Clinical Response and Safety of Angiotensin Receptor and Neprilysin Inhibitor Combination in Advanced Chronic Kidney Disease and Heart Failure with Reduced Ejection Fraction.

BACKGROUND: Though the combination of an angiotensin receptor blocker (ARB) and a neprilysin inhibitor (ARNi) has been shown to be useful in heart failure with reduced ejection fraction (HFrEF), its use has mostly been restricted to chronic kidney disease (CKD) patients with an estimated glomerular filtration rate (eGFR) >30 mL/minute/1.73 m2 . We studied the role of ARNi in advanced CKD. MATERIALS AND METHODS: Patients with HFrEF and advanced CKD with an eGFR of <30 mL/ minute/1.73 m2 were given ARNi (sacubitril with valsartan) and prospectively studied for changes in hospitalization rate for HF, clinical symptoms, levels of N-terminal prohormone of brain natriuretic peptide (NT-proBNP), eGFR, and potassium. RESULTS: Of 34 patients who received ARNi, five were excluded due to hyperkalemia and three due to a decrease in eGFR >30% occurring within 1 month. The remaining 26 patients included 17 with diabetes mellitus (DM) and 23 with underlying coronary artery disease. A total of eight patients had stage 4 and 18 stage 5 CKDs, amongst which eight required hemodialysis. Following ARNi, there was a significant decrease in the need for hospitalization for breathlessness (2.04 ± 1.03-0.23 ± 0.51; p < 0,05), New York Heart Association (NYHA) and Kansas City Cardiomyopathy Questionnaire (KCCQ) scores (3.77 ± 0.43-2.19 ± 0.56 and 28.58 ± 9.04-64.81 ± 14.3, respectively, p < 0.001) and NT-pro-BNP levels (24761 ± 12157.51-20149.92 ± 13555.269, p < 0.05) without significant change in eGFR after 6 months. There were no significant differences in the need for hospitalization, changes in NT proBNP levels and eGFR between stages 4 and 5. CONCLUSION: Neprilysin inhibitor (ARNi) is effective and can be used with care even in patients with CKD stages 4 and 5 having HFrEF with monitoring of eGFR and potassium.

Pharmacogenetics Based Dose Prediction Model for Initial Tacrolimus Dosing in Renal Transplant Recipients.

Tacrolimus, an immunosuppressant used in solid organ transplantation, has a narrow therapeutic index and exhibits inter-individual pharmacokinetic variability. Achieving and maintaining a therapeutic level of the drug by giving appropriate doses is crucial for successful immunosuppression, especially during the initial post-transplant period. We studied the effect of CYP3A5, CYP3A4, and ABCB1 gene polymorphisms on tacrolimus trough concentrations in South Indian renal transplant recipients from Kerala to formulate a genotype-based dosing equation to calculate the required starting daily dose of tacrolimus to be given to each patient to attain optimal initial post-transplant period drug level. We also investigated the effect of these genes on drug-induced adverse effects and rejection episodes and looked into the global distribution of allele frequencies of these polymorphisms. One hundred forty-five renal transplant recipients on a triple immunosuppressive regimen of tacrolimus, mycophenolate mofetil, and steroid were included in this study. Clinical data including tacrolimus daily doses, trough levels (C0) and dose-adjusted tacrolimus trough concentration (C0/D) in blood at three time points (day 6, 6 months, and 1-year post-transplantation), adverse drug effects, rejection episodes, serum creatinine levels, etc., were recorded. The patients were genotyped for CYP3A5*3, CYP3A4*1B, CYP3A4*1G, ABCB1 G2677T, and ABCB1 C3435T polymorphisms by the PCR-RFLP method. We found that CYP3A5*3 polymorphism was the single most strongly associated factor determining the tacrolimus C0/D in blood at all three time points (p < 0.001). Using multiple linear regression, we formulated a simple and easy to compute equation that will help the clinician calculate the starting tacrolimus dose per kg body weight to be administered to a patient to attain optimal initial post-transplant period tacrolimus level. CYP3A5 expressors had an increased chance of rejection than non-expressors (p = 0.028), while non-expressors had an increased risk for new-onset diabetes mellitus after transplantation (NODAT) than expressors (p = 0.018). Genotype-guided initial tacrolimus dosing would help transplant recipients achieve optimal initial post-transplant period tacrolimus levels and thus prevent the adverse effects due to overdose and rejection due to inadequate dose. We observed inter-population differences in allele frequencies of drug metabolizer and transporter genes, emphasizing the importance of formulating population-specific dose prediction models to draw results of clinical relevance.

Clinical Response and Pattern of B cell Suppression with Single Low Dose Rituximab in Nephrology.

