Benefits of accurate and guided endoureterotomy versus ureteral balloon dilatation in the management of ureteral strictures-comparative animal study

Background

Endoscopic treatment of ureteral strictures provides a minimally invasive approach with a shorter hospital stay and less postoperative pain. There are different therapeutic options, the dilatation balloon and endoureterotomy with holmium yttrium-aluminum-garnet (Ho:YAG) laser are the most used. To assess histological changes after endoureterotomy in the ureteral stricture treatment comparing Ho:YAG laser endoureterotomy versus balloon dilatation endoureterotomy.

Methods

The subjects used were a total of 48 female pigs. The initial assessment consisted of an endoscopic, nephrosonographic, and contrast fluoroscopic evaluation of the urinary tract. Subsequently, a model of ureteral stricture was performed. Three weeks later, the ureteral stricture was diagnosed and treated. Then animals were randomly assigned to two groups (group A, Balloon dilatation endoureterotomy and group B, Holmium laser retrograde endoureterotomy) in which a double-pigtail ureteral stent was placed for 3 weeks. Follow-up assessments were performed at 3-6 weeks. The final follow-up was completed at 5 months and included the pathological study.

Results

In terms of therapeutic effectiveness, the overall success was 81.2%. The success rate was 91.7% in group B and 70.8%in group A without statistical significance. No evidence of vesicoureteral reflux nor urinary tract anomalies were observed. Histological assessment showed statistical significance in overall score, lamina propria fibrosis and serosal alterations in group A with higher histological changes.

Conclusions

The overall histopathological score after ureteral stricture treatment in an animal model showed better remodeling of incised ureteral wall healing after Ho:YAG laser endoureterotomy. Laser endoureterotomy tends to have higher success rate compared to balloon dilatation.

Complicated diverticulitis in kidney transplanted patients: analysis of 717 cases

INTRODUCTION

This study aims to investigate possible risk factors for diverticulitis in kidney transplant recipients affected by colonic diverticulosis.

METHODS AND RESULTS

We investigated 717 patients transplanted between 2000 and 2010. Diverticular disease was endoscopically diagnosed in 17 of 717 examined patients. Eight patients were diagnosed with autosomal dominant polycystic kidney disease (ADPKD); 9 of 17 patients underwent emergency surgery. We performed Hartmann's procedure on all patients, with a second stage performed at least 6 months later.

DISCUSSION

Although the incidence of colonic diverticular perforation in kidney transplanted patients is similar to that observed in the general population, perforation in immunosuppressed patients is associated with a higher morbidity/mortality rate. In our study, the incidence of perforation is 1.25% (9 of 717), with almost half of the cases observed in patients with ADPKD (4 of 9). Such an observation is consistent with published data, in which patients with ADPKD are reported to more frequently develop colonic diverticulosis and its complications. One possible explanation might be related to a belated diagnosis of diverticulitis, which could initially simulate an inflammatory disease as a consequence of renal cysts. Also, steroids seem to be a predisposing factor for colonic perforation in these patients.

CONCLUSIONS

A timely surgery can significantly reduce mortality. In cases of elective surgery, mortality and morbidity are similar to those of immunocompetent patients; accordingly, this is the goal to be pursued. Early signs and symptoms are often masked by immunosuppressive therapy. In these patients, surgeons should always perform (1) abdominal computed tomography scanning and, in the presence of diverticulitis, reduce or withdraw immunosuppressive therapy; and (2) early surgery, with Hartmann's procedure being, in our opinion, the best choice. Before transplantation, elective surgery for colonic resection should be considered in patients with ADPKD or with a history of 1 or more episodes of acute diverticulitis who then regressed with medical therapy.

Oscillatory mTOR inhibition and Treg increase in kidney transplantation

Intracellular metabolic pathways dependent upon the mammalian target of rapamycin (mTOR) play a key role in immune-tolerance control. In this study, we focused on long-term mTOR-dependent immune-modulating effects in kidney transplant recipients undergoing conversion from calcineurin inhibitors (CNI) to mTOR inhibitors (everolimus) in a 1-year follow-up. The conversion to everolimus is associated with a decrease of neutrophils and of CD8(+) T cells. In addition, we observed a reduced production of interferon (IFN)-γ by CD8(+) T cells and of interleukin (IL)-17 by CD4(+) T lymphocytes. An increase in CD4(+) CD25(+) forkhead box protein 3 (FoxP3)(+) [regulatory T cell [(Treg)] numbers was also seen. Treg increase correlated with a higher proliferation rate of this regulatory subpopulation when compared with the CD4(+) FoxP3(-) effector counterpart. Basal phosphorylation level of S6 kinase, a major mTOR-dependent molecular target, was substantially maintained in patients treated with everolimus. Moreover, oscillations in serum concentration of everolimus were associated with changes in basal and activation-dependent S6 kinase phosphorylation of CD4(+) and CD8(+) T cells. Indeed, T cell receptor (TCR) triggering was observed to induce significantly higher S6 kinase phosphorylation in the presence of lower everolimus serum concentrations. These results unveil the complex mTOR-dependent immune-metabolic network leading to long-term immune-modulation and might have relevance for novel therapeutic settings in kidney transplants.

