Instruct: Given a scientific claim, retrieve relevant documents that support or refute the claim.
Query: The US health care system can save up to $5 billion if 7% of patients waiting for kidney transplants participate in the optimized national kidney paired donation program.
CONTEXT Blood type and crossmatch incompatibility will exclude at least one third of patients in need from receiving a live donor kidney transplant. Kidney paired donation (KPD) offers incompatible donor/recipient pairs the opportunity to match for compatible transplants. Despite its increasing popularity, very few transplants have resulted from KPD. OBJECTIVE To determine the potential impact of improved matching schemes on the number and quality of transplants achievable with KPD. DESIGN, SETTING, AND POPULATION We developed a model that simulates pools of incompatible donor/recipient pairs. We designed a mathematically verifiable optimized matching algorithm and compared it with the scheme currently used in some centers and regions. Simulated patients from the general community with characteristics drawn from distributions describing end-stage renal disease patients eligible for renal transplantation and their willing and eligible live donors. MAIN OUTCOME MEASURES Number of kidneys matched, HLA mismatch of matched kidneys, and number of grafts surviving 5 years after transplantation. RESULTS A national optimized matching algorithm would result in more transplants (47.7% vs 42.0%, P<.001), better HLA concordance (3.0 vs 4.5 mismatched antigens; P<.001), more grafts surviving at 5 years (34.9% vs 28.7%; P<.001), and a reduction in the number of pairs required to travel (2.9% vs 18.4%; P<.001) when compared with an extension of the currently used first-accept scheme to a national level. Furthermore, highly sensitized patients would benefit 6-fold from a national optimized scheme (2.3% vs 14.1% successfully matched; P<.001). Even if only 7% of patients awaiting kidney transplantation participated in an optimized national KPD program, the health care system could save as much as $750 million. CONCLUSIONS The combination of a national KPD program and a mathematically optimized matching algorithm yields more matches with lower HLA disparity. Optimized matching affords patients the flexibility of customizing their matching priorities and the security of knowing that the greatest number of high-quality matches will be found and distributed equitably.
BACKGROUND Control of blood pressure (BP) following renal transplantation may improve allograft and patient survival. Our aims were (i) to describe the distribution of BP and the prevalence of systolic and/or diastolic hypertension in children over the first 5 years following renal transplantation and (ii) to evaluate clinical risk factors and centre-specific factors associated with hypertension in this population. METHODS We conducted a retrospective case note review of all current paediatric kidney transplant patients in the UK, with data collected at 6 months, 1, 2 and 5 years following transplantation in subjects with hypertension (systolic and/or diastolic BP > 95th > ) and non-hypertensive subjects BP ≤ 95th > . RESULTS In total, 27.3% (117/428), 27.6% (118/428), 26.0% (95/365) and 25.6% (50/195) of the patients were hypertensive (systolic and/or diastolic BP > 95th > ) at 6 months, 1, 2 and 5 years following transplantation, respectively. A total of 58.4% of the patients at 6 months, 52.8% at 1 year, 48.2% at 2 years and 48.2% at 5 years were receiving anti-hypertensive therapy, of whom 31.6-36.6% remained hypertensive. When subjects were identified as being hypertensive, on anti-hypertensive medication or had untreated hypertension (systolic and/or diastolic BP > 95th > ), 66.4, 61.0, 56.4 and 55.9% of patients were hypertensive at 6 months, 1, 2 and 5 years, respectively. In a multivariate model, odds ratios for systolic hypertension were 4.16 (deceased versus living donor), 2.65 (lowest versus highest quartile of height z-score) and 2.07 (if on anti-hypertensive; yes versus no). There was significant variation in prevalent rates of hypertension between centres (P < 0.0001) that remained significant (P = 0.003) after adjustment for all the factors in the multivariate model. CONCLUSIONS Control of BP after kidney transplantation remains sub-optimal in paediatric centres in the UK. Just over 25% of patients remain hypertensive 5 years following transplantation. Significant differences between centres remain unexplained and may reflect differences in assessment and management of hypertension.
