sodium valproate, a significant increase was observed in the volume of urine (9.2 +/- 4.2 ml/18-h volume; control group, 3.06 +/- 1.8 ml/18-h volume), and in the catalytic activities of gamma-glutamyltransferase (2.69 times that measured in the control group) and alkaline phosphatase (3.02 times that measured in the control group) in urine. After prolonged treatment the urine became alkaline (pH = 10.5 on day 10), thereby excluding alanine aminopeptidase as a useful indicator of renal cell changes following the administration of sodium valproate. The activities of alkaline phosphatase and gamma-glutamyltransferase in isolated vesicles of renal brush-border membrane cells were significantly increased (p < 0.05) and decreased, respectively. On the basis of the results obtained, we believe that the determination of the catalytic activities of gamma-glutamyltransferase and alkaline phosphatase in urine might prove useful for the follow-up of the renal cell state during therapy with sodium valproate.

Excretion of urinary enzymes after extracorporeal shock wave lithotripsy: a critical reevaluation

The excretion of the urinary enzymes alanine aminopeptidase, alkaline phosphatase, gamma-glutamyl-transferase and N-acetyl-beta-D-glucosaminidase, and the 99mtechnetium-diethylenetriaminepentaacetic acid isotope clearance were studied in 35 patients treated with extracorporeal shock wave lithotripsy (ESWL*). Enzyme measurements were made before and consecutively on days 1, 2 and 5, and at 3 months after treatment. A control group investigated at the same intervals was included. Posttreatment enzyme values were not significantly different from those before treatment except for alkaline phosphatase on day 1 after ESWL. Some individuals had short-term increases of enzymuria that were greater than biological variations in the control group. The transient changes of enzymuria after ESWL had no predictive value for kidney function, since no decreased renal function was observed in individual patients with high enzyme excretions after ESWL.