Forecasting wind power production from a wind farm using the RAMS model

Abstract. The importance of wind power forecast is commonly recognized because it represents a useful tool for grid integration and facilitates the energy trading. This work considers an example of power forecast for a wind farm in the Apennines in Central Italy. The orography around the site is complex and the horizontal resolution of the wind forecast has an important role. To explore this point we compared the performance of two 48 h wind power forecasts using the winds predicted by the Regional Atmospheric Modeling System (RAMS) for the year 2011. The two forecasts differ only for the horizontal resolution of the RAMS model, which is 3 km (R3) and 12 km (R12), respectively. Both forecasts use the 12 UTC analysis/forecast cycle issued by the European Centre for Medium range Weather Forecast (ECMWF) as initial and boundary conditions. As an additional comparison, the results of R3 and R12 are compared with those of the ECMWF Integrated Forecasting System (IFS), whose horizontal resolution over Central Italy is about 25 km at the time considered in this paper. v Because wind observations were not available for the site, the power curve for the whole wind farm was derived from the ECMWF wind operational analyses available at 00:00, 06:00, 12:00 and 18:00 UTC for the years 2010 and 2011. Also, for R3 and R12, the RAMS model was used to refine the horizontal resolution of the ECMWF analyses by a two-years hindcast at 3 and 12 km horizontal resolution, respectively. The R3 reduces the RMSE of the predicted wind power of the whole 2011 by 5% compared to R12, showing an impact of the meteorological model horizontal resolution in forecasting the wind power for the specific site.

Efficacy of subcutaneous epoetin-zeta on anemia in renal transplant recipients: a single-center experience

BACKGROUND

Persistent or "de novo" anemia (plasma hemoglobin<11 g/dL) may complicate the graft outcome in a significant number of renal transplant recipients. We describe a single-center experience with epoetin-zeta (EPO-Z), the biosimilar form for epoetin-alfa.

METHODS

Twenty patients were included in the study, 10 in treatment with different erythropoiesis-stimulating agents (ESA) and shifted to EPO-Z (shift group) and 10 who started EPO-Z treatment for anemia (naive group). All the patients had stable renal function and normal values of main inflammation markers and were prospectively followed up for 12 months. Iron supplements were administered during the study, as needed.

RESULTS

In the shift group, mean plasma hemoglobin levels>11 g/dL were maintained for the entire 1-year follow-up period, with average EPO-Z doses 3.4% higher than the corresponding doses of previous ESA; in the naive group, the target value was reached between the first and third months and remained stable throughout the study. Mean corpuscular volume did not vary in either group. No change was observed in glomerular filtration rate, nor in proteinuria or in main laboratory data. No drug-related side effect was reported.

CONCLUSIONS

EPO-Z may be considered a valid alternative to different ESAs in renal transplant recipients, with an interesting pharmaco-economic profile, considering its lower cost.

Surface high-resolution temperature forecast in southern Italy

Abstract. Since June 2008, 1-h temperature forecasts for the Calabria region (Southern Italy) are issued at 2.5 km horizontal resolution at CRATI/ISAC-CNR. Forecasts are available online at http://meteo.crati.it/previsioni.html (every 6-h). This paper shows the forecast performance out to three days for one climatological year (from 1 December 2008 to 30 November 2009, 365 run) for minimum, mean and maximum temperature. The forecast is evaluated against gridded analyses at the same horizontal resolution. Gridded analysis is based on Optimal Interpolation (OI) and uses a de-trending technique for computing the background field. Observations from 87 thermometers are used in the analysis system. In this paper cumulative statistics are shown to quantify forecast errors out to three days.

Long-term assessment of plasma lipids in transplant recipients treated with tacrolimus in relation to fatty liver

Immunosuppression has improved graft and recipient survival in transplantation but is associated with possible adverse effects including cardiovascular diseases. The impact of tacrolimus on the lipidic profile has been debated for several years. Twenty-nine kidney transplant recipients on tacrolimus treatment were monitored for six years, and multiple laboratory parameters investigating the lipid asset, as well as glucose profile, were carried out. Tacrolimus has been responsible for significant changes in plasma lipid concentrations only for the first six months, but not for the remaining time of observation. Similarly, in the same periods, glycemic imbalance was highlighted. The liver enzyme activity showed a modest derangement during the tacrolimus treatment, suggesting the presence of lipid accumulation in the liver. Fatty liver reversed in the long term follow-up. Tacrolimus, although it is not a completely safe option in the first months of the immunosuppressive protocols in organ transplanted recipients, still retains a certain role in the long-term post-transplantation immunosuppressive approach with high cardiovascular risks.

The seasonal characteristics of the breeze circulation at a coastal Mediterranean site in South Italy

Abstract. We present a study on the characteristics of the sea breeze flow at a coastal site located in the centre of the Mediterranean basin at the southern tip of Italy. This study is finalized to add new data on breeze circulations over a narrow peninsula and present a unique experimental coastal site at about 600 m from the coastline in a flat open area at the foot of a mountain chain located in a region of complex orography. We study the seasonal behaviour of the sea-land breeze circulation by analysing two years of hourly data of wind speed and direction, temperature, radiation and relative humidity from a surface meteorological station, eighteen-months data from a wind profiler, and two-year data from the ECMWF analysis. Results show that breezes dominate the local circulation and play a major role for the local climate. They are modulated by the season, through the sea-land temperature difference and the large-scale flow. The large-scale forcing acts in phase with the diurnal breeze and opposes the nocturnal breeze. In summer, the daytime difference between the land surface temperature and the SST (Sea Surface Temperature) reaches its maximum, while the nigh-time difference has its minimum. This causes a strong, frequent and intense diurnal breeze and a weak nocturnal breeze. In winter and fall the nocturnal difference between the sea and land surface temperature reaches a maximum value, while the diurnal difference is at its minimum value. This causes a strong, frequent and intense nocturnal breeze despite of the large-scale forcing that is usually opposed to local-scale flow.

