The Current State of Nuclear Nephrology in Modern Medicine.

Glomerular filtration rate (GFR) is the most reliable parameter of renal function. Regarding the complexity of the gold standard inulin clearance, different estimating equations have been developed with CKD-EPI creatinine equation recommended as the most reliable one. In some clinical situations where creatinine based equations might not be valid, alternative methods are needed. Nuclear medicine methods for measuring GFR with 51Cr EDTA and 99mTc DTPA have been widely used for decades. There are different methodologies for the measurement of kidney function with radiopharmaceuticals: urinary clearance, plasma clearance, multiple plasma sampling, slope intercept, single sample plasma equation, slope only, and the gamma camera-based method. Greater precision of measuring GFR is needed in certain clinical situations. The most common are diagnosis and follow up of chronic kidney disease and definition of the beginning of replacement therapy. The assessment of renal function is also important for potential kidney donors. In recent years, with the introduction of new chemotherapeutic drugs and targeted therapy, oncologic patients treated with nephrotoxic drugs have become more commonly referred for measuring GFR. The monitoring of renal function is important during treatment in order to detect the transformation from reversible acute kidney injury to irreversible chronic kidney disease as well as in the cases of renal insufficiency reduce the dosage and prevent accumulation of the drug and avoid dosage related toxic effects. Assessment of kidney function using measured mGFR will be an important milestone in the creation of more accurate and expanding personalized medicine principle in current onconephrology practice.

Glomerulopathies with Fibrillary Deposits.

The glomerulopathies associated with the deposition of extracellular fibrils in the glomeruli are subdivided into Congo red positive (amyloidosis) and Congo red negative (non-amyloidotic glomerulopathies) based on Congo red staining. The non-amyloidotic glomerulopathies are divided into immunoglobulin-derived and non-immunoglobulin-derived glomerulopathies. The immunoglobulin-derived glomerulopathies: fibrillary glomerulopathy (FGn) and immunotactoid glomerulopathy (ITG) are rare glomerulopathies. The diagnosis of fibrillary-immunotactoid glomerulopathy depends on electron microscopy, which shows the presence of microfibrils in the glomeruli. The microfibrils in FGn are randomly arranged with diameters less than 30 nm. The microfibrils in ITG are larger than 30 nm with a visible lumen (microtubules), focally arranged in parallel bundles. Patients with fibrillary-immunotactoid glomerulopathy present with proteinuria (usually in the nephrotic range), microscopic hematuria, arterial hypertension, and chronic kidney disease that progresses to kidney failure over months to years. Currently, there are no guidelines for the treatment of fibrillary-immunotactoid glomerulopathy, although immunotactoid glomerulopathy could be associated with underlying hematologic disorders with the need for clone-directed therapy.

Percutaneous Onsite Insertion of Catheter for Peritoneal Dialysis - A New Method Introduction in the Country.

Peritoneal dialysis (PD) is one of the options for renal replacement therapy (RRT) in the end stage renal disease (ESRD) patients. Compared to hemodialysis (HD), patients on PD experience a greater sense of well-being, an improved steady state in terms of extracellular fluid volume shifts and hemodynamics and it is preferred method for patients with problematic vascular access, bleeding tendencies, heart failure and elderly patients. In order to perform PD, a tunneled catheter should be placed through the abdominal wall and into peritoneal space, with positioning of the catheter within the most dependent portion of pelvis. Currently, there are several techniques available for PD catheter placement: open surgery, laparoscopic and percutaneous. We present for the first time in our country a case of 65 year old male patient to whom percutaneous onsite insertion of peritoneal catheter was performed. The idea is to emphasize that sometimes this should be a method of choice for RRT, especially in patients where general anesthesia should be avoid. Compared to other methods, percutaneous insertion is a simple procedure with no need for general anesthesia, and the benefits of quick recovery, earlier ambulation, and less delay in catheter placement.

