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Background. After renal transplantation, patients are prone to develop impairments in glucose metabolism. In 2005, the American Diabetes Association published new guidelines on the diagnosis of pre-diabetes [plasma glucose levels from 100 to 125 mg/dL fasting or from 140 to 199 mg/dL 2 h after an oral glucose tolerance test (OGTT)]. This study sought to evaluate the prevalence and the potentially associated factors of pre-diabetes in a cohort of renal transplant patients on maintenance immunosuppressive medication. Furthermore, the diagnostic value of HbA1-c measurements in predicting pre-diabetes in transplant patients is undetermined. Methods. Two hundred consecutive renal transplant patients of our outpatient transplant clinic were evaluated using a standard OGTT. On the day of testing, multiple factors presumably associated with pre-diabetes were assessed via a standardized questionnaire: daily steroid dosage, triglyceride levels, cholesterol levels, estimated glomerular filtration rate (eGFR) [abbreviated Modification of Diet in Renal Disease (MDRD) formula], systolic and diastolic blood pressure, pulse pressure, age, gender, body mass index (BMI), BMI 30 and 25, number of renal transplants, number of rejection episodes prior to testing, source of renal transplant, cause of renal failure and medications as related to the prescription of cyclosporine, tacrolimus, mycophenolate mophetil, angiotensin-converting enzyme inhibitors, AT1-blockers, statins, β-blockers and thiazide diuretics. Patients diagnosed with pre-diabetes were compared to subjects with normal test results. Fishers exact test and the Wilcoxon rank-sum test were applied to compare the two study populations, whereas multivariate logistic regression was used to seek potential risk factors as related to other covariates. Risk ratios (RRs) to develop pre-diabetes were calculated for significant variables. Results. Ten patients had results indicative of post-transplant diabetes whereas data sets of three other patients were incomplete and were thus not included in the analysis. From the remaining 187 patients, 130 (69.5%) displayed normal test results whereas 57 (30.5%) had results indicative of pre-diabetes. On multivariate regression analysis, patients with pre-diabetes were significantly older {55.3 ± 12.1 versus 47.7 ± 12.6 years, P = 0.0007, RRs per 5 years increase 1.28 [95% confidence interval (95% CI) 1.11–1.47]}, had more rejection episodes [0.26 ± 0.48 versus 0.12 ± 0.37, P = 0.0024, RRs per rejection episode 3.99 (95% CI 1.63–9.77)] and showed lower diastolic blood pressure readings [77 ± 10 mmHg versus 81 ± 10 mmHg, P = 0.0362, RR per 5 mmHg decrease 1.14 (95% CI 1.04–1.49)]. Conclusions.. There is a high incidence of latent pre-diabetes among renal transplant recipients. Increasing age, rejection episodes and lower diastolic blood pressure proved to be associated with pre-diabetes. In contrast to post-transplant diabetes, tacrolimus use and HbA1-c levels were not prognostic of pre-diabetes.

Background. Impaired renal function has recently been reported in obstructive sleep apnoea (OSA). The underlying mechanisms, however, are not entirely understood. This study investigated the influence of mild-to-moderate OSA and its treatment on renal haemodynamics as assessed by the renal resistance index (RRI). Methods. RRI has been measured by colour duplex ultrasound in 64 patients with newly diagnosed mild-to-moderate OSA and 61 controls without OSA at baseline and follow-up after 9.9 months. Treatment with continuous positive airway pressure was offered to all patients with OSA (apnoea/hypopnoea index ≥ 5/h). Results. Increased values of RRI (≥ 1 SD [8.9%] above the age-adjusted normal value) were found in 41 out of 64 (64.0%) OSA patients when compared with 20 out of 61 (32.8%) controls (P < 0.001). The corresponding mean RRI was 70.50 ± 9.01 vs 66.51 ± 8.33 (P = 0.012). In multivariate analyses, the influence of OSA on RRI was independent from hypertension, diabetes mellitus, age and baseline renal function. At follow-up, RRI decreased only in patients with effective OSA treatment but remained unchanged in ineffectively treated OSA patients and controls. Conclusions. For the first time, this prospective controlled observational study demonstrates an impairment of renal haemodynamics in OSA as measured by an increased RRI. These changes of renal blood flow may identify OSA patients at high risk of declining renal function. Both parenchymal and vascular renal diseases are proposed as pathomechanisms for this association. An effective treatment of OSA resulted in a decreased RRI, suggesting an improvement in renal perfusion. Further studies are needed to elucidate the role of impaired renal haemodynamics in OSA.

