Reclassification of membranoproliferative glomerulonephritis: Identification of a new GN: C3GN

This review revises the reclassification of the membranoproliferative glomerulonephritis (MPGN) after the consensus conference that by 2015 reclassified all the glomerulonephritis basing on etiology and pathogenesis, instead of the histomorphological aspects. After reclassification, two types of MPGN are to date recognized: The immunocomplexes mediated MPGN and the complement mediated MPGN. The latter type is more extensively described in the review either because several of these entities are completely new or because the improved knowledge of the complement cascade allowed for new diagnostic and therapeutic approaches. Overall the complement mediated MPGN are related to acquired or genetic cause. The presence of circulating auto antibodies is the principal acquired cause. Genetic wide association studies and family studies allowed to recognize genetic mutations of different types as causes of the complement dysregulation. The complement cascade is a complex phenomenon and activating factors and regulating factors should be distinguished. Genetic mutations causing abnormalities either in activating or in regulating factors have been described. The diagnosis of the complement mediated MPGN requires a complete study of all these different complement factors. As a consequence, new therapeutic approaches are becoming available. Indeed, in addition to a nonspecific treatment and to the immunosuppression that has the aim to block the auto antibodies production, the specific inhibition of complement activation is relatively new and may act either blocking the C5 convertase or the C3 convertase. The drugs acting on C3 convertase are still in different phases of clinical development and might represent drugs for the future. Overall the authors consider that one of the principal problems in finding new types of drugs are both the rarity of the disease and the consequent poor interest in the marketing and the lack of large international cooperative studies.

Are phosphodiesterase type 5 inhibitors effective for the management of lower urinary symptoms suggestive of benign prostatic hyperplasia?

AIM: To review the efficacy of phosphodiesterase type 5 inhibitors (PDE5-Is) in lower urinary tract symptoms (LUTS) suggestive of benign prostate hyperplasia (LUTS/BPH).

METHODS: A comprehensive research was conducted to identify all publications relating to benign prostate hyperplasia and treatment with sildenafil, vardenafil and tadalafil. To assess the efficacy, the changes in total international prostate symptom score (IPSS), IPSS subscore including voiding, storage and quality of life (QoL), Benign prostatic hyperplasia Impact Index (BII), maximum urinary flow rate (Qmax) and the International Index of Erectile Function (IIEF) were extracted. A meta-analytical technique was used for the analysis of integrated data from the included studies to evaluate the mean difference in the results.

RESULTS: Total IPSS score, IIEF and BII showed a significant improvement in trials in which LUTS/BPH with or without erectile dysfunction (ED) were compared with the placebo. For LUTS/BPH, the mean differences of total IPSS score, IIEF and BII are -2.17, 4.88 and -0.43, P < 0.00001, respectively. For LUTS/BPH with comorbid ED, the mean difference are -1.97, 4.54 and -0.52, P < 0.00001, respectively. PDE5-Is appear to improve IPSS storage, voiding and QoL subscore (mean difference = -0.71, -1.23 and -0.33, P < 0.00001, respectively). Although four doses of tadalafil (2.5, 5, 10 and 20 mg) failed to reach significance in Qmax (mean difference = 0.22, P = 0.10), the 5 mg dose of tadalafil significantly improved the Qmax (mean difference = 0.33, P = 0.03).

CONCLUSION: PED5-Is demonstrated efficacy for improving LUTS in BPH patients with or without ED and could be considered to be the first line treatment for LUTS/BPH.

