ABO-Incompatible Kidney Transplantation in India: A Single-Center Experience of First Hundred Cases.

Aim: ABO-incompatible (ABOi) kidney transplantation overcomes immunological barrier of blood group incompatibility. There have been very few published experiences of ABOi kidney transplantation from India. We present our single-center experience of the first hundred ABOi kidney transplants. Material and Methods: This is a single-center retrospective study of consecutive first hundred ABOi kidney transplant with at least 6 months of follow-up. Results: During the study period (2011-2020), a total of 121 ABOi kidney transplants were performed. Of these, first hundred patients were analyzed. Median follow-up duration was 33 (10-101) months. Mean recipient and donor age were 41.5 ± 13 and 47.68 ± 11.25 years, respectively. Mean HLA mismatch was 4 ± 1.5. Median baseline anti-blood group antibody titer was 128 (2-1024). Most common recipient blood group was O. Patient and death censored graft survival was 93% and 94%, respectively, at median follow-up of 33 months. Biopsy-proven acute rejection (BPAR) rate was 17% with acute antibody-mediated rejection being 3%. Rate of infection was 37%, most common being urinary tract infection. Conclusion: ABOi kidney transplant patients had acceptable patient and graft survival as well as BPAR rates. With current preconditioning protocol, infection rate was high.

Grafalon® vs. Thymoglobulin® as an Induction Agent in Renal Transplantation - A Retrospective Study.

INTRODUCTION: Antihuman thymocyte immunoglobulin, used as an induction agent in renal transplantation, is of two types - thymoglobulin and grafalon (formerly ATG-Fresenius). In this study, we compared outcomes with these two agents. METHODS: This was a single-center retrospective study of patients transplanted from January 2017 to October 2019, who received either grafalon or thymoglobulin induction. Grafalon or thymoglobulin was given at 6 and 3 mg/kg, respectively, followed by standard triple immunosuppression of tacrolimus, MMF, and prednisolone. RESULTS: Median follow up was 22 (3-36) months. Thymoglobulin was given to 255 patients, whereas 78 patients received grafalon. Baseline demographics were similar between the two groups although significantly more patients in the grafalon group received ABO incompatible transplant (15% vs. 4.3%; P = 0.002). Patient survival was similar between the two groups (99% in grafalon vs. 98.8% in thymoglobulin; P = 1.0). Death censored graft survival was also similar (99% in grafalon vs. 100% in thymoglobulin; P = 0.23). Biopsy proven acute rejection (BPAR) was significantly higher in the grafalon group (12.8% vs. 5.1%, P = 0.04). The significance persisted after multivariable regression analysis (P = 0.02). Other outcomes such as infection rate and estimated glomerular filtration rate on last follow up were comparable between the two groups. CONCLUSIONS: Grafalon (6 mg/kg dose) when used as an induction agent was associated with significantly higher rate of BPARs as compared to thymoglobulin (3 mg/kg dose) although with comparable short-term patient and death censored graft survival, graft function, and infection rates.

Prevention and Therapy of AKI in Asia: A Big Challenge.

Asia is the largest and most populous continent and has huge differences in socioeconomic status, development, and health care between the different countries and regions within each country. This manifests in the varied causes of acute kidney injury (AKI), particularly higher rates of community-acquired AKI and in the differential access to health care for the population. Because of resource limitations, prevention and treatment of AKI is a difficult challenge. This review highlights the differences in AKI in Asia compared with the developed world and discusses prevention and treatment of AKI within the context of resource limitations.

De novo NAD+ biosynthetic impairment in acute kidney injury in humans.

