Obesity 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.
We 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.
A 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.
Estimating 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.
The objective of this study was to determine the impact of calcium sensing receptor (CASR) A990G genetic polymorphism on parathyroid hormone (PTH) lowering response to cinacalcet treatment when ...controlling for significant influencing clinical factors. This retrospective study was conducted on 135 Thai hemodialysis (HD) patients with secondary hyperparathyroidism (SHPT). CASR A990G genotypes were determined. The patients were identified as either G carriers (heterozygous or homozygous CASR 990G allele carriers) or noncarriers (homozygous CASR 990A carriers). Tested covariates were baseline PTH level (bPTH), baseline serum phosphate (bPhos), baseline serum calcium (bCa), baseline calcitriol equivalent dose (bCtriol), baseline ergocalciferol dose (bErgo), and age. The ANCOVA showed that intact PTH levels after 12 weeks of cinacalcet treatment (PTHw12) was significantly lower among G carriers compared with noncarriers after controlling for bPTH, bPhos, bCtriol, and bErgo (F(1, 127) = 15.472, p < 0.001), with the adjusted mean difference of 253.7 pg/mL. The logistic regression analysis revealed that the odds of a G carrier achieving 30% PTH reduction after 12-week cinacalcet treatment were 3.968 times greater than the odds for a noncarrier after adjusting for bPhos, bCtriol, and age. In conclusion, the CASR A990G polymorphism significantly influences cinacalcet response in HD patients with SHPT.
Hypokalemia is a common electrolyte abnormality in patients on peritoneal dialysis (PD) and has been associated with increased risks of peritonitis and death. Whether correction of hypokalemia ...improves these outcomes is unknown.
Multicenter, open-label, prospective, randomized controlled trial.
Adult (aged ≥18 years) PD patients with hypokalemia (defined as at least 3 values or an average value <3.5 mEq/L in the past 6 months). Randomization was stratified according to center and residual urine output (≤100 or >100 mL/day).
Random assignment to either protocol-based potassium supplementation (titratable dose of oral potassium chloride to maintain serum potassium of 4-5 mEq/L) or conventional potassium supplementation (reactive supplementation when serum potassium is <3.5 mEq/L) over 52 weeks. Treatment groups were compared using intention-to-treat analyses implemented using Cox proportional hazards regression.
The primary outcome was time from randomization to first peritonitis episode (any organism). Secondary outcomes were all-cause mortality, cardiovascular mortality, hospitalization, and conversion to hemodialysis.
A total of 167 patients with time-averaged serum potassium concentrations of 3.33 ± 0.28 mEq/L were enrolled from 6 PD centers: 85 were assigned to receive protocol-based treatment, and 82 were assigned to conventional treatment. The median follow-up time was 401 (IQR, 315-417) days. During the study period, serum potassium levels in the protocol-based treatment group increased to 4.36 ± 0.70 mEq/L compared with 3.57 ± 0.65 mEq/L in the group treated conventionally (mean difference, 0.66 95% CI, 0.53-0.79 mEq/L; P < 0.001). The median time to first peritonitis episode was significantly longer in the protocol-based group (223 IQR, 147-247 vs 133 IQR, 41-197 days, P = 0.03). Compared with conventional treatment, the protocol-based group had a significantly lower hazard of peritonitis (HR, 0.47 95% CI, 0.24-0.93) but did not differ significantly with respect to any of the secondary outcomes. Asymptomatic hyperkalemia (>6 mEq/L) without characteristic electrocardiographic changes occurred in 3 patients (4%) in the protocol-based treatment group.
Not double-masked.
Compared with reactive potassium supplementation when the serum potassium level falls below 3.5 mEq/L, protocol-based oral potassium treatment to maintain a serum potassium concentration in the range of 4-5 mEq/L may reduce the risk of peritonitis in patients receiving PD who have hypokalemia.
Registered at the Thai Clinical Trials Registry with study number TCTR20190725004.