Effects of voriconazole on tacrolimus metabolism in a kidney transplant recipient

Infection occurs frequently in the organ transplant recipients during the post-transplant period because of immunosuppression. Therefore, prophylactic antimicrobial agents are often used. The azole antifungals, widely prescribed prophylactically, are known to have many drug-drug interactions. This report presents a case of drug-drug interaction between voriconazole and tacrolimus in a kidney transplant recipient. Voriconazole treatment led to a dramatic increase in tacrolimus concentration that required its discontinuation in spite of the manufacturer's guidelines that recommend a reduction of tacrolimus dosage by one-third. The present drug-drug interaction can be attributed to a strong inhibitory effect on cytochrome P450-3A4 activity by voriconazole. When voriconazole and tacrolimus are coadministered, close monitoring of tacrolimus blood levels is recommended as the rule-of-thumb reduction of tacrolimus dose by one-third may not be satisfactory.

Correlation between large-scale atmospheric fields and the olive pollen season in Central Italy

Olives are one of the largest crops in the Mediterranean and in central and southern Italy. This work investigates the correlation of the Olea europaea L. pollen season in Perugia, the capital city of the region of Umbria in central Italy, with atmospheric parameters. The aim of the study is twofold. First, we study the correlation between the pollen season and the surface air temperature of the spring and late spring in Perugia. Second, the correlation between the pollen season and large-scale atmospheric patterns is investigated. The average surface temperature in the spring and late spring has a clear impact on the pollen season in Perugia. Years with higher average temperatures have an earlier onset of the pollen season. In particular, a 1 degrees C higher (lower) average surface temperature corresponds to an earlier (later) start of the pollen season of about 1 week. The correlation between the pollen season and large-scale atmospheric patterns of sea level pressure and 500-hPa geopotential height shows that the cyclonic activity in the Mediterranean is unequivocally tied to the pollen season in Perugia. A larger than average cyclonic activity in the Mediterranean Basin corresponds to a later than average pollen season. Larger than average cyclonic activity in Northern Europe and Siberia corresponds to an earlier than average pollen season. A possible explanation of this correlation, that needs further investigation to be proven, is given. These results can have a practical application by using the seasonal forecast of atmospheric general circulation models.

Quantification of sirolimus and everolimus by immunoassay techniques: test specificity and cross-reactivity evaluation

The possible cross-reactivity of immunoassays with structurally-related drugs was investigated. Innofluor Certican (FPIA) calibrators were measured by using IMx Sirolimus assay (MEIA) and MEIA Sirolimus calibrators were analysed by using FPIA Certican assay. Drug concentrations were measured in 95 and 100 samples from renal transplanted patients (RTP) on sirolimus or everolimus treatment by using immunoassays and LC/ESI-MSMS. A high cross-reactivity was found both for MEIA and FPIA. High correlation degrees, confirmed by the Bland-Altman and the Eksborg tests, were found between drug concentrations measured in real samples by both immunoassays (r = 0.909 and r = 0.970, respectively). LC/ESI-MSMS analysis of samples containing sirolimus showed no positivity for everolimus. Similarly, samples from patients on treatment with everolimus resulted negative as far as regards sirolimus. MEIA and FPIA could be considered mutually reliable and accurate alternatives for the specific-drug immunoassay. It should be noticed that in patients switching from one drug to the other unreal overestimation of the blood levels of the current administered immunosuppressant can occur.

Stability of sirolimus and everolimus measured by immunoassay techniques in whole blood samples from kidney transplant patients

The measurement of blood concentration of immunosuppressive drugs is strongly recommended because of the narrow therapeutic range. An important aspect in the therapeutic monitoring of a drug is its possible degradation. This paper is aimed at investigating the stability of two widely-used immunosuppressants, sirolimus and everolimus. Short (storage at 30 degrees C for 3 or 7 days) and long term (storage at -20 degrees C for 0-90 days with a single freeze-thaw cycle) stability of sirolimus and everolimus in whole blood samples from kidney transplant patients were examined by using MEIA and FPIA. Sirolimus and everolimus samples stored at 30 degrees C in light for up to a week showed a decrement in concentration of 5.2 percent and 6.1 percent, respectively. Our findings on long term stability for both sirolimus and everolimus highlight the possibility of storing samples at -20 degrees C for up to 90 days, without the need to use lower storage temperatures. The results have important implications for patients living far from laboratories where drug concentration is measured or when the storing of blood samples is needed for pharmacokinetic studies.

Older kidneys donor transplantation: five years' experience without biopsy and using clinical laboratory and macroscopic anatomy evaluation

INTRODUCTION

The exponential increase in organ demand is not associated with a similar increase of available kidneys. This emergency led to expanded criteria to consider a kidney transplantable. The aim of this retrospective study was to explain our use of older donor kidneys without biopsy.

MATERIALS AND METHODS

Between 2000 and 2005, 58 older kidneys were harvested: 27 were transplanted in our center; 13 were discarded; and 18 were transplanted in other centers. We considered 3 factors to define kidney quality: macroscopic anatomy, multiple factors linked to the donor, and clinical-laboratory data. After transplantation, we observed the patients for at least 1 year and up to 6 years.

DISCUSSION

At 1 year, 24/27 (89%) patients had a functional kidney, 2 patients showed an initial renal failure and 1 patient lost the kidney. At maximum follow-up, 19 patients (70%) had functional kidneys, 4 with initial renal failure. These results compared with the kidneys harvested using Standard Donor Kidney Criteria are acceptable. Obviously we need long-term follow-up to increase, the amount of data and obtain a definitive outcome.