Nicotinamide adenine dinucleotide (NAD+) extends longevity in experimental organisms, raising interest in its impact on human health. De novo NAD+ biosynthesis from tryptophan is evolutionarily conserved yet considered supplanted among higher species by biosynthesis from nicotinamide (NAM). Here we show that a bottleneck enzyme in de novo biosynthesis, quinolinate phosphoribosyltransferase (QPRT), defends renal NAD+ and mediates resistance to acute kidney injury (AKI). Following murine AKI, renal NAD+ fell, quinolinate rose, and QPRT declined. QPRT+/- mice exhibited higher quinolinate, lower NAD+, and higher AKI susceptibility. Metabolomics suggested an elevated urinary quinolinate/tryptophan ratio (uQ/T) as an indicator of reduced QPRT. Elevated uQ/T predicted AKI and other adverse outcomes in critically ill patients. A phase 1 placebo-controlled study of oral NAM demonstrated a dose-related increase in circulating NAD+ metabolites. NAM was well tolerated and was associated with less AKI. Therefore, impaired NAD+ biosynthesis may be a feature of high-risk hospitalizations for which NAD+ augmentation could be beneficial.

Reimbursement for living kidney donor follow-up care: how often does donor insurance pay?

BACKGROUND: Currently, many transplantation centers do not follow former living kidney donors on a long-term basis. Several potential barriers have been identified to provide this follow-up of former living kidney donors, including concerns that donor insurance will not reimburse transplantation centers or primary care physicians for this care. Here, we report the rates at which different insurance companies reimbursed our transplantation center for follow-up visits of living donors. METHODS: We collected data on all yearly follow-up visits of living donors billed from January 1, 2007, to December 31, 2010, representing 82 different donors. Concurrent visits of their recipients were available for 47 recipients and were used as a control group. RESULTS: We find that most bills for follow-up visits of living kidney donors were paid by insurance companies, at a rate similar to the reimbursement for recipient follow-up care. CONCLUSIONS: Our findings suggest that, for former donors with insurance, inadequate reimbursement should not be a barrier in providing follow-up care.

Pre-emptive kidney transplantation to improve survival in patients with type 1 diabetes and imminent risk of ESRD.

Despite significant improvements in the treatment of diabetic nephropathy over the past 20 years, patients with type 1 diabetes are at high risk of developing end-stage renal disease and high mortality once end-stage renal disease develops. Type 1 diabetic patients treated with predialysis (pre-emptive) transplantation have a lower death rate than type 1 diabetic patients treated with dialysis. Living donor kidney transplantation is possible before starting dialysis and is associated with better kidney and patient outcomes as compared with transplantation while on dialysis. In addition, a variety of potential donors can be used, not just young, well-matched family members. Through paired kidney donation, blood group ABO-incompatible transplants and transplants across the barrier of anti-human leukocyte antigen antibodies, diabetic patients can receive living donor kidney transplants even if their intended donor is not a good match for them. Despite these expanded options making living donation possible, only a minority of type 1 diabetic patients receive a pre-emptive kidney transplant. Multiple barriers remain that prevent type 1 diabetic patients from enjoying the reduced risk of death afforded by a pre-emptive kidney transplant, including lack of knowledge by primary care physicians, endocrinologists, and nephrologists; late referral for transplantation; patient and family misconceptions about timing of transplantation; and who can be a donor. The vast majority of type 1 diabetic patients are listed for kidney transplantation after the initiation of dialysis. Of these patients, thousands subsequently receive a live donor kidney transplant. We believe that the appropriate agencies and societies should address the barriers to pre-emptive kidney transplantation through nationwide educational initiatives and study the causes of failure to be transplanted before dialysis initiation.

Immunotherapy in renal diseases.

Immunotherapy has been used for the treatment of renal diseases for a long time, and there has been significant progress in such treatment. This review focuses on the use of immunotherapy for the treatment of glomerular diseases. The use of immunosuppression in the treatment of minimal change disease, membranous nephropathy, primary focal segmental glomerulosclerosis, lupus nephritis, immunoglobulin-A nephropathy, antineutrophil cytoplasmic antibody-associated disease, and anti-glomerular basement membrane disease is discussed.

The living kidney donor evaluation: focus on renal issues.

Living kidney donor evaluations and follow-up have previously been addressed mostly by transplant physicians and surgeons. However, this area is significantly informed by basic principles of renal physiology and is of increasing clinical interest to general nephrologists. The general nephrology community is increasingly involved in evaluating the suitability of potential donors and in following them after donation when questions are raised about low GFR, hypertension, and other renal concerns. This article focuses on some of the most central and common issues that arise in evaluating potential donors and attempts to provide guidance on the basis of our review of the living donor literature, extrapolations from the general nephrology literature, and our own clinical experience.

