Indication to renal biopsy in DM2 patients: potential role of intrarenal resistive index.

Diagnosis of diabetic nephropathy is generally based, rather than on histological confirmation, on clinical criteria (long history of diabetes, presence of proteinuria, diabetic retinopathy or peripheral neuropathy). This clinical approach has perhaps limited utility in DM2 patients, because only 50% of them show microvascular complications in presence of nephropathy. Eco-colour-Doppler sampling of interlobular renal arteries and determination of their resistance indices (RI), was proposed in the differential diagnosis of numerous nephropathies. Aim of this study was to evaluate whether RI can be useful in discerning non-diabetic renal disease (NDRD), in order to better define indications to perform renal biopsy among proteinuric DM2 patients. All patients were submitted to: echo-colour-Doppler study of renal vessels; systematic screening for diabetic retinopathy; needle renal biopsy. RI resulted to be significantly higher in diabetic glomerulosclerosis (GSD) group as compared with NDRD group, while no significant difference was found with respect to NDRDs overlapping GSD (overlapping group). The last one showed however median RI significantly higher than isolated NDRD group. Normalized chi square Pearson for the hypothesis that RI can predict GSD resulted 0.73, while it resulted 0.43 for the hypothesis that diabetic retinopathy can predict GSD. Echo-colour-Doppler can significantly contribute, more than the other parameters proposed (nephritic or nephrotic syndrome, hematuria, diabetic retinopathy), to the identification of underlying nephropathy in DM2 subjects. In the light of our experience, it seems that the detection of RI values > 0.72 suggests the diagnosis of GSD or mixed forms, reducing the indications to renal biopsy only in presence of values < 0.72.

[Use of ECG-EC in the positioning of central venous catheters]. / Elettrocardiografia endocavitaria nel posizionamento dei cateteri venosi centrali.

Central venous catheters (CVC) are widely used in clinical practice for the administration of chemotherapy, parental nutrition, hemodynamic monitoring, and hemodialysis. International guidelines have defined the right internal jugular vein as the preferred site of CVC insertion and underline that accurate positioning of the catheter tip is essential to maximize the blood flow and reduce long-term complications. Endocavitary electrocardiography (EC-ECG) improves the accuracy of catheter tip positioning without increasing the placement time by the recognition of typical P wave patterns during catheter insertion:the normally shaped P wave identifies the mid to upper superior vena cava, the widest P wave may be used to place the CVC tip at the superior vena cava-right atrium junction, and biphasic P waves identify the location of the right atrium. Because of its simplicity and safety, EC-ECG should always be considered during CVC placement, especially if other means of verifying correct CVC insertion are not available.

[The future of the ultrasonography techniques in nephrology]. / Il futuro delle tecniche ultrasonografiche in nefrologia.

Thanks to the wide geographical diffusion, low cost and lack of ionizing radiation, ultrasound is now the most widely used imaging technique in clinical practice, second only to chest radiography. Recent technological innovations and introduction of ultrasound contrast agents, further expanded the fields of application of ultrasound, guarantying for the future to this technique an important role in imaging of the urinary tract. The nephrologist must be able to exploit the potential offered by technological innovations in ultrasound imaging for the study of the kidney. The proper management of equipment, in fact, allows to obtain ultrasound images in gray scale of the highest quality, to optimize the diagnostic accuracy of Doppler techniques and take full advantage of the tools offered by means of ultrasound contrast agents.

[Microbubbles: current state and future prospects]. / Le microbolle: attualita' e prospettive future.

Contrast-enhanced ultrasound (CEUS) represents one of the most interesting applications of traditional medical sonography. Ultrasound contrast agents are classified into first- and second-generation agents depending on the gas (nitrogen, perfluorocarbon or sulfur hexafluoride) in the microbubbles. Both generations are characterized by an excellent safety profile, with low hepatic and renal toxicity and rare central nervous system reactions. The respiratory and hepatic elimination of the gases explains the low nephrotoxicity. CEUS has been successfully employed in drug and gene delivery. Indeed, new molecules such as liposomes, micelles and perfluorocarbon nanoparticles have been recently proposed as ultrasound contrast agents. Possible future applications of liposomes are the treatment of hypertension complications (given the possibility to fill them with nitric oxide), the treatment of cerebral disease with xenon, and the treatment of breast and liver cancer with doxorubicin. Micelles have been demonstrated to be effective in cancer treatment as well. Finally, perfluorocarbon nanoparticles can be used in oncological settings and in pancreatic islet transplantation in patients with type I diabetes.

