Medication compliance after renal transplantation

Noncompliance is known to be an important cause of late graft failure after renal transplantation. We investigated prospectively the degree of compliance with immunosuppressive and antihypertensive drugs during the first year after renal transplantation by monthly pill counts. In addition, we examined whether noncompliance was related to a number of demographic and clinical variables or to the occurrence of rejections. The study population consisted of 127 patients who were involved in a randomized trial comparing cyclosporine monotherapy with azathioprine-prednisone treatment. Average compliance rates approximated 100%, although considerable variability within and between subjects was observed. Using an arbitrary limit to classify patients as compliers or noncompliers, the following frequencies of noncompliance were observed during the study year: cyclosporine, 23%; azathioprine, 13%; prednisone, 23%; atenolol, 36%; and nifedipine, 32%. Average compliance scores for all immunosuppressive drugs were superior to those of antihypertensive medication (P < 0.001). Except for a better compliance for prednisone in men as compared with women, we found no consistent relationship between compliance on the one hand and several demographic variables, graft function, or quality of life on the other hand. Patients who developed one or more acute rejection episodes showed a higher degree of undercompliance, especially for prednisone, than patients without rejections (P < 0.01). Following the occurrence of a rejection episode, compliance scores improved significantly. Keeping in mind the limitations of the pill count method, we conclude that noncompliance with immunosuppressive drugs is not a huge problem during the first year after renal transplantation. However, it is likely that noncompliance contributes to a certain number of acute rejection episodes.

Soluble tumor necrosis factor-receptors are not a useful marker of acute allograft rejection: a study in patients with renal or cardiac allografts

In this study, we investigated soluble tumor necrosis factor receptor (sTNF-R) levels in plasma of patients with either a kidney or cardiac allograft when clinical suspicion of acute rejection was raised. In plasma of patients with acute renal graft rejection, the sTNF-R levels were strongly enhanced (20-150 ng/ml) as compared to plasma of patients with stable renal function. Following successful treatment of the rejection, a gradual decline in sTNF-R levels occurred with improving renal function, and an inverse correlation between creatinine clearance and sTNF-R was found. To determine whether the increase was caused by an accumulation of constitutively released sTNF-R and lack of clearance by the kidney, or whether the immunological process of the rejection caused the enhancement, we measured sTNF-R in patients suffering from acute cardiac graft rejection but with predominantly stable kidney function. Rejection of a cardiac graft did not lead to a significant enhancement of sTNF-R levels. However, treatment with ATG or OKT3 did cause enhanced sTNF-R levels, followed by a decline that reached starting values after 7 days. These results provide evidence that the immune reaction that occurs during rejection of a graft does not per se induce discernible changes in sTNF-R levels, whereas that induced by ATG or OKT3 does. Thus, sTNF-R levels are not reliable marker in transplant recipient monitoring.

Echo-Doppler diagnosis of renal allograft artery stenosis

For the diagnosis of allograft artery stenosis in recipients of a renal transplant with hypertension a noninvasive investigation such as echo-Doppler is preferable to invasive methods such as angiography. Therefore we analyzed our experience with echo-Doppler diagnosis of renal allograft artery stenosis. In 131 renal transplant recipients with hypertension echo-Doppler examinations were performed. During the examinations several features indicative of stenosis were measured, and intrarenal Doppler spectra were quantitatively analyzed with a user-written program. Four patients showed signs of iliac artery stenosis. In 12 patients a renal allograft artery stenosis was suspected on echo-Doppler examination. In 8 of these 12 patients angiography was performed. All these showed a stenosis, 6 of which had more than > 75% stenosis. In 8 patients with normal echo-Doppler findings angiography was performed because of highly suggestive clinical signs of stenosis. In 7 of these no stenosis was found and in one a 50% stenosis was found. Comparison of quantitative Doppler spectrum features from patients with (n = 6) and without severe (> 75%) stenosis on angiography (n = 10) showed significant differences in several Doppler parameters. Subsequently an analysis of the best differentiation between these to groups on the basis of quantitative Doppler criteria was performed. In conclusion, echo-Doppler examinations with quantitative analysis of Doppler spectra enables reliable identification of renal allograft artery stenosis.

