The management of high flow arteriovenous fistula and possible solutions.

BACKGROUND: The development of a high flow rate arteriovenous fistula (AVF) can expose the patient to development of heart failure due to increased cardiac preload and pulmonary hypertension. OBJECTIVES: AVF flow measurement (Qa) is considered a screening tool for AVF surveillance, aiming to evaluate the access dysfunction and prevent complications, like a non-maturation, suspected stenosis, high-flow AVF, and distal ischemia. In the upper arm AVF, a high Qa may develops, which can expose the patient to the risk of high-output heart failure and ischemia. Although, the exact threshold to define high-flow access is not universally accepted, AVF with a Qa of 1-1.5 L/min or cardio-pulmonary recirculation (Qa/CO) >20% are considered at risk. SUBJECTS: In our work we describe the treatment performed in three patients with high flow AVF treated with DRIL technique with interposition of a Prosthetic Patch, revascularization procedures such as distal inflow revision or RUDI and with innovative technique a "tench snout," removal the previous anastomosis and reconstruction of the integrity of the radial artery at the terminal in pre and post anastomosis. A PTFE prosthetic segment measuring 5 cm in length and 5 mm in diameter was interposed, terminally anastomosed with the efferent cephalic vein and terminally lateral with the radial artery, reducing the anastomosis to approximately 4 mm. RESULTS: All treated patients showed a clear improvement in the clinical picture in particularly heart failure. The calculation of the post-intervention flow rate approximately 1500 mL/min. CONCLUSION: The patient on hemodialysis with arteriovenous fistula must be constantly monitored with clinical examination, monitoring during the hemodialysis session and color Doppler ultrasound of the AVF with calculation of the flow rate. The surgical technique used for flow reduction is chosen on the surgical experience of each operator with the main objective of preserving the autologous AVF.

How to Assess the Glomerular Filtration Rate, and Which Method is Deemed Most Reliable?

The prevalence of chronic kidney disease (CKD) continues to rise globally, paralleled by an increase in associated morbidity and mortality, as well as significant implications for patient quality of life and national economies. Chronic kidney disease often progresses unrecognized by patients and physicians, despite diagnosis relying on two simple laboratory measures: estimated glomerular filtration rate (eGFR) and urine analysis. GFR measurement has been grounded in renal physiology, specifically the concept of clearance, with creatinine identified as a suitable endogenous marker for estimating creatinine clearance (CrCl). On this foundation, various equations have been developed to calculate CrCl or estimated GFR (eGFR) using four variables that incorporate creatinine and certain demographic information, such as sex and age. However, creatinine measurement requires standardization to minimize assay variability across laboratories. Moreover, the accuracy of these equations remains contentious in certain patient subgroups. For these reasons, additional mathematical models have been devised to enhance CrCl estimation, for example, when urine collection is impractical, in elderly or debilitated patients, and in individuals with trauma, diabetes, or obesity. Presently, eGFR in adults can be immediately measured and reported using creatinine-based equations traceable through isotope dilution mass spectrometry. In conclusion, leveraging insights from renal physiology, eGFR can be employed clinically for early diagnosis and treatment of CKD, as well as a public health tool to estimate its prevalence.

Renal Functional Reserve in Naïve HIV Patients.

Introduction. Renal functional reserve (RFR) is the kidney capability of increasing its basal glomerular filtration rate (GFR) at least 20% after an adequate stimulus. Renal disorders have been reported in seropositive HIV patients, particularly the decrease in glomerular filtration rate (eGFR), nephrotic syndrome, and proximal tubular deficiency associated with the disease itself or the use of some anti-retroviral treatments. Thus, it was decided to carry out a prospective study in order to evaluate if RFR test was preserved in naive HIV patients. Material and Method. GFR was measured by using cimetidine-aided creatinine clearance (CACC), and RFR as described Hellerstein et al. in seropositive naive HIV patients and healthy volunteers. Results. RFR was evaluated in 12 naïve HIV patients who showed positive RFR (24.8±2%), but significantly lower compared to RFR in 9 control individuals (90.3 ± 5%). Conclusion. In this study was found that renal functional reserve was positive in naïve HIV patients, but significantly lower compared to renal functional reserve achieved by seronegative healthy individuals.

[Steroid-Dependent Nephrotic Syndrome Due to Minimal Change Glomerulonephritis Treated with Rituximab].

47-year-old woman suffering from minimal lesion glomerulonephritis previously undergone high-dose steroid therapy and subjected to exacerbations of nephrotic syndrome after therapy discontinuation. It was decided to initiate off-label treatment with Rituximab at a dosage of 375 mg/m2 administred at zero-time, one-month and three months with good therapeutic response and resolution of the clinical laboratory picture. The therapy was well tolerated and had no side effects. This scheme could be an alternative to the conventional therapeutic scheme with steroids or other classes of immunosuppressive drugs, especially in order to avoid problems related to prolonged exposure to steroid therapy.

SARS-CoV-2 infection in kidney transplant recipients: Experience of the italian marche region.

BACKGROUND: Infection related to Coronavirus-19 (CoV-2) is pandemic affecting more than 4 million people in 187 countries worldwide. By May 10, 2020, it caused more than 280 000 deaths all over the world. Preliminary data reported a high prevalence of CoV-2 infection and mortality due to severe acute respiratory syndrome related CoV-2 (SARS-CoV-2) in kidney-transplanted patients (KTRs). Nevertheless, the outcomes and the best treatments for SARS-CoV-2-affected KTRs remain unclear. METHODS: In this report, we describe the clinical data, the treatments, and the outcomes of 5 KTRs with SARS-CoV-2 admitted to our hospital in Ancona, Marche region, Italy, from March 17 to present. Due to the severity of SARS-CoV-2, immunosuppression with calcineurin inhibitors, antimetabolites, and mTOR-inhibitors were stopped at the admission. All KTRs were treated with low-dose steroids. 4/5 KTRs were treated with hydroxychloroquine. All KTRs received tocilizumab up to one dose. RESULTS: Overall, the incidence of SARS-CoV-2 in KTRs in the Marche region was 0.85%. 3/5 were admitted in ICU and intubated. One developed AKI with the need of CRRT with Cytosorb. At present, two patients died, two patients were discharged, and one is still inpatient in ICU. CONCLUSIONS: The critical evaluation of all cases suggests that the timing of the administration of tocilizumab, an interleukin-6 receptor antagonist, could be associated with a better efficacy when administered in concomitance to the drop of the oxygen saturation. Thus, in SARS-CoV-2-affected KTRs, a close biochemical and clinical monitoring should be set up to allow physicians to hit the virus in the right moment such as a sudden reduction of the oxygen saturation and/or a significant increase in the laboratory values such as D-dimer.