[Contrast enhanced ultrasound in renal diseases]. / L'imaging ecocontrastografico nella patologia renale.

Contrast-enhanced ultrasound (CEUS) is one of the most interesting and promising clinical applications of imaging and ultrasound. Thanks to the absence of ionizing radiation, the lack of nephrotoxicity and low cost it has the potential to become a reference in imaging of the kidney. This review, besides providing a brief description of the proper methodology, presents possible applications of CEUS in nephrology and urology, including renal ischemia, the differential diagnosis of cystic and solid lesions, follow-up of ablative therapies, kidney trauma, kidney transplant, inflammatory diseases, ischemic nephropathy and vesicoureteral reflux.

[Ultrasound assessment in renal infections]. / L'ecografia nelle infezioni del rene.

Urinary tract infections (UTIs) are a common clinical problem, especially among women. Ultrasound assessment is indicated in case of complicated UTIs, in particular in children, pregnant women and patients with chronic kidney disease. Even though B-mode imaging alone is rarely diagnostic in case of particular kidney infections such as focal and multifocal acute pyelonephritis, Doppler and power-Doppler (PD) techniques are able to increase its sensitivity. Contrast-enhanced ultrasound (CEUS) further improves the signal-to-noise ratio, thus increasing the diagnostic accuracy of ultrasound in case of renal infectious disease. Recent studies performed on kidney transplant recipients have indeed demonstrated the high sensitivity and specificity of CEUS in diagnosing acute pyelonephritis. Moreover, ultrasonography is a useful diagnostic tool in case of kidney abscesses, emphysematous pyelonephritis, early phases of pyonephrosis, and in the evaluation and monitoring of echinococcal cysts. Ultrasound imaging is less specific in diagnosing xanthogranulomatous pyelonephritis, malacoplakia and renal tuberculosis. Finally, several authors recommend routine ultrasound assessment in HIV patients, given the high incidence of renal complications in this population of patients.

[Vascular complications following kidney transplant: the role of color-Doppler imaging]. / Le complicanze vascolari del rene trapiantato: il ruolo dell'eco-color-Doppler.

The progressive decline in the incidence of graft rejection has made urological, surgical, parenchymal and vascular complications of kidney transplant more frequent. The latter, although accounting for only 5-10% of all post-transplant complications, are a frequent cause of graft loss. Ultrasonography, both in B-mode and with Doppler ultrasound, is an important diagnostic tool in case of clinical conditions which might impair kidney function. Even though ultrasonography is considered fundamental in the diagnosis of parenchymal and surgical complications of the transplanted kidney, its role is not fully understood in case of vascular complications of the graft. The specificity of Doppler ultrasound is very important in case of stenosis of the transplanted renal artery, pseudoaneurysms, arteriovenous fistulas, and thrombosis with complete or partial artery or vein occlusion. Doppler and color determinations present high diagnostic accuracy, which is higher in case of successive measurements performed during the follow-up of the graft. Modern techniques including contrast-enhanced ultrasound increase the diagnostic power of ultrasonography in case of vascular complications of the transplanted kidney, planted kidney.

[Echocardiography in nephrology]. / L'ecocardiografia in nefrologia.

Cardiovascular disease is the main cause of mordibity and mortality in patients with chronic kidney disease (CKD) affected by a series of risk factors (hypertension, anemia, left ventricular hypertrophy, cardiac failure and dyslipidemia). The combined presence of these factors raises the cardiovascular risk in CKD patients considerably compared with that of the general population. Nephrologists can play a role in preventing and treating these risk factors and thereby delaying the development of CKD. In preventing CKD, nephrologists who practice ultrasound techniques should have basic know how of echocardiography so that they can screen CKD patients for early referral to a cardiologist. Echocardiography is a noninvasive ultrasound technique that requires adequately trained doctors to perform it. Nephrologists who practice it need to obtain good training and postgraduate certification of competence in echocardiography. These nephrologists should team up with cardiologists rather than replace them, and at the same time be aware that they possess the basic knowledge to manage cardiovascular disease in CKD patients.