CONTEXT High plasma homocysteine levels are a risk factor for mortality and vascular disease in observational studies of patients with chronic kidney disease. Folic acid and B vitamins decrease homocysteine levels in this population but whether they lower mortality is unknown. OBJECTIVE To determine whether high doses of folic acid and B vitamins administered daily reduce mortality in patients with chronic kidney disease. DESIGN, SETTING, AND PARTICIPANTS Double-blind randomized controlled trial (2001-2006) in 36 US Department of Veterans Affairs medical centers. Median follow-up was 3.2 years for 2056 participants aged 21 years or older with advanced chronic kidney disease (estimated creatinine clearance < or =30 mL/min) (n = 1305) or end-stage renal disease (n = 751) and high homocysteine levels (> or = 15 micromol/L). INTERVENTION Participants received a daily capsule containing 40 mg of folic acid, 100 mg of pyridoxine hydrochloride (vitamin B6), and 2 mg of cyanocobalamin (vitamin B12) or a placebo. MAIN OUTCOME MEASURES The primary outcome was all-cause mortality. Secondary outcomes included myocardial infarction (MI), stroke, amputation of all or part of a lower extremity, a composite of these 3 plus all-cause mortality, time to initiation of dialysis, and time to thrombosis of arteriovenous access in hemodialysis patients. RESULTS Mean baseline homocysteine level was 24.0 micromol/L in the vitamin group and 24.2 micromol/L in the placebo group. It was lowered 6.3 micromol/L (25.8%; P < .001) in the vitamin group and 0.4 micromol/L (1.7%; P = .14) in the placebo group at 3 months, but there was no significant effect on mortality (448 vitamin group deaths vs 436 placebo group deaths) (hazard ratio [HR], 1.04; 95% CI, 0.91-1.18). No significant effects were demonstrated for secondary outcomes or adverse events: there were 129 MIs in the vitamin group vs 150 for placebo (HR, 0.86; 95% CI, 0.67-1.08), 37 strokes in the vitamin group vs 41 for placebo (HR, 0.90; 95% CI, 0.58-1.40), and 60 amputations in the vitamin group vs 53 for placebo (HR, 1.14; 95% CI, 0.79-1.64). In addition, the composite of MI, stroke, and amputations plus mortality (P = .85), time to dialysis (P = .38), and time to thrombosis in hemodialysis patients (P = .97) did not differ between the vitamin and placebo groups. CONCLUSION Treatment with high doses of folic acid and B vitamins did not improve survival or reduce the incidence of vascular disease in patients with advanced chronic kidney disease or end-stage renal disease. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00032435.
BACKGROUND The Avoiding Cardiovascular Events through Combination Therapy in Patients Living with Systolic Hypertension (ACCOMPLISH) trial showed that initial antihypertensive therapy with benazepril plus amlodipine was superior to benazepril plus hydrochlorothiazide in reducing cardiovascular morbidity and mortality. We assessed the effects of these drug combinations on progression of chronic kidney disease. METHODS ACCOMPLISH was a double-blind, randomised trial undertaken in five countries (USA, Sweden, Norway, Denmark, and Finland). 11 506 patients with hypertension who were at high risk for cardiovascular events were randomly assigned via a central, telephone-based interactive voice response system in a 1:1 ratio to receive benazepril (20 mg) plus amlodipine (5 mg; n=5744) or benazepril (20 mg) plus hydrochlorothiazide (12.5 mg; n=5762), orally once daily. Drug doses were force-titrated for patients to attain recommended blood pressure goals. Progression of chronic kidney disease, a prespecified endpoint, was defined as doubling of serum creatinine concentration or end-stage renal disease (estimated glomerular filtration rate <15 mL/min/1.73 m(2) or need for dialysis). Analysis was by intention to treat (ITT). This trial is registered with ClinicalTrials.gov, number NCT00170950. FINDINGS The trial was terminated early (mean follow-up 2.9 years [SD 0.4]) because of superior efficacy of benazepril plus amlodipine compared with benazepril plus hydrochlorothiazide. At trial completion, vital status was not known for 143 (1%) patients who were lost to follow-up (benazepril plus amlodipine, n=70; benazepril plus hydrochlorothiazide, n=73). All randomised patients were included in the ITT analysis. There were 113 (2.0%) events of chronic kidney disease progression in the benazepril plus amlodipine group compared with 215 (3.7%) in the benazepril plus hydrochlorothiazide group (HR 0.52, 0.41-0.65, p<0.0001). The most frequent adverse event in patients with chronic kidney disease was peripheral oedema (benazepril plus amlodipine, 189 of 561, 33.7%; benazepril plus hydrochlorothiazide, 85 of 532, 16.0%). In patients with chronic kidney disease, angio-oedema was more frequent in the benazepril plus amlodipine group than in the benazepril plus hydrochlorothiazide group. In patients without chronic kidney disease, dizziness, hypokalaemia, and hypotension were more frequent in the benazepril plus hydrochlorothiazide group than in the benazepril plus amlodipine group. INTERPRETATION Initial antihypertensive treatment with benazepril plus amlodipine should be considered in preference to benazepril plus hydrochlorothiazide since it slows progression of nephropathy to a greater extent. FUNDING Novartis.
BACKGROUND Diabetic nephropathy is the leading cause of end-stage renal disease in developed countries. We evaluated the renoprotective effects of dual blockade of the renin-angiotensin-aldosterone system by adding treatment with aliskiren, an oral direct renin inhibitor, to treatment with the maximal recommended dose of losartan (100 mg daily) and optimal antihypertensive therapy in patients who had hypertension and type 2 diabetes with nephropathy. METHODS We enrolled 599 patients in this multinational, randomized, double-blind study. After a 3-month, open-label, run-in period during which patients received 100 mg of losartan daily, patients were randomly assigned to receive 6 months of treatment with aliskiren (150 mg daily for 3 months, followed by an increase in dosage to 300 mg daily for another 3 months) or placebo, in addition to losartan. The primary outcome was a reduction in the ratio of albumin to creatinine, as measured in an early-morning urine sample, at 6 months. RESULTS The baseline characteristics of the two groups were similar. Treatment with 300 mg of aliskiren daily, as compared with placebo, reduced the mean urinary albumin-to-creatinine ratio by 20% (95% confidence interval, 9 to 30; P<0.001), with a reduction of 50% or more in 24.7% of the patients who received aliskiren as compared with 12.5% of those who received placebo (P<0.001). A small difference in blood pressure was seen between the treatment groups by the end of the study period (systolic, 2 mm Hg lower [P=0.07] and diastolic, 1 mm Hg lower [P=0.08] in the aliskiren group). The total numbers of adverse and serious adverse events were similar in the groups. CONCLUSIONS Aliskiren may have renoprotective effects that are independent of its blood-pressure-lowering effect in patients with hypertension, type 2 diabetes, and nephropathy who are receiving the recommended renoprotective treatment. (ClinicalTrials.gov number, NCT00097955 [ClinicalTrials.gov].).