PGC-1α promotes recovery after acute kidney injury during systemic inflammation in mice.

Sepsis-associated acute kidney injury (AKI) is a common and morbid condition that is distinguishable from typical ischemic renal injury by its paucity of tubular cell death. The mechanisms underlying renal dysfunction in individuals with sepsis-associated AKI are therefore less clear. Here we have shown that endotoxemia reduces oxygen delivery to the kidney, without changing tissue oxygen levels, suggesting reduced oxygen consumption by the kidney cells. Tubular mitochondria were swollen, and their function was impaired. Expression profiling showed that oxidative phosphorylation genes were selectively suppressed during sepsis-associated AKI and reactivated when global function was normalized. PPARγ coactivator-1α (PGC-1α), a major regulator of mitochondrial biogenesis and metabolism, not only followed this pattern but was proportionally suppressed with the degree of renal impairment. Furthermore, tubular cells had reduced PGC-1α expression and oxygen consumption in response to TNF-α; however, excess PGC-1α reversed the latter effect. Both global and tubule-specific PGC-1α-knockout mice had normal basal renal function but suffered persistent injury following endotoxemia. Our results demonstrate what we believe to be a novel mechanism for sepsis-associated AKI and suggest that PGC-1α induction may be necessary for recovery from this disorder, identifying a potential new target for future therapeutic studies.

Disparate IL-1beta and iNOS gene expression in the aorta and pulmonary artery after endotoxemia.

BACKGROUND: Endotoxemia causes paradoxical effects on the systemic and pulmonary vasculature, resulting in systemic hypotension and increased pulmonary artery pressure. The local production of inflammatory mediators may have important effects on vascular tissue function. The purpose of this study was to delineate differences in function and the expression of tissue cytokine genes in the aorta and pulmonary artery after endotoxemia. METHODS: Thoracic aorta and pulmonary artery branches were isolated from adult Sprague- Dawley rats (n = 4-6/group) 6 h after intraperitoneal injection of lipopolysaccharide (Salmonella typhimurium, 20 mg/kg) or vehicle (1.0 mL of saline). Arteries were suspended in perfused organ baths for measurement of isometric force transduction, and dose-response curves to phenylephrine (0.01-10 micromol/L), acetylcholine (0.01-10 micromol/L), and sodium nitroprusside (0.001-10 micromol/L) were generated. The vascular segments were also assessed for expression of tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta, IL-6, and inducible nitric oxide synthase (iNOS) messenger RNA (mRNA) by semiquantitative reverse transcriptase- polymerase chain reaction. RESULTS: Endotoxemia resulted in decreased contractility of the aorta (508.63 +/- 81.89 mg vs. 2544.16 +/- 142.05 mg in the vehicle group) and pulmonary artery (352.50 +/- 38.11 mg vs. 535.83 +/- 45.51 mg in the vehicle group) and decreased endothelium-dependent pulmonary artery relaxation (52.86 +/- 5.63% vs. 80.58 +/- 6.39% in the vehicle group). Expression of IL-1beta and iNOS mRNA by the pulmonary artery, but not the aorta, increased significantly in the endotoxintreated animals. Interleukin-6 was increased in both the pulmonary artery and the aorta during endotoxemia, whereas TNF concentrations were unchanged. CONCLUSIONS: Endotoxemia may cause aortic hypocontractility and impaired endothelium-dependent pulmonary artery vasorelaxation. Expression of inflammatory genes in vascular tissue may be site-specific and may contribute to the functional derangements associated with sepsis.

Endogenous estrogen mediates a higher threshold for endotoxin-induced myocardial protection in females.

