Clinical aspects of renal transplantation in polycystic kidney disease.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) as a systemic disorder represents a special subgroup among patients with end-stage renal disease (ESRD). The different organ manifestations are potential risk factors for cardiovascular events or infections in the course after renal transplantation. Therefore, a long-term evaluation of ADPKD patients and of a control group was done. PATIENTS AND METHODS: 80 ADPKD patients were compared with 88 non-diabetic patients in a retrospective follow-up after renal transplantation. Patient and graft survival (1, 5 and 10 years after transplantation) as well as complications such as infections and cardiovascular events were evaluated. RESULTS: A comparable overall transplant (1 year, 5 years, 10 years: 83%, 73%, 67% ADPKD vs. 84%, 70%, 51% controls) and patient survival rate (1 year, 5 years, 10 years: 96%, 84%, 73% ADPKD vs. 91%, 79%, 58% controls) was found in both groups. Infectious complications with the exception of urinary tract infections (UTIs: ADPKD 42.5% vs. 26%) were diagnosed in similar frequency in the graft recipients. ADPKD patients were significantly more affected by UTIs than their control group (p < 0.05) and tended to suffer more often from lethal infections (ADPKD 7 vs. controls 3), but without statistical significance. Cardiovascular events were not observed to be significantly different between both groups (ADPKD 3 vs. controls 4). An obvious difference was found in patient (p < 0.01) and transplant survival rates (p < 0.05) of male and female ADPKD patients. The female group showed a significantly better outcome. CONCLUSIONS: The overall patient and graft survival rates did not differ between the ADPKD and control groups. The better outcome of female ADPKD graft recipients compared to the male group may be related to a gender-dependent disease severity, possibly due to hormonal effects. As UTIs and lethal septicemia were the leading complications in ADPKD patients, a careful monitoring for infections is important in the post-transplant follow-up.

Lower serum high-density lipoprotein-cholesterol concentration in patients undergoing maintenance hemodialysis with acetate than with bicarbonate.

The authors studied the effect of dialysate buffer composition on the serum lipid values in male patients undergoing maintenance hemodialysis. Twenty patients on acetate and 21 patients on bicarbonate hemodialysis were investigated. The serum concentrations of high-density lipoprotein (HDL)-, HDL2- and HDL3-cholesterol were significantly lower in patients on acetate than in those on bicarbonate dialysis. The results of this study suggest possible adverse effects of acetate hemodialysis on serum HDL-cholesterol compared with bicarbonate hemodialysis. Other possibly contributory factors such as age and time on dialysis could be excluded. However, a possible role of differences in drug therapy between acetate- and bicarbonate-treated dialysis patients could not be entirely excluded.

Practical approach for determining glomerular filtration rate by single-injection inulin clearance.

We compared the glomerular filtration rate as measured by a single-injection inulin clearance with that measured by a standard isotope method with 99mTc-labeled diethylenetriaminopentaacetic acid in 21 subjects with glomerular filtration rates greater than 35 mL/min. After a bolus injection of 5 g of inulin, blood samples were taken 20, 45, 90, 120, 145, 180, and 240 min afterwards. Inulin was measured by optimized chemical or enzymatic methods of high analytical sensitivity to determine inulin at low concentrations. We used the one-compartment model and inulin concentrations measured at two sampling times to calculate the glomerular filtration rate from the data of the disappearance curve of inulin. Inulin concentrations at 20 and 240 min after injection of the inulin bolus were suited to estimate glomerular filtration rate by this procedure, resulting in values (y) comparable with those obtained by isotope technique (x). The relationship to the isotope technique was characterized by the equation y = +4.80 mL/min + 0.92x (r = 0.97). The single-injection inulin clearance determination can detect a decrease of glomerular filtration rate at the beginning of kidney damage, given that our study included subjects with glomerular filtration rates greater than 35 mL/min. We conclude that the glomerular filtration rate can be determined by analyzing only two blood samples after a bolus injection of inulin.

[Evaluation of methods for the analysis of low insulin concentrations in serum]. / Evaluierungsuntersuchungen von Methoden zur Bestimmung neidriger Inulinkonzentrationen im Serum.