Treatment of young patients with lupus nephritis using calcineurin inhibitors

Recent advances in the management of lupus nephritis, together with earlier renal biopsy and selective use of aggressive immunosuppressive therapy, have contributed to a favorable outcome in children and adolescents with systemic lupus erythematosus (SLE). Nevertheless, we believe that a more effective and less toxic treatment is needed to attain an optimal control of the activity of lupus nephritis. Recent published papers and our experiences regarding treatment of young patients with lupus nephritis using calcineurin inhibitors are reviewed. Although it has been reported that intermittent monthly pulses of intravenous cyclophosphamide (IVCY) are effective for preserving renal function in adult patients, CPA is a potent immunosuppressive agent that induces severe toxicity, including myelo- and gonadal toxicity, and increases the risk of secondary malignancy. Thus, treatment for controlling lupus nephritis activity, especially in children and adolescents, remains challenging. Cyclosporine A (CsA) and tacrolimus (Tac) are T-cell-specific calcineurin inhibitors that prevent the activation of helper T cells, thereby inhibiting the transcription of the early activation genes of interleukin (IL)-2 and suppressing T cell-induced activation of tumor necrosis factor-α, IL-1β and IL-6. Therefore, both drugs, which we believe may be less cytotoxic, are attractive therapeutic options for young patients with lupus nephritis. Recently, a multidrug regimen of prednisolone (PDN), Tac, and mycophenolate mofetile (MMF) has been found effective and relatively safe in adult lupus nephritis. Since the mechanisms of action of MMF and Tac are probably complementary, multidrug therapy for lupus nephritis may be useful. We propose as an alternative to IVCY, a multidrug therapy with mizoribine, which acts very similarly to MMF, and Tac, which has a different mode of action, combined with PDN for pediatric-onset lupus nephritis. We also believe that a multidrug therapy including CsA and Tac may be an attractive option for young patients with SLE and lupus nephritis.

Prostatic surgery associated acute kidney injury

Acute kidney injury (AKI) is associated with extended hospital stays, high risks of in-hospital and long-term mortality, and increased risk of incident and progressive chronic kidney disease. Patients with urological diseases are a high-risk group for AKI owing to the coexistence of obstructive uropathy, older age, and preexistent chronic kidney disease. Nonetheless, precise data on the incidence and outcomes of postoperative AKI in urological procedures are lacking. Benign prostatic hyperplasia and prostate cancer are common diagnoses in older men and are frequently treated with surgical procedures. Whereas severe AKI after prostate surgery in general appears to be unusual, AKI associated with transurethral resection of the prostate (TURP) syndrome and with rhabdomyolysis (RM) after radical prostatectomy have been frequently described. The purpose of this review is to discuss the current knowledge regarding the epidemiology, risk factors, outcomes, prevention, and treatment of AKI associated with prostatic surgery. The mechanisms of TURP syndrome and RM following prostatic surgeries will be emphasized.

Update on immunoglobulin A nephropathy, Part I: Pathophysiology

Immunoglobulin A (IgA) nephropathy is one of the most common glomerulonephritis and its frequency is probably underestimated because in most patients the disease has an indolent course and the kidney biopsy is essential for the diagnosis. In the last years its pathogenesis has been better identified even if still now several questions remain to be answered. The genetic wide association studies have allowed to identifying the relevance of genetics and several putative genes have been identified. The genetics has also allowed explaining why some ancestral groups are affected with higher frequency. To date is clear that IgA nephropathy is related to auto antibodies against immunoglobulin A1 (IgA1) with poor O-glycosylation. The role of mucosal infections is confirmed, but which are the pathogens involved and which is the role of Toll-like receptor polymorphism is less clear. Similarly to date whether the disease is due to the circulating immunocomplexes deposition on the mesangium or whether the antigen is already present on the mesangial cell as a "lanthanic" deposition remains to be clarified. Finally also the link between the mesangial and the podocyte injury and the tubulointerstitial scarring, as well as the mechanisms involved need to be better clarified.

Asymptomatic hyperuricemia following renal transplantation

Evidence is accumulating indicating a role for uric acid in the genesis and progression of kidney disease, and a few studies are beginning to show a possible beneficial effect of urate-lowering therapy. Whether this holds true for renal allograft recipients is not clear. In this short review evidence from epidemiological as well as intervention studies is summarized and discussed, with some practical considerations presented at the end.

