Preventing progression in IgA nephropathy: a managed care focus on emerging therapies.

Immunoglobulin A nephropathy (IgAN) is an autoimmune disease that is the most common cause of glomerulonephritis. In IgAN, the glomeruli are impaired by deposits of IgA-complexes in the kidney, which leads to the progression of chronic kidney disease, often resulting in end-stage renal disease requiring dialysis or kidney transplantation. This progression is associated with impaired health-related quality of life and a significant economic burden. Better overall patient outcomes have been seen in patients who are diagnosed and receive treatment earlier in the disease process. Supportive therapy is the mainstay of treatment, but there have also been recent advances with targeted therapies that may provide additional therapeutic options to meet treatment goals. Managed care professionals are well positioned to design clinical programs and pathways to promote earlier diagnosis, better efficacy and safety monitoring, and timely access to targeted therapies to slow progression, reduce kidney damage, and delay or prevent end-stage renal disease.

NSAID-avoidance education in community pharmacies for patients at high risk for acute kidney injury, upstate New York, 2011.

INTRODUCTION: Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently associated with community-acquired acute kidney injury (AKI), a strong risk factor for development and progression of chronic kidney disease. Using access to prescription medication profiles, pharmacists can identify patients at high risk for NSAID-induced AKI. The primary objective of this analysis was to evaluate the effectiveness of a community pharmacy-based patient education program on patient knowledge of NSAID-associated renal safety concerns. METHODS: Patients receiving prescription medications for hypertension or diabetes mellitus were invited to participate in an educational program on the risks of NSAID use. A patient knowledge questionnaire (PKQ) consisting of 5 questions scored from 1 to 5 was completed before and after the intervention. Information was collected on age, race, sex, and frequency of NSAID use. RESULTS: A total of 152 participants (60% women) completed both the pre- and post-intervention questionnaire; average age was 54.6 (standard deviation [SD], 17.5). Mean pre-intervention PKQ score was 3.3 (SD, 1.4), and post-intervention score was 4.6 (SD, 0.9) (P = .002). Participants rated program usefulness (1 = not useful to 5 = extremely useful) as 4.2 (SD, 1.0). In addition, 48% reported current NSAID use and 67% reported that the program encouraged them to limit their use. CONCLUSION: NSAID use was common among patients at high risk for AKI. A brief educational intervention in a community pharmacy improved patient knowledge on NSAID-associated risks. Pharmacists practicing in the community can partner with primary care providers in the medical home model to educate patients at risk for AKI.

Determination of vancomycin and gentamicin clearance in an in vitro, closed loop dialysis system.

BACKGROUND: The purpose of this study was to evaluate the feasibility of utilizing an in-vitro, closed loop hemodialysis system as a method to assess drug clearance. Secondarily, this study tested the influence of variables (blood flow rate, dialysate flow rate, and type of filter) in the hemodialysis procedure on the clearance of vancomycin and gentamicin. METHODS: An in-vitro, closed loop hemodialysis system was constructed. The vancomycin (30 mg/L) and gentamicin (25 mg/L) were added to a simulated blood system (SBS). Four conditions (C1-C4) were tested by defining the filter (Polyflux 170H or F180) and the blood and dialysate flow rates (BFR and DFR). All hemodialysis sessions were 3 hours in length and each condition was completed in duplicate. Dialysate effluent was collected in a 50 gallon polyethylene drum. Samples were collected (in duplicate) from the SBS and the dialysate effluent at baseline and at the end of the hemodialysis session. Samples were analyzed for vancomycin and gentamicin with an ultrahigh performance liquid chromatography/tandem mass spectrometry method. RESULTS: A total of eight 3-hour hemodialysis sessions were conducted. For all tested conditions (C1-C4), vancomycin was undetectable in the SBS at the end of dialysis. However, total vancomycin recovery in the dialysis effluent was 85±18%, suggesting that up to 15% may have adsorbed to the dialysis filter or tubing. Gentamicin clearance from SBS was >98% in all tested conditions. Average gentamicin recovery in the dialysate effluent was 99±15%. CONCLUSION: Both vancomycin and gentamicin were readily removed by high-flux hemodialysis under all conditions studied. No significant differences in drug clearance were observed between conditions used in this in vitro study. The clinical implications of changing these hemodialysis parameters are unknown.

