Pathomechanisms and the diagnosis of arterial hypertension in pediatric renal allograft recipients

Is low birth weight an additional risk factor for hypertension in paediatric patients after kidney transplantation?

Hypertension (HTN) remains a common complication after kidney transplantation among paediatric patients. Although low birth weight (LBW) has been implicated as an important risk factor for cardiovascular diseases, its effect on transplantation patients has not yet been addressed. It is essential to determine whether children with LBW who undergo transplantation are more likely to develop post-transplantation HTN. For this study, the medical records of 96 kidney recipients were retrospectively examined. A total of 83 patients fulfilled the inclusion criteria. Overall, post-transplantation HTN was observed in 54% of the recipients. Multivariate logistic regression revealed that time from transplantation >14 months (odds ratio (OR) 3.6; 95% confidence interval (CI) 1.31–10.06; P = 0.013), current CKD (OR 2.6; 95% CI 1.01–7.20; P = 0.045), presence of LBW (OR 3.6; 95% CI 1.04–12.32; P = 0.044) and current overweight/obesity (OR 3.7; 95% CI 1.02–13.91; P = 0.047) were associated with post-transplantation HTN. In conclusion, our data provide evidence for the first time that LBW is a significant predictive factor in the development of post-transplantation HTN. This finding has important clinical implications as it serves to alert clinicians about this additional risk factor in paediatric patients undergoing kidney transplant.

Factors associated with cardiovascular target organ damage in children after renal transplantation

BACKGROUND

Cardiovascular disease is the second-most common cause of death in pediatric renal transplant recipients. The aim of this study was to evaluate subclinical cardiovascular target organ damage defined as the presence of arterio- and atherosclerotic lesions and cardiac remodeling and to analyze contributing risk factors in a large cohort of children after renal transplantation (RT).

METHODS

A total of 109 children aged 13.1 ± 3.3 years who had undergone RT at one of three German transplant centers were enrolled in this study. Patients had been transplanted a mean of 5.5 (±4.0) years prior to being enrolled in the study. Anthropometric data, laboratory values and office- and 24-h ambulatory blood pressure monitoring (ABPM) were evaluated. Cardiovascular target organ damage was determined through non-invasive measurements of aortic pulse wave velocity (PWV), carotid intima-media thickness (IMT) and left ventricular mass (LVM).

RESULTS

Elevated PWV or IMT values were detected in 22 and 58% of patients, respectively. Left ventricular hypertrophy was found in as many as 43% of patients. The prevalence of uncontrolled or untreated hypertension was 41%, of which 16% of cases were only detected by ABPM measurements. In the multivariable analysis, higher diastolic blood pressure, everolimus intake and lower estimated glomerular filtration rate were independently associated with high PWV. Higher systolic blood pressure and body mass index were associated with elevated LVM.

CONCLUSIONS

Our results showed an alarming burden of cardiovascular subclinical organ damage in children after RT. Hypertension, obesity, immunosuppressive regimen and renal function emerged as independent risk factors of organ damage. Whereas the latter is not modifiable, the results of our study strongly indicate that the management of children after RT should focus on the control of blood pressure and weight.

Clinical Characteristics of Transplant-associated Encephalopathy in Children

We aimed to analyze characteristics of encephalopathy after both hematopoietic stem cell and solid organ pediatric transplantation. We retrospectively reviewed medical records of 662 pediatric transplant recipients (201 with liver transplantation [LT], 55 with heart transplantation [HT], and 67 with kidney transplantation [KT], 339 with allogeneic hematopoietic stem cell transplantation [HSCT]) who received their graft organs at Asan Medical Center between January 2000 and July 2014. Of the 662 patients, 50 (7.6%) experienced encephalopathy after transplantation. The incidence of encephalopathy was significantly different according to the type of organ transplant: LT, 16/201 (8.0%), HT, 13/55 (23.6%), KT, 5/67 (7.5%), and HSCT, 16/339 (4.7%) (P < 0.001). Drug-induced encephalopathy (n = 14) was the most common encephalopathy for all transplant types, but particularly after HSCT. Hypertensive encephalopathy was the most common after KT and HT, whereas metabolic encephalopathy was the most common after LT. The median time to encephalopathy onset also differed according to the transplant type: 5 days after KT (range 0-491 days), 10 days after HT (1-296 days), 49.5 days after HSCT (9-1,405 days), and 39 days after LT (1-1,092 days) (P = 0.018). The mortality rate among patients with encephalopathy was 42.0% (n = 21/50). Only 5 patients died of neurologic complications. Transplant-associated encephalopathy presented different characteristics according to the type of transplant. Specialized diagnostic approach for neurologic complications specific to the type of transplant may improve survival and quality of life in children after transplantation.