Myocardial endotoxin tolerance may be induced in both males and females; however, it remains unknown whether there are mechanistic and threshold differences between the sexes. We hypothesized that endogenous estrogen mediates a higher threshold for endotoxin (ETX)-induced protection in females. Adult proestrus and ovariectomized (OVX) female rats were preconditioned (PC) with intraperitoneal injections of 125 (PC+125) or 500 (PC+500) microg/kg Salmonella typhimurium LPS (ETX) or normal saline (PC-). Twenty-four hours later, injury dose ETX (500 microg/kg) was injected. After 6 h, myocardial function was measured via Langendorff. p38 MAPK and JNK activation and TNF-alpha, IL-1, and IL-6 expression were evaluated. ETX injury significantly decreased left ventricular developed pressure in PC- groups vs. controls. PC+500 regimen protected against ETX injury, resulting in normal cardiac function. PC+125 regimen protected OVX but not proestrus females, which had diminished myocardial function. Activated JNK and TNF-alpha increased in PC- but were diminished in PC+500 animals. Importantly, activated JNK and TNF increased in PC+125 proestrus females, whereas PC+125 OVX females displayed decreases in these molecules. There were no differences in p38 MAPK activation or expression of IL-1 or IL-6. These results demonstrate that proestrus females require a higher stimulus (PC+500) to achieve myocardial protection against ETX injury. Removal of endogenous estrogen (OVX) lowered the preconditioning threshold (PC+125), resulting in protection after lesser injury. Additionally, myocardial JNK and TNF expression was decreased in OVX PC+125 females, which correlated with myocardial function differences. Therefore, we conclude that endogenous estrogen mediates a higher threshold for ETX tolerance in female myocardium.

Zaprinast attenuates hypoxic pulmonary artery injury and causes less aortic relaxation than milrinone.

Hypoxic pulmonary vasoconstriction is a challenging clinical problem with limited therapeutic options. Milrinone, a phosphodiesterase (PDE)-3 inhibitor, is frequently used to treat perioperative pulmonary hypertension. However, recent evidence suggests that the PDE-5 isoform may be more specific for lung tissue. We hypothesized that the PDE-5 inhibitor zaprinast has greater efficacy for pulmonary vasorelaxation, attenuation of hypoxic pulmonary vasoconstriction, and inhibition of hypoxia-induced pulmonary artery cytokine expression when compared with milrinone. To study this, isolated rat pulmonary artery and thoracic aorta rings suspended in physiologic organ baths for measurement of isometric force transduction were treated with vehicle (dimethyl sulfoxide), milrinone, or zaprinast to assess pulmonary artery relaxation, thoracic aorta relaxation, inhibition of hypoxic (pO2 = 30-35 mmHg) pulmonary vasoconstriction, and hypoxia-induced pulmonary artery TNF-alpha and IL-1beta expression (reverse transcriptase-PCR). Milrinone and zaprinast resulted in dose-dependent pulmonary artery and aortic relaxation, but zaprinast caused significantly less aortic relaxation compared with milrinone (50.12% +/- 3.36% versus 91.03% +/- 2.97%, P < 0.001). Zaprinast, but not milrinone, significantly inhibited hypoxic pulmonary vasoconstriction (zaprinast, 58.42% +/- 5.37%; milrinone, 77.65% +/- 4.42% versus vehicle: 74.42% +/- 7.54%). Hypoxia-induced upregulation of TNF-alpha and IL-1beta mRNA in pulmonary artery was decreased by zaprinast, but not milrinone, pretreatment. These results suggest that zaprinast, but not milrinone, preferentially vasodilates pulmonary artery over aorta, attenuates hypoxic pulmonary vasoconstriction, and inhibits hypoxia-induced pulmonary artery TNF-alpha and IL-1beta expression. Therefore, PDE-5 inhibition may be advantageous in the treatment of pulmonary hypertension.

Sexual dimorphism in myocardial tumor necrosis factor-alpha and cardiac function during endotoxin tolerance.