Three methods of the determination of insulin in serum were optimized in order to determine low concentrations of this analyte reliably (Method I: enzymatic after acidic hydrolysis of inulin; Method II: by anthrone/sulfuric acid reagent; Method III: by cysteine/tryptophan reagent). The interfering reaction of glucose in the methods I and II was avoided by the preincubation of samples with glucose oxidase/catalase reagent. The detection limit of all three methods was below 5 mg/l and the within-run precision amounted to values below 5%. Method I and II gave identical results. In comparison with these two methods, method III resulted in inulin values by about 8% lower, because inulin, depending on the lot used, contained alkali-labile fractions which were destroyed during the sample preparation. Method II is recommended for routine measurements because of its an analytical reliability and its cost-effectiveness.

[The syndrome of retrograde venous arterialization following arteriovenous vascular anastomoses for hemodialysis]. / Syndrom der retrograden venösen Arterialisation nach arteriovenösen Gefässanschlüssen für die Hämodialyse.

In 9 patients with arterio-venous side-to-end anastomosis on the forearm as vascular access for chronic hemodialysis an uniform symptom complex was observed: retrograde flow of the ectatic vein into the periphery, swelling and pain in this area, partly with trophic skin disorders on the hand. After occlusion of the arterio-venous anastomosis these symptoms could reversed completely with exception of venous dilation.

[Factors influencing the duration of function of arteriovenous vascular anastomoses in hemodialysis]. / Einflüsse auf die Funktionsdauer arterio-venöser Gefässanschlüsse für die Hämodialyse.

The function of an arterio-venous vascular access is influenced by vascular material, hemodynamics, blood coagulation and technique and number of punctures. By careful intraoperative handling, optimal postoperative care and treatment of the vascular access during and after hemodialysis the functional duration may be influenced effectively. The technique of puncture, the puncture cannula and the skill of the "puncture" are of great importance.

[The low molecular weight proteins ribonuclease, beta 2 microglobulin and lysozyme in the serum and urine of patients with chronic kidney diseases]. / Die niedermolekularen Proteine Ribonuclease, beta 2-Mikroglobulin und Lysozym im Serum und Urin von Patienten mit chronischen Nierenerkrankungen.

The diagnostical relevance of the low-molecular proteins ribonuclease, beta 2-microglobulin and lysozyme in serum and urine to detect a reduced glomerular filtration rate was examined in 52 patients with chronic renal diseases. The radioisotope clearance using 99mTc-DTPA was the base reference; the reference values of the low-molecular proteins were estimated in a control group. Ribonuclease was increased above the upper borderline value, if the glomerular filtration rate was lower than 1.24 ml s-1. Creatinine, beta 2-microglobulin and lysozyme remain yet in part in the normal range. The estimation of the ribonuclease in serum is suitable to detect an impaired glomerular filtration rate if the creatinine value is still not increased. Thereby, the diagnostics in renal diseases may be improved in the creatinine-blind area.

Changed composition of high-density lipoprotein subclasses HDL2 and HDL3 after renal transplantation.

The concentrations of cholesterol in the high density lipoprotein (HDL) fraction and the HDL2 and HDL3 subclasses were compared in 333 male renal transplant recipients, 36 male patients on maintenance hemodialysis, and 43 healthy men. The subclasses were separated by a precipitation method using polyethylene glycol 6000 and dextran sulphate. In hemodialyzed patients, total HDL cholesterol and both subclasses were reduced. In renal transplant recipients, both total HDL cholesterol and HDL2 were normal, whereas HDL3 remained reduced, analogous to hemodialyzed patients. It can be concluded that a successful renal transplantation has a beneficial effect on HDL metabolism and thus on the development of atherosclerosis.

[Subclavian Scribner shunt for hemodialysis]. / Subclavialer Scribner-Shunt für die Hämodialyse.

In two dialysis patients with absolute indication to a temporary Scribner shunt and lacking typical access possibilities (limb, leg) an effective vascular access has been created between the Arteria and Vena acromio-clavicularis. Because of the short trunk of the A. acromio-clavicularis a lengthening by a vein transplant was necessary.

[Indications for the Scribner shunt in hemodialysis]. / Indikationen zum Scribner-Shunt für die Hämodialyse.