The rat kidney ablation and infarction (A/I) model of subtotal or 5/6th nephrectomy is the most commonly studied model of nondiabetic chronic kidney disease (CKD). The A/I kidney at 1 wk exhibits reductions in kidney function, as determined by glomerular filtration rate, and diminished metabolic efficiency as determined by oxygen consumption per sodium transport (QO2/TNa). As renoprotective AMPK activity is affected by metabolic changes and cellular stress, we evaluated AMPK activity in this model system. We show that these early pathophysiological changes are accompanied by a paradoxical decrease in AMPK activity. Over time, these kidney parameters progressively worsen with extensive kidney structural, functional, metabolic, and fibrotic changes observed at 4 wk after A/I. We show that induction of AMPK activity with either metformin or 5-aminoimidazole-4-carboxamide ribonucleotide increases AMPK activity in this model and also corrects kidney metabolic inefficiency, improves kidney function, and ameliorates kidney fibrosis and structural alterations. We conclude that AMPK activity is reduced in the subtotal nephrectomy model of nondiabetic CKD, that altered regulation of AMPK is coincident with the progression of disease parameters, and that restoration of AMPK activity can suppress the progressive loss of function characteristic of this model. We propose that induction of AMPK activity may prove an effective therapeutic target for the treatment of nondiabetic CKD.
BACKGROUND Hydroxyethyl starches (HES) are synthetic colloids commonly used for fluid resuscitation, yet controversy exists about their impact on kidney function. OBJECTIVES To examine the effects of HES on kidney function compared to other fluid resuscitation therapies in different patient populations. SEARCH STRATEGY We searched the Cochrane Renal Group's specialised register, the Cochrane Central Register of Controlled Trials (CENTRAL, in The Cochrane Library), MEDLINE, EMBASE, MetaRegister and reference lists of articles. SELECTION CRITERIA Randomised controlled trials (RCTs) and quasi-RCTs in which HES was compared to an alternate fluid therapy for the prevention or treatment of effective intravascular volume depletion. Primary outcomes were renal replacement therapy (RRT), author-defined kidney failure and acute kidney injury (AKI) as defined by the RIFLE criteria. Secondary outcomes included serum creatinine and creatinine clearance. DATA COLLECTION AND ANALYSIS Screening, selection, data extraction and quality assessments for each retrieved article were carried out by two authors using standardised forms. Authors were contacted when published data were incomplete. Preplanned sensitivity and subgroup analyses were performed after data were analysed with a random effects model. MAIN RESULTS The review included 34 studies (2607 patients). Overall, the RR of author-defined kidney failure was 1.50 (95% CI 1.20 to 1.87; n = 1199) and 1.38 for requiring RRT (95% CI 0.89 to 2.16; n = 1236) in HES treated individuals compared with other fluid therapies. Subgroup analyses suggested increased risk in septic patients compared to non-septic (surgical/trauma) patients. Non-septic patient studies were smaller and had lower event rates, so subgroup differences may have been due to lack of statistical power in these studies. Only limited data was obtained for analysis of kidney outcomes by the RIFLE criteria. Overall, methodological quality of studies was good but subjective outcomes were potentially biased because most studies were unblinded. AUTHORS' CONCLUSIONS Potential for increased risk of AKI should be considered when weighing the risks and benefits of HES for volume resuscitation, particularly in septic patients. Large studies with adequate follow-up are required to evaluate the renal safety of HES products in non-septic patient populations. RIFLE criteria should be applied to evaluate kidney function in future studies of HES and, where data is available, to re-analyse those studies already published. There is inadequate clinical data to address the claim that safety differences exist between different HES products.
The incidence of chronic kidney diseases is increasing worldwide, and these conditions are emerging as a major public health problem. While genetic factors contribute to susceptibility and progression of renal disease, proteinuria has been claimed as an independent predictor of outcome. Reduction of urinary protein levels by various medications and a low-protein diet limits renal function decline in individuals with nondiabetic and diabetic nephropathies to the point that remission of the disease and regression of renal lesions have been observed in experimental animals and even in humans. In animal models, regression of glomerular structural changes is associated with remodeling of the glomerular architecture. Instrumental to this discovery were 3D reconstruction studies of the glomerular capillary tuft, which allowed the quantification of sclerosis volume reduction and capillary regeneration upon treatment. Regeneration of capillary segments might result from the contribution of resident cells, but progenitor cells of renal or extrarenal origin may also have a role. This review describes recent advances in our understanding of the mechanisms and mediators underlying renal tissue repair ultimately responsible for regression of renal injury.