Evaluation of the pharmacodynamic profile of commonly used intravenous vancomycin dosing schemes in patients on automated peritoneal dialysis.

OBJECTIVES: The intent of this study was to evaluate the appropriateness of commonly used intravenous (iv) vancomycin dosing schemes in patients on automated peritoneal dialysis (APD) using population pharmacokinetic (PK) modelling and Monte Carlo simulation. METHODS: Data from a single-dose PK study of 10 non-infected APD patients ≥18 years old were analysed. Patients received iv vancomycin (15 mg/kg) followed by three cycler-assisted APD dwells over 8 h, followed by two 8 h dwells. Serum and dialysate samples were collected over the entire 24 h. A three-compartment model was fitted to the data with BigNPAG. Monte Carlo simulation was used to determine the probability of achieving an AUC/MIC ratio of >400 in both the serum and the peritoneal cavity for a variety of iv vancomycin dosing schemes (1-2 g every 24-48 h). RESULTS: In the probability of target attainment (PTA) analyses, only 2 g of iv vancomycin every 24 h conferred >90% probability of achieving an AUC/MIC ratio of >400 for MIC values <2 mg/L in the serum. However, this dosing regimen resulted in average trough concentrations >20 mg/L. In the peritoneal cavity, no regimen yielded PTA ≥90% for MIC values ≥0.5 mg/L. CONCLUSIONS: Although expert guidelines suggest iv vancomycin may be an acceptable empirical therapy for patients on APD with infection, these analyses indicate that iv vancomycin may not be effective for peritonitis but may be a viable option for non-peritoneal infections with MIC values ≤1 mg/L.

Reevaluation of ceftazidime dosing recommendations in patients on continuous ambulatory peritoneal dialysis.

While intraperitoneal (i.p.) ceftazidime is commonly used to treat continuous ambulatory peritoneal dialysis (CAPD)-related infections, the ability of i.p. regimens to achieve critical pharmacodynamic targets in both blood and dialysate has not been reported. To understand the pharmacodynamic profile of ceftazidime during CAPD, data were obtained from a single-dose pharmacokinetic (PK) i.p. ceftazidime study that included 10 CAPD patients who received i.p. ceftazidime at 15 mg/kg of body weight. The probability of target attainment (concentrations maintained above the MIC for >60% of the dosing interval [60% T > MIC]) was determined for six simulated regimens. A 3-compartment model with each dialysis dwell modeled as a separate differential equation was fit to ceftazidime concentrations using BigNPAG. Embedded with the final PK model, serum and dialysate concentration-time profiles of ceftazidime at 1, 1.5, and 2 g i.p. every 24 h (q24h) to q48h were simulated using ADAPT 5. The mean population pharmacokinetic parameters were as follows: apparent volume of the central compartment (Vc), 7.57 liter; apparent volume of the peritoneal cavity (Vpd), 2.44 liter; clearance from the central compartment (CL), 0.379 liter/h; intercompartmental transfer rate constants (first order) between the central and peripheral compartments (k12 and k21), 4.66 and 4.88 h(-1), respectively; and intercompartmental transfer rate constants (first order) between the central and peritoneal compartments (k13 and k31), 0.111 and 0.227 h(-1), respectively. In serum, the probability of target attainment for MICs of ≤8 mg/liter exceeded 90% for 1.5 to 2 g i.p. q24h to q48h. However, no tested regimen provided adequate dialysate exposure at MICs of ≥8 mg/liter on day 1 without the use of a 3-g loading dose (post hoc analysis). On day 2, 1.5 to 2 g i.p. q24h or 2 g i.p. q48h provided adequate exposure in the peritoneal cavity. These results should be validated in the presence of infection. Ceftazidime i.p. at 1.5 or 2 g q24h to q48h is recommended for nonperitoneal infections. For peritonitis, a 3-g load with maintenance dosing of 1 to 2 g i.p. q24h or 2 g i.p. q48h is recommended.

A Case of Nephrotic Syndrome With Minimal-Change Disease and Waldenstrom's Macroglobulinemia.