Recently, a large international group of 25 investigators identified a candidate gene for hypertension which codes for phosducin (Pdc) as a novel player in the sympathetic nervous system [1]. In their study, a wide spectrum of findings documented its so-far unrecognized and apparently important role in experimental and human stress-induced hypertension. This conclusion is based on data ranging from detailed analyses of the sympathetic system in genetically manipulated Pdc �/� (knock-out) mice to the demonstration of its relevance in humans: in two separate cohorts, French Canadian and Afro-American individuals, respectively, a correlation was documented between singlenucleotide polymorphisms (SNPs) in the Pdc gene and stress-dependent blood pressure reactions. The target gene identified by the investigators codes for the G-protein regulator phosducin. In mice, targeted Pdc deletion increased blood pressure, increased catecholamine turnover in the peripheral sympathetic system and prolonged action potential firing. This finding suggests that Pdc is a hypotensive principle, explaining why reduced function of Pdc amplifies the hypertensive reaction to stressors. In other words: Pdc puts a brake on sympathetic activity, and conversely Pdc malfunction will lead to hypertension. What is the site of action of Pdc? The Pdc gene and the Pdc protein are expressed in sympathetic ganglia, although to a much lower extent than in the retina and pineal gland, but not in heart, blood vessels and kidney, important players in blood pressure control. To identify the site of action, experimental manipulations sequentially excluded changes in heart function, vascular function or function of the central nervous system as candidates. Early in life, cardiac morphology was not altered in Pdc�/�mice,butleftventricularcontractilitywasincreased despite no change of sensitivity to adrenoceptor agonists (norepinephrine, dobutamine)—consistent with increased sympathetic nerve traffic. In older animals (>4 months), however, significant hypertrophy was seen with expression of fetal genes as evidence of target organ injury.

Vitamin D has emerged as an important survival factor in patients with chronic kidney disease. Non-activated vitamin D may also have beneficial effects on bone, cardiovascular and immune functions. Cholecalciferol is the prevalent non-activated vitamin D in Europe, but there is no valid prospective data available about its use in haemodialysis patients. Thus, we initiated a prospective study to evaluate dosing, safety and tolerability of cholecalciferol supplementation in haemodialysis patients.The prospective study included 64 haemodialysis patients. During replenishment phase patients received 20 000 IU cholecalciferol/week for 9 months. In the open maintenance phase (15 months), patients were randomized to a treated group (20 000 IU cholecalciferol/month) and an untreated group, which did not receive cholecalciferol.Calcidiol [25(OH)D] deficiency (37.5 nmol/l;15 microg/l) was detected in 61/64 patients (95%). During the replenishment phase, calcidiol increased significantly from 16.65 +/- 9.6 to 79.48 +/- 27.15 nmol/l (6.66 +/- 3.84 microug/l to 31.79 +/- 10.86 microg/l) (P0.001). Recommended levels (75 nmol/l;30 microg/l; K/DOQI) were achieved in 57% of patients. Calcium increased from 2.28 +/- 0.17 to 2.37 +/- 0.19 mmol/l (9.1 +/- 0.69 mg/dl to 9.49 +/- 0.75 mg/dl) (P0.01). Phosphorus, calcium-phosphorus product and parathyroid hormone showed no significant changes. Fifty-nine patients progressed to the maintenance phase. Analysis per protocol showed a significant drop of calcidiol in the treated [83.98 +/- 31.73 versus 78.5 +/- 38.75 nmol/l (33.59 +/- 12.69 versus 31.4 +/- 15.5 microg/l) (P0.001)] and untreated groups [86.35 +/- 40.75 versus 53.4 +/- 26.2 nmol/l (34.54 +/- 16.3 versus 21.36 +/- 10.48 microg/l) (P0.001)]. The comparison of the treated and the untreated groups showed no significant differences at the beginning of the maintenance phase: 83.98 +/- 31.73 versus 86.35 +/- 40.75 nmol/l (33.59 +/- 12.69 versus 34.54 +/- 16.3 microg/l). At the end they differed significantly: 78.5 +/- 38.75 versus 53.4 +/- 26.2 nmol/l (31.4 +/- 15.5 versus 21.36 +/- 10.48 microg/l) (P0.001).Vitamin D deficiency is present in a majority of haemodialysis patients. Supplementation with cholecalciferol is safe, well tolerated and reasonable to replenish vitamin D stores in haemodialysis patients. However, only 57% of patients achieved recommended calcidiol levels, thus favouring additional dose-finding studies.

