Calciphylaxis Nigwekar, Sagar U; Thadhani, Ravi; Brandenburg, Vincent M
The New England journal of medicine,
05/2018, Volume:
378, Issue:
18
Journal Article
Peer reviewed
Calciphylaxis is a life-threatening disorder characterized by occlusion of microvessels in the subcutaneous adipose tissue and dermis. The authors outline the current understanding of calciphylaxis ...and provide a framework for interdisciplinary management.
Pre-eclampsia is a complication of pregnancy that is associated with substantial maternal and fetal morbidity and mortality. The disease presents with new-onset hypertension and often proteinuria in ...the mother, which can progress to multi-organ dysfunction, including hepatic, renal and cerebral disease, if the fetus and placenta are not delivered. Maternal endothelial dysfunction due to circulating factors of fetal origin from the placenta is a hallmark of pre-eclampsia. Risk factors for the disease include maternal comorbidities, such as chronic kidney disease, hypertension and obesity; a family history of pre-eclampsia, nulliparity or multiple pregnancies; and previous pre-eclampsia or intrauterine fetal growth restriction. In the past decade, the discovery and characterization of novel antiangiogenic pathways have been particularly impactful both in increasing understanding of the disease pathophysiology and in directing predictive and therapeutic efforts. In this Review, we discuss the pathogenic role of antiangiogenic proteins released by the placenta in the development of pre-eclampsia and review novel therapeutic strategies directed at restoring the angiogenic imbalance observed during pre-eclampsia. We also highlight other notable advances in the field, including the identification of long-term maternal and fetal risks conferred by pre-eclampsia.
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Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Calciphylaxis: Risk Factors, Diagnosis, and Treatment Nigwekar, Sagar U., MD, MMSc; Kroshinsky, Daniela, MD, MPH; Nazarian, Rosalynn M., MD ...
American journal of kidney diseases,
07/2015, Volume:
66, Issue:
1
Journal Article
Peer reviewed
Open access
Calciphylaxis is a rare but devastating condition that has continued to challenge the medical community since its early descriptions in the scientific literature many decades ago. It is predominantly ...seen in patients with chronic kidney failure treated with dialysis (uremic calciphylaxis) but is also described in patients with earlier stages of chronic kidney disease and with normal kidney function. In this review, we discuss the available medical literature regarding risk factors, diagnosis, and treatment of both uremic and nonuremic calciphylaxis. High-quality evidence for the evaluation and management of calciphylaxis is lacking at this time due to its rare incidence and poorly understood pathogenesis and the relative paucity of collaborative research efforts. We hereby provide a summary of recommendations developed by a multidisciplinary team for patients with calciphylaxis.
BACKGROUND—Dabigatran and rivaroxaban are new oral anticoagulants that are eliminated through the kidneys. Their use in dialysis patients is discouraged because these drugs can bioaccumulate to ...precipitate inadvertent bleeding. We wanted to determine whether prescription of dabigatran or rivaroxaban was occurring in the dialysis population and whether these practices were safe.
METHODS AND RESULTS—Prevalence plots were used to describe the point prevalence (monthly) of dabigatran and rivaroxaban use among 29 977 hemodialysis patients with atrial fibrillation. Poisson regression compared the rate of bleeding, stroke, and arterial embolism in patients who started dabigatran, rivaroxaban, or warfarin. The first record of dabigatran prescription among hemodialysis patients occurred 45 days after the drug became available in the United States. Since then, dabigatran and rivaroxaban use in the atrial fibrillation–end-stage renal disease population has steadily risen where 5.9% of anticoagulated dialysis patients are started on dabigatrian or rivaroxaban. In covariate adjusted Poisson regression, dabigatran (rate ratio, 1.48; 95% confidence interval, 1.21–1.81; P=0.0001) and rivaroxaban (rate ratio, 1.38; 95% confidence interval, 1.03–1.83; P=0.04) associated with a higher risk of hospitalization or death from bleeding when compared with warfarin. The risk of hemorrhagic death was even larger with dabigatran (rate ratio, 1.78; 95% confidence interval, 1.18–2.68; P=0.006) and rivaroxaban (rate ratio, 1.71; 95% confidence interval, 0.94–3.12; P=0.07) relative to warfarin. There were too few events in the study to detect meaningful differences in stroke and arterial embolism between the drug groups.
CONCLUSIONS—More dialysis patients are being started on dabigatran and rivaroxaban, even when their use is contraindicated and there are no studies to support that the benefits outweigh the risks of these drugs in end-stage renal disease.
Fibroblast growth factor 23 (FGF23) is a bone-derived hormone that controls blood phosphate levels by increasing renal phosphate excretion and reducing 1,25-dihydroxyvitamin D3 1,25(OH)2D production. ...Disorders of FGF23 homeostasis are associated with significant morbidity and mortality, but a fundamental understanding of what regulates FGF23 production is lacking. Because the kidney is the major end organ of FGF23 action, we hypothesized that it releases a factor that regulates FGF23 synthesis. Using aptamer-based proteomics and liquid chromatography-mass spectrometry-based (LC-MS-based) metabolomics, we profiled more than 1600 molecules in renal venous plasma obtained from human subjects. Renal vein glycerol-3-phosphate (G-3-P) had the strongest correlation with circulating FGF23. In mice, exogenous G-3-P stimulated bone and bone marrow FGF23 production through local G-3-P acyltransferase-mediated (GPAT-mediated) lysophosphatidic acid (LPA) synthesis. Further, the stimulatory effect of G-3-P and LPA on FGF23 required LPA receptor 1 (LPAR1). Acute kidney injury (AKI), which increases FGF23 levels, rapidly increased circulating G-3-P in humans and mice, and the effect of AKI on FGF23 was abrogated by GPAT inhibition or Lpar1 deletion. Together, our findings establish a role for kidney-derived G-3-P in mineral metabolism and outline potential targets to modulate FGF23 production during kidney injury.