Background: There is no consensus regarding dose and frequency of rituximab in nephrology with extrapolation of doses used in treating lymphoproliferative disorders. There are no guidelines on targeting initial and subsequent doses on the basis of CD19+ B cells. Methods: Initially, 100 mg rituximab was given to 42 adults with steroid-dependent nephrotic syndrome (SDNS) and frequently relapsing nephrotic syndrome (FRNS), idiopathic membranous nephropathy (MN), and high-immunologic-risk kidney transplantation. Absolute and percentage levels of CD19 B cells and clinical status were assessed at baseline, days 30, 90, and 180, and at 1 year. Subsequent doses of rituximab were on the basis of CD19 B cell reconstitution and clinical response. Results: CD19 B cell percentage decreased from 16.3 ± 7.6 to 0.3 ± 0.3 (P≤0.001), 1.9 ± 1.7 (P≤0.001), and 4.0 ± 4.5 (P=0.005) by 30, 90, and 180 days, respectively. Suppression of CD19 B cell count below 1% at days 30, 90, and 180 was seen in 40 of 42 (95.2%), 18 of 42 (42.9%), and 7 of 42 (16.7%) patients, respectively. Of 30 with SDNS and FRNS followed up for 1 year, 29 (96.7%) went into remission at day 30. Remission was sustained in 23 (76.6%) at day 180 and 21 (70%) at 1 year. There was a significant decrease (P<0.001) in the dose of steroids needed to maintain remission at 180 days after rituximab (0.27 ± 0.02 mg/kg to 0.02 ± 0.00 mg/kg). CD19 B cell percentage at 90 days correlated with relapse (P=0.001; odds ratio 1.42; 95% confidence interval, 1.25 to 2.57). Eighteen (60%) required an additional dose. Of five with MN, four achieved remission by 6 months, which was sustained in three by 1 year. Of the seven kidney transplant recipients, two had antibody-mediated rejections, although CD19 B cells were suppressed even at 1 year. Conclusions: Low-dose rituximab induces sustained depletion of CD19 B cells for up to 90 days. Its role in preventing relapses in SDNS, FRNS, MN, and rejection needs further study.

Paying for Hemodialysis in Kerala, India: A Description of Household Financial Hardship in the Context of Medical Subsidy.

INTRODUCTION: Many low- and middle-income countries are implementing strategies to increase dialysis availability as growing numbers of people reach end-stage renal disease. Despite efforts to subsidize care, the economic sustainability of chronic dialysis in these settings remains uncertain. We evaluated the association of medical subsidy with household financial hardship related to hemodialysis in Kerala, India, a state with high penetrance of procedure-based subsidies for patients on dialysis. METHODS: Patients on maintenance hemodialysis at 15 facilities in Kerala were administered a questionnaire that ascertained demographics, dialysis details, and household finances. We estimated direct and indirect costs of hemodialysis, and described the use of medical subsidy. We evaluated whether presence of subsidy (private, charity, or government-sponsored) was associated with lower catastrophic health expenditure (defined as ≥40% of nonsubsistence expenditure spent on dialysis) or distress financing. RESULTS: Of the 835 patients surveyed, 759 (91%) reported their households experienced catastrophic health expenditure, and 644 (77%) engaged in distress financing. Median dialysis-related expenditure was 80% (25th-75th percentile: 60%-90%) of household nonsubsistence expenditure. Government subsidies were used by 238 (29%) of households, 139 (58%) of which were in the lowest income category. Catastrophic health expenditure was present in 215 (90%) of households receiving government subsidy and 332 (93%) without subsidy. CONCLUSIONS: Provision of medical subsidy in Kerala, India was not associated with lower rates of household financial hardship related to long-term hemodialysis therapy. Transparent counseling on impending costs and innovative strategies to mitigate household financial distress are necessary for persons with end-stage renal disease in resource-limited settings.

Clinical course of dengue fever and its impact on renal function in renal transplant recipients and patients with chronic kidney disease.

AIM: Dengue fever is a mosquito-borne viral disease endemic in many tropical and sub-tropical countries. There are only limited data in the literature about dengue fever in renal transplant recipients and patients with chronic kidney disease. This study compares the clinical course of dengue fever and its impact on renal function in renal transplant recipients, patients with chronic kidney disease and patients with normal baseline renal function. METHODS: An observational study was conducted from 1 May to 31 July 2017, at a tertiary care centre of South India. A major epidemic of dengue had occurred during the study period. Twelve renal transplant recipients, 22 patients with CKD and 58 patients with normal baseline renal function (control group) admitted with dengue fever were prospectively studied. RESULTS: Nadir WBC count was lowest in renal transplant recipients (2575 ± 1187/mm3 ), [P < 0.001]. Renal transplant recipients took more time for normalization of platelet count (6 ± 4.5 days), [P < 0.001]. All 22 patients with CKD and 11 of 12 renal transplant recipients had worsening of renal function whereas only 17 of 58 patients in the control group had worsening [P < 0.001]. Sixteen patients with CKD, one renal transplant recipient and none among the control group required haemodialysis [P < 0.001]. Dialysis requiring patients had more haemoconcentration (52.5 ± 19.9% increase in haemoglobin), [P < 0.001]. Seven patients with CKD were dialysis dependent at the end of 2 weeks. CONCLUSION: Clinical features of dengue fever were different in renal transplant recipients and patients with CKD. Severe worsening of renal function was common in CKD patients. Worsening of renal function in renal transplant recipients was less severe and transient.