Outcomes of renal transplant recipients with BK virus infection and BK virus surveillance in the Auckland region from 2006 to 2012

AIM

To evaluate incidence, risk factors and treatment outcome of BK polyomavirus nephropathy (BKVN) in a cohort of renal transplant recipients in the Auckland region without a formal BK polyomavirus (BKV) surveillance programme.

METHODS

A cohort of 226 patients who received their renal transplants from 2006 to 2012 was retrospectively reviewed.

RESULTS

Seventy-six recipients (33.6%) had a BK viral load (BKVL) test and 9 patients (3.9%) developed BKVN. Cold ischaemia time (HR = 1.18, 95%CI: 1.04-1.35) was found to be a risk factor for BKVN. Four recipients with BKVN had complete resolution of their BKV infection; 1 recipient had BKVL less than 625 copies/mL; 3 recipients had BKVL more than 1000 copies/mL and 1 had graft failure from BKVN. BKVN has a negative impact on graft function [median estimated glomerular filtration rate (eGFR) 22.5 (IQR 18.5-53.0) mL/min per 1.73 m², P = 0.015), but no statistically significant difference (P = 0.374) in renal allograft function was found among negative BK viraemia group [median eGFR 60.0 (IQR 48.5-74.2) mL/min per 1.73 m²), positive BK viraemia without BKVN group [median eGFR 55.0 (IQR 47.0-76.0) mL/min per 1.73 m²] and unknown BKV status group [median eGFR 54.0 (IQR 43.8-71.0) mL/min per 1.73 m²]. The incidence and treatment outcomes of BKVN were similar to some centres with BKV surveillance programmes.

CONCLUSION

Recipients with BVKN have poorer graft function. Although active surveillance for BKV has been shown to be effective in reducing incidence of BKVN, it should be tailored specifically to that transplant centre based on its epidemiology and outcomes of BKVN, particularly in centres with limited resources.

Obstructive uropathy – acute and chronic medical management

Obstructive uropathy is an important cause of acute and chronic kidney disease. Decompression of the urinary tract is an essential aspect of treatment. The cause and aetiology of obstruction typically determine the surgical approach. Acute relief of obstruction is frequently complicated by fluid and electrolyte imbalance. Standard therapeutic interventions for acute or chronic renal failure also apply for cases of obstructive uropathy. This narrative review summarises the early and long-term medical management of obstructive uropathy.

Metformin associated lactic acidosis in Auckland City Hospital 2005 to 2009

AIM

To determine the incidence, clinical characteristics and outcomes of patients with metformin associated lactic acidosis (MALA).

METHODS

Auckland City Hospital drains a population of just over 400000 people. All cases presenting with metabolic acidosis between July 2005 and July 2009 were identified using clinical coding. A retrospective case notes review identified patients with MALA. Prescribing data for metformin was obtained from the national pharmaceutical prescribing scheme.

RESULTS

There were 42 cases of metabolic lactic acidosis over 1718000 patient years. There were 51000 patient years of metformin prescribed to patients over the study period. There were thirty two cases of lactic acidosis due to sepsis, seven in patients treated with metformin. Ten cases of MALA were identified. The incidence of MALA was estimated at 19.46 per 100000 patient year exposure to metformin. The relative risk of lactic acidosis in patients on metformin was 13.53 (95%CI: 7.88-21.66) compared to the general population. The mean age of patients with MALA was 63 years, range 40-83 years. A baseline estimated glomerular filtration rate was obtained in all patients and ranged from 23-130 mL/min per 1.73 m(2). Only two patients had chronic kidney disease G4. Three patients required treatment with haemodialysis. Two patients died.

CONCLUSION

Lactic acidosis is an uncommon but significant complication of use of metformin which carries a high risk of morbidity.