Kidney disease is a rare complication of Waldenstrom's macroglobulinemia. We report a case of nephrotic syndrome and minimal change disease in a patient with biopsy proven Waldenstrom's macroglobulinemia. The patient presented with over 12 grams of proteinuria and was successfully treated with oral prednisone over the course of 4 weeks. Repeat serum protein electrophoresis as well as serum immunoelectrophoresis revealed no paraproteins, urine analysis was negative for protein or blood by dipstick and spot urine protein was 9 mg/dL with creatinine of 101 mg/dL at time of last office visit. This case illustrates the successful treatment with corticosteroids alone with prolonged complete remission.

Daptomycin pharmacokinetics and pharmacodynamics in a pooled sample of patients receiving thrice-weekly hemodialysis.

While the pharmacokinetic (PK) properties of daptomycin in hemodialysis (HD) patients have been evaluated previously by three groups, resultant dosing recommendations have varied. To address this clinical conundrum, this study combined concentration-time data from these PK evaluations and derived uniform dosing recommendations among patients on HD receiving daptomycin. A two-compartment model with separate HD and non-HD clearance terms was fit to the PK data from these studies by using BigNPAG. Embedded with PK parameters from the population PK analysis, 5,000-subject Monte Carlo simulations (MCS) were performed to identify HD dosing schemes that provided efficacy (cumulative and daily area under the concentration-time curve [AUC] values) and toxicity (trough concentrations of ≥ 24.3 mg/liter) profiles comparable to those from simulations employing the daptomycin PK model derived from the Staphylococcus aureus bacteremia-infective endocarditis (SAB-IE) study. Separate HD dosing schemes were sought for the two weekly interdialytic periods (48 and 72 h). For the 48-h interdialytic period, intra- and post-HD dosing provided the most isometric cumulative and daily AUCs. For the 72-h interdialytic period, all HD dosing schemes provided noncumulative AUC values from 48 to 72 h (AUC(48-72)) that were <50% of the SAB-IE AUC(48-72) values. Increasing the parent dose by 50% intra- or post-HD provided comparable AUC(48-72) values, while maintaining acceptable trough concentration (C(min)) values. When efficacy and toxicity profiles were evaluated for each individual study, higher probabilities for C(min) reaching ≥ 24.3 mg/liter were observed in one of the three studies. Given the high probability of C(min) being ≥ 24.3 mg/liter in one of the three studies, more intensive creatine phosphokinase (CPK) monitoring may be warranted in HD patients receiving daptomycin.

Ertapenem pharmacokinetics and pharmacodynamics during continuous ambulatory peritoneal dialysis.

Scant data exist for the pharmacokinetics (PK) of ertapenem in patients on continuous ambulatory peritoneal dialysis (CAPD). The goals of this study were to characterize the PK profile of ertapenem during CAPD, determine the extent of ertapenem penetration into the peritoneal cavity, and quantify the probability of the target attainment (PTA) profile in the serum and peritoneal cavity. A single-dose PK study was conducted in seven patients on CAPD. Population PK modeling and Monte Carlo simulation determined the probability that ertapenem at 500 mg intravenously (i.v.) every 24 h (q24h) would achieve concentrations in excess of the MIC for 40% of the dosing interval (40% T>MIC, where T is time) in the serum and peritoneal cavity. Monte Carlo simulation was also used to calculate the peritoneal cavity/serum mean and median penetration ratios by estimating the area under the concentration-time curve in the peritoneal cavity and serum (AUC(Peritoneal) and AUC(Serum), respectively) from zero to infinity after a single simulated dose. The population mean (± standard deviation [SD]) values for the apparent volume in the central compartment, clearance, and apparent volume in the peritoneal cavity were 2.78 (0.62) liters, 0.24 (0.07) liters/hr, and 5.81 (2.05) liters, respectively. The mean (SD) AUC(Peritoneal)/AUC(Serum) ratio was 1.039 (0.861), and the median penetration ratio was 0.801 (interquartile range, 0.486 to 1.317). In both the serum and peritoneal cavity, ertapenem at 500 mg i.v. q24h was very likely (>90%) to achieve the pharmacodynamic target for MICs of ≤2 mg/liter. The simulations suggest that 500 mg of ertapenem i.v. q24h is very likely to achieve the exposure target associated with clinical efficacy in both the serum and peritoneal cavity against the range of MIC values deemed susceptible by the Clinical and Laboratory Standards Institute.