CONTEXT A number of countries have implemented a policy of universal leukoreduction of their blood supply, but the potential role of leukoreduction in decreasing postoperative mortality and infection is unclear. OBJECTIVE To evaluate clinical outcomes following adoption of a national universal prestorage leukoreduction program for blood transfusions. DESIGN, SETTING, AND POPULATION Retrospective before-and-after cohort study conducted from August 1998 to August 2000 in 23 academic and community hospitals throughout Canada, enrolling 14 786 patients who received red blood cell transfusions following cardiac surgery or repair of hip fracture, or who required intensive care following a surgical intervention or multiple trauma. INTERVENTION Universal prestorage leukoreduction program introduced by 2 Canadian blood agencies. A total of 6982 patients were enrolled during the control period and 7804 patients were enrolled following prestorage leukoreduction. MAIN OUTCOME MEASURES All-cause in-hospital mortality and serious nosocomial infections (pneumonia, bacteremia, septic shock, all surgical site infections) occurring after first transfusion and at least 2 days after index procedure or intensive care unit admission. Secondary outcomes included rates of posttransfusion fever and antibiotic use. RESULTS Unadjusted in-hospital mortality rates were significantly lower following the introduction of leukoreduction compared with the control period (6.19% vs 7.03%, respectively; P =.04). Compared with the control period, the adjusted odds of death following leukoreduction were reduced (odds ratio [OR], 0.87; 95% confidence interval [CI], 0.75-0.99), but serious nosocomial infections did not decrease (adjusted OR, 0.97; 95% CI, 0.87-1.09). The frequency of posttransfusion fevers decreased significantly following leukoreduction (adjusted OR, 0.86; 95% CI, 0.79-0.94), as did antibiotic use (adjusted OR, 0.90; 95% CI, 0.82-0.99). CONCLUSION A national universal leukoreduction program is potentially associated with decreased mortality as well as decreased fever episodes and antibiotic use after red blood cell transfusion in high-risk patients.
The previous conventional wisdom that survivors of acute kidney injury (AKI) tend to do well and fully recover renal function appears to be flawed. AKI can cause end-stage renal disease (ESRD) directly, and increase the risk of developing incident chronic kidney disease (CKD) and worsening of underlying CKD. In addition, severity, duration, and frequency of AKI appear to be important predictors of poor patient outcomes. CKD is an important risk factor for the development and ascertainment of AKI. Experimental data support the clinical observations and the bidirectional nature of the relationships between AKI and CKD. Reductions in renal mass and nephron number, vascular insufficiency, cell cycle disruption, and maladaptive repair mechanisms appear to be important modulators of progression in patients with and without coexistent CKD. Distinction between AKI and CKD may be artificial. Consideration should be given to the integrated clinical syndrome of diminished GFR, with acute and chronic stages, where spectrum of disease state and outcome is determined by host factors, including the balance of adaptive and maladaptive repair mechanisms over time. Physicians must provide long-term follow-up to patients with first episodes of AKI, even if they presented with normal renal function.
BACKGROUND Being overweight is often cited as a relative contraindication to peritoneal dialysis. Our primary objective was to determine whether actual mortality rates support this opinion. METHODS Retrospective cohort study of United States Medicare patients initiating dialysis between 1995 and 2000 (N = 418,021; 11% peritoneal dialysis). RESULTS Seven percent were underweight [body mass index (BMI) < 18.5 kg/m2], 27% were overweight (BMI 25.0 to 29.9 kg/m2), and 23% were obese (BMI> 29.9 kg/m2) at dialysis initiation. Compared to those with normal BMI, the adjusted odds of initiating peritoneal dialysis were 0.70 (P < 0.05) in underweight, 1.12 (P < 0.05) in overweight, and 0.87 (P < 0.05) in obese subjects. Among peritoneal dialysis patients, adjusted mortality hazard ratios in the first, second, and third year were 1.45 (P < 0.05), 1.28 (P < 0.05), and 1.17 for the underweight, respectively; 0.84 (P < 0.05), 0.89 (P < 0.05), and 0.98 for the overweight, respectively; and 0.89 (P < 0.05), 0.99, and 1.00 for the obese, respectively. Apart from higher third-year mortality in the obese, associations were similar after censoring at a switch to hemodialysis. For transplantation, the corresponding results were 0.76 (P < 0.05), 0.90 (P < 0.05), and 0.88 for the underweight, respectively; 0.95, 1.06, and 0.93 for the overweight, respectively; and 0.62 (P < 0.05), 0.68, and 0.71 for the obese, respectively. For switching to hemodialysis, hazards ratios were 0.92, 0.97, and 0.80 for the underweight, respectively; 1.07, 1.11 (P < 0.05), and 1.03 for the overweight, respectively; and 1.28 (P < 0.05), 1.29 (P < 0.05), and 1.36 (P < 0.05) for the obese, respectively. CONCLUSION Although less likely to initiate peritoneal dialysis, overweight and obese peritoneal dialysis patients have longer survival than those with lower BMI, not adequately explained by lower transplantation and technique survival rates.