Liposoluble vitamins A and E in kidney disease

Kidney disease (KD) is characterized by the presence of elevated oxidative stress, and this is postulated as contributing to the high cardiovascular morbidity and mortality in these individuals. Chronic KD (CKD) is related to high grade inflammatory condition and pro-oxidative state that aggravates the progression of the disease by damaging primary podocytes. Liposoluble vitamins (vitamin A and E) are potent dietary antioxidants that have also anti-inflammatory and antiapoptotic functions. Vitamin deficits in CKD patients are a common issue, and multiple causes are related to them: Anorexia, dietary restrictions, food cooking methods, dialysis losses, gastrointestinal malabsorption, etc. The potential benefit of retinoic acid (RA) and α-tocopherol have been described in animal models and in some human clinical trials. This review provides an overview of RA and α tocopherol in KD.

Role of renal proximal tubule transport in thiazolidinedione-induced volume expansion

Thiazolidinediones (TZDs), pharmacological activators of peroxisome-proliferator-activated receptors γ (PPARγ), significantly improve insulin resistance and lower plasma glucose concentrations. However, the use of TZDs is associated with plasma volume expansion, the mechanism of which has been a matter of controversy. Originally, PPARγ-mediated enhanced transcription of the epithelial Na channel (ENaC) γ subunit was thought to play a central role in TZD-induced volume expansion. However, later studies suggested that the activation of ENaC alone could not explain TZD-induced volume expansion. We have recently shown that TZDs rapidly stimulate sodium-coupled bicarbonate absorption from renal proximal tubule (PT) in vitro and in vivo. TZD-induced transport stimulation was dependent on PPARγ/Src/EGFR/ERK, and observed in rat, rabbit and human. However, this stimulation was not observed in mouse PTs where Src/EGFR is constitutively activated. Analysis in mouse embryonic fibroblast cells confirmed the existence of PPARγ/Src-dependent non-genomic signaling, which requires the ligand binding ability but not the transcriptional activity of PPARγ. The TZD-induced enhancement of association between PPARγ and Src supports an obligatory role for Src in this signaling. These results support the view that TZD-induced volume expansion is multifactorial. In addition to the PPARγ-dependent enhanced expression of the sodium transport system(s) in distal nephrons, the PPARγ-dependent non-genomic stimulation of renal proximal transport may be also involved in TZD-induced volume expansion.

Renal transplant recipient seizure practical management

Seizures are not uncommon in renal transplant patients. The common aetiologies are metabolic disturbance associated with renal failure, immunosuppression and associated complications and infections. Their management can be challenging because of altered pharmacokinetics of antiepileptic drugs (AEDs) and their removal by dialysis. A practical approach to the management of seizure in renal transplant patients is discussed. This review highlights the guidelines for use of various AEDs in renal transplants.

Evidence-based medicine: An update on treatments for peritoneal dialysis-related peritonitis

Peritonitis continues to be a major complication of peritoneal dialysis (PD), and adequate treatment is crucial for a favorable outcome. There is no consensus regarding the optimal therapeutic regimen, and few prospective controlled studies have been published. The objective of this manuscript is to review the results of PD peritonitis treatment reported in narrative reviews, systematic reviews, and proportional meta-analyses. Two narrative reviews, the only existing systematic review and its update published between 1991 and 2014 were included. In addition, we reported the results of a proportional meta-analysis published by our group. Results from systematic reviews of randomized control trials (RCT) and quasi-RCT were not able to identify any optimal antimicrobial treatment, but glycopeptide regimens were more likely to achieve a complete cure than a first generation cephalosporin. Compared to urokinase, simultaneous catheter removal and replacement resulted in better outcomes. Continuous and intermittent IP antibiotic use had similar outcomes. Intraperitoneal antibiotics were superior to intravenous antibiotics in reducing treatment failure. In the proportional meta-analysis of RCTs and the case series, the resolution rate (86%) of ceftazidime plus glycopeptide as initial treatment was significantly higher than first generation cephalosporin plus aminoglycosides (66%) and glycopeptides plus aminoglycosides (75%). Other comparisons of regimens used for either initial treatment or treatment of gram-positive rods or gram-negative rods did not show statistically significant differences. The superiority of a combination of a glycopeptide and a third generation cephalosporin was also reported by a narrative review study published in 1991, which reported an 88% resolution rate.