Serum Endocan Levels Associated with Hypertension and Loss of Renal Function in Pediatric Patients after Two Years from Renal Transplant

Endocan is an important biomarker of inflammation and endothelial dysfunction that increases in association with several chronic diseases. Few published data have described the role of endocan in pediatric renal transplant (RT) patients. We evaluated the endocan concentrations in 62 children who underwent renal transplantation and assessed their relationships with the patients' blood pressure and loss of renal function. The endocan levels were significantly elevated in the pediatric RT patients who had hypertension and a loss of renal function. We determined positive correlations between the endocan concentrations and the hemodynamic variables (systolic blood pressure: r = 0.416; P = 0.001; pulse pressure: r = 0.412; P = 0.003). The endocan levels were inversely correlated with the estimated glomerular filtration rate (r = −0.388; P = 0.003). An endocan cutoff concentration of 7.0 ng/mL identified pediatric RT patients who had hypertension and a loss of renal function with 100% sensitivity and 75% specificity. In conclusion, the endocan concentrations were significantly elevated in pediatric RT patients who had both hypertension and a loss of renal function. The correlations between the endocan levels and the hemodynamic variables and the markers of renal function strengthen the hypothesis that it is an important marker of cardiorenal risk.

Ambulatory Blood Pressure Monitoring and Echocardiographic Findings in Renal Transplant Recipients

Hypertension is common in renal transplant recipients (RTRs). Ambulatory blood pressure (BP) monitoring (ABPM) is important in diagnosing hypertension and diurnal BP variation. The authors set out to compare office BP and ABPM measurements to determine diurnal pattern and to evaluate echocardiographic findings in RTRs. ABPM and office BP measurements were compared in 87 RTRs. Echocardiographic evaluation was performed for each patient. The correlations between office and 24-hour ABPM were 0.275 for mean systolic BP (P=.011) and 0.260 for mean diastolic BP (P=.017). Only 36.8% had concordant hypertension between office BP and ABPM, with a masked hypertension rate of 16.1% and white-coat effect rate of 24.1%. Circadian BP patterns showed a higher proportion of nondippers (67.8%). Left ventricular mass index was increased in 21.8% of all recipients. There was a significant but weak correlation between office BP and ABPM.

Cardiovascular risk factors in children after kidney transplantation--from short-term to long-term follow-up

Cardiovascular-related mortality is 100-fold higher in pediatric renal transplant recipients than in the age-matched general population. Seventy-seven post-renal transplant children's charts were reviewed for cardiovascular risk factors at two and six months after transplantation (short term) and at two yr after transplantation and the last follow-up visit (mean 7.14 ± 3.5 yr) (long term). Significant reduction was seen in cardiovascular risk factors prevalence from two months after transplantation to last follow-up respectively: Hypertension from 52.1% to 14%, hypercholesterolemia from 48.7% to 33%, hypertriglyceridemia from 50% to 12.5%, anemia from 29.6% to 18.3%, hyperparathyroidism from 32% to 18.3% and hyperglycemia from 11.7% to 10%, and left ventricular hypertrophy from 25.8% at short term to 15%. There was an increase in the prevalence of obesity from 1.5% to 3.9% and of CKD 3-5 from 4.75% to 24%. The need for antihypertensive treatment decreased from 54% to 42%, and the percentage of patients controlled by one medication rose from 26% to 34%, whereas the percentage controlled by 2, 3, and 4 medications decreased from 21.9%, 5.5%, and 1.4% to 6%, 2%, and 0. Children after renal transplantation appear to have high rates of cardiovascular risk factors, mainly on short-term follow-up.