[Management of color-Doppler imaging in dialysis patients]. / Il nefrologo e la gestione ecocolorDoppler del paziente in dialisi.

In recent decades, the survival of dialysis patients has gradually increased thanks to the evolution of dialysis techniques and the availability of new drug therapies. These elements have led to an increased incidence of a series of dialysis-related diseases that might compromise the role of dialysis rehabilitation: vascular disease, skeletal muscle disease, infectious disease, cystic kidney disease and cancer. The nephrologist is therefore in charge of a patient group with complex characteristics including the presence of indwelling vascular and/or peritoneal catheters, conditions secondary to chronic renal failure (hyperparathyroidism, anemia, amyloid disease, etc.) and superimposed disorders due to old age (cardiac and respiratory failure, cancer, type 2 diabetes mellitus, etc.). Early clinical and organizational management of such patients is essential in a modern and ''economic'' vision of nephrology. The direct provision of ultrasound services by the nephrologist responds to these requirements. A minimum level of expertise in diagnostic ultrasonography of the urinary tract and dialysis access should be part of the nephrologist's cultural heritage, acquired through theoretical and practical training programs validated by scientific societies, especially for those who choose to specialize in these procedures and become experts in imaging or interventional ultrasonography.

[The nephrologist and the role of ultrasound imaging in the diagnosis of cardiorenal syndrome]. / Il nefrologo e il ruolo dell'imaging ultrasonografico nella diagnosi di sindrome cardio-renale.

The term cardiorenal syndrome (CRS) refers to multiple possible clinicopathological correlations between heart and kidney failure. The most recent classification recognizes five types of CRS: types I and II originate from heart failure (acute and chronic, respectively), type III and IV from kidney failure (again acute and chronic), while type V originates from a range of systemic diseases. Echocardiography and renal ultrasound are important means to arrive at a correct diagnosis. Basic echocardiography (defined by some as "echocardioscopy") allows the assessment of the left and right ventricles (diastolic and systolic function), atrial size, pulmonary circulation markers such as systolic pulmonary arterial pressure (PAPs) and tricuspid annular plane excursion (TAPSE), pericardial effusions, valve dysfunctions, and volume repletion. Renal ultrasound is of help in distinguishing between chronic and acute renal failure (kidney volume, parenchymal thickness, echogenicity) and excluding obstructive kidney disease.

Hemodynamic impact of VASQ device in vascular access creation.

BACKGROUND: Native arteriovenous fistula is the preferred vascular access in term of functionality, efficiency and complication rate. Nevertheless, research continues to seek strategies to reduce the risk of neointimal hyperplasia and hemodynamic modification. The aim of the study was to evaluate the impact on hemodynamic of the VasQ device in arteriovenous fistulae creation. METHODS: The analysis included patients who underwent to fistula creation with or without implantation of the VasQ device between May and September 2019. The hemodynamic parameters were evaluated pre-operatively and at a follow-up of 1, 3, 6 months. The patency and complication rate were evaluated. RESULTS: Fifteen VasQ devices were implanted during 30 arteriovenous fistula surgery. The baseline patients features were similar between groups (VasQ treated/control). At baseline, preoperative arterial flow was similar; radial artery diameter at surgical site was 3.4 ± 0.8 mm in treated and 2.8 ± 0.5 mm in the control group. The mean arterial flow at 1 month was 480 ± 210 mL/min in treated and 561 ± 27 mL/min in the control group. At 3 months the mean arterial flow in treated was 645 ± 143 mL/min versus 824 ± 211 mL/min (p = 0.02) in the control group; at 6 months the arterial flow was 714 ± 146 mL/min versus 810 ± 194 mL/min (p = 0.05) in control group. The cardiac output flow at 6 months in the treated group was 4458 ± 928 mL/min versus 5599 ± 1355 mL/min (p = 0.05) in the control group. At 6 months the primary patency was 73% and 80% and the secondary patency 80% and 86% in treated compared to the control group, respectively. No VASQ device complications were recorded. CONCLUSION: The analysis of these data suggested that using VasQ device could be protective against the hemodynamic modification that occur during arteriovenous fistulae creation.