BACKGROUND: Preconditioning is injury-induced protection against subsequent injury and may be induced by a variety of stimuli. Both males and females may be preconditioned; however, if females are relatively protected against the initial insult, is their preconditioning threshold higher? We hypothesized that preconditioning injury threshold differences may exist between genders, which may be associated with differences in myocardial inflammatory monokine production. METHODS: Male and female Sprague-Dawley rats (n=3-5/group) were given intraperitoneal injections of 125 or 500 microg/kg Salmonella typhimurium lipopolysaccharide (ETX) or 0.4 mL normal saline (NS; 154 mmol/L NaCl). After 24 hours, another injection of 500 microg/kg ETX (injury dose) or NS was given, and the animals were incubated an additional 1 or 6 hours. The rats were anesthetized and myocardial function evaluated via the Langendorff perfusion model. Tumor necrosis factor-alpha (TNF-alpha), interleukin-(IL)-1beta, and IL-6 were measured in 1-hour animals via an enzyme-linked immunosorbent assay. Nonpreconditioned rats (PC-) received NS followed by ETX. Preconditioned rats received either 125 microg/kg ETX (PC+125) or 500 microg/kg ETX (PC+500) followed by injury dose ETX. RESULTS: PC+125 and PC+500 males, as well as PC+500 females, were preconditioned and retained cardiac function similar to shams. PC+125 females were not preconditioned with this stimulus and had a decrease in cardiac function similar to PC- rats. Furthermore, PC+125 and PC+500 males, and PC+500 females had decreased release of TNF-alpha after preconditioning, while PC- animals and PC+125 females did not. CONCLUSIONS: Males and females can be preconditioned by endotoxin; however the preconditioning threshold is higher in females than males.

Aprotinin improves kidney function and decreases tubular cell apoptosis and proapoptotic signaling after renal ischemia-reperfusion.

OBJECTIVE: The purpose of the study was to determine the effects of aprotinin on (1) renal function, (2) apoptosis and apoptotic signaling, and (3) the inflammatory response of the kidney after ischemia-reperfusion injury. METHODS: Male rats underwent a sham procedure or left renal ischemia for 1 hour. Rats were divided into three groups and received no reperfusion, reperfusion for 1 hour, or reperfusion for 24 hours. The animals undergoing ischemia received saline solution alone or aprotinin (60,000 kIU/kg). At the end of the experiment, a sample for serum creatinine was taken and the left kidney was harvested. The kidney was analyzed for expression of tumor necrosis factor alpha, interleukin 1beta, and interleukin 6 (enzyme-linked immunosorbent assay and reverse transcriptase-polymerase chain reaction) and activation of p38 mitogen-activated protein kinase, caspase 3, and caspase 8 (Western blot). The kidney was assessed for apoptosis with enzyme-linked immunosorbent assay and by terminal deoxynucleotidyl transferase biotin-deoxyuridine triphosphate nick-end labeling staining of tissue slides. RESULTS: Aprotinin significantly decreased the rise in serum creatinine and apoptosis caused by ischemia-reperfusion. Aprotinin significantly reduced interleukin 1 and 6 messenger RNA production and showed a trend toward reducing tumor necrosis factor messenger RNA production after ischemia. Aprotinin also significantly reduced caspase 8 activation and showed a trend toward decreasing p38 mitogen-activated protein kinase activation after 1 hour of reperfusion. CONCLUSION: These results suggest that aprotinin provides protection from renal ischemia-reperfusion injury. They also suggest that aprotinin may do so by affecting apoptotic signaling and inflammatory cytokine production. Aprotinin is a potential therapeutic measure in clinical situations where renal ischemia-reperfusion injury can be anticipated, provided adequate heparinization is possible.

Endothelium-dependent pulmonary artery vasorelaxation is dysfunctional in males but not females after acute lung injury.