Management of hypertension and factors affecting its control in Jordanian renal transplant recipients

BACKGROUND

Hypertension affects 70-90 % of all kidney transplant recipients. It is associated with poor graft survival and is a contributing factor to the increased cardiovascular mortality. The reasons for the insufficient blood pressure control in transplanted patients have not been thoroughly investigated.

OBJECTIVE

To evaluate the extent of blood pressure control in Jordanian hypertensive renal transplant recipients and to assess factors associated with such control.

SETTING

Three outpatient renal transplant clinics in Amman.

METHOD

A cross-sectional observational study including 181 patients. We have considered blood pressure <130/80 mm Hg as controlled hypertension. Bivariate and multivariate logistic regression analyses were used to determine clinical factors associated with achievement of blood pressure control.

MAIN OUTCOME MEASURES

Proportion of patients who achieved hypertension control and clinical factors associated with good blood pressure control.

RESULTS

Mean systolic blood pressure was 128.6 ± 16.3 mm Hg and mean diastolic blood pressure was 82.8 ± 11.5 mm Hg. Blood pressure control was achieved only in 58 % of patients. The most commonly prescribed antihypertensives were calcium channel blockers (58 %) followed by beta-blockers (44 %). In bivariate analysis, female gender (p = 0.017) and creatinine clearance (p = 0.002) were positively associated, while number of antihypertensive medications was inversely associated (p = 0.04) with achievement of blood pressure control. After including these factors in multivariate logistic regression analysis, only creatinine clearance remained independently associated with hypertension control (odds ratio, OR 1.04; 95 % confidence interval [CI] 1.01-1.06; p = 0.003).

CONCLUSION

Blood pressure control among renal transplant recipients in Jordan was found to be inadequate. The only factor found to be independently associated with adequate blood pressure control was creatinine clearance.

Pharmacology of immunosuppressive medications in solid organ transplantation

The multitude of immunosuppressants available for solid organ transplantation allows for many combinations of immunosuppressive therapies that can be tailored to a patient’s specific lifestyle and immunosuppression needs. Newer agents currently being studied offer even more possibilities for the future to further reduce the incidence of acute rejection and prolong graft and patient survival.

Blood pressure profile in renal transplant recipients and its relation to diastolic function: tissue Doppler echocardiographic study

Hypertension is a common complication after renal transplantation and is associated with increased risk of cardiovascular disease. The aim of the current study was to investigate the diurnal blood pressure pattern and its relation to structural and functional cardiac changes in renal transplant recipients. Sixty-six stable renal transplant patients (34 female, 32 male), aged 7 to 25 years (mean 17.4±4.3 years) were enrolled in this study. Cardiac function assessed by tissue Doppler echocardiography and blood pressure measurement performed using both the ambulatory and the casual method. Hypertension was demonstrated in 57% of recipients by the casual method and in 75.7% by ambulatory blood pressure monitoring (ABPM). The efficacy of BP control among patients on antihypertensive drugs was 60%. The prevalence of non-dipping was 73%. There was significant inverse correlation between systolic or diastolic day-time or night-time BP index and post-transplant duration (p<0.001, r=-0.386), but no correlation between ABP parameters and BMI, gender, and eGFR. There was a significant relationship between all ABP parameters and left ventricular mass index (LVMI) (p=0.025-0.007, r=0.28-0.38). LVMI was significantly higher in hypertensive than in normotensive cases (p=0.034). There was no difference in diastolic function between hypertensive and normotensive patients or between patients with and without left ventricular hypertrophy (LVH). In conclusion, our study showed the advantage of ABPM over the casual method of diagnosis of hypertension. LVH is common in transplant patients and is likely associated with arterial hypertension. Hypertension and LVH cannot differentiate transplant patients with diastolic malfunction.