BACKGROUND Angiotensin receptor blockers (ARB) and angiotensin converting enzyme (ACE) inhibitors are known to reduce proteinuria. Their combination might be more effective than either treatment alone, but long-term data for comparative changes in renal function are not available. We investigated the renal effects of ramipril (an ACE inhibitor), telmisartan (an ARB), and their combination in patients aged 55 years or older with established atherosclerotic vascular disease or with diabetes with end-organ damage. METHODS The trial ran from 2001 to 2007. After a 3-week run-in period, 25 620 participants were randomly assigned to ramipril 10 mg a day (n=8576), telmisartan 80 mg a day (n=8542), or to a combination of both drugs (n=8502; median follow-up was 56 months), and renal function and proteinuria were measured. The primary renal outcome was a composite of dialysis, doubling of serum creatinine, and death. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00153101. FINDINGS 784 patients permanently discontinued randomised therapy during the trial because of hypotensive symptoms (406 on combination therapy, 149 on ramipril, and 229 on telmisartan). The number of events for the composite primary outcome was similar for telmisartan (n=1147 [13.4%]) and ramipril (1150 [13.5%]; hazard ratio [HR] 1.00, 95% CI 0.92-1.09), but was increased with combination therapy (1233 [14.5%]; HR 1.09, 1.01-1.18, p=0.037). The secondary renal outcome, dialysis or doubling of serum creatinine, was similar with telmisartan (189 [2.21%]) and ramipril (174 [2.03%]; HR 1.09, 0.89-1.34) and more frequent with combination therapy (212 [2.49%]: HR 1.24, 1.01-1.51, p=0.038). Estimated glomerular filtration rate (eGFR) declined least with ramipril compared with telmisartan (-2.82 [SD 17.2] mL/min/1.73 m(2)vs -4.12 [17.4], p<0.0001) or combination therapy (-6.11 [17.9], p<0.0001). The increase in urinary albumin excretion was less with telmisartan (p=0.004) or with combination therapy (p=0.001) than with ramipril. INTERPRETATION In people at high vascular risk, telmisartan's effects on major renal outcomes are similar to ramipril. Although combination therapy reduces proteinuria to a greater extent than monotherapy, overall it worsens major renal outcomes.
CONTEXT The antioxidant acetylcysteine prevents acute contrast nephrotoxicity in patients with impaired renal function who undergo computed tomography scanning. However, its role in coronary angiography is unclear. OBJECTIVE To determine whether oral acetylcysteine prevents acute deterioration in renal function in patients with moderate renal insufficiency who undergo elective coronary angiography. DESIGN AND SETTING Prospective, randomized, double-blind, placebo-controlled trial conducted from May 2000 to December 2001 at the Grantham Hospital at the University of Hong Kong. PARTICIPANTS Two hundred Chinese patients aged mean (SD) 68 (6.5) years with stable moderate renal insufficiency (creatinine clearance <60 mL/min [1.00 mL/s]) who were undergoing elective coronary angiography with or without intervention. INTERVENTION Participants were randomly assigned to receive oral acetylcysteine(600 mg twice per day; n = 102) or matching placebo tablets (n = 98) on the day before and the day of angiography. All patients received low-osmolality contrast agent. MAIN OUTCOME MEASURES Occurrence of more than a 25% increase in serum creatinine level within 48 hours after contrast administration; change in creatinine clearance and serum creatinine level. RESULTS Twelve control patients (12%) and 4 acetylcysteine patients (4%) developed a more than 25% increase in serum creatinine level within 48 hours after contrast administration (relative risk, 0.32; 95% confidence interval [CI], 0.10-0.96; P =.03). Serum creatinine was lower in the acetylcysteine group (1.22 mg/dL [107.8 micromol/L]; 95% CI, 1.11-1.33 mg/dL vs 1.38 mg/dL [122.9 micromol/L]; 95% CI, 1.27-1.49 mg/dL; P =.006) during the first 48 hours after angiography. Acetylcysteine treatment significantly increased creatinine clearance from 44.8 mL/min (0.75 mL/s) (95% CI, 42.7-47.6 mL/min) to 58.9 mL/min (0.98 mL/s) (95% CI, 55.6-62.3 mL/min) 2 days after the contrast administration (P<.001). The increase was not significant in the control group (from 42.1 to 44.1 mL/min [0.70 to 0.74 mL/s]; P =.15). The benefit of acetylcysteine was consistent among various patient subgroups and persistent for at least 7 days. There were no major treatment-related adverse events. CONCLUSION Acetylcysteine protects patients with moderate chronic renal insufficiency from contrast-induced deterioration in renal function after coronary angiographic procedures, with minimal adverse effects and at a low cost.