Accurate identification of risk factors for calcific uremic arteriolopathy (CUA) is necessary to develop preventive strategies for this morbid disease. We investigated whether baseline factors ...recorded at hemodialysis initiation would identify patients at risk for future CUA in a matched case-control study using data from a large dialysis organization. Hemodialysis patients with newly diagnosed CUA (n=1030) between January 1, 2010, and December 31, 2014, were matched by age, sex, and race in a 1:2 ratio to hemodialysis patients without CUA (n=2060). Mean ages for patients and controls were 54 and 55 years, respectively; 67% of participants were women and 49% were white. Median duration between hemodialysis initiation and subsequent CUA development was 925 days (interquartile range, 273-2185 days). In multivariable conditional logistic regression analyses, diabetes mellitus; higher body mass index; higher levels of serum calcium, phosphorous, and parathyroid hormone; and nutritional vitamin D, cinacalcet, and warfarin treatments were associated with increased odds of subsequent CUA development. Compared with patients with diabetes receiving no insulin injections, those receiving insulin injections had a dose-response increase in the odds of CUA involving lower abdomen and/or upper thigh areas (odds ratio, 1.49; 95% confidence interval, 1.03 to 2.51 for one or two injections per day; odds ratio, 1.88; 95% confidence interval, 1.30 to 3.43 for 3 injections per day; odds ratio, 3.74; 95% confidence interval, 2.28 to 6.25 for more than three injections per day), suggesting a dose-effect relationship between recurrent skin trauma and CUA risk. The presence of risk factors months to years before CUA development observed in this study will direct the design of preventive strategies and inform CUA pathobiology.
Prior studies showed conflicting results regarding the association between 25-hydroxyvitamin D (25(OH)D) levels and mineral metabolism in end-stage renal disease. In order to determine whether the ...bioavailable vitamin D (that fraction not bound to vitamin D–binding protein) associates more strongly with measures of mineral metabolism than total levels, we identified 94 patients with previously measured 25(OH)D and 1,25-dihydroxyvitamin D (1,25(OH)2D) from a cohort of incident hemodialysis patients. Vitamin D–binding protein was measured from stored serum samples. Bioavailable 25(OH)D and 1,25(OH)2D were determined using previously validated formulae. Associations with demographic factors and measures of mineral metabolism were examined. When compared with whites, black patients had lower levels of total, but not bioavailable, 25(OH)D. Bioavailable, but not total, 25(OH)D and 1,25(OH)2D were each significantly correlated with serum calcium. In univariate and multivariate regression analysis, only bioavailable 25(OH)D was significantly associated with parathyroid hormone levels. Hence, bioavailable vitamin D levels are better correlated with measures of mineral metabolism than total levels in patients on hemodialysis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Few studies have evaluated whether histopathologic lesions on kidney biopsy provide prognostic information beyond clinical and laboratory data.
We enrolled 676 individuals undergoing native kidney ...biopsy at three tertiary care hospitals into a prospective, observational cohort study. Biopsy specimens were adjudicated for semiquantitative scores in 13 categories of histopathology by two experienced renal pathologists. Proportional hazards models tested the association between histopathologic lesions and risk of kidney disease progression (≥40% eGFR decline or RRT).
Mean baseline eGFR was 57.5±36.0 ml/min per 1.73 m
During follow-up (median, 34.3 months), 199 individuals suffered kidney disease progression. After adjustment for demographics, clinicopathologic diagnosis, and laboratory values, the following lesions (hazard ratio; 95% confidence interval) were independently associated with progression: inflammation in nonfibrosed interstitium (0.52; 0.32 to 0.83), moderate and severe versus minimal interstitial fibrosis/tubular atrophy (2.14; 1.24 to 3.69 and 3.42; 1.99 to 5.87, respectively), moderate and severe versus minimal global glomerulosclerosis (2.17; 1.36 to 3.45 and 3.31; 2.04 to 5.38, respectively), moderate and severe versus minimal arterial sclerosis (1.78; 1.15 to 2.74 and 1.64; 1.04 to 2.60, respectively), and moderate and severe versus minimal arteriolar sclerosis (1.63; 1.08 to 2.46 and 2.33; 1.42 to 3.83, respectively). An 11-point chronicity score derived from semiquantitative assessments of chronic lesions independently associated with higher risk of kidney disease progression (hazard ratio per one-point increase, 1.19; 95% confidence interval, 1.12 to 1.27).
Across a diverse group of kidney diseases, histopathologic lesions on kidney biopsy provide prognostic information, even after adjustment for proteinuria and eGFR.
This study shows that a polymorphism in the vitamin D–binding protein gene that is associated with low levels of vitamin D–binding protein among blacks results in levels of bioavailable vitamin D ...that are similar to those in whites, despite lower levels of total 25-hydroxyvitamin D among blacks.
Low levels of total 25-hydroxyvitamin D, which are more common in black Americans than in white Americans, are associated with negative health outcomes in epidemiologic studies.
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Such studies are responsible for the routine clinical practice of screening for vitamin D deficiency. Among the possible effects of vitamin D deficiency, the strongest evidence is for a role in skeletal disorders,
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but clinical investigations of vitamin D supplementation to decrease the risk of fracture have been inconclusive.
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Because blacks consistently have lower levels of total 25-hydroxyvitamin D than whites, they are frequently given a diagnosis of vitamin D deficiency. . . .
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