Cockcroft-Gault, Modification of Diet in Renal Disease, and Chronic Kidney Disease Epidemiology Collaboration equations for estimating glomerular filtration rates in cancer patients receiving cisplatin-based chemotherapy

Comparison of the performance of currently used estimated glomerular filtration rate equations with 24-hour urine creatinine clearance: sample analysis of randomised controlled trial participants

OBJECTIVE

There are several equations for estimating the glomerular filtration rate (GFR), and each method has its limitations. We compared various estimated GFR (eGFR) equations with 24 hours urine creatinine clearance (24u-CCr).

DESIGN

Sample analysis of randomised controlled trial participants.

SETTING AND PARTICIPANTS

We compared the mean 24u-CCr values measured 2-3 times for 211 patients with eGFR values calculated using the following equations: isotope dilution mass spectrometry-Modification of Diet in Renal Disease (IDMS-MDRD) equation, Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation, equations for Koreans (KOR-IDMS-MDRD and KOR-CKD-EPI) and full age spectrum equation.

OUTCOME MEASURES

Performance of various creatinine-based eGFR equations, including those with Korean coefficients, compared with the results of the 24u-CCr.

RESULTS

IDMS-MDRD showed the best overall correlation with the 24u-CCr (R=0.949, p<0.001), and KOR-CKD-EPI showed the best agreement in terms of the intraclass correlation coefficient (ICC, 0.969, 95% CI 0.959 to 0.976, p<0.001). In subgroup analysis, IDMS-MDRD-GFR showed the highest ICCs in CKD stages 1 and 3 (ICC 0.872 in stage 1 and 0.927 in CKD stage 3, all p<0.001). KOR-CKD-EPI showed the highest ICC in CKD stage 2 (ICC 0.854, p<0.001). Overall, the accuracy of CKD-EPI (2021) was the highest at P15 (15%) and P30 (30%) (P15: 65.4 and P30: 97.6). In addition, CKD-EPI (2021) showed the highest P30 accuracy in CKD stage 1 (98.7), whereas KOR-IDMS-MDRD showed the highest P30 accuracy in CKD stages 2 and 3 (98.8 and 98.2, respectively).

CONCLUSIONS

The IDMS-MDRD equation showed the best correlation and overall good agreement with the 24u-CCr; however, the accuracy was low. The most accurate measurements were obtained using the CKD-EPI (2021) equation in CKD stage 1 and the KOR-IDMS-MDRD equation in CKD stages 2-3; nevertheless, the CKD-EPI (2021) equation showed the best overall accuracy.

TRIAL REGISTRATION NUMBER

NCT01552954.

Population Pharmacokinetics of Ganciclovir in Allogeneic Hematopoietic Stem Cell Transplant Patients

Treatment of cytomegalovirus (CMV) infection in allogeneic hematopoietic stem cell transplantation (alloHCT) patients with ganciclovir is complicated by toxicity and resistance. This study aimed to develop an intravenous ganciclovir population pharmacokinetic model for post-alloHCT patients and to determine dosing regimens likely to achieve suggested therapeutic exposure targets. We performed a prospective observational single-center pharmacokinetic study in adult alloHCT patients requiring treatment with intravenous ganciclovir for CMV viremia or disease. Samples were analyzed using a validated ultraperformance liquid chromatography method. Population pharmacokinetic analysis and Monte Carlo simulations (n = 1000) were performed using Pmetrics for R. Twenty patients aged 18 to 69 years were included in the study. A 2-compartment model with linear elimination from the central compartment and between occasion variability best described the data. Incorporating creatinine clearance (CLCR) estimated by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation and presence of continuous renal replacement therapy as covariates for ganciclovir clearance improved the model. Compared to current dosing recommendations, simulations demonstrated loading doses were required to achieve a target AUC24 of 80 to 120 mg.h/L on day 1 of induction therapy. Increased individualization of post-loading induction and maintenance doses based on CLCR is required to achieve the suggested exposures for efficacy (AUC24 >80/>40 mg.h/L for induction/maintenance) while remaining below the exposure thresholds for toxicity (AUC24 <120/<60 mg.h/L for induction/maintenance). Intravenous ganciclovir dosing in alloHCT patients can be guided by CLCR estimated by CKD-EPI. Incorporation of loading doses into induction dosing regimens should be considered for timely achievement of currently suggested exposures.