CONCLUSION

Biopsy is the gold standard for the definition of an older kidney's quality. When a biopsy is not feasible, the study of the macroscopic anatomy the kidney's donor and of some donor's parameters represent an acceptable biopsy alternative, being able to rescue some organs that would be otherwise lost.

Thyroid function and morphology after a successful kidney transplantation

Although thyroid disorders related to the end-stage renal disease (ESRD) are well known, there are discordant data on the function and morphology of the thyroid gland after renal transplantation (RT). The objective of this cross-sectional, case-control study was to investigate the prevalence and risk factors for disorders in the thyroid function and morphology after a successful RT. Fifty consecutive patients (25 females, 25 males) with fully functioning allograft were enrolled. Their age at transplant ranged from 23 to 44 yr (median, 38) and their post-RT follow-up lasted 15-86 months (median, 23). One hundred healthy subjects matched for sex, age and body mass index (BMI) were included as controls. Serum free thyroid hormones, TSH, thyroglobulin, thyroid hormone-binding globulin (TBG) and iodine urinary excretion were determined; ultrasonographic exam of the thyroid gland was performed in all subjects. Age, gender, time elapsed from RT, dialysis duration, kidney function, type of immunosuppression and corticosteroid dose were considered as possible influencing factors for the thyroid function. Hypothyroidism was found in 6% of patients, "low T3 syndrome" in 52%, while another 26% had free T3 (FT3), free T4 (FT4) and TSH in the lowest third of the normal range, suggesting inhibition of the whole hypothalamic-pituitary-thyroid (HPT) axis. Iodine excretion and prevalence of anti-thyroid antibodies were similar in both patients and controls. There was no significant difference in the thyroid function according to different immunosuppressive regimens. In patients, an ultrasonographic exam revealed a very variable thyroid volume ranging from 7.2 to 24.8 ml. Solid nodules were detected in 12 (24%) cases and cystic lesions in another four (8%); they were proven negative at cytological examination. Dialysis duration was longer in patients with thyroid nodules than in those without (p<0.05). Inhomogeneous hypoechoic pattern typical for chronic thyroiditis was more frequent than its biochemical expression. In conclusion, a high prevalence of abnormal thyroid morphology was found in patients after a successful RT, being partly related to a previous uremia. Abnormalities in the thyroid function are likely an expression of the post-transplant general and immunological conditions. Endocrinological follow-up is advisable in patients after RT, in order to discriminate thyroid dysfunctions which need specific treatments from those that can only be followed-up, avoiding inappropriate treatments of biochemical abnormalities.

Considerations on Joint and Articular Cartilage Mechanics

When studying joint degeneration leading to osteoarthritis (OA), it seems imperative that local joint tissue loading is known during normal everyday movement and that the adaptive/degenerative effects of this loading are quantified systematically. Philosophically, we believe the best way to approach this problem is by studying joint degeneration and osteoarthritis in long-term experimental models and by representing diarthrodial joints and the associated tissues with accurate, geometric and structural, theoretical models. Here, we present selected examples of our work representing this approach. Experimentally, we demonstrate that the local loading of joints changes continuously in experimental models of OA, not only because of the changing external and internal loading, but also because of the continuous alterations in joint contact geometry and tissue mechanical properties. Furthermore, we show that single bouts of joint loading affect gene expression, and that gene expression, as well as subsequent joint degeneration is site-specific. In fact, opposing articular surfaces that are exposed to the same loading may degenerate at completely different rates. Finally, we propose a series of theoretical models of articular cartilage and contact mechanics, demonstrating that many of the anisotropic and inhomogeneous properties can be explained by structural elements and their orientation and volumetric concentration across the tissue.

The Mechanical Behaviour of Chondrocytes Predicted with a Micro-structural Model of Articular Cartilage

The integrity of articular cartilage depends on the proper functioning and mechanical stimulation of chondrocytes, the cells that synthesize extracellular matrix and maintain tissue health. The biosynthetic activity of chondrocytes is influenced by genetic factors, environmental influences, extracellular matrix composition, and mechanical factors. The mechanical environment of chondrocytes is believed to be an important determinant for joint health, and chondrocyte deformation in response to mechanical loading is speculated to be an important regulator of metabolic activity. In previous studies of chondrocyte deformation, articular cartilage was described as a biphasic material consisting of a homogeneous, isotropic, linearly elastic solid phase, and an inviscid fluid phase. However, articular cartilage is known to be anisotropic and inhomogeneous across its depth. Therefore, isotropic and homogeneous models cannot make appropriate predictions for tissue and cell stresses and strains. Here, we modelled articular cartilage as a transversely isotropic, inhomogeneous (TI) material in which the anisotropy and inhomogeneity arose naturally from the microstructure of the depth-dependent collagen fibril orientation and volumetric fraction, as well as the chondrocyte shape and volumetric fraction. The purpose of this study was to analyse the deformation behaviour of chondrocytes using the TI model of articular cartilage. In order to evaluate our model against experimental results, we simulated indentation and unconfined compression tests for nominal compressions of 15%. Chondrocyte deformations were analysed as a function of location within the tissue. The TI model predicted a non-uniform behaviour across tissue depth: in indentation testing, cell height decreased by 43% in the superficial zone and between 11 and 29% in the deep zone. In unconfined compression testing, cell height decreased by 32% in the superficial zone, 25% in the middle, and 18% in the deep zones. This predicted non-uniformity is in agreement with experimental studies. The novelty of this study is the use of a cartilage material model accounting for the intrinsic inhomogeneity and anisotropy of cartilage caused by its microstructure.

