The failure of glomerular filtration rate estimating equations among obese population.

BackgroundObesity is a major public health with increasing numbers of obese individuals are at risk for kidney disease. However, the validity of serum creatinine-based glomerular filtration rate (GFR) estimating equations in obese population is yet to be determined.MethodsWe evaluated the performance of the reexpressed Modification of Diet in Renal Disease (MDRD), reexpressed MDRD with Thai racial factor, Thai estimated GFR (eGFR) as well as Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations among obese patients, defined as body mass index (BMI) ≥25 kg/m2 with the reference measured GFR (mGFR) determined by 99mTc-diethylene triamine penta-acetic acid (99mTc-DTPA) plasma clearance method. Serum creatinine levels were measured using standardized enzymatic method simultaneously with GFR measurement. The statistical methods in assessing agreement for continuous data including total deviation index (TDI), concordance correlation coefficient (CCC), and coverage probability (CP) for each estimating equation were compared with the reference mGFR. Accuracy within 10% representing the percentage of estimations falling within the range of ±10% of mGFR values for all equations were also tested.ResultsA total of 240 Thai obese patients were finally recruited with mean BMI of 31.5 ± 5.8 kg/m2. In the total population, all eGFR equations underestimated the reference mGFR. The average TDI values were 55% indicating that 90% of the estimates falling within the range of -55 to +55% of the reference mGFR. The CP values averaged 0.23 and CCC scores ranged from 0.75 to 0.81, reflecting the low to moderate levels of agreement between each eGFR equation and the reference mGFR. The proportions of patients achieving accuracy 10% ranged from 23% for the reexpressed MDRD equation to 33% for the Thai eGFR formula. Among participants with BMI more than 35 kg/m2 (n = 48), the mean error of all equations was extremely wide and significantly higher for all equations compared with the lower BMI category. Also, the strength of agreement evaluated by TDI, CCC, and CP were low in the subset of patients with BMI ≥35 kg/m2.ConclusionEstimating equations generally underestimated the reference mGFR in subjects with obesity. The overall performance of GFR estimating equations demonstrated poor concordance with the reference mGFR among individuals with high BMI levels. In certain clinical settings such as decision for dialysis initiation, the direct measurements of GFR are required to establish real renal function among obese population

Intraperitoneal cefepime monotherapy versus combination therapy of cefazolin plus ceftazidime for empirical treatment of CAPD-associated peritonitis: A multicenter, open-label, noninferiority, randomized, controlled trial

Rationale & Objective: Compared to combination therapy, intraperitoneal (IP) cefepime monotherapy for continuous ambulatory peritoneal dialysis (CAPD)-associated peritonitis may provide potential benefits in lowering staff burden, shortening time-consuming antibiotic preparation, and reducing bag contamination risk. This study sought to evaluate whether cefepime monotherapy is noninferior to combination regimens. Study Design: Multicenter, open-label, noninferiority, randomized, controlled trial. Setting & Participants: Adult incident peritoneal dialysis (PD) patients with CAPD-associated peritonitis in 8 PD centers in Thailand. Interventions: Random assignment to either IP monotherapy of cefepime, 1 g/d, or IP combination of cefazolin and ceftazidime, 1 g/d, both given as continuous dosing. Outcomes: Primary end point: resolution of peritonitis at day 10 (primary treatment response). Secondary outcomes: initial response (day 5), complete cure (relapse/recurrence-free response 28 days after treatment completion), relapsing/recurrent peritonitis, and death from any cause. Noninferiority would be confirmed for the primary outcome if the lower margin of the 1-sided 95% CI was not less than −10% for difference in the primary response rate. A 2-sided 90% CI was used to demonstrate the upper or lower border of the 1-sided 95% CI. Results: There were 144 eligible patients with CAPD-associated peritonitis, of whom 70 and 74 patients were in the monotherapy and combination-therapy groups, respectively. Baseline demographic and clinical characteristics were not different between the groups. The primary response was 82.6% in the monotherapy group and 81.1% in the combination-therapy group (treatment difference, 1.5%; 90% CI, −9.1% to 12.1%; P = 0.04). There was no significant difference in the monotherapy group compared with the combination-therapy group in terms of initial response rate (65.7% vs 60.8%; treatment difference, 4.9%; 95% CI, −10.8% to 20.6%; P = 0.5) and complete cure rate (80.0% vs 80.6%; treatment difference, −0.6%; 95% CI, −13.9% to 12.8%; P = 0.7). Relapsing and recurrent peritonitis occurred in 4.6% and 4.6% of the monotherapy group and 4.2% and 5.6% of the combination-therapy group (P = 0.9 and P = 0.8, respectively). There was nominally higher all-cause mortality in the monotherapy group (7.1% vs 2.7%; treatment difference, 4.4%; 95% CI, −2.6% to 11.5%), but this difference was not statistically significant (P = 0.2). Limitation: Not double blind. Conclusions: IP cefepime monotherapy was noninferior to conventional combination therapy for resolution of CAPD-associated peritonitis at day 10 and may be a reasonable alternative first-line treatment. Funding: This study is supported by The Kidney Foundation of Thailand (R5879), Thailand; Rachadaphiseksompotch Fund (RA56/006) and Rachadaphicseksompotch Endorsement Fund (CU-GRS_61_06_30_01), Chulalongkorn University, Thailand; National Research Council of Thailand (156/2560), Thailand; and Thailand Research Foundation (IRG5780017), Thailand. Trial Registration: Registered at ClinicalTrials.gov with study number NCT02872038