Kidney function outcomes following thermal ablation of small renal masses

The diagnosis of small renal masses (SRMs) continues to increase likely attributable to widespread use of axial cross-sectional imaging. Many of these SRMs present in elderly patients with abnormal baseline renal function. Such patients are at risk for further decline following therapeutic intervention. Renal thermal ablation presents one approach for management of SRMs whereby tumors are treated in situ without need for global renal ischemia. These treatment characteristics contribute to favorable renal function outcomes following kidney tumor ablation particularly in patients with an anatomic or functional solitary renal unit.

Regulatory roles of nitric oxide and angiotensin II on renal tubular transport

Renal tubules regulate blood pressure and humoral homeostasis. Mediators that play a significant role in regulating the transport of solutes and water include angiotensin II (AngII) and nitric oxide (NO). AngIIcan significantly raise blood pressure via effects on the heart, vasculature, and renal tubules. AngII generally stimulates sodium reabsorption by triggering sodium and fluid retention in almost all segments of renal tubules. Stimulation of renal proximal tubule (PT) transport is thought to be essential for AngII-mediated hypertension. However, AngII has a biphasic effect on in vitro PT transport in mice, rats, and rabbits: stimulation at low concentrations and inhibition at high concentrations. On the other hand, NO is generally thought to inhibit renal tubular transport. In PTs, NO seems to be involved in the inhibitory effect of AngII. A recent study reports a surprising finding: AngII has a monophasic stimulatory effect on human PT transport. Detailed analysis of signalling mechanisms indicates that in contrast to other species, the human NO/guanosine 3’,5’-cyclic monophosphate/extracellular signal-regulated kinase pathway seems to mediate this effect of Ang II on PT transport. In this review we will discuss recent progress in understanding the effects of AngII and NO on renal tubular transport.

Fluid overload as a major target in management of cardiorenal syndrome: Implications for the practice of peritoneal dialysis

Congestion is an integral component of cardiorenal syndrome and portends an adverse impact on the outcomes. Recent studies suggest that congestion has the ability of modulating the interactions between the kidney and the heart in this setting. Peritoneal dialysis (PD) is a home-based therapeutic modality that is not only offered to patients with end-stage renal disease to provide solute clearance and ultrafiltration, but it has also been used in patients with refractory heart failure and fluid overload to help optimize volume status. Several uncontrolled studies and case series have so far evaluated the role of PD in management of hypervolemia for patients with heart failure. They have generally reported favorable results in this setting. However, the data on the outcomes of patients with end-stage renal disease and concomitant heart failure is mixed, and the proposed theoretical advantages of PD might not translate into improved clinical endpoints. Congestion is prevalent in this patient population and has a significant effect on their survival. As studies suggest that a significant subset of patients with end-stage renal disease who receive PD therapy are hypervolemic, suboptimal management of congestion could at least in part explain these conflicting results. PD is a highly flexible therapeutic modality and the choice of techniques, regimens, and solutions can affect its ability for optimization of fluid status. This article provides an overview of the currently available data on the role and clinical relevance of congestion in patients with cardiorenal syndrome and reviews potential options to enhance decongestion in these patients.

Application of established pathophysiologic processes brings greater clarity to diagnosis and treatment of hyponatremia