Background. The introduction of sirolimus as an immunosuppressive drug for renal transplantation has lead to an increase of unexplained interstitial pneumonitis. Methods. Out of a cohort of 115 patients receiving sirolimus for prophylaxis of renal and/or pancreas transplant rejection, 11 patients with interstitial pneumonitis were identified. Medical records and published case series were reviewed to identify risk factors associated with the occurrence of pneumonitis. Results. Eleven out of 80 patients (14%) with late switch to sirolimus developed pneumonitis, in contrast to none of the 35 patients with de novo use of sirolimus. The mean sirolimus trough level at presentation was 16.7mg/l (range: 6.2–38.7mg/l). Glomerular filtration rate (GFR) was significantly lower in patients with pneumonitis compared to controls (mean 21.3 � 3.9 ml/min vs 38.65 � 2.14 ml/min P ¼ 0.002). Two patients needed haemodialysis shortly before pneumonitis was diagnosed. In a multivariate analysis only serum creatinine and GFR were independent predictors for pneumonitis. Sirolimus was discontinuated in five patients and the dose reduced in the other patients. Pneumonitis resolved within 14–28 days in all patients. One patient who had continued low-dose sirolimus treatment relapsed after 5 months, the other five patients had no relapse over a period of 15–48 months. Pooled analysis of our data and other published case series showed that the frequency of pneumonitis in patients with de novo use of sirolimus is significantly lower than in patients with late switch [5/133 (4%) vs 46/326 (14%) patients, P ¼ 0.0024]. Conclusions. Late switch to sirolimus and impaired renal function are risk factors for pneumonitis. A sirolimus blood trough level above 12mg/l may increase the risk, but pneumonitis may also occur at blood trough levels as low as 6mg/l. Since pneumonitis may recur during low-dose sirolimus treatment, discontinuation of sirolimus appears to be the safest treatment option.

150 mmol/l, potassium (K+) 3.6 mmol/l and chloride(Cl−) 126.3 mmol/l. The anion gap (Na+−(HCO3−A 70-year-old man was admitted with pronounced +Cl−)) was increased (20 mmol/l). Blood urea wasdyspnoea and a 2 week history of progressively 201 mg/dl, and creatinine 1.0 mg/dl. Haemoglobin,worsening diarrhoea and diminished urinary volume. white blood cell count, platelet count, C-reactive pro-The diarrhoea was described as watery stools without tein, aminotransferases, phosphate, lactate, and bloodblood or mucus and was not ameliorated by loperam- sugar were normal. Stool cultures were negative.ide. Anuria developed 2 days before admission. Fever, Urinanalyses were not performed because of anuria.nausea, and abdominal or flank pain were absent. Ultrasonography showed an empty bladder with noIn 1995 the patient had undergone abdominoperineal signs of hydronephrosis; however, fluid-filled loops ofrectum resection and sigmoid colostomy as treatment bowel were visualized. A cystogram revealed a largefor non-metastatic adenocarcinoma of the distal fistulous tract between the urinary bladder and smallrectum with an intermediate stage of diVerentiation intestine (Figure 1).(pT3N3M0, R0-resection). The patient received com- The patient received fluid substitution, bicarbonatebined adjuvant treatment with pelvic radiotherapy and potassium infusions, and surgical treatment was(total dose 50.4 Gy delivered in a fractionated fashion) planned. Two days later the diarrhoea ceased and urineand 5-fluoruracil chemotherapy. Urinary retention due flowed through the bladder catheter. The acidosis andto neurological damage, as assessed by cystometry, uraemia reversed rapidly. Surgical treatment withdeveloped as a complication of surgery. The patient excision of the fistula and direct closure was performed.performed intermittent self-catheterization three times Microscopic examination of the fistulous tract revealeda day. Two years later an abdominal computed tomo- late-stage radiation injury with signs of chronicgraphy scan showed evidence of local recurrence and inflammation and vascular damage with intimal fib-metastatic disease in the liver. Palliative therapy with rosis. No signs of malignancy were detected.endotoxin (

It is generally accepted that hypertension and pro- arises whether, in analogy to the message from the teinuria are the two most important progression factors ELITE study, Ang II receptor blockers are superior to in chronic renal failure [1]. Antihypertensive drugs ACE inhibitors in renal failure as well. Some points slow progression, and this has been attributed mainly relating to these issues will be discussed here. to their blood-pressure-lowering eVect. It is generally agreed, however, that in various types of chronic renal failure [2‐4] angiotensin-converting enzyme (ACE) Sympathetic control of heart and kidney