Pregnancy in women with different renal diseases has important consequences for the developing fetus and maternal health. Kidneys and the urinary tract have to adapt to the pregnancy status and therefore suffer significant anatomical, hemodynamic and endocrine changes. Failure to adapt can aggravate the preexisting maternal disease and can also create suboptimal environment for fetal development and increase the risk of obstetric complications. Knowledge and correct interpretation of the renal functional tests is necessary for the modern obstetrician, avoiding an incorrect diagnosis for renal disease where only specific renal changes during pregnancy are present, but meanwhile a correct evaluation of the renal function and changes can detect a pathology that can aggravate both the mother’s and the baby’s condition. Improvement and better understanding of the renal pathophysiology in pregnancy made possible that pregnant woman look forward for a good outcome, including here also the women with renal transplant. Nowadays is underlined the concept of multidisciplinary teamwork, a very important concept of modern medicine. The obstetrician should consider nephrologists as key players in the team and in our opinion should refer to them the pregnant women for a routine check-up of the renal status in the 2nd or beginning of 3rd trimester by ultrasound, beside the usual blood and urine analysis. The nephrologists and urologists should be involved in the management of severe medical conditions, such as preeclampsia, acute and chronic renal failure and never the less in the complex management of dialysis or renal transplant patients. In pregnancy it can be encountered several renal diseases, some of them preexisting the pregnancy and other developed or being direct influenced by pregnancy. This chapter will discuss briefly the basic evaluation of renal status in order to present and better understand the acute and chronic renal disorders in pregnancy. The chapter will focus on the most common preexisting diseases in pregnancy such as: chronic glomerulonephritis, secondary glomerular nephropathies, interstitial nephropathies (chronic pyelonephritis, renal tuberculosis), diabetes nephropathy, unique surgical kidney, chronic renal failure. From the renal diseases directly influenced by pregnancy it will be discussed: asymptomatic bacteriuria, symptomatic urinary infection, urolithiasis and acute renal failure in pregnancy. It will be presented also the management of dialysis in pregnancy and pregnant women with renal transplant.
BACKGROUND The absolute risk of fractures in renal transplant patients is 3 times that of matched controls. Most of the symptomatic fractures are peripheral, suggesting a greater compromise of cortical bone. Peripheral quantitative computed tomography (pQCT) is a new imaging technique that allows separate noninvasive evaluations of cortical and trabecular bones. We investigated cortical bone by pQCT in 12 renal transplant patients (seven men and five women) for comparison with 27 normal controls. METHODS pQCT (XCT 960, Stratec, Pforheim, Germany) was performed upon the distal radius of the nondominant forearm (15% the length of the ulna, proximal from the radius end plate). We evaluated total and cortical bone mineral density (TBMD, cBMD), total (cross-sectional) and cortical area (TA, cA), cortical thickness (cThk), endosteal and periosteal circumferences, and the buckling ratio (r/cThK). RESULTS Compared with normal controls transplant patients as a whole showed a significant increase in TA, in endosteal circumference (P < .001), and in the buckling ratio (P < .001) with a significant reduction in cThK (P < .001). Female patients had a marked decrease in cA (51.4 vs 69.3 [pixel n]; P < .0001) and cThK (2.08 vs 2.78 mm; P < .0001). Male patients also had a decrease in cThK (2.54 vs 3.30 mm; P = .0001) and an increase in endosteal perimeter (31.2 vs 26.4 mm; P < .0001). Total time on dialysis prior to renal graft correlated negatively with cortical thickness (r = .62; P < .01). CONCLUSIONS Our results suggest that a marked thinning of cortical bone may explain the increased incidence of peripheral fractures among renal transplant patients.
The risk of HCV transmission by blood and blood products has been greatly reduced since the early 1980's. Selection of non-remunerated donors, donor selection to prevent HIV transmission, initial surrogate testing in some regions, and introduction of anti-HCV testing have all contributed to this. ALT surrogate testing has become obsolete since the introduction of anti-HCV testing. The residual risk of HCV transmission due to donations in the anti-HCV window period at present is about 1 in 100 000 transfusions of cellular products, and transmission of HCV by plasma products treated with modern inactivation methods such as solvent-detergent treatment, has not been reported. Hemovigilance programmes, which are presently being installed, will provide more data on the safety of blood transfusion. Introduction of HCV nucleic amplification technology (NAT) as a quality control of manufacturing pools for plasma products or as a form of blood donor screening by minipools is anticipated in many European countries for the coming year. Given industrial developments, NAT testing of individual blood donations may become available within the next 2 years. HCV NAT testing will further annihilate the residual risk, and the cost-effectiveness will become relatively low in comparison with other public health measures.
Acute kidney injury (AKI) is a complex disorder comprising several etiological factors and occurring in multiple settings. The disorder has a variety of clinical manifestations that range from minimal elevation in serum creatinine level to anuric renal failure. We describe the formation of a multidisciplinary collaborative network focused on AKI. This Acute Kidney Injury Network has proposed uniform standards for diagnosing and classifying AKI. These proposed standards will need to be validated in future studies, a process that will be facilitated by the Acute Kidney Injury Network, which offers a forum that encourages acquisition of knowledge to improve patient outcomes.