Right ventricular diastolic function in dialysis patients could be affected by vascular access.

Tricuspid annular plane excursion (TAPSE) measurement in echocardiography is a measure of heart diastolic distensibility: a low TAPSE indicates reduced ventricular distensibility leading to diastolic dysfunction. It is a good prognostic index for cardiac mortality risk in congestive heart failure patients, adding significant prognostic information to the NYHA clinical classification. Our study was designed to evaluate the effect of a single hemodialysis (HD) session on diastolic function and TAPSE, focusing on the effects of vascular access typology. Twenty chronically uremic patients (age 51 ± 10 years, dialytic age 24 ± 8 months), without overt heart disease, underwent conventional two-dimensional and Doppler echocardiography immediately before starting and 15 min after ending a mid-week HD session. Ten patients had distal radiocephalic arterovenous fistula (AVF), and 10 had permanent central venous catheters (CVC). The amount of fluid removed by HD was 2,706 ± 1,047 g/session. HD led to a reduction in TAPSE, left ventricle end-diastole volume, left ventricle end-systole volume, right ventricle end-diastole diameter, peak early transmitral flow velocity, and the ratio of early to late Doppler velocities of diastolic mitral flow. AVF patients showed greater right ventricle diameters versus CVC patients, while TAPSE appeared higher in the latter. Only the AVF patient group showed TAPSE values <15 mm. Our data confirm the effects of terminal uremia on right ventricle function (chamber dilation, impaired diastolic function), showing that these abnormalities are more frequent in AVF patients as opposed to CVC patients. It is reasonable to explain these clinical features as the effect of preload increase operated by AVF.

Genomic damage in endothelial progenitor cells from uremic patients in hemodialysis.

INTRODUCTION: End stage renal disease (ESRD) is associated with a high incidence of cardiovascular disease and cancer. Patients undergoing hemodialysis show a reduced number and an impaired function of endothelial progenitor cells (EPCs), which in physiological conditions contribute to repair the vascular damage. In patients with ESRD, massive oxidative genome damage has been demonstrated but the role of HD in causing it is still a controversial issue. The aim of our study was to analyze the effects of a single HD session on the number of cells marked with CD34 (including sub-type cells known to be EPCs); we then evaluated the genomic damage in these cells using COMET assay. PATIENTS AND METHODS: We quantified CD34(+) cells in blood samples in 30 patients in hemodiafiltration treatment for 3.5 to 4 hours 3 times/week and in 30 healthy volunteers. In HD patients, blood samples were drawn at different time intervals: start of dialysis (T(0)), at the end of the treatment (T(end)) and 24 hours afterwards in the interdialytic day (T(inter)). Staining and analysis was performed using the ISHAGE (International Society of Hematotherapy and Graft Engineering) guidelines. EPCs count was conducted using a multiparameter flow cytometric lyse no-wash method. Genomic damage was evaluated by Comet assay. RESULTS: The number of CD34(+) cells in the HD patients at the beginning of the dialysis session (T(0)) was significantly lower than in healthy controls. HD patients showed a significant increase in CD34 number at the end of the session (T(end)) with respect to T(0). In the interdialytic period (T(int)), the number of CD34(+) cells was significantly reduced with respect to T(end). COMET assay performed on CD34(+) cells showed a higher basal level of genomic damage in HD patients than in controls; it increased in a statistically significant manner after the hemodialysis session, while in the interdialytic period it came back to T(0) level. CONCLUSIONS: Uremic status is characterized by lower levels of circulating EPCs, which increase after a single session of HD together with genomic damage to the CD34(+) cells.

[Recurrent multifocal cancer lesions in a patient on hemodialysis after kidney pancreas transplant failure]. / Lesioni neoplastiche multifocali e recidivanti in un paziente in emodialisi dopo fallimento di trapianto combinato rene-pancreas.