Blood Cyclosporine Level Soon After Kidney Transplantation is a Major Determinant of Rejection: Insights From the Mycophenolate Steroid-Sparing Trial

Target organs express antigens directly recognized by antigen-specific T cells, thereby precipitating rejection. When early T-cell activation is inhibited, there is a low risk of rejection. We sought to determine the predictive values of serial posttransplant blood cyclosporine trough (C(0)) concentrations to minimize the risk for a first rejection episode compared with 2-hour postdose (C(2)) drug concentrations. The final aim of the study was to identify a concentration range for the best predictive pharmacokinetic parameter that should be targeted to reduce the risk of rejection. This possibility was explored in 334 de novo kidney transplant recipients who participated in the prospective, multicenter Mycophenolate Steroid-Sparing Trial. Among measurements performed during the first 6 months postsurgery, cyclosporine C(0) levels measured early after transplantation were the strongest predictor of acute graft rejection. Levels within 300 to 440 ng/mL were associated with the lowest risk of rejection, while patients with levels lower than 300 ng/mL showed a more than double risk. Cyclosporine trough values predicted allograft rejection with an accuracy of 74%, while C(2) levels had no predictive value. These findings underline the need to target cyclosporine therapy early posttransplant to modulate T-cell activation.

A Randomized Trial of Steroid Avoidance in Renal Transplant Patients Treated with Everolimus and Cyclosporine

In this randomized trial renal transplant recipients were treated with basiliximab, everolimus 3 mg/day, low-dose CsA. At transplantation, patients were randomized to stop steroids at the seventh day (group A) or to continue oral steroids in low doses (group B). Of the 113 patients enrolled, 65 were randomized to group A and 68 to group B. All patients were followed for 2 years. During the study 28 (43%) group A patients required reintroduced corticosteroids. One patient died, in group B. The Graft survival rate was 97% in group A and 90% in group B. There were more biopsy-proven rejections in group A (32% vs 16%; P = .044). The mean creatinine clearance was 54 +/- 21 mL/min in group A vs 56 +/- 22 mL/min in group B. Mean levels of serum cholesterol tended to be lower in group A, but the difference was of borderline significance (191 +/- 91 vs 251 +/- 188 mg/dL; P = .07). Vascular thrombosis (0 vs 5) and pneumonia requiring hospitalization (2 vs 7) tended to be more frequent in group B. Only three cases of CMV infection (1 vs 2) occurred. An immunosuppressive therapy with everolimus and low-dose CsA allows one to obtain excellent renal graft survival and stable graft function at 2 years. Early interruption of steroids in patients treated with this regimen may increase the risk of acute rejection, but neither affects graft survival nor graft function, while possibly reducing the risk of hyperlipemia and vascular thrombosis. About 60% of patients given everolimus and low-dose CsA can definitively stop steroids after 1 week.

Enzyme replacement therapy with agalsidase beta improves cardiac involvement in Fabry's disease

Fabry's disease is an X-linked lysosomal storage disease caused by a deficiency of alpha-galactosidase that results in an accumulation of neutral glycosphingolipids throughout the body, including the cardiovascular system. Fabry cardiomyopathy, characterized by progressive severe concentric left ventricular (LV) hypertrophy, is very frequent and is the most important cause of death in affected patients. Enzyme replacement therapy (ERT) allows a specific treatment for this disease, however, there are very few data on the effectiveness of therapy on cardiac involvement. Nine patients with Fabry cardiac disease were studied on basal condition and after 6 and 12 months of treatment with algasidase beta (Fabrazyme). A complete clinical, electrocardiographic and echocardiographic evaluation was performed in all patients. Interpretable Doppler recordings of transmitral flow and pulmonary flow velocity curves were also acquired. At baseline, the patients with Fabry's disease had increased LV septum and posterior wall thickness, normal LV fractional shortening, LV ejection fraction, normal Doppler parameters of mitral inflow but a duration of pulmonary vein flow velocity wave exceeding that of the mitral wave at atrial systole. ERT did not affect heart rate and arterial pressure. LV internal diameters did not change, there was a slight but not significant decrease in the LV posterior wall thickening and a progressive decrease in the interventricular septum thickening (p < 0.025) and in LV mass (p < 0.001) The difference in duration between pulmonary vein flow velocity wave and mitral wave at atrial systole significantly decreased (p < 0.001). These results suggest that ERT in patients with Fabry cardiomyopathy is able to reduce the LV mass and ameliorate the LV stiffness.

Opinions on renal transplantation and organ donation in high school students in two large northern (Torino) and southern (Napoli) Italian cities

Organ shortage for transplantation has focused attention on educational interventions. Italy is a nonhomogenous country whose cultural and economic differences are reflected in the health-care system: dialysis is mainly public in the north versus private in the south; and transplantation rates display a wide range from 3.4 to 37.8 per million people in 2002. The aim of the present study was to analyze the opinions of population of high school students (last two years) in two large cities: northern (Torino) and southern (Napoli) Italy, as a knowledge base for a randomized controlled trial on the efficacy of educational interventions on renal replacement therapy and organ donation, targeted to high school students.

METHODS

This preliminary study included eight public high schools that completed a first and anonymous semistructured questionnaire. Five hundred and eighty nine questionnaires were retrieved in Torino and 539 in Napoli. In both cities most students answered that they would give a kidney to a brother, sister, or partner needing dialysis (Torino: yes 80.6%; no 2.2%, uncertain-blank 17.2%; Napoli: yes 86.1%, no 1.1%; uncertain-blank 12.8%). Only 36.3% of the students in Torino and 37.7% in Napoli answered that they would consent to organ donation, if they had to choose for a strict relative with brain death. Opposition was 28% in Torino and 23.7% in Napoli; 35.7% in Torino and 38.6% in Napoli were blank-uncertain. These data underline the need for detailed information on the opinions of the overall population as basis for tailored educational campaigns.