Ling Zhi-8: studies of a new immunomodulating agent

Ling Zhi-8 (LZ-8) is a protein derived from the fungus Ganoderma lucidum and has immunomodulatory capacities. It was shown to be mitogenic toward mouse splenocytes in vitro and immunosuppressive in vivo by reducing antigen-induced antibody formation and by preventing completely the incidence of autoimmune diabetes in nonobese diabetic mice. In this study, the mitogenic effects of LZ-8 on human mononuclear cells are reported. In accordance to its mitogenic effect on mouse splenocytes, LZ-8 proved to be mitogenic for human PBMC. This mitogenic effect of LZ-8 apparently required the presence of monocytes. We also demonstrated it to be immunosuppressive in vitro in a human MLC performed in the absence of monocytes, using purified T cells and EBV-transformed allogeneic B cells. Furthermore, we tested LZ-8 for its possible suppressive effects in 2 different models of allogeneic tissue transplantation. LZ-8 proved to have a significant effect on cellular immunity, since its administration in an allografted mouse skin model resulted in an increased survival time. In a model of transplanted allogeneic pancreatic rat islets, LZ-8 was effective in delaying the rejection process of allografted islets. More frequent or continuous administration resulted in a further prolongation of survival time. No serious side effects of LZ-8 could be discerned in these experiments.

The effects of cyclosporine and prednisone on serum lipid and (apo)lipoprotein levels in renal transplant recipients

Disturbances of lipid metabolism are frequently encountered after renal transplantation and have been ascribed to the use of cyclosporine (CsA) and corticosteroids, but the individual contribution of each of these drugs remains uncertain. The individual effects of CsA and prednisone (Pred) on serum lipid and (apo)lipoprotein levels were compared in a prospective randomized trial. All patients received CsA and Pred during the first 3 months after transplantation. Subsequently, they were allocated to either withdrawal of Pred or conversion from CsA to azathioprine (Aza). Serum lipids and (apo)lipoproteins, including lipoprotein(a) (Lp(a)), were measured at regular intervals during the first year after renal transplantation. Analysis of variance for repeated measures of the first year results showed higher values for serum triglycerides (P < 0.001) and lower high-density lipoprotein (HDL) cholesterol levels (P < 0.05) in the CsA monotherapy group (N = 59) as compared with the AzaPred group (N = 63). At 1 yr after transplantation, CsA-treated patients had significantly higher Lp(a) levels (CsA: median, 105 (interquartile range 42 to 340) mg/L; Aza-Pred: 46 (25 to 176) mg/L; P < 0.05). The withdrawal of Pred in the CsA group resulted in a large fall in HDL cholesterol (27 +/- 30% at 5 months after transplantation) and an increase in triglycerides (49 +/- 73% at 6 months). A reversion of these changes was observed in patients who were retreated with Pred. Multiple linear regression analysis showed an independent correlation between the use of Pred and HDL cholesterol level, whereas the use of CsA was independently associated with the concentration of Lp(a).(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of immunosuppressive drugs on quality of life after renal transplantation

This prospective, randomized study investigates the effect of two immunosuppressive treatment regimens on quality of life after renal transplantation. At 3 months after transplantation, patients treated with cyclosporine (CsA) and prednisone (Pred) were allocated to either withdrawal of Pred (n = 60) or to conversion of CsA to azathioprine (Aza) (Aza-Pred, n = 60). Quality of life was evaluated just before randomization, and at 6 and 12 months after transplantation using the Sickness Impact Profile (SIP), the Affect Balance Scale (ABS), the Center for Epidemiological Studies Depression Scale (CES-D), measures of satisfaction with several domains of life experience, and a population-specific physical symptoms questionnaire. In both groups, the overall SIP score as well as the scores on its physical and psychosocial dimensions improved continuously after transplantation, reaching levels that are comparable to those found in the general population. The occurrence of acute or chronic rejection had a significantly negative effect on SIP and CES-D scores. Intention-to-treat analysis showed no differences between groups for scores on SIP, ABS, CES-D, and satisfaction measures. Exclusion of 41 patients who did not strictly adhere to their originally designated therapy showed a tendency for better psychosocial SIP scores in CsA patients (P = 0.05), which mainly resulted from a difference on the category of social interaction (P = 0.01). This difference occurred despite a similar rejection rate and worse renal function in CsA-treated patients. Shortly after steroid withdrawal, a high proportion of CsA patients complained of stiff or painful muscles (CsA: 74%, Aza-Pred: 36%; P = 0.002). Our data indicate that if successfully completed, CsA monotherapy from 3 months after transplantation may lead to a higher degree of psychosocial well-being as compared with conversion from CsA-Pred to Aza-Pred. It seems likely that this advantage is related to the withdrawal of Pred.

Renal transplant thrombosis in children

Data concerning 100 consecutive renal transplantations in children were analyzed to determine factors enhancing the risk of renal transplant thrombosis. The incidence of renal transplant thrombosis was high, at 12%. It is concluded that in addition to young age and low body weight of recipient and young age of the donor, also a high preoperative urine production contributes to the occurrence of thrombosis. Children with hypoplastic or dysplastic kidneys are at greater risk for thrombosis. Considering the influence of high urine production of the native kidneys, it may be possible to prevent thrombosis by albumin and ample fluid administration.

