Apolipoprotein A-Ib as a biomarker of focal segmental glomerulosclerosis recurrence after kidney transplantation: diagnostic performance and assessment of its prognostic value - a multi-centre cohort study

Recurrence of idiopathic focal segmental glomerulosclerosis (FSGS) is a serious complication after kidney transplantation. FSGS relapse is suspected by a sudden increase in proteinuria but there is not an accurate noninvasive diagnostic tool to confirm this entity or to detect patients at risk. We aimed to validate the diagnostic performance of ApoA-Ib to detect FSGS relapses by measuring urinary ApoA-Ib in a retrospective cohort of 61 kidney transplanted patients (37 FSGS and 24 non-FSGS). In addition, to assess the ApoA-Ib predictive ability, ApoA-Ib was measured periodically in a prospective cohort of 13 idiopathic FSGS patients who were followed during 1 year after transplantation. ApoA-Ib had a sensitivity of 93.3% and a specificity of 90.9% to diagnose FSGS relapses, with a high negative predictive value (95.2%), confirming our previous results. In the prospective cohort, ApoA-Ib predated the recurrence in four of five episodes observed. In the nonrelapsing group (n = 9), ApoA-Ib was negative in 37 of 38 samples. ApoA-Ib has the potential to be a good diagnostic biomarker of FSGS relapses, providing a confident criterion to exclude false positives even in the presence of high proteinuria. It has also the potential to detect patients at risk of relapse, even before transplantation.

Cysteamine (Cystagon®) adherence in patients with cystinosis in Spain: successful in children and a challenge in adolescents and adults

Background

Cysteamine has improved survival and prognosis in cystinosis. Increasing numbers of patients reach adulthood and face new challenges such as compliance that wanes over time. The aim of this study was to evaluate adherence to cysteamine treatment in a group of cystinotic patients in Spain in an attempt to identify potential therapy pitfalls and improve the overall care of affected individuals. Despite the impact of cysteamine on prognosis, there is a paucity of data regarding adherence.

Method

Thirty-four cystinotic patients (21 male) 38% ≥18 years were enrolled in a voluntary, anonymous survey. Replies were obtained from patients (15/34), mothers (11/34), fathers (4/34) and both parents (4/34).

Results

Patient age (median and interquartile range) at diagnosis was 1 year (0.57–1), and patient age at Cystagon® initiation was also 1 year (0.8–1.8). Sixteen (47%) were kidney transplant (KTx) recipients; six were retransplanted. Age at first KTx 10 years (8.7–13.7). Patient understanding of multiorgan involvement in cystinosis: 4.1 organs reported; eye 97% and kidney 91%. Cysteamine was given by mother (100%) and father (83%) in <11 year olds, or self-administered (94%) in ≥11 year olds. Four daily doses in 89% versus 56% in <11 year olds or ≥11 year olds, with fixed schedule in 94% versus 50% in <11 or ≥11 year olds and progressive loss of reminders over time. Furthermore, 44% complained of unpleasant smell. Motivation for treatment compliance was 100% versus 40% in <11 versus ≥11 year olds, respectively. Disease impact in patients <18 years is as follows: school (29%), social (14%), ‘feeling different’ (10%); in patients ≥18 years: ‘feeling different’ (62%), professional (39%) and job absenteeism (31%). Referring physician: paediatric nephrologist (94%) and nephrologist (63%) in <11 versus ≥11 year olds. Ophthalmological follow-up: 83% versus 38% in <11 versus ≥11 year olds. Patient opinion of physician expertise: paediatric nephrologist (94%) and nephrologist (44%). New treatment options (65%) and better information (42%) were demanded to improve adherence.

Conclusion

Treatment with Cystagon is effective in young patients. However, adherence diminishes over time in adolescents and adults despite disease impact. Strategies such as better information on the disease, patient self-care promotion and facilitated transition to adult healthcare services are required to improve compliance and the clinical management of cystinosis.

Native ureteropyelostomy in the treatment of obstructive uropathy in adult renal transplant. Experience and technical alternatives

OBJECTIVE

To analyze and evaluate our experience in surgical treatment with the open approach of the complex ureteral stenosis after adult kidney transplantation in a tertiary level hospital in the last seven years. We have reviewed the different surgical options used.

PATIENTS AND METHODS

A total of 589 consecutive adult renal transplants were performed from January 2005 to December 2012. Of these, 1.1% showed some degree of symptomatic obstructive uropathy which after initial urinary diversion required open surgical approach using the ipsilateral or contralateral native urinary tract. Characteristics of the patient, clinical examinations performed and surgical technique performed as well as their results are presented.