Adverse effects of immunosuppression in pediatric solid organ transplantation

Solid organ transplantation is a life-saving treatment for end-stage organ failure in children. Immunosuppressant medications are used to prevent rejection of the organ transplant. However, these medications are associated with significant adverse effects that impact growth and development, quality of life (QOL), and sometimes long-term survival after transplantation. Adverse effects can differ between the immunosuppressants, but many result from the overall state of immunosuppression. Strategies to manage immunosuppressant adverse effects often involve minimizing exposure to the drugs while balancing the risk for rejection. Early recognition of immunosuppressant adverse effects may help to reduce morbidities associated with solid organ transplantation, improve QOL, and possibly increase overall patient survival.

Treatment strategies to minimize or prevent chronic allograft dysfunction in pediatric renal transplant recipients: an overview

Long-term allograft survival poses a major problem in pediatric renal transplantation, with allograft nephropathy being the principal cause of graft failure after the first post-transplant year. The mechanisms of nephron loss resulting in graft dysfunction are multiple, comprising both immunologic factors such as acute and chronic antibody- or T-cell-mediated rejection and non-immunologic components. The latter include peri-transplant injuries and renovascular lesions (renal artery stenosis, thrombosis) as well as cardiovascular risk factors such as arterial hypertension and hyperlipidemia. Another relevant issue leading to progressive nephron loss and declining kidney transplant function is acute and chronic nephrotoxicity induced by the calcineurin inhibitors (CNIs) ciclosporin (cyclosporine microemulsion) and tacrolimus. Furthermore, the presence of an abnormal lower urinary tract as well as bacterial (recurrent pyelonephritis) and viral (cytomegalovirus [CMV], polyomavirus [BK virus; BKV]) infections are crucial factors involved in the incidence of chronic allograft dysfunction and graft failure. Renovascular lesions and lower urinary tract obstruction are typical indicators for surgical intervention. The aim of treatment in pediatric patients with renal failure secondary to a dysfunctional lower urinary tract is to create a sterile, continent, and nonrefluxive reservoir. Surgical techniques such as bladder augmentation and the introduction of intermittent catheterization and anticholinergic therapy have significantly improved graft outcome. Arterial hypertension, another factor responsible for graft function deterioration in pediatric renal transplant recipients, is controlled preferably by the use of angiotensin converting enzyme (ACE) inhibitors or angiotensin II receptor antagonists, which are known to possess nephroprotective properties in addition to their potent antihypertensive effects. Although treatment of subclinical rejection with augmented immunosuppression has been associated with better graft survival, an increase of the immunosuppressive level to avoid subclinical rejection should be weighed against the risk of infection. The majority of viral infections affecting kidney allografts are caused by CMV and BKV. Antiviral CMV prophylaxis or pre-emptive therapy with ganciclovir has been shown to have beneficial effects in the pediatric renal transplant population. Treatment of BKV-induced nephropathy is based on reduction of the immunosuppressant therapy, although specific antiviral agents such as cidofovir and leflunomide are known to inhibit BKV. However, cidofovir itself is nephrotoxic and should therefore be administered cautiously to pediatric renal transplant patients. Since CNIs are likewise known for their nephrotoxic effects, especially with long-term use, alteration of the immunosuppressant regimen is necessary in case of deteriorating graft function due to CNI-induced histopathologic changes. Complete CNI avoidance seems inappropriate because, in this situation in pediatric renal transplant recipients, other relatively potent immunosuppressant agents such as lymphocyte-depleting antibodies, which are frequently accompanied by a higher incidence of infections, are needed for rejection prophylaxis. CNI withdrawal and switching of the immunosuppressant regimen from CNI therapy to sirolimus may be an option for some pediatric renal transplant patients with less advanced graft function deterioration. Nevertheless, potential adverse events such as aggravation of proteinuria, hyperlipidemia, myelosuppression, and hypergonadotropic hypogonadism have to be considered, and controlled studies are lacking. At present, an immunosuppressant maintenance therapy composed of low-dose tacrolimus or ciclosporin (CNI minimization) and mycophenolate mofetil with low-dose corticosteroids appears to be the most promising strategy to adopt in pediatric renal transplant recipients at low or normal immunologic risk.

