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A Westhoff

Publications and source records attributed to A Westhoff.

15 recordsLinked to original sources
PubMed1998

Long-term experience with an ultrapure individual dialysis fluid with a batch type machine.

BACKGROUND: This paper discusses long-term experience with a specific type of dialysis equipment which has been used more than 15 years without variation. The system was designed to allow easy individualization of dialysis fluid composition and to deliver dialysate of the highest hygienic quality. METHODS: Data from 399 patients covering the period from 1971 onwards were analysed retrospectively. Survival probabilities were estimated by the Kaplan-Meier method and the median number of days in hospital was calculated. Additional data collected from patient subgroups included serum albumin level, erythropoietin requirement and antihypertensive treatments. Kt/V and PCR from one subgroup were computed using the formulae of Daugirdas and Depner. RESULTS: The estimated survival probability after 5 years for all patients was 59.1% (95% CI: 52.6-65.6%). The main risk factors from the available covariables were age and IDDM. The cumulative incidence of carpal tunnel syndrome after 10 years of dialysis was estimated as 7% (95% CI: 0-14%). Data from the subgroups revealed that 82% of the patients had serum albumin levels >4.0 g/dl, 65% of the patients received no antihypertensive drugs and 39% received erythropoietin (37 +/- 28 units/kg bw/week) to correct dialysis anaemia (haemoglobin level = 98 +/- 8 g/l). Average Kt/V was 1.21 +/- 0.17, PCR was 1.10 +/- 0.22 g/kg/day. CONCLUSIONS: The setup described permits individualized therapy of high quality. The high serum albumin values and our very low incidence of carpal tunnel syndrome underline the importance of water and dialysate quality.

Adult↗
PubMed1998

[Measurement of glomerular filtration rate (GFR) after administration of iodine contrast medium with the Renalyzer PRX90 in healthy cats and cats with kidney diseases].

In the present study, the measurement of the glomerular filtration rate (GFR) in the cat with the aid of an iodine contrast medium clearance with the renalyzer PRX90 is introduced. Investigations on the accuracy of measurement showed that even repeated measurement of plasma samples after two days of storage at room temperature yielded reproducible clearance results. Also, partial dilution of the plasma sample (2 ml with 1 ml Aqua bidest.) to reduce the volume of blood withdrawn still produced reliable results. Further dilution of the plasma volume (1 ml with 2 ml Aqua bidest.) however did not allow for accurate measurements. A total of 59 cats of different age and sex were included in the study. 31 cats had healthy kidneys with urea and creatinine values within the reference range, unchanged urine findings and physiologic urine protein patterns (SDS-PAGE). These cats served as reference group. The GFR reference value ascertained for these animals was 2.1 ml/min/kg BW (mean = 3.45 ml/min/kg with s = +/- 1.0 ml/min/kg). 28 cats had elevated values of urea and creatinine in the blood, as well as partially changed urine findings. For further diagnosis of renal disease, separation of urine proteins was done with the SDS-PAGE in the PhastSystem, which in all cases yielded a pathologic urine protein pattern. In 11 cases the renal disease could be further confirmed by histological investigation. GFR in these patients was clearly lowered compared with healthy cats, with measured values between 0 and 1.8 ml/min/kg. It can be concluded that the renalyzer allows reliable determination of the GFR also in the cat. To what extent measurement of the GFR is also helpful to diagnose nephropathies in the stage of compensation needs to be further investigated. In cats with high grade uremia and a GFR below 1 ml/min however, an exact calculation is not possible, since the accuracy of measurement within this range is inadequate. Thus, in severe disease no correct assessment is possible, and no statement concerning prognosis can be made.

Animals↗
PubMed1997

[Qualitative and quantitative kidney function testing in dogs using MAG3 clearance].

In the presented study 99mTc-MAG3 clearance measurements were undertaken in 14 dogs during renal scintigraphic examination. Of these dogs, 10 showed no renal impairment, the other 4 exhibited clinically manifested nephropathy. It was the aim of these examinations to determine if this type of clearance measurement that is routinely used in human medicine is suitable for diagnosis of canine nephropathy. An algorithm for the calculation of the MAG3-Clearance developed for humans was modified. The clearance measurement can be performed during the renal scintigraphic procedure without any difficulties. In the group of dogs with no renal impairment the clearance values ranged between 6.4 and 8.0 ml/min/kg, whereas in the group of patients exhibiting nephropathies the values ranged between 2.0 and 2.7 ml/min/kg. The suitability of the method for its use in dogs needs to be confirmed with higher patient numbers. In addition, further studies are necessary to precisely assess the correlation between measured clearance values and effective renal plasma flow in dogs.