Applicability of 14 Formulas for Estimating Glomerular Filtration Rate in the Evaluation of Renal Function before and after Nephron-Sparing Surgery in Patients with Renal Tumors

To compare the applicability of 14 equations of estimating glomerular filtration rate (eGFR) before and after nephron-sparing surgery (NSS) for renal function assessment of patients with renal tumors. Preoperative and postoperative GFR is measured by emission computed tomography (ECT) with 99mTc-DTPA as an imaging agent as reference GFR (rGFR) to compare with all formulas. Spearman correlation analysis and Bland-Altman agreement analysis were used to evaluate the correlation between rGFR and eGFR1 to 14 before and after surgery. A total of 50 cases including 22 males and 28 females were included. The results of preoperative eGFR1-14 correlated with rGFR (P < 0.05). The calculation results of all estimation formulas have a significant correlation with preoperative GFR. Preoperative MDRD-I, CKD-EPI SCysC, and FAS Scr-SCysC have good consistency. The CG formula has the highest precision and FAS Scr-SCysC has the highest accuracy. A total of 30 patients followed up after surgery, and postoperative rGFR correlated with CG, CKD-EPI, FAS, and BIS formulas (P < 0.05). But postoperative rGFR has no significant correlation with MDRD and Schwartz (P > 0.05). Postoperative CKD-EPI Scr-SCysC has best consistency, and FAS Scr-SCysC has the highest accuracy and precision. Our data suggest that eGFR equations evaluated by both serum creatinine (Scr) and cystatin C (SCysC) is not necessarily better than those evaluated by one of them alone. Among all enrolled equations, FAS Scr-SCysC is the best one to evaluate postoperative GFR in patients with renal tumors.

Cancer Drug Dosing in Chronic Kidney Disease and Dialysis

Patients with malignancies have a high prevalence of kidney disease and are often treated with antineoplastic agents that undergo kidney metabolism or excretion or clearance via renal replacement therapies. Thus, the dosing of these agents, including classic chemotherapeutic drugs, targeted therapies, and immunotherapy, must take into account patients' kidney function. In this review, we will discuss the pitfalls of accurate measurement of kidney function and how kidney disease affects both pharmacodynamic and pharmacokinetic properties of drugs. Lastly, we will discuss specific agents and summarize current dosing strategies for use in patients with chronic kidney disease and end-stage kidney disease.

Potential Effects of Telbivudine Versus Entecavir on Renal Function in Patients With Chronic Hepatitis B Virus Receiving Glucocorticoids Therapy

Data remains limited about the optimal nucleos(t)ide analogue therapy for patients infected with hepatitis B virus (HBV) while treated with glucocorticoids because of kidney diseases. We aim to evaluate the safety and efficacy of long-term antiviral therapy with telbivudine (LdT) and entecavir (ETV) in this specific population. In this prospective randomized controlled study, a total of 60 patients with both kidney diseases and chronic hepatitis B were randomly divided into LdT group and ETV group. We analyzed changes in estimated glomerular filtration rate (eGFR), variation in HBV DNA, seroconversion of hepatitis B e antigen (HbeAg) and hepatitis B surface antigen (HBsAg). During the 18 month follow-up period, serum HBV DNA load was decreased significantly at 3, 6, 12, 18 months, compared to the pre-treatment value in both LdT and ETV cohorts. No patients achieved HBeAg loss-seroconversion or HBsAg loss-seroconversion with ETV therapy whilst one patient experienced HBeAg and HBsAg loss-seroconversion with LdT therapy. No significant changes in eGFR were seen in patients with ETV therapy compared to baseline. However, eGFR increased 7.43, 18.97 mL/min/1.73m² , respectively at 12 and 18 months in LdT group and the changes were significant compared to baseline. Further analysis also demonstrated that eGFR significantly improved 11.8, 23.25 mL/min/1.73m² at 12 and 18 months in LdT group for patients with impaired renal function. LdT is superior to ETV in patients with chronic hepatitis B and kidney diseases because of the renal protection it confers by increasing eGFR.