RESULTS

During the period under review, in 5 men and 2 women who had ureteral stenoses after renal transplant, 7 reparative surgeries were performed by open ureteropyelostomy, using ipsilateral native ureter in 6 cases and contralateral ureter in the remaining case. In one case, uretero-calicial anastomosis was performed due to severe pyelic shrinkage. There were no significant complications. Native kidney nephrectomy was not required for further complications. All the patients operated on had optimum plasma creatinine levels with resolution of previous dilatation.

CONCLUSIONS

The initial percutaneous nephrostomy followed by open surgical repair using native ureter represents a definitive, valid and optimal alternative in terms of safety and preservation of renal function.

Cirrhosis, liver transplantation and HIV infection are risk factors associated with hepatitis E virus infection

BACKGROUND

Acute and chronic hepatitis E have been associated with high mortality and development of cirrhosis, particularly in solid-organ recipients and patients infected by human immunodeficiency virus. However, data regarding the epidemiology of hepatitis E in special populations is still limited.

AIMS

Investigate seroprevalence and possible factors associated with HEV infection in a large cohort of immunosuppressed patients.

METHODS

Cross-sectional study testing IgG anti-HEV in serum samples from 1373 consecutive individuals: 332 liver-transplant, 296 kidney-transplant, 6 dual organ recipients, 301 non-transplanted patients with chronic liver disease, 238 HIV-infected patients and 200 healthy controls.

RESULTS

IgG anti-HEV was detected in 3.5% controls, 3.7% kidney recipients, 7.4% liver transplant without cirrhosis and 32.1% patients who developed post-transplant cirrhosis (p<0.01). In patients with chronic liver disease, IgG anti-HEV was also statistically higher in those with liver cirrhosis (2% vs 17.5%, p<0.01). HIV-infected patients showed an IgG anti-HEV rate of 9.2%, higher than those patients without HIV infection (p<0.03). Multivariate analysis showed that the factors independently associated with anti-HEV detection were liver cirrhosis, liver transplantation and HIV infection (OR: 7.6, 3.1 and 2.4). HCV infection was a protective factor for HEV infection (OR: 0.4).

CONCLUSIONS

HEV seroprevalence was high in liver transplant recipients, particularly those with liver cirrhosis. The difference in anti-HEV prevalence between Liver and Kidney transplanted cases suggests an association with advanced liver disease. Further research is needed to ascertain whether cirrhosis is a predisposing factor for HEV infection or whether HEV infection may play a role in the pathogeneses of cirrhosis.

A form of apolipoprotein a-I is found specifically in relapses of focal segmental glomerulosclerosis following transplantation

Recurrence of idiopathic focal segmental glomerulosclerosis (FSGS) following kidney transplantation occurs in a large percentage of patients. Accurate prediction of recurrence and elucidation of its pathogenesis are major therapeutic goals. To detect differential proteins related to FSGS recurrence, proteomic analysis was performed on plasma and urine samples from 35 transplanted idiopathic FSGS patients, divided into relapsing and nonrelapsing. Several proteins were detected increased in urine of relapsing FSGS patients, including a high molecular weight form of apolipoprotein A-I, named ApoA-Ib, found exclusively in relapsing patients. This finding was verified by Western blot individually in the 35 patients and validated in an independent group of 40 patients with relapsing or nonrelapsing FSGS, plus two additional groups: FSGS-unrelated patients showing different proteinuria levels (n = 30), and familial FSGS transplanted patients (n = 14). In the total of 119 patients studied, the ApoA-Ib form was detected in 13 of the 14 relapsing FSGS patients, and in one of the 61 nonrelapsing patients. Only one of the 30 patients with FSGS-unrelated proteinuria tested positive for ApoA-Ib, and was not detected in familial patients. Urinary ApoA-Ib is associated with relapses in idiopathic FSGS and warrants additional investigation to determine its usefulness as biomarker of relapse following transplantation.