[A clinical case of a giant lymphocele (LC) in a patient with a recent renal transplant is described]

BACKGROUND

The lymphocele (LC) described was associated with a sharp increase in plasma creatinine values, in the absence of any clinical symptoms. A open laparotomy procedure determined the resolution of the LC and the slow recovery of renal function. The huge dimensions of the LC (volume >3000 cc) and its pelvic localization, which dislocated both the bladder and the transplanted kidney, make this case unique, since the LC mimicked a particularly dilated bladder.

CONCLUSIONS

We discuss how therapies, rejection episodes, follow-up modalities, and surgical procedures may influence the onset of this frequent complication of renal transplantation.

[Anderson-Fabry's disease: diagnostic problems, therapeutic relevance, and clinical experience in the treatment of the disease with enzyme replacement therapy in nephropathic patients]

Aim of this study was to confirm the initial results of a clinical trial on the treatment of Fabry's disease carried out in 13 Italian Nephrology Units. Fabry's disease is a rare, X-linked inherited disease, characterized by a-galactosidase (a-GAL) deficiency, a lysosomial enzymatic activity that results in the accumulation of neutral glycosphingolipids in the endothelial cells of the whole body, and causes painful crises, acroparesthesiae, angiokeratomas, corneal and lens dystrophy, and progressive damage to kidneys, heart and central nervous system, as well as potentially leading to death. The present availability of the recombinant form of a-GAL allows us to prevent or stop the long-term complications of this disease. A clinical trial, generously supported by Genzyme, was started on February 2001. In this trial 20 patients affected by Fabry's disease were periodically treated with agalsidase-beta, the commercial form of the enzyme. The initial results of the trial have indicated that the drug is capable of reducing both the number and intensity of painful crises, improving the patient's sensation of well-being, thus suggesting that this therapeutic approach might theoretically increase life expectancy in these patients.

Edema and acute renal failure

Acute renal failure (ARF) with overhydration and edematous state may follow Acute endocapillary proliferative glomerulonephritis and extracapillary glomerulonephritis, because of reduction of the glomerular capillary area available for filtration. But ARF may also be observed in edematous patients with minimal change nephrotic syndrome; it may require dialysis until recovery and is attributable to some of the following factors: (1) ischemic renal injury, (2) hypovolemia, (3) interstitial edema with tubular collapse, (4) redistribution of renal blood flow (RBF) from cortical to juxtaglomerular nephrons, (5) decrease of capillary filtration coefficient (Kf), (6) use of nonsteroidal antiinflammatory drugs. Congestive heart failure also leads to prerenal azotemia and edema formation secondary to salt retention. Multiple organ dysfunction syndrome (MODS) is frequently associated with ARF; but edema occurs even without ARF in septic patients with severe inflammatory response syndrome (SIRS). ARF may follow severe burns; burned patients are frequently edematous because of a rapid leak of fluid from the vascular bed into the wound; edema in undamaged areas occurs in the 'flow phase', because of a fall of oncotic pressure because of massive loss of plasma proteins into the wound. Edema must be treated with diuretics or by dialysis.

A randomized study comparing three cyclosporine-based regimens in cadaveric renal transplantation. Italian Multicentre Study Group for Renal Transplantation (SIMTRe)

Whether it is better to treat renal transplant patients with cyclosporine alone, combined with steroids, or combined with steroids and azathioprine is still unclear. After initial therapy with cyclosporine and steroids, 354 cadaver renal transplant recipients were randomly assigned at the post-transplant day 5 to cyclosporine alone (monotherapy), cyclosporine plus steroids (double therapy), or cyclosporine plus steroids plus azathioprine (triple therapy). Monotherapy patients, after a second acute rejection, were switched to either of the two alternative therapies. According to intention-to-treat (ITT) analysis, the 4-year patient survival was 97% in monotherapy, 91% in double therapy, and 96% in triple therapy; the graft survival including death was 84%, 77%, and 88%, respectively; and the pure graft survival was 87%, 85% and 91%, respectively (P = not significant). Acute rejections were diagnosed in 79 patients in monotherapy, 58 in double therapy, and 59 in triple therapy (P < 0.01). Of the patients on monotherapy, 52% were switched to double or triple therapy. In these patients, the 4-year graft survival including death was 68%, and the pure graft survival was 72%, in comparison with 93% and 94%, respectively, for patients who continued on cyclosporine alone. Patients with renal polycystic disease as a cause of renal failure and with low plasma creatinine at the time of randomization (5 days after transplant) had a higher probability of remaining on monotherapy, wherease those with glomerulonephritis or systemic lupus erythematosus (SLE) and with high plasma creatinine levels at randomization had a higher probability of being switched to double or triple therapy. According to ITT analysis, there were fewer ocular (P < 0.0001), osteomuscular (P < 0.002) and cardiovascular complications (P = 0.05) and fewer patients with hypercholesterolemia (P < 0.0028) in the monotherapy group, with no difference between double and triple therapy. Creatinine clearance at 3 years was lower in monotherapy, but no attrition of renal function was seen over the years in any of the groups. Cyclosporine, however used, provided good results in cadaveric renal transplantation. Triple therapy and monotherapy offered a nonsignificantly better patient and graft survival than double therapy. Patients on monotherapy had a higher risk of acute rejection but had fewer adverse events than those on double or triple therapy. Patients maintained on cyclosporine alone had the best graft survival, whereas those who were assigned to monotherapy and had to add steroids because of multiple rejections had the worst outcome. Therefore, it seems reasonable to limit the choice of monotherapy to patients without immune-mediated renal diseases and with good graft function in the early post-transplant period.

