Levofloxacin based non-rifampicin anti-tuberculous therapy: An effective alternative in renal transplant recipients in resource limited setting.

INTRODUCTION: Rifampicin is one of the most effective components of anti-tuberculous therapy (ATT). Since rifampicin is a hepatic enzyme (CYP3A4) inducer, in a post-renal transplant recipient, the dose of calcineurin inhibitors needs to be up-regulated and frequently monitored. In resource-limited (low- and lower-middle-income countries) setting this is not always feasible. Therefore, we evaluated a non-rifampicin-based ATT using levofloxacin in kidney transplant recipients. METHODS: We retrospectively studied the medical records of renal transplant recipients diagnosed with tuberculosis in our institute between 2014 and 2017. After a brief discussion with patients regarding the nature and course of ATT, those who opted for a non-rifampicin based therapy due to financial constraints were included in the study and followed for a minimum of 6 months period after the completion of ATT. RESULTS: Out of the 550 renal transplant recipients, 67 (12.2%) developed tuberculosis after a median period of 24 (1-228) months following transplantation, of them, 64 patients opted for non-rifampicin-based ATT. The mean age was 37.6 years. Only 25% were given anti-thymocyte globulin based induction, while the majority (56; 87.5%) of them were on tacrolimus-based triple-drug maintenance therapy. Extrapulmonary tuberculosis was noted in 33% of cases, while 12 (18.7%) had disseminated disease. The median duration of treatment was 12 months and the cure rate of 93.7% (n = 60) was achieved at the end of therapy. CONCLUSION: Levofloxacin based ATT appears to be a safe and effective alternative of rifampicin in kidney transplant recipients who cannot afford heightened tacrolimus dosage.

Effect of vitamin D supplementation on serum sclerostin levels in chronic kidney disease.

Vitamin D deficiency, cardiovascular disease and abnormal bone mineral metabolism are common in chronic kidney disease (CKD). Abnormal bone mineral metabolism has been linked to vascular calcification in CKD. Sclerostin has emerged as an important messenger in cross talk between bone-vascular axis. We analyzed sclerostin in subjects who participated in the randomized, double blind, placebo controlled trial investigating the effect of cholecalciferol supplementation on vascular function in non-diabetic CKD stage G3-4 and vitamin D ≤ 20 ng/ml [CTRI/2013/05/003648]. Patients were randomized (1:1) to receive either two directly observed oral doses of 300,000 IU of cholecalciferol or matching placebo at baseline and 8 weeks. Of the 120 subjects enrolled, 58 in the cholecalciferol group and 59 in the placebo group completed the study. At baseline, serum levels of sclerostin were similar in both groups (cholecalciferol - median;190pg/ml, IQR;140-260 pg/ml and placebo - median;180 pg/ml, IQR; 140-240 pg/ml, p = 0.67). 16 weeks after cholecalciferol supplementation, there was no change in level of sclerostin (mean change;1.10 pg/ml, 95%CI; -27.34 to 29.34 pg/ml, p = 0.25). However, a significant decrease in sclerostin level was noted in the placebo group (mean change; -31.94 pg/ml, 95%CI; -54.76 to -9.13 pg/ml, p = 0.002). Change (Δ) in sclerostin level at 16 weeks correlated negatively with Δ eGFR (r = -0.20, p = 0.03) and positively with Δuric acid (r = 0.37, p < 0.001) but not with Δ25(OH) D (r = 0.06, p = 0.54), Δ iPTH (r = - 0.03, p = 0.78) ΔFGF23 (r = - 0.08, p = 0.38) and Δ125 (OH)2 D (r = - 0.04, p = 0.65). In conclusion, high dose cholecalciferol supplementation did not change sclerostin levels in non-diabetic stage 3-4 CKD subjects.

Vascular function and cholecalciferol supplementation in CKD: A self-controlled case series.

Vitamin D deficiency is common and associated with mortality in chronic kidney disease (CKD) patients. Cardiovascular disease (CVD) is the commonest cause of mortality in CKD patients. In a randomized, double blind, placebo controlled trial, we have recently reported favorable effects of vitamin D supplementation on vascular & endothelial function and inflammatory biomarkers in vitamin D deficient patients with non-diabetic stage 3-4 CKD (J Am Soc Nephrol 28: 3100-3108, 2017). Subjects in the placebo group who had still not received vitamin D after completion of the trial received two oral doses 300,000 IU of oral cholecalciferol at 8 weeks interval followed by flow mediated dilatation (FMD), pulse wave velocity (PWV), circulating endothelial and inflammatory markers (E-Selectin, vWF, hsCRP and IL-6), 125 (OH)2D, iPTH and iFGF-23 assessment at 16 weeks. 31 subjects completed this phase of the study. Last values recorded in the preceding clinical trial were taken as baseline values. Serum 25(OH)D and 1,25(OH)2D increased and FMD significantly improved after cholecalciferol supplementation [mean change in FMD%: 5.8% (95% CI: 4.0-7.5%, p < 0.001]. Endothelium independent nitroglycerine mediated dilatation, PWV, iPTH, iFGF-23 and IL-6 also showed favorable changes. The data further cement the findings of beneficial effects of correction of vitamin D deficiency on vascular function.

Fibroblast growth factor 23 in untreated nephrotic syndrome.