Hypertension after renal transplantation

Hypertension is a common and serious complication after renal transplantation. It is an important risk factor for graft loss and morbidity and mortality of transplanted children. The etiology of posttransplant hypertension is multifactorial: native kidneys, immunosuppressive therapy, renal-graft artery stenosis, and chronic allograft nephropathy are the most common causes. Blood pressure (BP) in transplanted children should be measured not only by casual BP (CBP) measurement but also regularly by ambulatory BP monitoring (ABPM). The prevalence of posttransplant hypertension ranges between 60% and 90% depending on the method of BP measurement and definition. Left ventricular hypertrophy is a frequent type of end-organ damage in hypertensive children after transplantation (50-80%). All classes of antihypertensive drugs can be used in the treatment of posttransplant hypertension. Hypertension control in transplanted children is poor; only 20-50% of treated children reach normal BP. The reason for this poor control seems to be inadequate antihypertensive therapy, which can be improved by increasing the number of antihypertensive drugs. Improved hypertension control leads to improved long-term graft and patient survival in adults. In children, there is a great potential for antihypertensive treatment that could also result in improved graft and patient survival.

Urinary tract infections in children after renal transplantation

Urinary tract infections (UTI) after pediatric kidney transplantation (KTX) are an important clinical problem and occur in 15-33% of patients. Febrile UTI, whether occurring in the transplanted kidney or the native kidney, should be differentiated from afebrile UTI. The latter may cause significant morbidity and is usually associated with acute graft dysfunction. Risk factors for (febrile) UTI include anatomical, functional, and demographic factors as well as baseline immunosuppression and foreign material, such as catheters and stents. Meticulous surveillance, diagnosis, and treatment of UTI is important to minimize acute morbidity and compromise of long-term graft function. In febrile UTI, parenteral antibiotics are usually indicated, although controlled data are not available. As most data concerning UTI have been accumulated retrospectively, future prospective studies have to be performed to clarify pathogenetic mechanisms and risk factors, improve prophylaxis and treatment, and ultimately optimize long-term renal graft survival.

Blood pressure control in hypertensive pediatric renal transplants: role of repeated ABPM following transplantation

BACKGROUND

Hypertension in pediatric renal transplants is a widespread condition associated with high mortality risk in early adult life. Ambulatory blood pressure monitoring (ABPM) was found to be superior to office blood pressure (BP) in identifying true hypertensive and responders to treatment. The aim of this study was to investigate the role of repeated ABPM, performed at yearly intervals following transplantation, in the assessment and decision-making processes of post-transplant hypertension.

METHODS

Thirty-seven recipients (23 males; aged 10.5 +/- 4.3 years) who were followed for 4.3 +/- 2.2 years (range 2-9) after transplantation were eligible for analysis. The mean follow-up time between the baseline (1 year post-transplantation) and the most recent ABPM examination was 3.3 +/- 2.2 years (range 1-8).

RESULTS

Throughout the follow-up period, antihypertensive therapy was either started or intensified in 27 recipients. These interventions were decided based on ABPM results obtained on 40 of 44 occasions. At last follow-up, 24 of 29 treated hypertensive recipients displayed controlled BP. This figure was significantly higher compared to our historical hypertensive control recipients in whom ABPM was applied for the first time in treatment at 6 +/- 3.3 years (range 2-15) after transplantation, while therapeutic decisions were driven by office BP measurements (95 % confidence interval (95% CI) for the difference between proportions (80.6-32 %) 36-60 %, P = 0.001).

CONCLUSIONS

Our study shows that, in a population with high risk for hypertension, repeated ABPM may significantly help to improve BP control.