The natural history of clinical operational tolerance after kidney transplantation through twenty-seven cases

We report here on a European cohort of 27 kidney transplant recipients displaying operational tolerance, compared to two cohorts of matched kidney transplant recipients under immunosuppression and patients who stopped immunosuppressive drugs and presented with rejection. We report that a lower proportion of operationally tolerant patients received induction therapy (52% without induction therapy vs. 78.3%[p = 0.0455] and 96.7%[p = 0.0001], respectively), a difference likely due to the higher proportion (18.5%) of HLA matched recipients in the tolerant cohort. These patients were also significantly older at the time of transplantation (p = 0.0211) and immunosuppression withdrawal (p = 0.0002) than recipients who rejected their graft after weaning. Finally, these patients were at lower risk of infectious disease. Among the 27 patients defined as operationally tolerant at the time of inclusion, 19 still display stable graft function (mean 9 ± 4 years after transplantation) whereas 30% presented slow deterioration of graft function. Six of these patients tested positive for pre-graft anti-HLA antibodies. Biopsy histology studies revealed an active immunologically driven mechanism for half of them, associated with DSA in the absence of C4d. This study suggests that operational tolerance can persist as a robust phenomenon, although eventual graft loss does occur in some patients, particularly in the setting of donor-specific alloantibody.

Development and validation of a specific questionnaire for evaluating the impact of gastrointestinal symptoms on the health-related quality of life of transplant patients

BACKGROUND

Transplant patients receiving immunosuppressant treatment suffer gastrointestinal symptoms (GIS) limiting their health-related quality of life (HRQOL) and causing dose redíuctions and discontinuations.

METHODS

This observational, multicenter, cross-sectional study aims to develop and validate a questionnaire for detecting and quantifying the impact of GIS on the HRQOL of patients with functioning organ transplants. We developed a pilot version of the questionnaire SIGIT-QOL (Impact of Gastrointestinal Symptoms on Quality Of Life) and then evaluated the feasibility, validity, and reliability. We consecutively recruited 274 solid organ transplant patients from 20 hospitals. Sociodemographic and clinical data were collected. Patients completed the SIGIT-QOL and Gastrointestinal Quality of Life Index-GIQLI- questionnaires.

RESULTS

Mean age was 52.7 (SD, 7.59) and 181 were male; 43.4% showed an episode of GIS since transplantation (3-12 months before). Of all patients, 95.3% completed the SIGIT-QOL. Mean time of completion was 6.49 minutes. Exploratory factorial analysis identified a 1-dimensional structure (42% of total variance). Internal consistency was high (Cronbach's alpha, 0.889). A significant association was found between the SGITI-QOL and the presence of GIS (P < .01). Finally, correlation coefficients between SIGIT-QOL and GIQLI were moderate-high except for Social Function.

CONCLUSION

The brief SIGIT-QOL questionnaire can detect and quantify the GIS and their impact on the HRQOL of solid organ transplant patients.

Efficacy and safety of conversion from twice-daily to once-daily tacrolimus in a large cohort of stable kidney transplant recipients

Prolonged-release tacrolimus was developed to provide a more convenient once-daily dosing that could improve patient adherence. We conducted a multicenter, prospective, observational, 12-month study to describe the efficacy, safety and patient preference of conversion from tacrolimus twice-daily to once-daily formulation in stable kidney transplant recipients in routine clinical practice. Conversion was made on a 1 mg: 1 mg basis (1 mg: 1.1 mg in patients with trough levels <6 ng/mL). The study included 1832 patients (mean age (± SD): 50.0 ± 13.4 years; 62.7% male). After conversion, a modest reduction in tacrolimus trough levels, necessitating an increase in daily dose, was observed (mean changes at 12 months of -9.1% and +1.24%, respectively; p < 0.0001). Mean glomerular filtration rate did not change significantly (56.5 ± 19.7 mL/min at conversion vs. 55.7 ± 20.6 mL/min at 12 months). Proteinuria, blood pressure, lipid, hepatic and glucose parameters remained stable. Eight patients (0.4%) had acute rejection and 34 patients (1.85%) discontinued treatment. Almost all patients (99.4%) preferred the once-daily formulation, because of less frequent dosing (66%) and improved adherence (34%). In conclusion, at similar doses to twice-daily tacrolimus, once-daily formulation provided stable renal function, a low acute rejection rate, and good tolerability in stable kidney transplant recipients in the routine clinical practice setting.

Histological findings in two renal transplants accomplishing operational tolerance criteria

Operational tolerance is defined as stable renal function in transplants without immunosuppression for at least 1 year. We present histological assessments of two patients with operational tolerance. The first withdrew immunosuppression in 2005 and presents stable renal function (creatinine 1.5 mg/dL) without proteinuria. The biopsy showed mild chronic tubulointerstitial changes without inflammation. The second withdrew immunosuppression in 2009 and maintains stable renal function (creatinine 1.6 mg/dL) with mild proteinuria. Histology showed chronic humoural rejection and Class II anti-human leukocyte antigen antibodies were detected. These cases suggest that a renal biopsy may be useful to rule out subclinical pathology in patients with operational tolerance.

