Performance of estimated glomerular filtration rate prediction equations in preeclamptic patients

Accurate estimation of the glomerular filtration rate (GFR) in patients with preeclampsia requires the collection of a 24-hour urine and can have important therapeutic and diagnostic implications. This procedure is often difficult or impossible to accomplish in this patient group. In this study, the Cockcroft-Gault, the Modification of Diet in Renal Disease (MDRD), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas were evaluated for their accuracy in determining GFR in the setting of preeclampsia. The estimated GFRs calculated from the above formulas were compared with the creatinine clearance values obtained from a 24-hour urine collections in 543 preeclamptic patients recruited from several large hospitals. Additionally, a set of new equations, preeclampsia GFR (PGFR), based on ethnicity, was created. The Cockcroft-Gault, MDRD, and CKD-EPI formulas were inaccurate in predicting GFR and both were significantly less accurate than PGFR. The latter formula provided an estimated GFR that was much closer to the creatinine clearance. Current GFR estimation equations based on serum creatinine values in nonpregnant patients are not reliable measures of renal function in patients with preeclampsia. The use of a new formula (PGFR) is recommended.

The treatment of preeclampsia in a rat model employing Digibind

Preeclampsia (PE) is a disorder that results in significant fetomaternal morbidity and mortality with yet no definitive pharmacological intervention. It involves the development of de novo hypertension and proteinuria after 20 weeks of pregnancy. All too often, intrauterine growth restriction (IUGR) occurs. Evidence has accrued that implicates the cardiac glycosides (the cardenolides and the bufadienolides) as potentially involved in the pathophysiology of PE. These compounds act by inhibiting Na(+)/K(+) ATPase. Digibind (digoxin immune Fab) antagonizes this action of the cardenolides. It also has cross-reactivity against the bufadienolides, including marinobufagenin. This study investigated the effects of Digibind in a rat model of PE. We induced a syndrome in rats, which includes many of the phenotypic characteristics of human PE. Digibind, in escalating doses, was given on days 10 to 20 of pregnancy. Digibind produced significant lowering of the blood pressure and reduced proteinuria in our rat model of PE. However, it also did not avert IUGR. In view of these findings, in our experimental model of human PE, further studies in the quest for effective treatment of PE need to focus on pharmaceuticals that can remedy the syndrome without compromising the fetus.

Estimation of glomerular filtration rate in preeclamptic patients

Accurate estimation of the glomerular filtration rate (GFR) in patients with preeclampsia is often difficult or impossible to accomplish. In this study, the Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD), and MDRD2 formulas were evaluated for their accuracy in determining GFR in the setting of preeclampsia. The estimated GFR calculated from these formulas was compared with the creatinine clearance values obtained from a 24-hour urine collection in 209 preeclamptic patients recruited from five large hospitals. Additionally, a set of new equations that more accurately estimate GFR in preeclamptic patients based on ethnicity, preeclampsia GFR (PGFR), was created. Both the CG and MDRD formulas were inaccurate in predicting GFR in preeclamptic patients, and both were significantly less accurate than PGFR. In conclusion, current GFR estimation equations based on serum creatinine values in nonpregnant patients are not reliable measures of renal function in patients with preeclampsia. The use of a new (PGFR) formula is recommended.

Effects of the selective cyclooxygenase-2 inhibitor analgesic celecoxib on renal carbonic anhydrase enzyme activity: a randomized, controlled trial

Rofecoxib and celecoxib were the first cyclooxygenase-2 (COX-2)-specific inhibitors to be marketed as effective anti inflammatory agents. The results of several recent trials and a meta analysis of currently available studies all demonstrate a greater incidence of increased blood pressure, edema, and cardiovascular events in subjects treated with rofecoxib compared with celecoxib. As an approach to the assessment of molecular mechanisms that may contribute to these cardiorenal differences, this study investigated the inhibitory effects of celecoxib on renal carbonic anhydrase enzyme activity in human hypertensive subjects because in vitro enzyme studies demonstrate such an effect. Ten subjects with stable, treated hypertension were randomized to 1 of 3 treatment sequences, which included, in differing order, 200 mg celecoxib twice a day, 250 mg acetazolamide twice a day, or placebo twice a day. Whereas acetazolamide caused a bicarbonate diuresis and a hyperchloremic metabolic acidosis, celecoxib appeared to have no detectable effect on renal carbonic anhydrase or acid-base homeostasis. Thus, in this short-term study of human subjects, therapeutic doses of celecoxib did not appear to have a clinically significant inhibitory action on renal carbonic anhydrase.

Guidelines for the Reporting of Renal Artery Revascularization in Clinical Trials

Although the treatment of atherosclerotic renal artery stenosis with use of percutaneous angioplasty, stent placement, and surgical revascularization has gained widespread use, there exist few prospective randomized controlled trials (RCTs) comparing these techniques to each other or against the standard of medical management alone. To facilitate this process as well as help answer many important questions regarding the appropriate application of renal revascularization, well-designed and rigorously conducted trials are needed. These trials must have clearly defined goals and must be sufficiently sized and performed so as to withstand intensive outcomes assessment. Toward this end, this document provides guidelines and definitions for the design, conduct, evaluation, and reporting of renal artery revascularization RCTs. In addition, areas of critically necessary renal artery revascularization investigation are identified. It is hoped that this information will be valuable to the investigator wishing to conduct research in this important area.

Guidelines for the reporting of renal artery revascularization in clinical trials

Although the treatment of atherosclerotic renal artery stenosis with use of percutaneous angioplasty, stent placement, and surgical revascularization has gained widespread use, there exist few prospective randomized controlled trials (RCTs) comparing these techniques to each other or against the standard of medical management alone. To facilitate this process as well as help answer many important questions regarding the appropriate application of renal revascularization, well-designed and rigorously conducted trials are needed. These trials must have clearly defined goals and must be sufficiently sized and performed so as to withstand intensive outcomes assessment. Toward this end, this document provides guidelines and definitions for the design, conduct, evaluation, and reporting of renal artery revascularization RCTs. In addition, areas of critically necessary renal artery revascularization investigation are identified. It is hoped that this information will be valuable to the investigator wishing to conduct research in this important area.

Fractures and vertebral bone mineral density in patients with renal osteodystrophy

We investigated the relationship of CT determined vertebral bone mineral density (BMD), type of renal osteodystrophy, N terminal PTH levels and fracture history in 31 dialysis patients. BMD for patients with bone biopsy documented osteitis fibrosa was 1.6 standard deviation (SD) above the normal value for age and sex matched controls, while those patients with low turnover osteodystrophy had a mean BMD 1.2 SD below normal (p less than 0.0001). Three patients with osteitis fibrosa who had previously been treated with prednisone had a low BMD (1.8 SD below normal, different than O, p = 0.0015). There was no correlation between BMD and time on dialysis (r = 0.1). An N terminal PTH level greater than 150 pg/ml was a sensitive (94%) and specific (100%) method of separating those patients with osteitis fibrosa from those with low turnover osteodystrophy, while BMD was much less useful in this differentiation. A low BMD was not predictive of fracture history but the type of renal osteodystrophy was. Patients with low turnover osteodystrophy had a fracture rate of 0.2 fractures/dialysis year in comparison to those with osteitis fibrosis who had 0.1 fractures/dialysis year. Patients with the former bone disease fractured mainly axial rather than appendicular bones in contrast to those patients with osteitis fibrosa. In conclusion we found that patients with osteitis fibrosa had increased BMD compared to normal while those with low turnover osteodystrophy had decreased BMD, but that the N terminal PTH level was a better predictor of the type of bone disease present than was BMD.