Drug dosing consideration in patients with acute and chronic kidney disease-a clinical update from Kidney Disease: Improving Global Outcomes (KDIGO).

Drug dosage adjustment for patients with acute or chronic kidney disease is an accepted standard of practice. The challenge is how to accurately estimate a patient's kidney function in both acute and chronic kidney disease and determine the influence of renal replacement therapies on drug disposition. Kidney Disease: Improving Global Outcomes (KDIGO) held a conference to investigate these issues and propose recommendations for practitioners, researchers, and those involved in the drug development and regulatory arenas. The conference attendees discussed the major challenges facing drug dosage adjustment for patients with kidney disease. In particular, although glomerular filtration rate is the metric used to guide dose adjustment, kidney disease does affect nonrenal clearances, and this is not adequately considered in most pharmacokinetic studies. There are also inadequate studies in patients receiving all forms of renal replacement therapy and in the pediatric population. The conference generated 37 recommendations for clinical practice, 32 recommendations for future research directions, and 24 recommendations for regulatory agencies (US Food and Drug Administration and European Medicines Agency) to enhance the quality of pharmacokinetic and pharmacodynamic information available to clinicians. The KDIGO Conference highlighted the gaps and focused on crafting paths to the future that will stimulate research and improve the global outcomes of patients with acute and chronic kidney disease.

Pharmacokinetics and pharmacodynamics of intravenous daptomycin during continuous ambulatory peritoneal dialysis.

BACKGROUND AND OBJECTIVES: This study sought to (1) characterize the pharmacokinetic (PK) profile of intravenous (i.v.) daptomycin among patients receiving continuous ambulatory peritoneal dialysis (CAPD); (2) identify optimal i.v. CAPD dosing schemes; and (3) determine extent of daptomycin penetration into the peritoneal space after i.v. administration. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A PK study was conducted among eight CAPD patients. Population PK modeling and Monte Carlo simulation (MCS) were used to identify CAPD dosing schemes providing efficacy and toxicity plasma profiles comparable with those obtained from MCS using the daptomycin population PK model derived from patients in the Staphylococcus aureus bacteremia-infective endocarditis (SAB-IE) study. The primary efficacy exposure target was the area under the curve (AUC). For toxicity, the goal was to identify CAPD dosing schemes that minimized plasma trough concentrations in excess of 24.3 mg/L. Finally, peritoneal cavity penetration was determined. RESULTS: Administration of i.v. daptomycin 4 or 6 mg/kg, depending on indication, every 48 h was identified as the optimal CAPD dosing scheme. This regimen provided cumulative (AUC(0-48)) and daily partitioned (AUC(0-24 h) and AUC(24-48 h)) plasma AUC values similar to the SAB-IE or "typical patient" simulations. In addition, the proportion of patients likely to experience an elevated trough concentration in excess of 24.3 mg/L was similar between every 48 h CAPD dosing and the referent group. Penetration into the peritoneal cavity was 6% of plasma. CONCLUSIONS: Daptomycin 4 or 6 mg/kg, on the basis of indication, i.v. every 48 h was found to be the optimal i.v. CAPD dosing scheme.

Quantifying home medication regimen changes and quality of life in patients receiving nocturnal home hemodialysis.