Heterogeneity of induction therapy in Spain: changing patterns according to year, centre, indications and results

Background. The use of induction drugs has increased markedly over the last 15 years in the USA, but there are few data about their use in other countries. Moreover, there are not enough data about when they are indicated and their long-term effects. The aim of our study was to know the rates of use and the drugs used as induction therapy, in which patients they were prescribed and the long-term graft survival effect in Spain.

Methods. We conducted a retrospective cohort study with adult patients (4861) receiving a kidney allograft in Spain over four different years (1990, 1994, 1998 and 2002) with a functioning graft at the end of the first post-transplant year. Induction therapy was defined as when the patient received polyclonal antibodies, OKT3 monoclonal antibodies or anti-CD25 monoclonal antibodies.

Results. From 1990 to 2002, the use of induction therapy in Spain changed, with a progressive reduction in the use of OKT3 and an increasing use of anti-CD25 antibodies. There were great differences in the rate of induction use from one centre to another, although with a common trend to greater use at each centre. Induction therapy was mainly prescribed in patients with a higher rejection risk (higher panel reactive antibody (PRA) titres and mismatches and re-transplants) and in older and diabetic recipients. Lastly, patients who were treated with induction therapy had significant higher allograft survival than those who did not (P value = 0.035).

Conclusions. The use of induction therapy in Spain has changed, with an increasing use of monoclonal antibodies in recent years. Induction therapy has a protective role in long-term graft survival.

[Daclizumab in combination with mycophenolate mofetil and a late introduction of Tacrolimus at low doses, as a therapeutic approach in the elderly renal transplant donor-recipients pairs in kidney transplant]

BACKGROUND

Nowadays, it is more frequent the use of kidneys from older donors in the renal transplantation. Moreover, it is also increasing the age of the recipients due to the ageing of the population treated with hemodialysis. This makes that recipients become older more commonly. This situation raises specific problems in the renal graft and in the recipient as well. In this manuscript we present the results of a multicenter study that analyzed an immunosuppressive strategy specifically designed to elderly renal transplant donor-recipients.

METHODS

Patients > or =50 years were transplanted from donors > or =55 years. Immunosuppressive strategy consisted of daclizumab (2 doses of 1mg/Kg) in combination with steroids, mycophenolate mofetil (2g/daily during the first 45 days and then adjusted according to local practice) and Tacrolimus. Tacrolimus was introduced between 5 and 7 day post-transplantation, adjusting the predose levels between 4-8 ng/mL. Mean follow-up was 12 months.

RESULTS

A total of 133 patients were included in the study. Mean age of recipients and donors was 61.3+/-6.2 years and 64.4+/-5.3, respectively. 42.9% of patients needed dialysis during the first week (median 4 days). Between first month and first year, serum creatinine improved from 2.0+/-1.0 mg/dl to 1.5+/-0.4 mg/dl. Similar improvements were observed when creatinine clearance (Cockroft-Gault) was calculated. The survival of patient and renal graft at 12 months was 97.7% and 96.1%, respectively. The acute rejection rate was 13.5%. Security profile was good, as expected.

CONCLUSIONS

The Daclizumab and mycophenolate mofetil regimen with a late introduction of Tacrolimus at low doses is a good alternative in the elderly renal transplant recipients with a low immunologic risk.

Use of the New Proliferation Signal Inhibitor Everolimus in Renal Transplant Patients in Spain: Preliminary Results of the EVERODATA Registry

Everolimus (Eve) has shown good efficacy and safety profiles in clinical trials in combination with low doses of cyclosporine but there is limited experience in other modes, especially with calcineurin inhibitor elimination. We developed a retrospective study to analyze its clinical use after approval in Europe in 2005. Herein we have presented the results of a series of 272 patients followed for the first 6 months after Eve introduction. In 93.8% of cases Eve was introduced after the first month posttransplantation (conversion use), and 6 months after introduction, the CNI had been eliminated in 75% of cases. The main indication for Eve introduction was the diagnosis of a malignant neoplasm (42%), whereas the combined indication of prevention and/or treatment of toxicity, especially nephrotoxicity, accounted for 46.3% of cases. Initial doses were low (1.37 mg/d), but were progressively increased up to 2 mg/d at 6 months. Renal function remained unchanged during the follow-up period, whereas proteinuria moderately increased. Only 5 cases (2%) of acute rejection episodes were observed with excellent patient and graft survivals at 6 months after conversion. Further analysis of this extensive series of patients with a longer follow-up is needed.