Lactate levels and risk of lactic acidosis with metformin in diabetic kidney disease patients.

Metformin as an oral antidiabetic drug (OAD) is not recommended in renal failure due to the presumed risk of lactic acidosis though it has advantages in cardiovascular protection with a low risk of hypoglycemia. Few studies have measured lactic acid blood levels in patients with diabetic kidney disease on metformin and demonstrated lactic acidosis. The aim of our study is to see if patients with diabetic kidney disease are at risk of elevated lactate blood levels and lactic acidosis. Lactate levels and blood pH were estimated in patients with type 2 diabetes mellitus receiving metformin in different stages of chronic kidney disease (CKD) and were compared with a similar group not receiving metformin. Patients with diabetic kidney disease, with estimated glomerular filtration rate <60 mL/min who were previously receiving metformin started in centers elsewhere and referred here were studied and compared with a similar group taking other OADs or insulin. Independent sample t-test or ANOVA were used to compare quantitative variables between groups. Pearson correlation was used to analyze association between quantitative variables and linear regression analysis and was employed to note the relationship between quantitative variables. Of 57 patients who received a mean dose of 1.134 grams of metformin, 33 (55.9%) were in stage 3, 16 (28.1%) in stage 4, and 8 (14%) in stage 5 CKD. Mean serum pH (P = 0.572), bicarbonate (P = 0.978), and plasma lactate (P = 0.449) levels in those taking and not taking metformin were comparable. There was no difference in the plasma lactate levels in different stages of CKD in the metformin group (P = 0.498) although there was significant correlation with metformin dose (P <0.05). Blood lactate levels were not elevated in patients with diabetic kidney disease at a daily dose of metformin <1 g.

Polymorphism of the CYP3A5 gene and its effect on tacrolimus blood level.

OBJECTIVES: Tacrolimus is the cornerstone for immunosuppression in renal transplant and is metabolized by the cytochrome P 450 3A (CYP3A) subfamily of enzymes in the liver and small intestine. A polymorphism in intron 3 of the CYP3A5 gene affects the expression of this enzyme and tacrolimus trough blood levels. The purpose of this study was to identify the proportion of CYP3A5 gene polymorphisms in South Indian renal transplant patients and determine the effect of CYP3A5 gene polymorphisms on tacrolimus trough blood levels in patients with and without CYP3A5 expression. MATERIALS AND METHODS: We included 25 adult patients who underwent renal transplant at Government Medical College, Trivandrum. All patients received tacrolimus (dose, 0.1 mg/kg/body weight, in 2 divided doses). Tacrolimus trough blood levels were determined on postoperative day 6. The CYP3A5 genotype analysis was performed by polymerase chain reaction amplification of target and detection by restriction fragment length polymorphism analysis. RESULTS: The CYP3A5*1/*1 genotype was detected in 5 recipients (20%), *1/*3 genotype in 5 recipients (20%), and *3/*3 genotypes in 15 recipients (60%) of the total 25 graft recipients. Mean tacrolimus level in the CYP3A5*1/*1 group was 5.154 ng/mL (range, 4.42 to 6.5 ng/mL), CYP3A5*1/*3 group was 5.348 ng/mL (range, 3.1 to 9.87 ng/mL), and CYP3A5*3/*3 group was 9.483 ng/mL (range, 4.5 to14.1 ng/mL). Acute rejection episodes were significantly more frequent for CYP3A5*1/*1 homozygous patients (40%) than patients with CYP3A5*1/*3 (20%) or CYP3A5*3/*3 (13%) genotypes. CONCLUSIONS: Most patients carried the mutant allele CYP3A5*3 (A6986G). Tacrolimus drug level correlated well with presence or absence of CYP3A5 polymorphisms. Acute rejection episodes were more frequent in expressors, and they may require higher doses of tacrolimus. Similarly, tacrolimus nephrotoxicity was more frequent in non-expressors. Therefore, CYP3A5 polymorphism analysis before renal transplant may help determine the optimal dose of tacrolimus in this population and prevent acute rejection episodes or tacrolimus toxicity.

Acute Oxalate Nephropathy following Ingestion of Averrhoa bilimbi Juice.

Plant toxins are known to cause acute kidney injury in tropical countries. We report two cases of acute kidney injury with tubular oxalate deposition following ingestion of Averrhoa bilimbi fruit juice. Both patients had complete renal recovery though one required dialytic support.

A case of Goodpasture's syndrome complicating pregnancy with dialysis requiring renal failure responding to plasmapheresis and termination of pregnancy.

Goodpasture's syndrome complicating pregnancy is extremely rare and dialysis requiring anti GBM disease with renal recovery is uncommon. We report a case of a 23-year-old primi gravida who presented with Goodpasture's syndrome during thirteenth week of pregnancy. She was initiated on steroids and cytotoxic drugs along with intensive plasma exchange and alternate day hemodialysis. Her pregnancy was terminated at 15 weeks. Patient improved dramatically with treatment, her renal functions normalized and her Anti GBM antibody titer became negative.