Cancer is an important cause of mortality in patients on hemodialysis and kidney transplant recipients. Immunodepression and the genotoxic action of uremia are critical pathogenic agents. A 59-year-old man, ex-smoker, who had been on hemodialysis for seven months because of uremic degeneration of diabetic nephropathy, underwent a combined kidney-pancreas transplant in 1991, complicated by slow-resolution CMV infection. In 1993, after kidney graft failure due to chronic rejection, hemodialysis treatment was restarted with good pancreatic function. Steroid therapy was interrupted and azathioprine and cyclosporine immunosuppressive therapy maintained. In September 2007 the patient was diagnosed with two neoplasms of the oral mucosa: a well-differentiated squamous carcinoma and a spinocellular carcinoma associated with field cancerization. The tumors were resected, followed by laser treatment. Histological examination revealed squamous cell carcinoma without lymph node involvement. Azathioprine was interrupted. In January 2008 adjuvant radiotherapy to the surgical areas of the oral mucosa and neck was started. In February a verrucous nevus on the patient's chest turned out to be a spinocellular carcinoma in situ. In May 2008 recurrence of keratinizing squamous carcinoma of the oral mucosa was found, this time with nodal involvement. Cyclosporine administration was interrupted and after consultation with the oncology committee it was decided to continue with supportive therapy only, until the patient's death in August 2008.

Circadian rhythm of hydration in healthy subjects and uremic patients studied by bioelectrical impedance analysis.

BACKGROUND: Healthy subjects and patients after successful kidney transplantation show a circadian rhythm for glomerular filtration rate and for the glomerular transport of macromolecules. We aimed to evaluate by bioelectrical impedance analysis (BIA) whether body hydration status also follows a circadian rhythm in patients with impaired renal function. METHODS: The study was conducted on 28 subjects divided into 3 groups: 8 healthy volunteers, 8 patients affected by chronic kidney disease and 12 end-stage renal disease (ESRD) patients on hemodialysis. During 24 h, 9 BIA measurements were taken in every subject every 180 min. RESULTS: BIA findings demonstrate that normal subjects have a circadian rhythm in hydration status that reaches maximum body water content at night, between 21.00 and 23.00 h. In patients with chronic kidney disease, this rhythm, with maximum at night, is maintained. The rhythm is also present in ESRD patients, if the residual diuresis is at least 500 ml/day, while there is no rhythm when residual diuresis is <300 ml/day. CONCLUSIONS: In normal subjects, body hydration status shows a circadian rhythm, which is weakened or lost in oligoanuric patients on dialysis, but partially maintained in subjects with preterminal uremia and in hemodialyzed patients with residual diuresis >500 ml/day.

[Neprilysin inhibition and chronic kidney disease]. / Gli inibitori della Neprilisina nei pazienti affetti da Malattia Renale Cronica e Sindrome Cardio:Renale.

Patients with chronic kidney disease (CKD) have a higher incidence of cardiovascular (acute and chronic) events, which in turn have an increased risk of progression to end-stage renal disease (ESRD) Inhibition of neprilysin, in addition to offering a new therapeutic target in patients with heart failure, could represent a potential improvement strategy in cardiovascular and renal outcome of patients with CKD. Inhibition of neprilysin by inhibiting the breakdown of natriuretic peptides, increases their bioavailability resulting in an increase in diuresis and sodium excretion and, in addition to exerting an inhibition of the renin-angiotensin-aldosterone (RAAS) system. Inhibition of RAAS, in turn, generates a series of counter-regulations that can balance the adverse effects present in CKD and heart failure (HF). The idea of blocking neprilysin is not very recent, but the first drugs used as inhibitors had an inadmissible incidence of angioedema. Among the latest generation molecules that can perform a specific inhibitory action on the neprilysin receptor and, at the same time, on the angiotensin II receptor thanks to the association with valsartan there is the LCZ696 (sacubitril / valsartan). This drug has shown promising benefits both in the treatment arterial hypertension and heart failure. It is hoped that equally positive effects may occur in CKD patients, particularly those with macroproteinuria.