The indication to a Scribner shunt as vascular access for hemodialysis has been reduced significantly by the use of central-venous catheters and creation of subcutaneous access methods. In 13 patients suffering from septic complications of the central-venous vascular access catheters a Scribner shunt was created for continuation of hemodialysis. After removal of infected catheters and specific antibiotic therapy the sepsis could be controlled in 12 patients within 4-18 days.

[Use of formaldehyde-preserved, silicone-coated inner surface and form-fixed bovine blood vessels as vascular transplants]. / Untersuchungen zum Einsatz formaldehydkonservierter, innenflächensilikonierter und formfixierter boviner Gefässe als Gefässtransplantate.

A total of 114 vascular transplants of formaldehyde-preserved, form-fixed bovine vessels with silicone-coated inner surface were implanted to 113 dialysis patients and to one patient with asthma bronchiale. They were used as arteriovenous bridging grafts for punctures or parts of them and as arterial bridging grafts for repair. Included were A. glutealis in 43 instances as well as A. thoracica interna, V. glutealis and V. thoracica interna in 18 instances, and A. sacralis in 53 cases. Low early-thrombosis rates were recorded from all transplants. Transplants of A. glutealis and A. thoracica interna quite often exhibited spontaneous aneurysmatic enlargement in response to repeated puncturing. Fewer complications were recordable from transplants of A. glutealis, V. thoracica interna and A. sacralis.

[Straight upper arm arteriovenous implants of allogenic vascular transplant material in various hemodynamic conditions]. / Gerade arterio-venöse Interponate am Oberarm aus allogenem Gefässersatzmaterial unter verschiedenen hämodynamischen Bedingungen.

Studies were conducted into the effects of various forms of flow reduction upon both pressure in shunt and functional properties of 134 arteriovenous bridging grafts on the upper arm for haemodialysis of deantigenised, form-fixed, preserved segments of varicose veins with silicone-coated inner surfaces. Strongest pressure reduction and best clinical results were obtained from composite grafts with a short, narrow segment on the inflow side.

Diagnostic significance of different urinary enzymes in patients suffering from chronic renal diseases.

The urinary enzymes alanine aminopeptidase (EC 3.4.11.2), alkaline phosphatase (EC 3.1.3.1), gamma-glutamyltransferase (EC 2.3.2.2), N-acetyl-beta-D-glucosaminidase (EC 3.2.1.30), and ribonuclease (EC 3.1.4.22) were measured in 66 healthy persons and 52 patients suffering from chronic renal diseases (pyelonephritis, glomerulonephritis). The residual renal function of patients characterized by 99mTc-diethylenetriaminopentaacetate isotope clearance was only moderately reduced. Except for gamma-glutamyltransferase, patients generally showed increased urinary enzyme excretions. N-Acetyl-beta-D-glucosaminidase was more sensitive to detect renal dysfunction than the other enzymes and the conventional parameters serum creatinine, total protein excretion, and the measurement of glomerular filtration rate. The determination of this enzyme can be recommended as a suitable diagnostic parameter in nephrology.

Diagnostic value of low-molecular mass proteins in serum for the detection of reduced glomerular filtration rate.

The diagnostic value of the low-molecular mass proteins ribonuclease, beta 2-microglobulin, and lysozyme in serum for the detection of reduced glomerular filtration rates was evaluated. The values of these proteins and of serum creatinine investigated in 52 patients suffering from chronic renal diseases were plotted against 99m-Tc-diethylenetriaminopentaacetate clearance as an indicator of glomerular filtration rate. Log-transformed data showed a good fit of linearity. Considering the 95% confidence limits of the regression equations, ribonuclease increased above the normal range when the glomerular filtration rate was lower than 1.24 ml/s whereas the other analytes partly remained within their normal limits. Out of those 18 patients with glomerular filtration rates lower than 1.24 ml/s, all patients showed elevated ribonuclease levels. beta 2-Microglobulin, creatinine, and lysozyme were increased in 17, 14, and 12 cases, respectively. Ribonuclease and beta 2-microglobulin showed similar results when other diagnostic criteria (specificity, efficiency and predictive values) were taken into account. We recommend ribonuclease determination in serum for the detection of reduced glomerular filtration rate in the normal range of creatinine. The test is diagnostically powerful, cheap and easy to perform.