Medication regimen simplification may improve adherence in end-stage kidney disease. The effect of nocturnal home hemodialysis (NHHD) on medication burden is unknown. A retrospective pilot study of NHHD patients was conducted. Medication information was collected at baseline, NHHD start, and at 3, 6, 12, 18, and 24 months. SF-36 scores were collected at baseline, 6, 12, and 24 months. The number of medications, pill burden, and number of administrations per day were determined. Medication Regimen Complexity Index was used at each time point as a comparator. Medications for anemia, mineral and bone disorders (MBD), cardiovascular (CV) disease, infection, and vitamins were analyzed for number of medications and pill burden. Thirty-five patients were included. Patients used 10.5 ± 4.4 medications at baseline and 11.8 ± 4.7 at the end of the study (P=NS). Regarding the number of medications, anemia medications, anti-infectives, and vitamins increased; MBD and CV medications decreased by the end of the study. Total pill burden did not change over 24 months, nor did anemia pill burden. Mineral bone disorder and CV pill burden decreased, and vitamins and anti-infective pill burden increased. Daily medication administration times decreased significantly from 5.0 ± 1.5 to 3.6 ± 1.5 by 24 months. Switching to NHHD was associated with a significant increase in Medication Regimen Complexity Index at 24 months (P<0.05). SF-36 scores increased significantly once patients began on NHHD. No measure of medication regimen complexity was correlated with the SF-36 score. Medication burden changes over time after starting NHHD. It is unknown what effect NHHD has on adherence or medication costs, and warrants further study in a prospective comparative investigation.

Use of pharmacokinetic and pharmacodynamic principles to determine optimal administration of daptomycin in patients receiving standardized thrice-weekly hemodialysis.

This study identified optimal daptomycin dosing for patients receiving thrice-weekly hemodialysis (HD). Twelve adult patients on HD received daptomycin at 6 mg/kg of body weight intravenously (i.v.) one time; plasma and dialysate samples were collected over 3 days. A 2-compartment model with separate HD and non-HD clearance terms was fit to the data. A series of 9,999-subject Monte Carlo simulations (MCS) was performed to identify HD dosing schemes providing efficacy and toxicity profiles comparable to those obtained for MCS employing the daptomycin population pharmacokinetic (PK) model derived from patients in the Staphylococcus aureus bacteremia-infective endocarditis (SAB-IE) study. For efficacy, we selected the HD dosing scheme which generated an area-under-the-curve (AUC) exposure profile comparable to that for the SAB-IE population model. For toxicity, we selected HD dosing schemes that minimized trough concentrations of ≥ 24.3 mg/liter. Separate HD dosing schemes were developed for each FDA-approved regimen and for two weekly interdialytic periods (48 and 72 h). Administration of the same parent daptomycin dose intra-HD and post-HD resulted in AUC, maximum concentration of drug in serum (C(max)), and C(min) values most comparable to those for SAB-IE simulations for the 48-hour interdialytic period. In contrast, all candidate HD dosing schemes provided AUC(48-72) values that were at least 50% lower than the SAB-IE AUC(48-72) values. Increasing the parent dose by 50% provided more comparable AUC(48-72) values while maintaining acceptable C(min) values. Administration of the daptomycin parent dose intra-HD or post-HD was optimal for the 48-h interdialytic period. For the 72-h interdialytic period, clinicians should consider increasing the dose by 50% to achieve more comparable AUC(48-72) values.

Update on clinical practice recommendations and new therapeutic modalities for treating anemia in patients with chronic kidney disease.

PURPOSE: The National Kidney Foundation (NKF) clinical practice recommendations for treating anemia in chronic kidney disease (CKD) and the dosing, route and frequency of administration, efficacy, and safety of currently available and investigational drug therapies for anemia in patients with CKD, including the erythropoietin-stimulating agents (ESAs) iron replacement, and adjuvants, are described. SUMMARY: The NKF recommendations for ESA use are general and include dosing based on the measured and target hemoglobin concentrations, the rate of increase in hemoglobin, and clinical circumstances, with the route and frequency of administration determined by the CKD stage, treatment setting, efficacy, and ESA class. A serum ferritin concentration of 100-500 ng/mL is the target during oral and intravenous (i.v.) iron therapy for predialysis and peritoneal dialysis patients, but use of the i.v. route of administration and a target serum ferritin concentration of 200-500 ng/mL is recommended for hemodialysis patients by NKF. Iron deficiency and inflammation are possible causes of inadequate response to ESAs. The safety profile of epoetin alfa and darbepoetin alfa are similar, but the longer half-life of darbepoetin alfa permits administration on a once-monthly basis in patients with CKD and anemia. Extended dosing of CERA also appears safe and effective in dialysis patients with CKD. Several investigational anemia therapies with a variety of mechanisms of action are in development. CONCLUSION: Efforts by the NKF to update their clinical practice recommendations provide clinicians with insight into the optimal therapeutic approach to treating anemia in patients with CKD. Clinical research has resulted in the development of new therapeutic modalities to improve outcomes in patients with CKD and anemia.