Changes in middle cerebral artery blood velocity in uremic patients after hemodialysis

BACKGROUND AND PURPOSE

Strokes are a frequent complication in uremic patients on dialysis. We wanted to evaluate the effect of this treatment on cerebral hemodynamic parameters, particularly those of patients with carotid stenosis, who are at higher risk for atherothrombotic ischemic events.

METHODS

We used transcranial Doppler ultrasonography to evaluate blood velocity of the middle cerebral artery in 18 uremic patients before and after hemodialysis. Carotid stenosis was evaluated by echo-Doppler investigation. Six patients were also studied before and after recombinant human erythropoietin treatment.

RESULTS

Dialysis treatment decreased mean blood velocity in all patients (p less than 0.001). Eight of 18 patients (44%) with mild (16-50%), moderate (51-80%), or severe (greater than 80%) carotid stenosis had lower velocity than patients with normal carotid arteries (p less than 0.01), and they experienced a further decrease to even lower levels after hemodialysis (p less than 0.05). In patients treated with recombinant human erythropoietin, hematocrit increased from 28 +/- 8% to 37 +/- 5% (p less than 0.001), and blood velocity had a further decrease by 11%. All changes were associated with modifications toward normality of pH, PaCO2, and hematocrit.

CONCLUSIONS

Transcranial Doppler ultrasonography represents a useful method for monitoring cerebral circulation of uremic patients, especially of those at possible risk for ischemia.

Effects of furosemide therapy on free-water excretion in uremic patients

To assess the intrinsic effects of treatment with furosemide on free-water excretion in patients with chronic renal failure, two groups of patients with and without replacement of diuretic-induced salt losses have been studied. Furosemide therapy was administered for 1 week during constant sodium intake (100 mEq/day). In neither of the groups did furosemide cause hyponatremia, while it did decrease the urine to plasma osmolality ratio, an effect lasting even when the diuretic effect was exhausted. During water diuresis, furosemide decreased the fractional sodium reabsorption in diluting segments but not the absolute rate of the free-water generation (CH2O). Presumably the expected decrease of CH2O was masked by the increased distal delivery of tubular fluid mainly due to an additional effect of the diuretic on the proximal tubule. The hypotonicity of urine after furosemide treatment may be secondary to the dissipation of medullary hypertonicity, caused by furosemide, in the condition of decreased water permeability of the collecting duct due to uremic disease.

Angiotensin II inhibition with captopril on plasma ADH, PG synthesis, and renal function in humans

Using captopril (C), an angiotensin (ANG) I converting-enzyme inhibitor, to increase endogenous prostaglandins (PGs) and to decrease endogenous ANG II synthesis, we studied the relationship between endogenous ANG II, PG, and antidiuretic hormone (ADH) release in seven normal volunteers before (control study) and after inhibition of PG synthesis by a single dose of aspirin (ASA study). In the control study, following the administration of 100 mg of C, there was a significant increase of plasma PGE2, plasma-renin activity (PRA), and urinary PGE2 and 6-keto-PGF1 alpha and a decrease of plasma ADH. Glomerular filtration rate (GFR) and renal plasma flow (RPF) were unaffected by C; urine output, fractional sodium excretion (FENa), and osmolal clearance (Cosmol) increased; and urinary osmolality (Uosmol) decreased significantly after C. In the ASA study PG were undetectable in plasma and significantly reduced in urine 1 h after aspirin and did not increase when C was added. Plasma ADH decreased and PRA increased, as in the control study, after C, whereas GFR, RPF, urine output, FENa, Cosmol, and Uosmol were unchanged. These results suggest that the effect of C on ADH release may be mediated, to a large extent, by a fall in endogenous circulating ANG II, since ADH decreased in the presence of both high or undetectable levels of PGE2. The results also suggest that the increase in PGE2 induced by C may precipitate the diuretic and natriuretic effects of acute C administration.

Mechanism of action of indomethacin in tubular defects

Indomethacin, a potent prostaglandin synthesis inhibitor, has been proven to be effective in a number of tubular defects characterized by enhanced prostaglandin (namely, prostaglandin E2 (PGE2) production, but its mechanism of action is poorly understood. To elucidate further the mechanism(s) by which indomethacin reverses the abnormal tubular functions, five children with different tubular defects (nephrogenic diabetes insipidus, three cases; Fanconi syndrome, one case; and pseudohypoaldosteronism, one case) were treated with indomethacin. Indomethacin, 1 mg/kg every eight hours, was given for 1 week to all children and then was given chronically to four of the children who responded to the drug. Its use was suspended in a 10 year-old-boy with nephrogenic diabetes insipidus because it proved ineffective. To assess the site along the nephron where indomethacin affects the solute and water excretion, an acute water load study was performed in three responsive children before and during the treatment. Indomethacin did not significantly alter the glomerular filtration rate but was effective in reducing diuresis and levels of urinary sodium and potassium excretion. In the child with Fanconi syndrome, indomethacin was also effective in controlling the urinary loss of phosphate, urate, glucose, and bicarbonate. Results of the water load studies show that indomethacin decreases the delivery of solute from the proximal tubule, reduces the fractional free water clearance, and increases the urine-plasma osmolar ratio.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of angiotensin II on plasma ADH, prostaglandin synthesis, and water excretion in normal humans