Two doses of daclizumab with delayed introduction of low-dose tacrolimus in elderly recipients of cadaveric renal transplants from donors >55 years of age

BACKGROUND

Renal transplants from elderly donors have a high incidence of delayed graft function, which can be increased by the initial use of calcineurin inhibitors. Our purpose was to assess the safety and efficacy of an immunosuppressive regimen using anti-IL-2R antibodies and MMF that allows delayed introduction of low-dose tacrolimus using elderly donors to elderly recipients.

METHODS

This observational study involved 13 transplant centers. In total there were 119 patients (age 60.5 +/- 6.6 years, range 50 to 77) who received a kidney from a donor of mean age 64 +/- 5 years (range 55 to 76), 94% of whom died from a CVA. Immunosuppression consisted of daclizumab (1 mg/kg in two doses; preoperatively and on day 14) combined with steroids, mycophenolate mofetil (initial dose of 2 g/d), and tacrolimus (0.1 mg/kg per day). Tacrolimus was introduced before day 7 (mean 5.5 days) and adjusted to a target level of 5 to 8 ng/mL. The mean follow-up was 8 months.

RESULTS

Two grafts were lost due to primary nonfunction and acute rejection and 48 patients (40%) required dialysis due to delayed graft function, although it was generally of short duration (median 4 days; only 2 cases >2 weeks). Acute rejection occurred in 16 patients (13.4%), of whom 13 were biopsy-confirmed (10.9%; Banff 1997 grades I and II). Three patients withdrew from the study, and three died (sepsis, accident, and cardiovascular event). The remaining 111 patients continued follow-up, with a median creatinine value of 1.5 mg/dL at 12-months. Eighty-six percent of patients had at least one episode of infection, half of which were urinary tract infections. There were 16 cases of CMV infection.

CONCLUSIONS

Based on the initial results, our immunosuppressive regimen seems to offer good short-term renal function while maintaining an acceptable rejection rate and a low incidence of serious infections.

Cost of Renal Transplant Maintenance Immunosuppression: Effect of Control of Vascular Risk Factors

In 3 renal transplant cohorts treated in Spain in 1990, 1994, and 1998 (total number, 3279), we studied the frequency of certain cardiovascular risk factors. Their effect on the cost of drugs was assessed from the data from 1 center; the mean cost of antihypertensive agents per patient-year was 349 euros, and of lipid-lowering drugs was 294 euros. Between 1990 and 1998 the frequency of use of antihypertensive agents at 2 years increased from 70% to 80%, and that of lipid-lowering agents from 12% to 46% (P < .001). Patients received various regimens of immunosuppression at the second year, as follows: (1) steroid-free: cyclosporine, 2.3%; tacrolimus, 9.9%; cyclosporine plus mycophenolate, 16.2%; and tacrolimus plus mycophenolate, 11.8% (P < .001); (2) antihypertensive agents: 74.9% of patients receiving tacrolimus, with or without mycophenolate, versus 80.7% of those receiving cyclosporine (P = .022); (3) lipid-lowering drugs: 28.4% of patients receiving tacrolimus, with or without mycophenolate, versus 51.1% of those receiving cyclosporine (P < .001). The increase in associated drug costs must be added to the recent large increase in the cost for immunosuppressive agents, which rose from 3854 euros per year, in 1990 to 5374 euros per year in 1998. A lower cost of associated drugs tends to lessen the overall cost of therapies with tacrolimus. Because cardiovascular disease is the main cause of death, these findings should be taken into account in the assessment of the long-term cost-benefit ratio.

Effect of New Immunosuppressive Regimens on Cost of Renal Transplant Maintenance Immunosuppression