BACKGROUND Radiographic contrast agents can cause a reduction in renal function that may be due to reactive oxygen species. Whether the reduction can be prevented by the administration of antioxidants is unknown. METHODS We prospectively studied 83 patients with chronic renal insufficiency (mean [+/-SD] serum creatinine concentration, 2.4+/-1.3 mg per deciliter [216+/-116 micromol per liter]) who were undergoing computed tomography with a nonionic, low-osmolality contrast agent. Patients were randomly assigned either to receive the antioxidant acetylcysteine (600 mg orally twice daily) and 0.45 percent saline intravenously, before and after administration of the contrast agent, or to receive placebo and saline. RESULTS Ten of the 83 patients (12 percent) had an increase of at least 0.5 mg per deciliter (44 micromol per liter) in the serum creatinine concentration 48 hours after administration of the contrast agent: 1 of the 41 patients in the acetylcysteine group (2 percent) and 9 of the 42 patients in the control group (21 percent; P=0.01; relative risk, 0.1; 95 percent confidence interval, 0.02 to 0.9). In the acetylcysteine group, the mean serum creatinine concentration decreased significantly (P<0.001), from 2.5+/-1.3 to 2.1+/-1.3 mg per deciliter (220+/-118 to 186+/-112 micromol per liter) 48 hours after the administration of the contrast medium, whereas in the control group, the mean serum creatinine concentration increased nonsignificantly (P=0.18), from 2.4+/-1.3 to 2.6+/-1.5 mg per deciliter (212+/-114 to 226+/-133 micromol per liter) (P<0.001 for the comparison between groups). CONCLUSIONS Prophylactic oral administration of the antioxidant acetylcysteine, along with hydration, prevents the reduction in renal function induced by contrast agents in patients with chronic renal insufficiency.
OBJECTIVE To estimate the lost investment of domestically educated doctors migrating from sub-Saharan African countries to Australia, Canada, the United Kingdom, and the United States. DESIGN Human capital cost analysis using publicly accessible data. SETTINGS Sub-Saharan African countries. PARTICIPANTS Nine sub-Saharan African countries with an HIV prevalence of 5% or greater or with more than one million people with HIV/AIDS and with at least one medical school (Ethiopia, Kenya, Malawi, Nigeria, South Africa, Tanzania, Uganda, Zambia, and Zimbabwe), and data available on the number of doctors practising in destination countries. MAIN OUTCOME MEASURES The financial cost of educating a doctor (through primary, secondary, and medical school), assuming that migration occurred after graduation, using current country specific interest rates for savings converted to US dollars; cost according to the number of source country doctors currently working in the destination countries; and savings to destination countries of receiving trained doctors. RESULTS In the nine source countries the estimated government subsidised cost of a doctor's education ranged from $21,000 (£13,000; €15,000) in Uganda to $58,700 in South Africa. The overall estimated loss of returns from investment for all doctors currently working in the destination countries was $2.17bn (95% confidence interval 2.13bn to 2.21bn), with costs for each country ranging from $2.16m (1.55m to 2.78m) for Malawi to $1.41bn (1.38bn to 1.44bn) for South Africa. The ratio of the estimated compounded lost investment over gross domestic product showed that Zimbabwe and South Africa had the largest losses. The benefit to destination countries of recruiting trained doctors was largest for the United Kingdom ($2.7bn) and United States ($846m). CONCLUSIONS Among sub-Saharan African countries most affected by HIV/AIDS, lost investment from the emigration of doctors is considerable. Destination countries should consider investing in measurable training for source countries and strengthening of their health systems.
BACKGROUND Dual eligibles, persons who qualify for both Medicare and Medicaid coverage, often receive poorer quality care relative to other Medicare beneficiaries. OBJECTIVES To determine whether dual eligibles are discharged to lower quality post-acute skilled nursing facilities (SNFs) compared with Medicare-only beneficiaries. RESEARCH DESIGN Following the random utility maximization model, we specified a discharge function using a conditional logit model and tested how this discharge rule varied by dual-eligibility status. SUBJECTS A total of 692,875 Medicare fee-for-service patients (22% duals) who were discharged for Medicare paid SNF care between July 2004 and June 2005. MEASURES Medicare enrollment and the Medicaid Analytic Extract files were used to determine dual eligibility. The proportion of Medicaid patients and nursing staff characteristics provided measures of SNF quality. RESULTS Duals are more likely to be discharged to SNFs with a higher share of Medicaid patients and fewer nurses. These results are robust to estimation with an alternative subsample of patients based on primary diagnoses, propensity of being dual eligible, and likelihood of remaining in the nursing home. CONCLUSIONS Disparities exist in access to quality SNF care for duals. Strategies to improve discharge planning processes are required to redirect patients to higher quality providers, regardless of Medicaid eligibility.
BACKGROUND Since 2004, several reported transfusion transmissions of variant Creutzfeldt-Jakob disease (vCJD) in the United Kingdom have reawakened concerns about the possible risk of similar transmissions of nonvariant or classic forms of CJD. STUDY DESIGN AND METHODS Patients with a CJD diagnosis and a history of donating blood were reported to the study coordinator. Through review of blood distribution and hospital records, the recipients of blood components from these donors were identified. We then determined each recipient's vital status and, if deceased, the cause(s) of death identified by matching the recipient's personal identifiers with the Centers for Disease Control and Prevention's National Death Index database. We conducted such searches after recipients were enrolled in this study and annually thereafter for those who remained alive. RESULTS The study included a total of 36 blood donors who subsequently developed CJD and 436 recipients. Through 2006, 91 of these recipients were still alive, 329 were deceased, and 16 were lost to follow-up. After transfusion, these three groups had survived a total of 2096.0 person-years. A total of 144 recipients survived 5 years or longer after transfusion and 68 of them had received blood donated 60 or fewer months before the onset of CJD in the donor. We identified no recipient with CJD. CONCLUSIONS The current results of this large, ongoing lookback study show no evidence of transfusion transmission of CJD. They reinforce the conclusion that the risk, if any, of transfusion transmission of prion disease by CJD donors is significantly lower than the comparable risk of such transmission by vCJD donors.