To verify whether angiotensin II (ANG II) stimulates ADH release in humans and to evaluate whether endogenous prostaglandins influence the resulting renal effect of ADH, nonpressor and low pressor doses of ANG II were infused in nine normal volunteers under normal conditions (control study) and after prostaglandin synthesis inhibition with aspirin (ASA study). During ANG II infusion plasma ADH increased in both conditions. Plasma PGE2, urinary PGE2, and urinary 6-keto-PGF1 alpha increased only in the control study, whereas they were undetectable in the plasma and significantly reduced in the urine in the ASA study. ANG II caused a significant fall of glomerular filtration rate, renal plasma flow (with an increase in filtration fraction), fractional sodium excretion, and urine output in both studies. Despite the reduced urine output, urine osmolality decreased significantly in the control study, whereas it increased after aspirin administration. These results suggest that intravenous ANG II stimulates ADH release in humans but that the renal effects of the resulting increase in plasma ADH are different depending on the presence or absence of endogenous prostaglandins.

Role of plasma vasopressin in the impairment of water excretion in nephrotic syndrome

To verify whether or not an increased secretion of ADH may cause the water retention commonly observed in nephrotic syndrome, 16 nephrotic patients and 13 normal control subjects were studied in basal conditions and following a water load or an iso-osmotic blood volume expansion by 20% albumin infusion. In the basal condition there were no differences in plasma ADH, urine output, urinary osmolality (UOsm), and plasma renin activity between nephrotic patients and control subjects; POsm, PNa+, UNaV, and blood volume (BV) instead, were significantly lower in nephrotic patients than in control subjects. Following the water load control subjects reached a minimal UOsm of 82 +/- 12 mOsm/kg at 60 min and excreted completely the ingested water in 150 min; nephrotic patients reached a minimal UOsm of 160 +/- 111 mOsm/kg at 120 min, and the water was eliminated completely in 240 min. Plasma ADH decreased significantly in the first hour following water load only in control subjects. A significant direct correlation was observed between plasma ADH and POsm in control subjects (ADH = -85 + 0.30 POsm, P less than 0.001) but not in nephrotic patients. Plasma ADH was inversely correlated with BV in nephrotic patients (ADH = 15.47 -0.17 BV, P less than 0.001) but not in normal control subjects. In nephrotic patients with reduced BV the expansion of BV with 20% albumin was effective in reducing the plasma levels of ADH and promoting a water diuresis. Our results demonstrate a sustained volume mediated secretion of ADH in the nephrotic syndrome, which is responsible for the impairment in water excretion.

Long-term follow-up of minoxidil therapy in refractory hypertension. A prospective trial in patients with various degrees of renal insufficiency

Thirty patients with various degrees of renal insufficiency (4 on dialysis treatment) and severe hypertension refractory to conventional agents were treated with minoxidil and followed for up to 182 weeks. BP averaging 203 +/- 8.8/125 +/- 4.1 mm Hg supine and 194 +/- 7.8/125 +/- 3.9 upright before treatment, fell to 155 +/- 6.2/92 +/- 3.4 and 146 +/- 6.3/92 +/- 3.2 respectively within 1 week with 5 to 30 mg daily of minoxidil and remained stabilized around these normal values for three years or more. However, increasing doses of the drug became necessary after 52 weeks of therapy. Serum creatinine increased slightly during long-term treatment in most patients suggesting that the fall in renal function with time should be attributed to the natural progression of normotensive chronic renal failure. Adequate dialysis (in the 4 dialyzed patients) and high-ceiling diuretics prevented fluid imbalance during minoxidil therapy, while beta-blocking agents allowed complete control of reflex tachycardia.

[Treatment of arterial hypertension with minoxidil in renal insufficiency]

Minoxidil was administered to 13 patients with arterial hypertension resistant to ordinary antihypertensive drugs and with various degrees of renal failure. Four patients were followed in this way for 50 weeks. Blood pressure values fell from 208 +/- 9.8/124 +/- 4.8 to 153.1 +/- 7.8/86.9 +/- 2.6 at the end of the treatment period. Propanolol and furosemide were used to offset sodium retention and reflex tachycardia. There was no decrease in renal function. In patients examined for the longest period, the minoxidyl dose, after an intermediate reduction stage, reached the 8th week value. Hypertrichosis was the most disturbing side-effect, especially for the female patients. The question of pericarditis is discussed.

Relationship between serum albumin concentration and tubular reabsorption of glucose in renal disease

Micropuncture studies in rats and dogs have provided evidence for a cause-and-effect relationship between peritubular protein concentration and proximal tubular reabsorption (PTR). If this effect is obtained in man, hypoalbuminemia in nephrotic syndrome should lead to a fall in PTR. Sodium excretion, however, is very low in nephrotic patients; but this sodium retention may be due to distal over-reabsorption. Glucose may be used as a marker of PTR. Because of the linkage between glucose and sodium, glucose reabsorption is expected to be suppressed when PTR of sodium is suppressed. Glucose titration studies were performed in 21 patients with chronic glomerulonephritis without renal failure divided in three groups: I (six patients) with serum albumin greater than 3 g/100 ml; II (five patients) with serum albumin of 2 to 3 g/100 ml; and III (10 patients with edema and nephrotic syndrome) with serum albumin less than 2 g/100 ml. The minimum threshold for glucose decreased in nephrotic patients (group III), and its fall was related directly to hypoalbuminemia. The splay of titration curve was markedly increased in group III when compared to the titration curves of patients without nephrotic syndrome (groups I and II). The splay point was 0.78 in group I, 0.52 in group II, and 0.37 in group III. These data provide evidence that glucose reabsorption is decreased in nephrotic syndrome and are consistent with a fall in PTR in nephrotic syndrome.