Acute effects of nifedipine in renal transplant recipients treated with cyclosporine or azathioprine

Cyclosporine (CsA) impairs renal function, probably by preglomerular vasoconstriction. Vasodilating substances may therefore be of benefit to ameliorate CsA-induced renal dysfunction. We studied the acute effects on blood pressure and renal function of the dihydropyridine calcium antagonist nifedipine (10 mg orally) in 20 CsA-treated renal transplant patients. In addition, we compared the effects of nifedipine when given immediately before and 4 weeks after elective conversion from CsA to azathioprine. Compared with placebo (n = 14), administration of nifedipine led to a significant decrease in blood pressure and a strong natriuretic and diuretic response. Despite the reduction in blood pressure, glomerular filtration rate improved from 60 +/- 20 (mean +/- SD) to 69 +/- 24 mL/min/1.73 m2 (P < 0.001) and renal plasma flow (RPF) increased from 260 +/- 87 to 338 +/- 120 mL/min/1.73 m2 (P < 0.001). The combination of a decreased blood pressure with an increased RPF was reflected in a sharp decrease in renal vascular resistance (0.34 +/- 0.18 units v 0.23 +/- 0.10 units; P < 0.001). The conversion from CsA to azathioprine by itself led to significant increases in glomerular filtration rate (62 +/- 15 mL/min/1.73 m2 v 76 +/- 18 mL/min/1.73 m2; P < 0.05) and RPF (280 +/- 86 mL/min/1.73 m2 v 334 +/- 66 mL/min/1.73 m2; P < 0.05). During treatment with azathioprine an effect of nifedipine on glomerular filtration rate and RPF was no longer observed, although the natriuretic effect was similar on both occasions. The decrease in renal vascular resistance was larger during treatment with CsA than during treatment with azathioprine (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

The extent of peritubular CD14 staining in renal allografts as an independent immunohistological marker for acute rejection

Previously, we demonstrated that in acute interstitial rejection, immunohistological staining of renal allograft biopsies with the CD14 mAb WT14, reacting with human monocytes/macrophages, shows a characteristic peritubular increase of positive cells. To test the diagnostic value of this CD14 positivity, we compared, in 154 unselected renal allograft biopsies, the extent of peritubular WT14 staining with (a) the original histological diagnosis, made with knowledge of clinical data, (b) the retrospectively and blindly scored histological diagnosis according to the criteria of the Banff classification, and (c) the eventual clinical diagnosis, which included evaluation of the response to therapy. The extent of peritubular WT14 positivity, blindly scored on cryostat sections of the frozen part of the biopsies, correlated positively with the probability of acute rejection (AR). When using a cutoff of 70% WT14 positivity for the diagnosis of AR, as extracted from a receiver operating characteristic curve, the WT14 diagnosis had a positive predictive value of 91% and a negative predictive value of 56%, compared with the original histological diagnosis. Compared with the Banff diagnosis of AR (grade I-III), these values were 95% and 47%, and compared with the clinical diagnosis, 84% and 63%, respectively. The WT14 diagnosis essentially corrected the original histological diagnosis in 7 cases, and was consistent with the eventual diagnosis in 5 equivocal cases. We conclude that the extent of peritubular CD14 positivity can be used as a marker for AR and can serve as a valuable additional criterion for AR in the histological examination of renal allograft biopsies.

Doppler spectrum analysis to diagnose rejection during posttransplant acute renal failure