BACKGROUND: Mortality after acute respiratory distress syndrome is higher in males than in females. Gender differences in pulmonary vascular reactivity and local inflammatory response may explain this disparity. We hypothesized that endothelium-dependent pulmonary vasorelaxation is impaired in males and that this effect is related to differences in local inflammatory cytokine expression from the pulmonary vasculature. METHODS: Pulmonary artery (PA) rings (n = 12-16 per group) were isolated from adult male and female Sprague-Dawley rats treated with endotoxin (Salmonella typhimurium lipopolysaccharide, 20 mg/kg IP) or vehicle (0.9% normal saline), and connected to force transducers for measurement of isometric force displacement. Dose-response curves (0.01-10 micromol/L) to the endothelium-dependent vasodilator acetylcholine and the endothelium-independent vasodilator sodium nitroprusside were generated. PA rings were also evaluated for inducible nitric oxide synthase, tumor necrosis factor-alpha, and interleukin 1beta messenger RNA (mRNA) by reverse transcriptase-polymerase chain reaction. RESULTS: Endotoxin had no effect on the maximum PA contraction in males (564.4 +/- 37.37 mg vs 633.3 +/- 54.67 mg vehicle) or females (446.3 +/- 20.00 mg vs 444.2 +/- 33.02 mg vehicle), but endothelium-dependent vasodilation was significantly decreased in males (47.49 +/- 5.63% vs 77.61 +/- 9.41% vehicle). Endothelium-independent vasodilation remained intact during endotoxemia. Endotoxin increased the PA expression of inducible nitric oxide synthase mRNA, but there was no gender difference. There was no change in expression of PA tumor necrosis factor, whereas endotoxemic males, but not females, had increased interleukin 1beta mRNA, compared with vehicle. CONCLUSIONS: These results suggest that sepsis-induced vascular dysfunction differs between males and females, and, therefore, treatment of acute lung injury may require gender-specific therapies.

Cellular and molecular mechanisms of sex differences in renal ischemia-reperfusion injury.

Renal ischemia-reperfusion (I/R) is an important etiopathological mechanism of acute renal failure (ARF). Despite improvements in the treatment of ARF, it is associated with significant morbidity and mortality. I/R injury also occurs during renal transplantation and leads to reduced allograft survival. Sex differences have been found in I/R injury in many different organs including the kidney. Women have half the mortality of men in ARF. In animal models also, females are protected against renal I/R injury. The mechanisms by which sex affects the outcome to renal I/R injury are being actively investigated. This review will examine the evidence for gender differences in renal I/R injury and discuss the probable mechanisms by which sex affects the renal response to I/R injury.

Preconditioning: gender effects.

Preconditioning is injury induced protection from subsequent injury. During preconditioning protective cellular responses to injury are up regulated resulting in acute and delayed defense against further damage. Several studies indicate that females experience a protective advantage after acute insult compared to males. Despite evidence of gender differences in acute injury, relatively few studies have evaluated whether there are sex differences in preconditioning. Variations in patients' pre-morbid preconditioning status may explain outcome variations that are not apparent in small animal studies. This review discusses the differences in response to acute injury experienced by males and females, the basic mechanisms of preconditioning, and the sex differences in the mechanisms of preconditioning.

Is the preconditioning threshold different in females?

BACKGROUND: Preconditioning is injury induced protection against subsequent insult. Studies have shown that both males and females may be preconditioned. Females appear to have an innate cardioprotection, therefore, we hypothesized that the preconditioning threshold may differ between males and females. MATERIALS AND METHODS: Male and female rats were divided into five groups (n=4-9). Animals were given an intraperitoneal (i.p.) injection of 125, 250, or 500 micrograms/kilogram Salmonella typhimurium lipopolysaccharide (ETX) or 0.4-ml normal saline (NS). After 24-h incubation another i.p. injection of either 500 micrograms/kilogram ETX (injury dose) or NS was given and the animals incubated an additional 6 h. Shams received two injections of NS. Non-preconditioned rats (PC-) received NS followed by ETX. Preconditioned rats had i.p. injections of 125 mug/kg ETX (PC +125), 250 microg/kg ETX (PC +250), or 500 microg/kg ETX (PC +500) followed by the injury dose ETX. The rats were then anesthetized and myocardial function evaluated with the Langendorff perfusion model. RESULTS: PC +500 females were preconditioned and were able to maintain cardiac function similar to shams. Conversely, PC +125 females were not preconditioned with this stimulus and had a significant decrease in cardiac function similar to PC- rats. Male PC +500 and PC +125 rats, however, retained cardiac function comparable to shams, while PC- males showed a significant decrement. CONCLUSIONS: Males and females may each be preconditioned by endotoxin; however, the preconditioning threshold is higher in females than males.