Prospective analysis of carotid arterial wall structure in pediatric renal transplants with ambulatory normotension and in treated hypertensive recipients

Increased carotid IMT was found to be associated with cardiovascular risk factors. As pediatric renal transplants are at high risk for cardiovascular disease, we examined whether there is a relationship between BP and IMT in normotensive and in treated hypertensive recipients after transplantation. Thirty-one recipients aged 10 +/- 3.5 yr (16 M, 15 F) underwent repeated carotid ultrasound examinations 5.4 +/- 3.2 yr after transplantation with a 4.1 +/- 1 yr interval and were followed with annual ambulatory BP monitoring. Baseline IMT was significantly higher in transplants compared with controls. When recipients were again investigated, follow-up IMT measurements were similar compared with measurements obtained at baseline. The analysis of variance showed that baseline IMT both in recipients with strict normotension, i.e., ambulatory normotension without antihypertensive therapy at baseline and throughout the study period (n = 9), and in recipients with treated hypertension or newly diagnosed hypertension (n = 22) was significantly higher than in healthy controls (n = 21). Baseline IMT did not differ between these subgroups of recipients. Similarly, pairwise comparisons showed that baseline and follow-up IMT within each subgroup of recipients were not significantly different. Overall and regardless of time-point, no significant associations were found between systolic and diastolic 24-h BP, daytime BP, night-time BP, ambulatory BP standard deviation scores, BP loads and IMT. Our results suggest that increased IMT in pediatric renal transplants does not seem to be related to BP but more likely to other factor(s) not investigated in this study.

Improved control of hypertension in children after renal transplantation: results of a two-yr interventional trial

Hypertension is a frequent complication in children after renal transplantation and the control of post-transplant hypertension is unsatisfactorily low. The aim of this prospective interventional study was to improve the control of hypertension in children after renal transplantation. Thirty-six children fulfilled the inclusion criteria (> or =6 months after transplantation and no acute rejection in the last three months). BP was measured using ABPM. Hypertension was defined as mean ambulatory BP > or =95th-centile for healthy children and/or using antihypertensive drugs. The study intervention consisted of using intensified antihypertensive drug therapy - in children with uncontrolled hypertension (i.e., mean ambulatory BP was > or =95th centile in treated children), antihypertensive therapy was intensified by adding new antihypertensive drugs to reach goal BP <95th centile. ABPM was repeated after 12 and 24 months. Daytime BP did not change significantly after 12 or 24 months. Night-time BP decreased from 1.57 +/- 1.33 to 0.88 +/- 0.84 SDS for systolic and from 1.10 +/- 1.51 to 0.35 +/- 1.18 SDS for diastolic BP after 24 months (p < 0.05). The number of antihypertensive drugs increased from 2.1 +/- 0.9 to 2.7 +/- 0.8 drugs per patient (p < 0.05), this was especially seen with the use of ACE-inhibitors (increase from 19% to 40% of children, p < 0.05). In conclusion, this interventional trial demonstrated that, in children after renal transplantation, the control of hypertension, especially at night-time, can be improved by increasing the number of antihypertensive drugs, especially ACE-inhibitors.

ABPM vs office blood pressure to define blood pressure control in treated hypertensive paediatric renal transplant recipients

While 24-h ambulatory blood pressure monitoring (ABPM) is an established tool for monitoring antihypertensive therapy in adults, data in children are scarce. We retrospectively analysed whether office blood pressure (BP) is reliable for the diagnosis of BP control in 26 treated hypertensive paediatric renal transplants. Controlled office BP was defined as the mean of three replicate systolic and diastolic BP recordings less than or equal to the 95th age-, sex- and height-matched percentile on the three-outpatient visits closest to ABPM. Controlled ABPM was defined as systolic and diastolic daytime BP < or =95th distribution adjusted height- and sex-related percentile of the adapted ABPM reference. Eight recipients (30%) with controlled office BP were in fact categorized as having non-controlled BP by ABPM criteria. Overall, when office BP and ABPM were compared using the Bland and Altman method, the 95% limits of agreement between office and daytime values ranged from -12.6 to 34.1 mmHg for systolic and -23.9 to 31.7 mmHg for diastolic BP, and the mean difference was 10.7 and 3.9 mmHg respectively. Office readings miss a substantial number of recipients who are hypertensive by ABPM criteria. Undertreatment of hypertension could be avoided if ABPM is applied as an adjunct to office readings.