Although newer immunosuppressive drugs control acute rejection better and have short-term economic advantages, their long-term cost-effectiveness is unknown. We studied the frequency with which different maintenance immunosuppression regimens were used in 3 renal transplantation cohorts treated in 1990, 1994, and 1998 (total number, 3279). We calculated the mean annual immunosuppressive costs based on the true costs in a medium-sized hospital. Cyclosporine, with or without azathioprine, was used almost exclusively as the initial maintenance immunosuppressive therapy in 1990-1994. In 1998, 65% of patients received mycophenolate mofetil (MMF), and 20% received tacrolimus (Tac). A growing number of patients from 1990-1994 were converted to MMF (12%-17%) and Tac (4%-8%), while treatment of those from the 1998 cohort remained stable. According to year 2000 costs, the mean immunosuppressive cost at 1 year in 1998 (5380 euros) was almost twice that of 1994 (2902 euros) or 1990 (2855 euros). In these 2 groups the mean cost was stable until 1996, then increased faster in the 1994 cohort (24.8%) than in the 1990 cohort (17.3%), although it remained significantly lower than that in 1998. Correction of the evolution of drug prices and the purchasing value of the peseta greatly absorbed these changes. The MMF and Tac regimens showed greater mean graft life, but without reaching statistical significance in a multivariate study. The introduction of new immunosuppressive drugs has had an important economic effect since 1996; its cost-effectiveness is still pending confirmation in Spain.

Safety and efficacy of delayed introduction of low-dose tacrolimus in elderly recipients of cadaveric renal transplants from donors over 55 years of age

BACKGROUND

Renal transplants (RTs) from elderly donors show a high incidence of delayed graft function, which may be increased by the initial use of calcineurin inhibitors.

OBJECTIVES

The purpose of this study was to assess the safety and efficacy of an immunosuppressive regimen using anti-IL-2R antibodies and mycophenolate mofetil (MMF) with delayed introduction of low-dose tacrolimus in RT from elderly donors to elderly recipients.

METHODS

This observational study in 13 centers included 78 patients, aged 61+/-7 years (range, 50-77), who received a kidney from a donor with a mean age of 64+/-5 years (range, 55-76), 94% of whom had died from a cardiovascular accident (CVA). Immunosuppression consisted of 1 mg/kg daclizumab in two doses (pre-RT and on day 14) combined with steroids, mycophenolate mofetil (initial dose of 2 g/d), and tacrolimus (0.1 mg/kg per day). Tacrolimus was introduced before day 7 (mean, 5.5 days) and adjusted to a target level of 5 to 8 ng/ml. The mean follow up was 27 weeks.

RESULTS

One graft was lost due to primary renal failure and 28 patients (36.4%) required dialysis due to delayed graft function, although it was generally of short duration (median, 4 days; only 2 cases >2 weeks). Acute rejection was seen in 11 patients (14%), with 9 of these confirmed by biopsy (11%, Banff 1997 grade I or II). Three patients withdrew from the study and two patients died (sepsis and accident). The remaining 72 patients continued follow up with a median 6-month creatinine value of 1.6 mg/dL. Sixty-seven percent of patients had at least one episode of infection, half of which were of urinary tract infections. There were nine cases of CMV infection.

CONCLUSIONS

These initial results suggest that this immunosuppressive regimen offers good efficacy with regard to short-term renal function, while maintaining both an acceptable low rejection rate and incidence of serious infections.

Helical CT in renal transplantation: normal findings and early and late complications

Over a 5-year period, 346 helical computed tomographic (CT) studies were performed in renal transplant recipients. Helical CT proved useful in this context by depicting parenchymal, perirenal, renal sinus, pyeloureteral, and vascular complications in great detail. CT often delineates fluid collections and their anatomic relationship to adjacent structures better than ultrasonography (US), particularly in obese patients. CT-guided puncture and drainage can be performed in cases in which US is deemed inadequate. CT angiography can depict arterial diseases such as stenosis, thrombosis, arteriovenous fistulas, aneurysms, and pseudoaneurysms in the graft artery and in the recipient iliac arterial system, thereby obviating conventional angiography in some cases. Helical CT with three-dimensional image reformatting allows accurate imaging of the entire course of ureteral and periureteral diseases (eg, hydronephrosis, ureteral leak and stricture, pyeloureteral obstruction). CT can be used in the confirmation and staging of malignancies of the renal parenchyma and urothelium. It is also helpful in evaluating associated disease in the native kidneys, acute and chronic rejection, graft embolization, and end-stage disease. Although US and nuclear medicine examination are the imaging modalities of choice in renal transplantation, helical CT is a valuable alternative when these techniques are inconclusive.