Open-label pilot study comparing quantitative ultrasound and dual-energy X-ray absorptiometry to assess corticosteroid-induced osteoporosis in patients with chronic kidney disease.

BACKGROUND: Patients with chronic kidney disease (CKD) might be at high risk for bone disease. Decreased functional kidney mass contributes to renal osteodystrophy, which might be exacerbated by certain drug therapies. Long-term (> or = 6 months) corticosteroid treatment is commonly prescribed in patients with glomerular disease, possibly causing bone loss both indirectly and directly, putting the patient at increased risk for fracture. The dual-energy x-ray absorptiometry (DXA) is the current "gold standard" for measuring osteoporosis-related fractures and works by passing ultrasound waves through bone to determine the structural anisotropy in the heel. OBJECTIVE: This pilot study was designed to determine whether there is a correlation between DXA and quantitative ultrasound (QUS) in detecting corticosteroid-induced osteoporosis. METHODS: This open-label pilot study was conducted at the Medical Center Nephrology Clinic, Albany Medical College, Albany, New York. Female patients aged > or = 18 years with a diagnosis of CKD and/or a history of kidney transplantation and who were receiving long-term corticosteroid treatment were enrolled. Each patient served as her own control and underwent DXA of the hip and spine (DXA-hip and DXA-spine, respectively) and QUS of the dominant and nondominant heels (QUS-dominant and QUS-nondominant, respectively), within 1 week so that conditions were similar in each patient. RESULTS: Eight patients were included in the study (mean [SD] age, 50.2 [11.2] years). A positive correlation was found between DXA-hip and QUS-nondominant (r2=0.76; P=0.009); however, no correlation was found with DXA-spine. Similarly, a positive correlation was found between DXA-hip and QUS-dominant (r2=0.75; P=0.009), but no correlation with DXA-spine was found (r2=0.22). CONCLUSION: In this small, selected population, QUS showed a fair correlation with DXA-hip but no correlation with DXA-spine. Further studies are needed to determine the effectiveness in other populations.

Comparison of the Achilles Express ultrasonometer with central dual-energy X-ray absorptiometry.

BACKGROUND: Quantitative ultrasound (QUS) devices provide portable, easy-to-operate, low-cost options for point-of-care screening of bone mineral density (BMD). Community pharmacists should be aware of the precision, sensitivity, and specificity of these devices prior to their purchase. OBJECTIVE: To determine the precision, sensitivity, and specificity of the Achilles Express ultrasonometer compared with central dual-energy X-ray absorptiometry (cDXA) as well as its utility as a bone density screening device in the community pharmacy setting. METHODS: A prospective study in a community pharmacy and outpatient ambulatory clinic was conducted with 2 groups of white women. Group 1 participants were 25-35 years of age (young, healthy), and those in Group 2 were 45 years of age or older (postmenopausal). BMD assessments of the spine and the nondominant wrist and hip were performed using cDXA. Assessments of the heel were performed using the Achilles Express, a QUS device. The main outcome measures were correlation of t-scores between cDXA and QUS measurements using the Pearson correlation test. RESULTS: Twenty-two (30 +/- 4 years of age) and 31 (55 +/- 17 years of age) women were enrolled into Groups 1 and 2, respectively. Significant correlations between QUS and hip and spine cDXA t-scores were found in both groups. Correlation coefficients for QUS versus hip cDXA were 0.51 (95% CI 0.11 to 0.77) and 0.70 (95% CI 0.46 to 0.85) in Groups 1 and 2, respectively. Correlation coefficients for the QUS versus spine cDXA were 0.64 (95% CI 0.31 to 0.84) and 0.60 (95% CI 0.31 to 0.79) in Groups 1 and 2, respectively. The QUS device has a sensitivity level of 88% and specificity of 71% to detect a hip cDXA t-score of less than-1. CONCLUSIONS: The Achilles Express ultrasonometer is a reasonable screening tool to detect low BMD in postmenopausal women.