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Uremic toxins and gut dysbiosis in advanced chronic kidney disease (CKD) can induce gut leakage, causing the translocation of gut microbial molecules into the systemic circulation. Lipopolysaccharide ...(LPS) and (1→3)-β-D-glucan (BG) are the major gut microbial molecules of Gram-negative bacteria and fungi, respectively, and can induce inflammation in several organs. Here, the fibrosis in the kidney, liver, and heart was investigated in oral
-administered 5/6 nephrectomized (
-5/6 Nx) mice. At 20 weeks post 5/6 Nx,
-5/6 Nx mice demonstrated increased 24 h proteinuria, liver enzymes, and serum cytokines (TNF-α, IL-6, and IL-10), but not weight loss, systolic blood pressure, hematocrit, serum creatinine, or gut-derived uremic toxins (TMAO and indoxyl sulfate), compared to in 5/6 Nx alone. The gut leakage in
-5/6 Nx was more severe, as indicated by FITC-dextran assay, endotoxemia, and serum BG. The areas of fibrosis from histopathology, along with the upregulated gene expression of Toll-like receptor 4 (
) and
, the receptors for LPS and BG, respectively, were higher in the kidney, liver, and heart. In vitro, LPS combined with BG increased the supernatant IL-6 and TNF-α, upregulated the genes of pro-inflammation and pro-fibrotic processes,
, and
in renal tubular (HK-2) cells and hepatocytes (HepG2), when compared with LPS or BG alone. This supported the pro-inflammation-induced fibrosis and the possible LPS-BG additive effects on kidney and liver fibrosis. In conclusion, uremia-induced leaky gut causes the translocation of gut LPS and BG into circulation, which activates the pro-inflammatory and pro-fibrotic pathways, causing internal organ fibrosis. Our results support the crosstalk among several organs in CKD through a leaky gut.
Although the prevalence of obesity and metabolic syndrome (MetS) among dialysis patients has been exceeding than general population, little is known regarding obesity and MetS in non-dialysis chronic ...kidney disease (CKD). We aimed to find the magnitude of obesity and MetS and their associations with impaired renal function among type 2 diabetes mellitus (T2DM) patients.
A national survey of T2DM patients was collected in the Thai National Health Security Office database during 2014-5. The sampling frame was designated as distinct geographic regions throughout the country. A stratified two-stage cluster sampling was used to select the study population. Anthropometry and 12-hour fasting blood samples were obtained by trained personnel. BMI of ≥25 kg/m2 was classified as obesity. MetS was defined as having elevated waist circumference (>90 and >80 cm in men and women, respectively) plus any two of the followings: triglyceride ≥150 mg/dL, HDL-C <40 in men or <50 mg/dL in women, blood pressure ≥130/85 mmHg, and fasting blood sugar ≥100 mg/dL. CKD was defined as an impaired renal function (eGFR <60 mL/min/1.73m2 according to the CKD-EPI equation). Logistic regression analysis was performed to examine the relationship between obesity and MetS with the presence of CKD.
A total of 32,616 diabetic patients were finally recruited from 997 hospitals. The mean age was 61.5±10.9 years with 67.5% women. Of the participants, 35.4% were CKD patients. The prevalence of obesity was 46.5% in CKD and 54.1% in non-CKD patients with T2DM (p<0.001). In contrast, the prevalence of MetS in CKD patients was higher than their non-CKD counterparts (71.3 vs 68.8%, p<0.001). Moreover, there was an association between the prevalence of MetS with CKD stage from 3a to 5 (70.1, 72.3, 73.4, and 72.7%, respectively, p trend = 0.02). MetS, but not obesity, had a significant association with CKD in T2DM patients after adjusting for age, sex, and comorbidities OR 1.14; 95% CI 1.06-1.22, p<0.001. When stratified by each component of MetS, only high serum triglyceride and low HDL-C levels were increased in patients with CKD stage 4 and 5 compared with CKD stage 3 (p<0.001) and had a significant relationship with impaired renal function.