Animals↗
PubMed1996

[Scintigraphic study for the diagnosis of portosystemic shunts in dogs].

The technique of scintigraphy of the liver is presented by two case examples of dogs with portosystemic shunts. 99mtechnetium-pertechnetate was used as a marker. Comparison of velocity and height of the activity reaching liver and heart and lung allows a statement about the existence of a portosystemic shunt.

Animals↗
PubMed1996

[Kidney scintigraphy in dogs and cats using 99mTc-MAG3].

Renal scanning is one of the imaging techniques used to investigate the upper urinary tract. In the present examination, the principles of performing renal scanning in the dog and car are described. Eleven animals with healthy kidneys (six dogs and five cats) were included in the study for the determination of normal scintigraphic findings as well as eight animals (seven dogs and one cat) with renal damage. The following nephropathies were investigated scintigraphically: nephrolithiasis, hydronephrosis, polycystic renal degeneration, renal aplasia, renal hypoplasia, obstruction of the ureter and renal trauma. Renal scanning proved to be easy to perform with acceptable effort in the dog and cat. It allows the simultaneous assessment of renal function on both sides during the phases of renal perfusion and tubular se- and excretion and represents a valuable adjunct to the morphologically orientated radio- and sonography. The nephrogram curves are comparable to those found in man, although the time until reaching the maximum of the curves and elimination half times are shorter. Also, the sequential scintigrams can be divided into the corresponding phases as in man. Through permanent technical development, today there are gamma processors at disposal that allow a faster, comprehensive and sophisticated evaluation. In the present investigation, this was demonstrated by a comparison of two different calculators. However, due to the financial and technical expenditures and the special radiological safety precautions required, renal scanning will be a technique reserved to larger clinics.

Animals↗
PubMed1996

[Validity of diagnostic methods for kidney function tests in the cat].

The diagnosis of kidney disease is difficult in the stage of compensation and impossible based solely on the routinely performed laboratory tests on blood and urine. For this reason, more sensitive methods are required. In the present study, three special techniques are compared with regard to their validity in the early diagnosis of kidney disease in the cat: 1. the molecular-weight related separation of urine proteins with the sodium-dodecyl-sulfate-polyacrylamide-gradient gel electrophoresis (SDS-page) in the PhastSystem, 2. measurement of the glomerular filtration rate (GFR) with the renalyzer PRX90 using an iodine containing contrast medium and 3. kidney scintigraphy. The results of this comparison demonstrate that these procedures are important adjuncts to common laboratory investigations in the testing of renal function. The SDS-page allows an early qualitative assessment on alterations of specific functional compartments of the kidney. However, it is not possible with this method alone to evaluate the degree of renal disturbance and it does not give information concerning the severity of renal functional impairment. Measurement of the GFR is also a valuable procedure which gives a quantitative result on the global renal function within a few hours. It is of special importance when subclinically disturbed kidney function is present. In the cat however it is until now not possible to give a correct prognosis in high grade nephropathies. Only scintigraphy allows unilateral assessment of renal function, which is most important in cats with morphologically altered kidneys, such as kidney cysts, hydronephrosis or tumours.

Animals↗
PubMed1994

Renin secretion and captopril stimulation in hypertensive renal transplant recipients.

Basal renin secretion and the diagnostic value of a captopril stimulation (captopril test) in identifying renovascular hypertension secondary to transplant renal artery stenosis was assessed in 69 patients with hypertension after renal transplantation. An increase of plasma renin activity of 260% 1 h after captopril was considered as a positive result, assuming renovascular hypertension. Six of 69 patients had a positive captopril test, of these patients 5 had transplant renal artery stenosis. These patients were treated with percutaneous transluminal angioplasty (PTA) or surgery. Based on angiographic results and blood pressure response after PTA or surgery the captopril test showed a sensitivity of 100% and a specificity of 92% in the identification of hemodynamically significant stenosis of the transplant artery. Therefore, the captopril test provides a suitable screening instrument for the differential diagnosis of hypertension following renal transplantation.

Adult↗
PubMed1992

[Pneumocystis carinii pneumonia: a life threatening complication after kidney transplantation].

Aggressive immunosuppression in kidney transplantation increases the risk of opportunistic infections. We report ten cases of pneumocystis carinii pneumonia in a group of 420 kidney recipients (2.1%). All patients showed a severe--hyperacute--course of the infection. One patient required mechanical ventilation. In all cases the diagnosis could be established applying fibreoptic bronchoscopy with lavage and partly using transbronchial biopsy. The therapy consisted of intravenous cotrimoxazole and inhalation of pentamidine. All patients survived even after severe course of the disease. Graft explantation for saving patients was not necessary.

Administration, Inhalation↗