Mycophenolic acid plasma concentrations: influence of comedication

Mycophenolate mofetil (MMF) in combination with cyclosporine (CsA) or Tacrolimus (TAC) has been show to be a potent immunosuppressive agent. The authors assessed the mycophenolic acid (MPA) plasma levels achieved in clinical practice and evaluated the effect of concomitant administration of CsA and TAC . One hundred forty transplant patients (kidney: 120 and lung: 20) received a triple immunosuppression regimen of CsA or TAC, prednisone and MMF. Twenty-two renal transplant patients received double therapy with MMF and prednisone. There was no correlation between MMF dose and MPA trough concentrations (r = -0.0657). The medians (range) of the MPA dose-to-concentration ratio (D/C) in the CsA and TAC groups were 0.90 (0.11-8.33) and 0.56 (0.11-14.3), respectively (p < 0.0001). According to the post transplant period (1-3, 4-6 and >6 months), D/C values were significantly lower in patients receiving MMF and TAC than those receiving MMF and CsA in all three periods. MPA levels in patients treated with MMF and CsA were significantly lower than those obtained in double therapy. The D/C ratio in CsA-treated patients, increased significantly (p = 0.0005) when CsA level increased. There was no relationship between D/C ratio and TAC blood concentrations. These results suggest that CsA exerts an influence on MPA trough levels, although further work is required to characterize the mechanism of interaction.

Mycophenolate mofetil pharmacokinetics in transplant patients receiving cyclosporine or tacrolimus in combination therapy

Mycophenolate mofetil is a highly effective immunosuppressant drug used in the prophylaxis of organ rejection in combination with cyclosporine or tacrolimus and corticosteroids. The present study is a retrospective data analysis of the routinely estimated mycophenolic acid plasma trough levels in 60 transplant patients (kidney, n = 49; lung, n = 11) receiving mycophenolate mofetil in combination with prednisone and cyclosporine (n = 45) or tacrolimus (n = 15). Coadministration of cyclosporine instead of tacrolimus resulted in a significant increase of median (range) of the ratio of dose-to-concentration 0.92 (0.11-8.33) (n=167) versus 0.38 (0.11-14.28) (n = 66); P < 0.0001. No correlation was seen between mycophenolate mofetil dose and mycophenolic acid trough concentrations. The dose-to-concentration in cyclosporine-treated patients increased significantly (P<0.0001) as the cyclosporine level increased, suggesting a possible interaction between mycophenolate mofetil and cyclosporine. No correlation was seen between dose-to-concentration and tacrolimus blood levels (P x 0.215). Further studies are necessary to investigate this issue.

Serum cholesterol changes in long-term survivors of liver transplantation: a comparison between cyclosporine and tacrolimus therapy

The aim of this study was to compare the long-term effect of tacrolimus and cyclosporine therapies on serum cholesterol levels in liver transplant recipients. We retrospectively studied 127 consecutive adult liver transplant recipients who survived for at least 1 year after transplantation. Basal immunosuppression consisted of cyclosporine plus prednisone in 100 patients and tacrolimus plus prednisone in 27 patients. Hypercholesterolemia was defined as a fasting serum cholesterol level greater than 220 mg/dL. Mean follow-up was 39 months. No statistical significance was found between cyclosporine- and tacrolimus-treated patients regarding age, sex, diagnosis, and previous cholesterol levels; both groups were similar. Significantly more tacrolimus-treated patients were steroid free in the first and second year of follow-up (tacrolimus, 37% and 63%; cyclosporine, 13% and 32%, respectively; P <.01). In the third year of follow-up, this difference was not significant (77% v 56%). The overall incidence of hypercholesterolemia was 34.6% (44 patients). At the end of the study, hypercholesterolemia was found in 24 of 51 and 14 of 70 patients with and without steroids, respectively (P <.002). Also, mean cholesterol levels were 224 +/- 70 and 191 +/- 48 mg/dL before and after steroid withdrawal, respectively, P <.001. Hypercholesterolemia was found in 43.7% of the patients during cyclosporine plus prednisone therapy compared with 46.1% of the patients during tacrolimus plus prednisone therapy (P <.9). Greater mean cholesterol levels were found in the cyclosporine group, particularly in the second and third years of follow-up (P <.01). Hypercholesterolemia was found in 22% of the patients during cyclosporine monotherapy compared with 15% during tacrolimus monotherapy (P <.5). No differences were found in mean cholesterol levels during follow-up when both monotherapy groups were compared. In conclusion, a lower incidence of hypercholesterolemia was achieved in tacrolimus-treated patients, mainly when steroids were still part of the immunosuppressive treatment.

Clinical presentation and outcome of tuberculosis in kidney, liver, and heart transplant recipients in Spain. Spanish Transplantation Infection Study Group, GESITRA

BACKGROUND

Tuberculosis is unusual in transplant recipients. The incidence, clinical manifestations, and optimal treatment of this disease in this population has not been adequately defined. The present study was undertaken to assess the incidence, clinical features, and response to therapy of Mycobacterium tuberculosis infection in solid-organ transplant recipients.