There were relatively high prevalences of both obesity and MetS in T2DM patients. A higher prevalence of MetS, but lower prevalence of obesity, was observed among diabetic CKD group compared with their non-CKD counterparts. MetS, as a surrogate of insulin resistance, appeared to be more important than obesity in the development of impaired renal function in diabetic population.
A chronic kidney disease (CKD) causes uremic toxin accumulation and gut dysbiosis, which further induces gut leakage and worsening CKD. Lipopolysaccharide (LPS) of Gram-negative bacteria and ...(1➔3)-β-D-glucan (BG) of fungi are the two most abundant gut microbial molecules. Due to limited data on the impact of intestinal fungi in CKD mouse models, the influences of gut fungi and
L34 (L34) on CKD were investigated using oral
-administered 5/6 nephrectomy (5/6Nx) mice. At 16 weeks post-5/6Nx,
-5/6Nx mice demonstrated an increase in proteinuria, serum BG, serum cytokines (tumor necrotic factor-α; TNF-α and interleukin-6), alanine transaminase (ALT), and level of fecal dysbiosis (Proteobacteria on fecal microbiome) when compared to non-
-5/6Nx. However, serum creatinine, renal fibrosis, or gut barrier defect (FITC-dextran assay and endotoxemia) remained comparable between
- versus non-
-5/6Nx. The probiotics L34 attenuated several parameters in
-5/6Nx mice, including fecal dysbiosis (
and
), gut leakage (fluorescein isothiocyanate (FITC)-dextran), gut-derived uremic toxin (trimethylamine-
-oxide; TMAO) and indoxyl sulfate; IS), cytokines, and ALT. In vitro, IS combined with LPS with or without BG enhanced the injury on Caco-2 enterocytes (transepithelial electrical resistance and FITC-dextran permeability) and bone marrow-derived macrophages (supernatant cytokines (TNF-α and interleukin-1 β; IL-1β) and inflammatory genes (
,
,
, and
)), compared with non-IS activation. These injuries were attenuated by the probiotics condition media. In conclusion,
administration worsens kidney damage in 5/6Nx mice through systemic inflammation, partly from gut dysbiosis-induced uremic toxins, which were attenuated by the probiotics. The additive effects on cell injury from uremic toxin (IS) and microbial molecules (LPS and BG) on enterocytes and macrophages might be an important underlying mechanism.
Viewed in renal physiology as a refined filtration device, the glomerulus filters large volumes of blood plasma while keeping proteins within blood circulation. Effects of macromolecule size and ...macromolecule hydrodynamic interaction with the nanostructure of the cellular layers of the glomerular capillary wall on the glomerular size selectivity are investigated through a mathematical simulation based on an ultrastructural model. The epithelial slit, a planar arrangement of fibers connecting the epithelial podocytes, is represented as a row of parallel cylinders with nonuniform spacing between adjacent fibers. The mean and standard deviation of gap half-width between its fibers are based on values recently reported from electron microscopy. The glomerular basement membrane (GBM) is represented as a fibrous medium containing fibers of two different sizes: the size of type IV collagens and that of glycosaminoglycans (GAGs). The endothelial cell layer is modeled as a layer full of fenestrae that are much larger than solute size and filled with GAGs. The calculated total sieving coefficient agrees well with the sieving coefficients of ficolls obtained from in vivo urinalysis in humans, whereas the computed glomerular hydraulic permeability also falls within the range estimated from human glomerular filtration rate (GFR). Our result indicates that the endothelial cell layer and GBM significantly contribute to solute and fluid restriction of the glomerular barrier, whereas, based on the structure of the epithelial slit obtained from electron microscopy, the contribution of the epithelial slit could be smaller than previously believed.