The blood flow rate on the first day after arteriovenous fistula creation is a predictor of successful fistula maturation.

BACKGROUND: The determination of blood flow rate (BFR) is a useful tool for assessing the function of arteriovenous fistula (AVF). METHODS: Eighty patients with a newly created radio cephalic AVF were analyzed. Hemodynamics and morphological characteristics of the blood vessels were assessed by Doppler ultrasound. RESULTS: The mean age of patients was 59.9 ± 13.5 years. A successful rate of AVF maturation was 62.5% at 8 weeks. Six adjusted models of multivariate analysis showed that BFR at Day 1 was a predictor for AVF maturation both at 4 weeks (p < 0.001) and 8 weeks (p < 0.001). Receiver operating characteristic analysis showed an optimal cut-off point for BFR at Day 1 of 395 ml/min for successful maturation at 4 weeks (sensitivity 0.714, specificity 0.889) and 344 ml/min for successful maturation at 8 weeks (sensitivity 0.860, specificity 0.867). CONCLUSION: BFR at Day 1 is a powerful predictor for successful AVF maturation at 4 and 8 weeks.

Percutaneous Nephrostomy in the Treatment of Hydronephrosis in Renal Transplant Patients - Case Report.

Percutaneous nephrostomy is a first-line minimal invasive treatment option for ureteral obstruction following kidney transplantation, with high effectiveness and a low complication rate. Percutaneous nephrostomy might be used as a temporary salvage therapy, providing acute decompression of the kidney collecting system and preventing graft loss. It can also function as a permanent and sometimes only possible option in transplant patients with frequent recurrences of ureteral stenosis who either fail an open surgical reconstruction or who are not good candidates for these procedures. We present two patients with acute decline in urine output after renal transplantation with radiologically verified hydroureteronephrosis of the transplanted kidney (graft) caused by stenosis of distal ureter. In both cases, nephrostomy was placed within 48 hours as a temporary salvage treatment that ameliorates renal function and prevents graft loss. The permanent nephrostomy was the only possible solution for the preservation of the graft's function in the first case because of the recurrences of ureteral stenosis after several percutaneous interventions and open-surgery ureteral reconstruction. A few episodes of nephrostomy tube-related infections were resolved with antibiotics in the first case. The second case was treated with open ureteroneocystostomy with resection of stenotic segment and reinsertion of the ureter into the bladder (ureterocystoneostomy) because of the length of the involved ureteral segment. Both patients had stable graft function in the follow-up period.

Pharmacotherapeutic options for the prevention of kidney transplant rejection: the evidence to date.

INTRODUCTION: Although early rejection episodes are successfully controlled, the problem of unrecognized production of de novo anti-HLA antibodies and associated chronic rejection still persists. AREAS COVERED: In addition to the standard induction and maintenance therapy, we present a couple of new drugs as induction (Alemtuzumab), CNI-free protocol (Belatacept, Sirolimus, and Everolimus), and maintenance treatment in transplant patients with various types of malignancies (T cell-targeted immunomodulators blocking the immune checkpoints CTLA-4 and PD1/PDL1) and TMA (aHUS)-eculizumab and IL6 receptor antagonists in antibody-mediated rejection (AMR). EXPERT OPINION: There are a couple of issues still preventing improvement in kidney transplant long-term outcomes with current and anticipated future immunosuppression: patients more susceptible to infection and CNI nephrotoxicity in kidneys obtained from elderly donors and highly sensitized patients with limited chances to get appropriate kidney and a higher risk for late AMR. A lower rate of CMV/BK virus infections has been observed in everolimus-treated patients. Belatacept use has been justified only in EBV-seropositive kidney transplants due to the increased risk of PTLD. Eculizumab upon recurrence of aHUS is a sole cost-effective option. A new IL-6 blocking drug (clazakizumab/tocilizumab) is a promising option for prevention/treatment of AMR. Clinical experience in tailoring immunosuppression for improving as long as possible graft and patient survival is inevitable.