BACKGROUND The Italian National Health Service (NHS) provides universal coverage to all citizens, granting primary and hospital care with a copayment system for outpatient and drug services. Financing of Local Health Trusts (LHTs) is based on a capitation system adjusted only for age, gender and area of residence. We applied a risk-adjustment system (Johns Hopkins Adjusted Clinical Groups System, ACG® System) in order to explain health care costs using routinely collected administrative data in the Veneto Region (North-eastern Italy). METHODS All residents in the Veneto Region were included in the study. The ACG system was applied to classify the regional population based on the following information sources for the year 2015: Hospital Discharges, Emergency Room visits, Chronic disease registry for copayment exemptions, ambulatory visits, medications, the Home care database, and drug prescriptions. Simple linear regressions were used to contrast an age-gender model to models incorporating more comprehensive risk measures aimed at predicting health care costs. RESULTS A simple age-gender model explained only 8% of the variance of 2015 total costs. Adding diagnoses-related variables provided a 23% increase, while pharmacy based variables provided an additional 17% increase in explained variance. The adjusted R-squared of the comprehensive model was 6 times that of the simple age-gender model. CONCLUSIONS ACG System provides substantial improvement in predicting health care costs when compared to simple age-gender adjustments. Aging itself is not the main determinant of the increase of health care costs, which is better explained by the accumulation of chronic conditions and the resulting multimorbidity.
The present study retrospectively analyzed 19 patients diagnosed with paraquat (PQ) poisoning with the aim to investigate the effect of activated charcoal hemoperfusion on renal function and PQ elimination. The results indicated that 7 patients died and 12 survived. Non-oliguric renal failure occurred in all of the 7 patients who died. Among the 12 surviving patients, 10 had normal renal function and 2 developed non-oliguric renal failure. There was a linear correlation between plasma and urine paraquat concentration prior to and during activated charcoal hemoperfusion. The equation parameters together with the correlation coefficient on admission were as follows: Y=0.5820+1.7348X (R2=0.678; F=35.768; P<0.0001). The equation parameters together with the correlation coefficient were as follows during activated charcoal hemoperfusion: Y=0.6827+1.2649X (R2=0.626; F=50.308; P<0.0001). Therefore, it was concluded that in patients with normal renal function, the elimination kinetics of PQ by the kidneys were only associated with the plasma PQ concentration. Activated charcoal hemoperfusion had little effect on avoiding acute kidney injury in patients with severe PQ poisoning.
BACKGROUND The pathophysiological mechanism of hyperhomocysteinemia in chronic renal failure in humans is unknown. The loss of a putative renal homocysteine extraction in chronic renal failure has been hypothesized as significant homocysteine uptake has been demonstrated in the normal rat kidney. We studied homocysteine extraction in the normal human kidney. METHODS We measured plasma total (free and protein-bound) and free homocysteine (tHcy and fHcy, respectively) in arterial and renal venous blood sampled from the aorta and right-side renal vein during cardiac catheterization in 20 fasting patients with normal renal function. Renal homocysteine extraction was calculated as the arteriovenous difference divided by the arterial levels times 100%. RESULTS No significant renal extraction was demonstrated either for tHcy: 0.9% (SD 5.8; 95% CI -1.8 to +3.6) or for fHcy: -0.2% (11.0; -5.4 to +4.9). CONCLUSIONS We conclude that no significant net renal uptake of homocysteine occurs in fasting humans with normal renal function. The loss of such uptake, therefore, cannot cause hyperhomocysteinemia in patients with renal failure.
We report on a patient treated with hemoperfusion-hemodialysis (HP-HD) for severe paraquat poisoning. This procedure was adopted since the combination of adsorption and dialysis may improve overall drug removal. On admission blood paraquat was 15.8 micrograms/ml. He received conventional treatment and combined HP-HD which started within 3 hours after ingestion of the chemical and lasted 5 hours. Blood samples were obtained during and after HP-HD. The samples during HP-HD were taken before the charcoal column, between the charcoal column and the artificial kidney and after the artificial kidney. Blood clearances of paraquat were 116 +/- 32 ml/min (n=6) for the charcoal column (HP), 90 +/- 54 ml/min (n=6) for the artificial kidney (HD) and 151 +/- 37 ml/min (n=6) for the combined systems (HP-HD). After HP-HD a limited rebound of blood paraquat level was seen. One day after admission renal and hepatic failure had developed, and the patient died after 5 days. Tissue paraquat levels (microgram/g wet tissue) were: skeletal muscle 9.4, pancreas 6.0, prostate 5.6, thyroid 4.2, lungs 4.0, bone marrow 4.0, kidney 3.1, spleen 2.9, adrenal 2.9, heart 2.8, liver 2.3, stomach and testis below 1.0. Measurements of blood levels demonstrated the efficient clearances of paraquat with HP-HD from the central (plasma) compartment. However, the present results confirmed those previously reported which suggest that the efficiency of short HP-HD in treating severe paraquat poisoning is questionable since paraquat levels in the peripheral (tissue) compartment remain elevated.