During posttransplant acute renal failure (ARF), the diagnosis of allograft rejection constitutes a major problem. We evaluated the value of Doppler ultrasonography in identifying grafts at risk of rejection during ARF. In 184 recipients of a renal allograft, Doppler examinations were performed on the first and fifth postoperative day. Doppler spectra were quantitatively analyzed with a user-written computer program. Doppler findings were not used in clinical decision making. ARF was defined as a diuresis < 400 ml/24 hr and/or the necessity for dialysis. Doppler spectra obtained on the first day after transplantation showed a resistance index (RI) of 0.59 +/- 0.09 in recipients with immediately functioning cadaveric grafts (n = 123), while living related donor grafts (n = 20) showed a lower RI (0.55 +/- 0.07; P < 0.05). Grafts with ARF (n = 41) showed a considerably higher RI (0.67 +/- 0.13; P < 0.05). When grafts with a duration of ARF < or = 4 days (n = 17) were compared with ARF > 4 days (n = 24), RI was not significantly different (0.63 +/- 0.07 vs. 0.68 +/- 0.15; NS). However, the acceleration time of the systolic deflection of the spectrum waveform (Tmax) was shorter in grafts with ARF > 4 days (86 +/- 47 msec vs. 128 +/- 39 msec; P < 0.05). On the fifth day after transplantation, Doppler spectra in grafts with ARF > 4 days (n = 24) showed a Tmax < 90 msec in 9 patients, 8 of whom experienced rejection during ARF (positive predictive value, 8/9 = 89%). In the 15 patients with Tmax > or = 90 msec, only 2 rejections occurred (negative predictive value, 13/15 = 87%). For the RI (> 0.85), positive predictive value was 4/5 = 80% and negative predictive value (RI < or = 0.85) was 13/19 = 68%. In conclusion, a short acceleration time of the Doppler waveform on the first day after transplantation is associated with a longer duration of ARF. Quantitative analysis of Doppler spectra can be helpful in the identification of patients at risk for rejection and in the timing of allograft biopsy during ARF. Persistently short Tmax values on the fifth day after transplantation perform better in identifying grafts at risk of rejection than high RI values.

Early detection of post-transplant pancreatic graft dysfunction with technetium-99m-HMPAO scintigraphy

We present two cases of compromised pancreatic graft perfusion on a routine 99mTc-HMPAO-scan. The radiopharmaceutical, hexamethylpropyleneamine oxime (HMPAO), labeled with 99mTc-provided high-quality scintigraphic images of transplanted pancreatic grafts. Findings were compared with subsequently performed x-ray digital subtraction angiographs. Pathological examination of both resected grafts revealed venous thrombosis in one case and graft pancreatitis in the other case of disturbed graft perfusion on a 99mTc-HMPAO-scan. While 99mTc-HMPAO scans of pancreatic grafts are not specific for early thrombosis, they seem to be a helpful tool in diagnosing pancreatic dysfunction in general, necessitating further diagnostic steps to elucidate the specific cause.

[Dysmorphic erythrocytes in urinary sediment in differentiating urological from nephrological causes of hematuria]

OBJECTIVE

To determine the significance of dysmorphic erythrocytes in the urinary sediment for discrimination between urological and nephrological causes of haematuria.

DESIGN

Evaluation of diagnostic test.

SETTING

Departments of Nephrology and Pathology, University Hospital Nijmegen.

METHOD

Of 107 patients with haematuria in whom renal parenchymal or urological disease was diagnosed, the percentage of dysmorphic erythrocytes was estimated in the unstained urinary sediment with normal light microscopy. By using a Receiver Operating Characteristic curve the cutoff point that provided the highest diagnostic value of the erythrocyte morphology was determined. In addition, the inter-observer variation was estimated in a separate series of 26 urinary sediments.

RESULTS

At a cutoff value of 40% dysmorphic erythrocytes the sensitivity for urological pathology was 100% and the specificity 66.7%. When presence of erythrocyte, haemoglobin or fatty casts was also considered as a criterion for a nephrological diagnosis, the specificity for urological pathology rose to 88.1%. The inter-observer variation showed a correlation coefficient of 0.90 (kappa: 0.77).

CONCLUSION

Evaluation of the erythrocyte morphology in the urinary sediment is a reliable aid in determining the strategy to be followed in patients with haematuria. It is important, however, that strict criteria for establishing erythrocyte dysmorphism are applied.

Computer simulations in comparison with in vivo measurements of nifedipine-induced changes in renal allograft hemodynamics

Analysis of Doppler spectrum waveforms is increasingly used in the differential diagnosis of human renal allograft dysfunction. The physiologic interpretation of changes in Doppler spectra obtained from renal allografts, however, remains a major problem. Computer simulation models of the renal circulation may provide insight into the physiologic mechanisms responsible for changes in Doppler spectrum characteristics. The results of measurements of renal allograft hemodynamics with both determinations of PAH clearance and Doppler spectrum analysis in 11 kidney allograft recipients were explained physiologically using a computer simulation model of kidney allograft hemodynamics. Using PAH clearance and blood pressure measurements a significant decrease in RVR was found (from 0.32 +/- 0.17 to 0.20 +/- 0.07 mm Hg x min/ml, P < 0.05) after administration of the vasodilatory drug nifedipine. The Doppler spectrum waveform obtained from interlobar renal arteries showed a decrease in the RI (from 0.60 +/- 0.04 to 0.56 +/- 0.06; P < 0.05) and Tmax (from 133 +/- 32 to 98 +/- 32 ms; P < 0.05). The user-designed simulation model of renal hemodynamics showed comparable changes of the waveform when, in the model, the analogs of blood pressure, impedance of the artery, and the impedance of the peripheral vascular bed were altered proportionally.