Hyponatremia, serum sodium < 135 mEq/L, is the most common electrolyte abnormality and is in a state of flux. Hyponatremic patients are symptomatic and should be treated but our inability to consistently determine the causes of hyponatremia has hampered the delivery of appropriate therapy. This is especially applicable to differentiating syndrome of inappropriate antidiuresis (SIAD) from cerebral salt wasting (CSW) or more appropriately, renal salt wasting (RSW), because of divergent therapeutic goals, to water-restrict in SIAD and administer salt and water in RSW. Differentiating SIAD from RSW is extremely difficult because of identical clinical parameters that define both syndromes and the mindset that CSW occurs rarely. It is thus insufficient to make the diagnosis of SIAD simply because it meets the defined characteristics. We review the pathophysiology of SIAD and RSW, the evolution of an algorithm that is based on determinations of fractional excretion of urate and distinctive responses to saline infusions to differentiate SIAD from RSW. This algorithm also simplifies the diagnosis of hyponatremic patients due to Addison’s disease, reset osmostat and prerenal states. It is a common perception that we cannot accurately assess the volume status of a patient by clinical criteria. Our algorithm eliminates the need to determine the volume status with the realization that too many factors affect plasma renin, aldosterone, atrial/brain natriuretic peptide or urine sodium concentration to be useful. Reports and increasing recognition of RSW occurring in patients without evidence of cerebral disease should thus elicit the need to consider RSW in a broader group of patients and to question any diagnosis of SIAD. Based on the accumulation of supporting data, we make the clinically important proposal to change CSW to RSW, to eliminate reset osmostat as type C SIAD and stress the need for a new definition of SIAD.

Hepcidin-25 negatively predicts left ventricular mass index in chronic kidney disease patients

AIM: To assess the correlation between the serum hepcidin-25 level and left ventricular mass index.

METHODS: This study was a cross-sectional study conducted between March 2009 and April 2010. Demographic and biochemical data, including the serum hepcidin-25 level, were collected for chronic kidney disease (CKD) patients. Two-dimensional echocardiography was performed to determine the left ventricle mass (LVM), left ventricular mass index (LVMI), interventricular septum thickness (IVSd), left ventricle posterior wall thickness (LVPW), right ventricular dimension (RVD), left atrium (LA) and ejection fraction (EF).

RESULTS: A total of 146 patients with stage 1 to 5 CKD were enrolled. Serum hepcidin-25 levels were 16.51 ± 5.2, 17.59 ± 5.32, 17.38 ± 6.47, 19.98 ± 4.98 and 22.03 ± 4.8 ng/mL for stage 1 to 5 CKD patients, respectively. Hepcidin-25 level was independently predicted by the serum ferritin level (β = 0.6, P = 0.002) and the estimated glomerular filtration rate (β = -0.48, P = 0.04). There were negative correlations between the serum hepcidin level and the LVM and LVMI (P = 0.04 and P = 0.005, respectively). Systolic blood pressure (BP) was positively correlated with the LVMI (P = 0.005). In the multivariate analysis, a decreased serum hepcidin-25 level was independently associated with a higher LVMI (β = -0.28, 95%CI: -0.48 - -0.02, P = 0.006) after adjusting for body mass index, age and systolic BP.

CONCLUSION: A lower serum hepcidin level is associated with a higher LVMI in CKD patients. Low hepcidin levels may be independently correlated with unfavorable cardiovascular outcomes in this population.

FGF23 and inflammation

Systemic inflammation is a recognized feature in chronic kidney disease (CKD). The role of systemic inflammation in the pathogenesis of vascular calcification was recently settled. FGF23 was recently accused as a direct stimulus of systemic inflammation. This finding explains the strong association of FGF23 to vascular calcification and increased mortality among CKD.

Broad spectrum of interferon-related nephropathies-glomerulonephritis, systemic lupus erythematosus-like syndrome and thrombotic microangiopathy: A case report and review of literature

BACKGROUND

Interferons (IFNs) are characterized by a wide range of biological effects, which justifies their potential therapeutic use in several pathologies, but also elicit a wide array of adverse effects in almost every organ system. Among them, renal involvement is probably one of the most complex to identify.

CASE SUMMARY

We describe four cases of kidney damage caused by different IFN formulations: IFN-β-related thrombotic microangiopathy, IFN-β-induced systemic lupus erythematosus, and two cases of membranous nephropathy secondary to pegylated-IFN-α 2B. In each case, we carefully excluded any other possible cause of renal involvement. Once suspected as the casual relationship between drug and kidney damage, IFN treatment was immediately discontinued. In three cases, we observed a complete and persistent remission of clinical and laboratory abnormalities after IFN withdrawal, while the patient who developed thrombotic microangiopathy, despite IFN withdrawal and complement-inhibitor therapy with eculizumab, showed persistent severe renal failure requiring dialysis.