Central diabetes insipidus (DI) is characterized by a deficiency in arginine vasopressin (AVP), an antidiuretic hormone leading to excessive free water loss in the urine and hypernatremia. Central DI ...can be the first presentation of several occult diseases. However, patients with central DI who have functioning thirst mechanisms and access to water may initially exhibit normal sodium levels. We report a 57-year-old woman who was admitted to the hospital due to cholangitis. Her initial serum sodium was normal and she rapidly developed severe hypernatremia after fluid restriction. The results of the laboratory workup indicated DI, which dramatically responded to desmopressin. MRI showed an ill-defined faint hyper signal intensity in T1, T2/FLAIR lesions involving the bilateral hypothalamus. The histopathological findings confirmed the diagnosis of Langerhans cell histiocytosis (LCH) with multiorgan involvement. Serum sodium returned to normal after receiving desmopressin and water replacement therapy.
Recombinant human erythropoietin (r-HuEpo) has been used for the treatment of renal anemia. With the loss of its patent protection, there has been an upsurge of more affordable biosimilar agents, ...increasing patient access to treatment for these conditions. The complexity of the manufacturing process for these recombinant proteins, however, can result in altered properties that may significantly affect patient safety. As it is not known whether various r-HuEpo products can be safely interchanged, we studied 30 patients with chronic kidney disease treated by subcutaneous injection with biosimilar r-HuEpo and who developed a sudden loss of efficacy. Sera from 23 of these patients were positive for r-HuEpo-neutralizing antibodies, and their bone marrow biopsies indicated pure red-cell aplasia, indicating the loss of erythroblasts. Sera and bone marrow biopsies from the remaining seven patients were negative for anti-r-HuEpo antibodies and red-cell aplasia, respectively. The cause for r-HuEpo hyporesponsiveness was occult gastrointestinal bleeding. Thus, subcutaneous injection of biosimilar r-HuEpo can cause adverse immunological effects. A large, long-term, pharmacovigilance study is necessary to monitor and ensure patient safety for these agents.
Background: Tenofovir disoproxil fumarate (TDF) can induce proximal renal tubulopathy (PRT) and necessitate changes in treatment regimen. This prospective study aimed to compare tubular function ...recovery following early switching versus late switching of TDF in human immunodeficiency virus (HIV)-infected patients with TDF-induced PRT.
Methods: For this prospective study, conducted during 2017-2019, we enrolled HIV-1-infected, virologically suppressed adults undergoing TDF-containing combination antiretroviral therapy. Patients were separated into a late-switching group (LSG) and an early-switching group (ESG). The LSG included patients having an estimated glomerular filtration rate (eGFR) decrease ≥25% from the pretreatment level or Fanconi syndrome. The ESG included patients having ≥2 of the following indicators of PRT: fractional excretion of phosphate (FEUP) ≥10%, low tubular maximum reabsorption of phosphate (TmP)/GFR, or uricosuria; fractional uric acid excretion ≥10%; urine protein-creatinine index (UPCI) ≥500 mg/g creatinine, normoglycemic glycosuria, or decrease in eGFR of 15%-24%. Recovery of proximal tubular function at 6 and 12 months after TDF discontinuation was assessed. Complete recovery was defined as normalization of all abnormal tubular markers.
Results: Thirty-three HIV-infected patients were enrolled (70% male). Except for tubular function markers, baseline characteristics were not significantly different between the two groups. The proportion of patients having complete recovery was significantly higher in the ESG (p = 0.007, log-rank test). FEUP improved significantly in the ESG after TDF discontinuation; improvements of eGFR and UPCI were greater in the LSG. An eGFR change of 10% from baseline was the only independent predictor of failure to achieve complete recovery after switching. After median follow-up of 2.25 years post-trial, sustained recovery of eGFR within 5% of pre-TDF eGFR was achieved only in the ESG.
Conclusions: Early-switching of TDF in HIV patients with PRT may allow complete recovery of proximal renal tubular function.
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