Iliac artery stenosis after kidney transplantation

In human kidney transplantation hypertension and renal dysfunction are common complications. Diagnosis of vascular involvement may frequently be necessary. Although iliac artery stenosis is a rare complication after renal transplantation, it can be the cause of hypertension and renal dysfunction. Because colour duplex scanning is a repeatable non-invasive technique, it may provide a useful tool in establishing a diagnosis of iliac artery stenosis in patients with hypertension and/or renal dysfunction. We present four cases of iliac artery stenosis in kidney allograft recipients. Colour duplex scanning was used in these patients to detect and localize the stenosis. Quantitative analysis of Doppler spectra was used to compare the Doppler spectrum waveforms obtained from both femoral arteries and from the kidney allograft arteries of these patients with the normal range. This normal range was determined from Doppler spectra obtained in a control group of 21 kidney allograft recipients. Clinical data, arterial DSA, and the outcome of treatment were used to validate colour duplex findings in the patients with iliac artery stenosis. Quantitative analysis of Doppler spectra showed differences between the femoral artery on the affected side and the contralateral side outside the normal range. In three patients the iliac artery stenosis was located proximal from the anastomosis with the kidney allograft artery and in these three patients Doppler parameters obtained from the allograft artery were also outside the normal range. In one patient the stenosis was located distally from the anastomosis with the kidney allograft artery. In this case Doppler spectra from the kidney allograft artery were within the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)

High incidence of arteriovenous fistula after biopsy of kidney allografts

Arteriovenous fistula (AVF) is a well known but rarely diagnosed complication of percutaneous biopsy of kidney allografts. In the past diagnosis was usually made when clinical signs of an AVF occurred but Doppler ultrasonography has now enabled non-invasive diagnosis. Doppler examination of kidney allografts was performed after 100 biopsies. A total of ten AVFs were diagnosed within 2 weeks of biopsy. On repeated examination 2 months later, no additional fistula was detected. All fistulas were detected by abnormal colour shading of the artery and vein of the fistula caused by high blood velocity. Quantification in the artery supplying the fistula showed a higher systolic velocity compared with that in a normal artery of comparable size and location in the graft (mean (range) 64 (25-150) versus 36 (20-65) cm/s, P < 0.05). Diastolic velocity was also higher in the artery supplying the fistula than in a normal artery (mean (range) 34 (9-72) versus 7 (0-13) cm/s, P < 0.05). In the group with an AVF the proportion with a prolonged bleeding time (> 3 min) was higher (80 versus 47 per cent, P < 0.05), as was the prevalence of a platelet count < 200 x 10(9)/l (60 versus 22 per cent, P < 0.05). After detection of the fistula, four of the grafts were lost because of rejection and two patients died from sepsis during antirejection treatment. During follow-up of the remaining four AVFs, three disappeared spontaneously and one persisted. None of the fistulas has had an impact on renal function requiring intervention. In conclusion, AVF is a complication observed frequently after kidney allograft biopsy that can be detected and monitored by Doppler ultrasonography.

Renal allograft artery stenosis: results of medical treatment and intervention. A retrospective analysis

In a retrospective analysis of 1165 renal transplantations in our center, 65 cases of renal allograft artery stenosis were diagnosed angiographically (prevalence 5.5%). Hypertension was present in all cases; a bruit over the allograft and an increase in serum creatinine level were additional reasons for angiography. Shortly after diagnosis of the stenosis, two patients died and two others lost their grafts due to thrombosis. In 24 patients the decision was made not to correct the stenosis. One of these grafts was lost because the stenosis could not be corrected. Medical management of hypertension in these patients resulted in a decrease in diastolic blood pressure from 109 +/- 22 to 96 +/- 12 mm Hg (P < 0.01) 3 months after diagnosis with the use of almost twice as many antihypertensive drugs as at the time of diagnosis (P < 0.01). The stenosis was corrected if the angiography showed it to be so severe that it jeopardized renal allograft function or caused uncontrollable hypertension. Only three of nine percutaneous transluminal angioplasty (PTA) procedures resulted in a definitive correction of the stenosis. Surgical intervention was performed in 30 patients, including two patients whose PTAs had proved unsuccessful. Surgery led to graft loss due to thrombosis in 6 of 30 operations (20%), whereas restenosis occurred twice (7%). In three other cases (10%), the correction was not successful due to local anatomical variations or concomitant rejection.(ABSTRACT TRUNCATED AT 250 WORDS)