CONCLUSION

This case series highlights the causal relationship between IFN treatment and different types of renal involvement and enables us to delineate several peculiarities of this association.

Functional coupling of V-ATPase and CLC-5

Dent’s disease is an X-linked renal tubulopathy characterized by low molecular weight proteinuria, hypercalciuria and progressive renal failure. Disease aetiology is associated with mutations in the CLCN5 gene coding for the electrogenic 2Cl^-/H⁺ antiporter chloride channel 5 (CLC-5), which is expressed in the apical endosomes of renal proximal tubules with the vacuolar type H⁺-ATPase (V-ATPase). Initially identified as a member of the CLC family of Cl^- channels, CLC-5 was presumed to provide Cl^- shunt into the endosomal lumen to dissipate H⁺ accumulation by V-ATPase, thereby facilitating efficient endosomal acidification. However, recent findings showing that CLC-5 is in fact not a Cl^- channel but a 2Cl^-/H⁺ antiporter challenged this classical shunt model, leading to a renewed and intense debate on its physiological roles. Cl^- accumulation via CLC-5 is predicted to play a critical role in endocytosis, as illustrated in mice carrying an artificial Cl^- channel mutation E211A that developed defective endocytosis but normal endosomal acidification. Conversely, a recent functional analysis of a newly identified disease-causing Cl^- channel mutation E211Q in a patient with typical Dent’s disease confirmed the functional coupling between V-ATPase and CLC-5 in endosomal acidification, lending support to the classical shunt model. In this editorial, we will address the current recognition of the physiological role of CLC-5 with a specific focus on the functional coupling of V-ATPase and CLC-5.

Albuminuria as a marker of arterial stiffness in chronic kidney disease patients

AIM: To access the association between albuminuria levels and arterial stiffness in non-diabetic patients with hypertension and chronic kidney disease (CKD) stages 1-2, treated with renin angiotensin blockade agents plus other hypertensive drugs when needed.

METHODS: One hundred fifteen patients [median age 52 years (68% males)] were consequently enrolled in the study. For each patient, we recorded gender, age, body mass index (BMI), peripheral systolic blood pressure (pSBP), peripheral diastolic blood pressure, peripheral pulse pressure, central systolic blood pressure (cSBP), central diastolic blood pressure (cDBP), central pulse pressure (cPP), hematocrit, hemoglobin, hsCRP, total cholesterol triglycerides, high-density lipoprotein-C, low-density lipoprotein-C, calcium, phosphorus, parathormone, and albumin, as well as 24 h urine albumin excretion. According to 24-h urine albumin collection, patients were then classified as those with moderately increased albuminuria (formerly called macroalbuminuria) (≤ 300 mg/d) and those with severely increased albuminuria (formerly called macroaluminuria (> 300 mg/d). We considered aortic stiffness (AS) indices [carotid femoral pulse wave velocity (PWVc-f) and augmentation index (AIx)] as primary outcomes of the study. We explored potential correlations between severely increased albuminuria and AS indices using a multiple linear regression model.

RESULTS: Fifty-eight patients were included in the moderately increased albuminuria group and 57 in the severely increased albuminuria. Blood pressure measurements of the study population were 138 ± 14/82 ± 1.3 mmHg (systolic/diastolic). There were no significant differences in age, sex, and BP measurements between the two groups. Patients with severely increased albuminuria had higher PWV and AIx than patients with moderately increased albuminuria (P < 0.02, P < 0.004, respectively). In addition these patients exhibited higher BMI (P < 0.03), hsCRP (P < 0.001), and fibrinogen levels (P < 0.02) compared to patients with moderately increased albuminuria. In multivariate linear regression analysis, severely increased albuminuria (β = 1.038, P < 0.010) pSBP (β = 0.028, P < 0.034) and Ht (β = 0.171, P = 0.001) remained independent determinants of the increased PWVc-f. Similarly, severely increased albuminuria (β = 4.385, P < 0.012), cSBP (β = 0.242, P < 0.001), cPP (β = 0.147, P < 0.01) and Ht levels (β = 0.591, P < 0.013) remained independent determinants of increased AIx.