AIM: Despite its importance in bone and cardiovascular disease in subjects with kidney disease, there are no data on fibroblast growth factor 23 (FGF23) perturbations in nephrotic syndrome. We evaluated FGF23 and markers of mineral bone metabolism in subjects with untreated NS. METHODS: In this cross-sectional study, we measured circulating levels of FGF23, 25-hydroxy vitamin D [25(OH)D], 1,25 di-hydroxy vitamin D [1,25(OH)2 D], serum albumin, serum calcium, phosphorus, creatinine and intact parathyroid hormone (iPTH) in 101 patients with adults onset NS and 40 healthy controls. We examined the correlation between FGF23 and markers of mineral bone metabolism. RESULTS: Compared to healthy controls, subjects with NS showed reduced levels of 25(OH)D (21.76 ± 10.18 vs 35.74 ± 40.27 nmol/L, P = 0.001), 1,25(OH)2 D (median; 37.80 vs 73.13 pmol/L, P = 0.0001) and FGF23 (37.81 ± 20.42 vs 48.20 ± 11.60 pg/mL, P = 0.004) levels. Serum phosphorus levels were marginally, but significantly higher in subjects with nephrotic syndrome compared to healthy controls (P = 0.004). Serum iPTH levels were significantly higher in subjects with NS compared to healthy controls (52.24 ± 39.58 vs 37.90 ± 14.60 pg/mL, P = 0.028). CONCLUSIONS: We conclude that FGF23 is reduced in subjects with NS compared to healthy controls. The reduced levels of Vitamin D, and urinary losses may contribute to lower levels of FGF23 in NS.

The Effect of Vitamin D Supplementation on Bone Metabolic Markers in Chronic Kidney Disease.

Use of active forms of vitamin D is advocated in patients with chronic kidney disease (CKD) for treatment of mineral bone disease because of the presumption that native forms of vitamin D would not undergo significant activation to calcitriol, the most active biological form of vitamin D. We present secondary analysis looking at bone turnover in subjects who completed the randomized, double blind, placebo-controlled trial investigating the effect of cholecalciferol supplementation on vascular function in nondiabetic CKD stage G3-G4 and vitamin D ≤20 ng/mL (Clinical Trials Registry of India: CTRI/2013/05/003648). Patients were randomized (1:1) to receive either two directly observed oral doses of 300,000 IU of cholecalciferol or matching placebo at baseline and 8 weeks. Of the 120 subjects enrolled, 58 in the cholecalciferol group and 59 in the placebo group completed the study. At 16 weeks, the serum 25(OH)D and 1,25(OH)2 D levels increased in the cholecalciferol group but not in the placebo group (between-group difference in mean change: 23.40 ng/mL; 95% CI, 19.76 to 27.06; p < 0.001, and 14.98 pg/mL; 95% CI, 4.48 to 27.18; p = 0.007, respectively). Intact parathyroid hormone (iPTH) decreased in the cholecalciferol group (between-group difference in mean change -100.73 pg/mL (95% CI, -150.50 to -50.95; p < 0.001). Serum total and bone-specific alkaline phosphatase (SAP, BAP) and serum C-terminal cross-linked collagen type I telopeptides (CTX-1) were significantly reduced in cholecalciferol group (between group difference for change in mean: -20.25 U/L; 95% CI, -35.14 to -5.38 U/L; p = 0.008 for SAP; -12.54 U/L; 95% CI, -22.09 to -2.98 U/L; p = 0.013 for BAP; and -0.21 ng/mL; 95% CI, -0.38 to -0.05 ng/mL; p = 0.05 for CTX-1). Correlation analysis showed significant correlation of Δ25(OH)D with ΔiPTH (r = -0.409, p < 0.0001), Δ1,25(OH)2 D (r = 0.305, p = 0.001), ΔSAP (r = -0.301, p = 0.002), ΔBAP (r = -0.264, p = 0.004), and ΔCTX-1 (r = -0.210, p = 0.0230). Cholecalciferol supplementation corrects vitamin D deficiency and is effective in lowering serum intact parathyroid hormone and bone turnover markers in early stages of CKD. © 2017 American Society for Bone and Mineral Research.

A Randomized Trial of Vitamin D Supplementation on Vascular Function in CKD.

Vitamin D deficiency associates with mortality in patients with CKD, and vitamin D supplementation might mitigate cardiovascular disease risk in CKD. In this randomized, double-blind, placebo-controlled trial, we investigated the effect of cholecalciferol supplementation on vascular function in 120 patients of either sex, aged 18-70 years, with nondiabetic CKD stage 3-4 and vitamin D deficiency (serum 25-hydroxyvitamin D ≤20 ng/ml). We randomized patients using a 1:1 ratio to receive either two directly observed oral doses of cholecalciferol (300,000 IU) or matching placebo at baseline and 8 weeks. The primary outcome was change in endothelium-dependent brachial artery flow-mediated dilation at 16 weeks. Secondary outcome measures included changes in pulse wave velocity and circulating biomarkers. Cholecalciferol supplementation significantly increased endothelium-dependent brachial artery flow-mediated dilation at 16 weeks, whereas placebo did not (between-group difference in mean change: 5.49%; 95% confidence interval, 4.34% to 6.64%; P<0.001). Intervention also led to significant favorable changes in pulse wave velocity and circulating IL-6 levels. Thus, in nondiabetic patients with stage 3-4 CKD and vitamin D deficiency, vitamin D supplementation may improve vascular function. This study is registered with the Clinical Trials Registry of India (no.: CTRI/2013/05/003648).