METHODS

We evaluated retrospectively the incidence, clinical characteristics, diagnostic procedures, antituberculous treatment, clinical course, and factors influencing mortality in 51 solid-organ transplant recipients who developed tuberculosis after transplantation. We also reviewed the world literature on tuberculosis in solid-organ transplantation.

RESULTS

The overall incidence of tuberculosis was 0.8%. The localization was pulmonary in 63% of the cases, disseminated in 25%, and extrapulmonary in 12%. Tuberculosis developed from 15 days to 13 years after surgery (mean, 23 months). In one third of the cases, diagnosis was not suspected initially, and in three cases, diagnosis was made at necropsy. Fever was the most frequent symptom, followed by constitutional symptoms, cough, respiratory insufficiency, and pleuritic pain. Fifteen patients (33%) developed hepatotoxicity during treatment; hepatotoxicity was severe in seven cases. Hepatotoxicity was higher in patients receiving four or more antituberculous drugs (50%) than in patients receiving three drugs (21%; P=0.03). Serum levels of cyclosporine decreased in the 26 patients under the simultaneous use of rifampin. Nine of them (35%) developed acute rejection, and five (56%) died, in comparison with 3 of 17 patients (18%) who did not develop rejection after the use of cyclosporine and rifampin (P=0.03). Although microbiological response was favorable in 94% of the 35 patients who completed 6 or more months of treatment, 16 other patients (31%) died before diagnosis or in the course of treatment. None of the patients treated for more than 9 months died as a consequence of tuberculosis, whereas the mortality rate was 33% among those treated for 6 to 9 months (P=0.03). Use of antilymphocyte antibodies or high doses of steroids for acute rejection before tuberculosis was associated with a higher mortality rate.

CONCLUSIONS

M tuberculosis causes serious and potentially life-threatening disease in solid-organ transplant recipients. Treatment with at least three drugs during 9 months or more, avoiding the use of rifampin, appears to be appropriate.

[Isotopic renogram after captopril administration: clinical experience in the assessment of the hypertensive patient]

BACKGROUND

Isotopic renogram allows renal function to be estimated in both kidneys independently. The glomerular filtrate in ischemic kidneys is largely dependent on the tone of the efferent glomerular arteriolae and therefore on the concentration of circulating angiotensin II.

METHODS

In 42 patients with severe high blood pressure in whom renal angiographic study was carried out for suspicion of vasculo-renal hypertension, an isotopic renogram using 99m Tc-DTPA as a tracer was performed in basal conditions and following the administration of 50 mg of oral captopril.

RESULTS

In 21 patients both the angiographic examination and the post-captopril renogram were normal. In 16 patients in whom uni or bilateral stenosis higher than 50% of the lumen of renal artery was observed on angiographic examination, the post-captopril renogram showed changes. In 5 patients the angiography was normal while the renogram showed evaluable changes. No false negatives were observed in the post-captopril renogram, however the basal renogram was not demonstrative in 6 patients with stenosis of the renal artery. Sensitivity of the test was thus 100% and specificity 80%. The positive predictive value was 76% and the negative predictive value 100%.

CONCLUSIONS

The post-captopril renogram may be a useful test in the functional study of renal behaviour in patients with vasculo-renal hypertension.

Transplant renography: 99m-Tc-DTPA versus 99m-Tc-MAG3. A preliminary note

99mTc-MAG3 has been proposed as a replacement for both 131I-hippuran and 99mTc-DTPA on clinical grounds. We undertook a prospective preliminary study to ascertain whether 99mTc-MAG3 works better than 99mTc-DTPA in the follow up of renal transplant recipients. Seventeen patients (21 renograms each MAG3 and DTPA) were studied, together, with a reference group of 10 patients in whom MAG3 and Hippuran clearance rates were determined simultaneously. As expected, 99mTc-MAG3 analog images were excellent and 99mTcMAG3 clearance correlated very well with 131I-hippuran clearance (r = 0.978). MAG3 values were 60% of hippuran values. However, when the corresponding renographic and perfusion findings were faced with different diagnostic challenges, such as post transplant renal failure and rejection, 99mTc MAG3 did not differ from 99mTc-DTPA in a significant way. 99mTc-DTPA was superior to 99mtc-MAG3 in one case of rejection.