CONCLUSION: These findings demonstrate an independent association between AS indices and severely increased albuminuria in non-diabetic, hypertensive patients with CKD stages 1-2 treated with renin angiotensin aldosterone system blockers.

Pharmacokinetic and pharmacodynamic considerations of antimicrobial drug therapy in cancer patients with kidney dysfunction

Patients with cancer have a high inherent risk of infectious complications. In addition, the incidence of acute and chronic kidney dysfunction rises in this population. Anti-infective drugs often require dosing modifications based on an estimate of kidney function, usually the glomerular filtration rate (GFR). However, there is still no preferential GFR formula to be used, and in acute kidney injury there is always a considerable time delay between true kidney function and estimated GFR. In most cases, the anti-infective therapy should start with an immediate and high loading dose. Pharmacokinetic as well as pharmacodynamic principles must be applied for further dose adjustment. Anti-infective drugs with time-dependent action should be given with the target of high trough concentrations (e.g., beta lactam antibiotics, penems, vancomycin, antiviral drugs). Anti-infective drugs with concentration-dependent action should be given with the target of high peak concentrations (e.g., aminoglycosides, daptomycin, colistin, quinolones). Our group created a pharmacokinetic database, called NEPharm, hat serves as a reference to obtain reliable dosing regimens of anti-infective drugs in kidney dysfunction as well as renal replacement therapy. To avoid the risk of either too low or too infrequent peak concentrations, we prefer the eliminated fraction rule for dose adjustment calculations.

Serum phosphate and chronic kidney and cardiovascular disease: Phosphorus potential implications in general population

It has already been established that in end-stage renal disease, hyperphosphatemia causes soft tissue calcification including vascular calcifications. It has also been supported that there is a connection between increased serum phosphate and morbidity in subjects, who suffer from renal disease. However, studies in these populations conferred mixed results. Several warnings are included in the role of serum phosphorus on cardiovascular disease in normal populations. Homeostasis of serum phosphate is obtained by the cooperation between regulatory hormones, cellular receptors and bone metabolic factors. There is the probability that one or more phosphate regulatory factors, rather than phosphate directly, may be responsible for observed associations with calcification and cardiovascular events in normal populations. Experimental studies have shown that the restriction of dietary phosphate prevents the progression of kidney dysfunction, although high dietary phosphate aggravates the renal function. In the current review, we discuss the role of serum phosphorus on progression of renal dysfunction and cardiovascular outcomes in chronic kidney disease patients and its involvement in important health risks in the general population.

Six end-stage renal disease patients benefited from first non-simultaneous single center 6-way kidney exchange transplantation in India

AIM

To avoid desensitization protocols and ABO incompatible kidney transplantation (KT) due to high costs and increased risk of infections from intense immunosuppression.

METHODS

We present institutional ethical review board - approved study of single center 6-way kidney exchange transplantation. The participants comprised ABO incompatibility (n = 1); positive cross-match and/or presence of donor specific antibody (n = 5). The average time required from registration in kidney paired donation (KPD) registry to find suitable donors was 45 d and time required to perform transplants after legal permission was 2 mo.

RESULTS

Graft and patient survival were 100%, and 100%, respectively. One patient had biopsy-proven acute borderline T cell rejection (Banff update 2013, type 3). Mean serum creatinine was 0.8 mg/dL at 9 mo follow-up. The waiting time in KPD was short as compared to deceased donor KT.

CONCLUSION

We report first non-simultaneous, single center, 6-way kidney exchange transplantation from India. Our experience will encourage other centers in India to undertake this practice.