Caring for patients with chronic kidney disease: a joint opinion of the ambulatory care and the nephrology practice and research networks of the American College of Clinical Pharmacy.

An increasing number of patients are developing chronic kidney disease (CKD). Appropriate care for patients with CKD must occur in the earliest stages, preferably before CKD progresses to more severe stages. Therefore, recognition and treatment of CKD and its associated complications must occur in primary care settings. Patients with CKD often have comorbid conditions such as diabetes mellitus, hypertension, and dyslipidemia, creating specific considerations when treating these diseases. Also, these patients have CKD-related conditions, including anemia and renal osteodystrophy, that are not traditionally evaluated and monitored by the primary care practitioner. Collectively, many opportunities exist for pharmacists who practice in the primary care setting to improve the care of patients with CKD.

Comparison of natural product use between primary care and nephrology patients.

BACKGROUND: The use of natural products is increasing, but healthcare professionals may underestimate the use of these agents by patients. It is unknown whether natural product use differs between primary care and specialty clinic patients, such as those in a nephrology clinic. OBJECTIVE: To compare patterns of natural product use between primary care and nephrology clinic patients. METHODS: One thousand adult patients from each clinic were randomly mailed an anonymous questionnaire to determine current and past use of natural products. RESULTS: A total of 491 surveys were returned, for an overall response rate of 26% (25% primary care; 28% nephrology clinic). Current use of natural products was similar between the primary care and nephrology groups (34% vs 29%, respectively; p = NS). Primary care patients were more likely to have taken a natural product in the past (57% vs 45%; p < 0.05); Echinacea was the most common product taken by those patients (26%). Green tea was the most common natural product taken by nephrology clinic patients (18%). More primary care patients took Echinacea compared with nephrology clinic patients (26% vs 12%; p < 0.01). Adverse reactions led to discontinuation of the natural product in 7% of respondents. CONCLUSIONS: Active use of natural products was similar between the survey respondents. Documentation and monitoring of natural product use by healthcare professionals working with primary care and nephrology clinic patients are recommended.

Determination of iron sucrose (Venofer) or iron dextran (DexFerrum) removal by hemodialysis: an in-vitro study.

BACKGROUND: Intravenous iron is typically administered during the hemodialysis (HD) procedure. HD patients may be prescribed high-flux (HF) or high-efficiency (HE) dialysis membranes. The extent of iron sucrose and iron dextran removal by HD using HF or HE membranes and by ultrafiltration rate (UFR) is unknown. METHODS: Two in vitro HD systems were designed and constructed to determine the dialyzabiltiy of iron from a simulated blood system (SBS) containing 100 mg iron sucrose or iron dextran (system A) or 1000 mg iron sucrose (system B). Both in vitro systems utilized a 6-L closed-loop SBS system that was subject to 4 different HD conditions conducted over 4 hours: HE membrane + 0 ml/hr UFR; HE membrane + 500 ml/hr UFR; HF membrane + 0 ml/hr UFR; HF membrane + 500 ml/hr UFR. Blood flow and dialysate flow rates were 500 ml/min and 800 ml/min, respectively. The dialysate compartment was a 192-L open system for system A and a 6-L closed-loop system for system B. Samples from the SBS and dialysate compartments were taken at various time points and iron elimination rate and HD clearance was determined. Iron removal from the SBS > 15% was considered clinically significant. RESULTS: The greatest percentage removal from the SBS was 13.5% and -0.03% utilizing system A and B, respectively. Iron sucrose and iron dextran dialysate concentration was below the lower limits of assay (< 2 ppm) for system A. Dialysate recovery of iron was negligible: 0-5.4 mg system A and 5.47-23.59 mg for system B. Dialyzer type or UFR did not affect iron removal. CONCLUSION: HF or HE dialysis membranes do not remove clinically significant amounts of iron sucrose or dextran formulations over a 4-hour HD session. This effect remained constant even controlling for UFR up to 500 ml/hour. Therefore, iron sucrose and iron dextran are not dialyzed by HE or HF dialysis membranes irrespective of UFR.