Control of hypertension in children after renal transplantation

The aim of this cross-sectional single-center study was to investigate the efficacy of hypertension control in children who underwent transplantation using ambulatory blood pressure (BP) monitoring, and to determine the risk factors associated with poor control of hypertension. Thirty-six children fulfilled the inclusion criteria. The mean age was 13.9+/-4.4 yr; the mean time after renal transplantation was 2.7+/-2.4 yr (0.5-10.1). Hypertension was defined as a mean ambulatory BP > or =95th centile for healthy children and/or requiring antihypertensive drugs. Hypertension was regarded as controlled if the mean ambulatory BP was <95th centile in children already on antihypertensive drugs, or uncontrolled if the mean ambulatory BP was > or =95th centile in treated children. Hypertension was present in 89% of children. Seventeen children (47%) had controlled hypertension, and 14 (39%) had uncontrolled hypertension. One child (3%) had untreated hypertension, and only four children (11%) showed normal BP without antihypertensive drugs. The efficacy of hypertensive control was 55% (17 of 31 children on antihypertensive drugs had a BP<95th centile), i.e. 45% of treated children still had hypertension. Children with uncontrolled hypertension had significantly higher cyclosporine doses (6.1 vs. 4.3 mg/kg/day, p=0.01) and tacrolimus levels (9.2 vs. 6.1 microg/L, p<0.05), and there was a tendency toward use of lower number of antihypertensive drugs (2.0 vs. 1.5 drugs/patient, p=0.06) and lower use of angiotensin-converting enzyme (ACE) inhibitors (7 vs. 35%, p=0.09) and diuretics (29 vs. 59%, p=0.14) than in children with controlled hypertension. In conclusion, nearly 90% of our children after renal transplantation are hypertensive and the control of hypertension is unsatisfactorily low. The control of hypertension could be improved by increasing the number of prescribed antihypertensive drugs, especially ACE inhibitors, and diuretics, or by using higher doses of currently used antihypertensives.

Potential cardiovascular risk factors in paediatric renal transplant recipients

Cyclosporin (CsA) therapy is associated with side effects such as hypertension, hyperlipidemia and nephrotoxicity. Tacrolimus (Tac) has been shown to be more favourable in this respect. We retrospectively analysed office blood pressure (BP), serum total cholesterol (TC) and fasting glucose levels, and estimated graft function profiles in paediatric (n =56) and young adult (n =14) renal transplant recipients whose maintenance immunosuppressive regimen was based upon CsA (n =38) or Tac (n =32) given with mycophenolate mofetil and corticosteroids. The analysis was performed at four different time-points: at 1, 6, 12, and 24 months post-transplant, respectively. Baseline characteristics were comparable between treatment groups. Differences for both systolic and diastolic BP, and graft function between treatment groups became significant from month 1 and throughout the 2-year period. Values (mean +/- SD) for CsA-treated and Tac-treated recipients at 2 years were 118.8+/-11.1 / 74.6+/-7.4 mmHg vs 109.3+/-11.2 / 67.2+/-7.8 mmHg for systolic and diastolic BP, respectively, p <0.005/0.005; and 72.0+/-18.5 ml/min vs 84.0+/-22.4 ml/min per 1.73 m(2) for graft function, respectively, p <0.01. Office hypertension, defined as the use of antihypertensive medication at month 24, was significantly associated with CsA-therapy (chi(2), p <0.01). TC levels became significantly lower at months 6, 12, and 24 in the Tac group compared with the CsA group. Hypercholesterolemia, defined as TC>or=200 mg/dl, was significantly associated with CsA-based immunosuppressive regimen at months 6, 12, and 24 post-transplant (chi(2), p <0.05, p <0.001, and p <0.01, respectively). Although Tac therapy was associated with higher glucose levels, no recipient developed post-transplant diabetes mellitus. The number of recipients who experienced acute rejections was comparable in both groups. In conclusion, Tac-based immunosuppressive therapy was found to be associated with more favourable potential risk-factor profiles for cardiovascular disease and better graft function at 2 years post-transplant compared with CsA-therapy.