Impact of Serum Bicarbonate Levels on Muscle Mass and Kidney Function in Pre-Dialysis Chronic Kidney Disease Patients.

BACKGROUND: Treatment of metabolic acidosis to target the higher serum bicarbonate level than guideline recommendation may downregulate muscle protein degradation and improve renal function among chronic kidney disease (CKD) patients. We conducted a study to test the effects of increased serum bicarbonate level on muscle parameters, nutrition, and renal function in pre-dialysis CKD patients. METHODS: This was a randomized, controlled study. CKD stage 3-4 patients with serum HCO3- <22 mEq/L were randomized to either receive oral sodium bicarbonate with high target bicarbonate level of 25 ± 1 or standard level of 22 ± 1 mEq/L as control group using protocol-based titration of dosage adjustment. The changes of muscle mass measured by bioelectrical impedance analysis (BIA), muscle strength by hand grip dynamometer, estimated glomerular filtration rate (eGFR) using CKD-Epidemiology Collaboration equation, nutritional markers, and muscle-related biomarkers were determined. Data at baseline and after 4 months of sodium bicarbonate supplementation were compared between groups using Student t test or chi-square test as appropriate. RESULTS: Forty-two patients completed the study (n = 21 per group). The mean age and eGFR were 61.2 ± 9.8 years and 32.4 ± 14.1 mL/min respectively. Serum bicarbonate levels at baseline were 21.0 ± 2.1 mEq/L. Baseline data including sex, diabetes, serum bicarbonate level, creatinine, and blood pressure were similar. After 4 months of treatment, the average serum bicarbonate levels in both groups were 24.0 ± 1.4 and 20.7 ± 2.3 mEq/L (p < 0.001). Both BIA-derived total-body muscle mass and appendicular lean balance were increased at 4 months in the higher bicarbonate group (26.0 ± 5.3 to 26.7 ± 5.5 kg, p = 0.04 and 19.8 ± 4.1 to 20.7 ± 4.4 kg, p = 0.06, respectively) despite comparable body weight and protein intake. Patients in the high bicarbonate group had a significant reduction of plasma myostatin levels, a surrogate of muscle degradation, at the study exit after adjusting for baseline values (-3,137.8; 95% CI -6,235.3 to -40.4 pg/mL, p= 0.04), but unaltered insulin-like growth factor-1 level, as the mediator of muscle cell growth, (141 [106-156] to 110 [87-144] ng/mL, p = 0.13) compared to the control group. Muscle strength, eGFR as well as serum prealbumin were not significantly different between 2 groups (p > 0.05). Neither worsening hypertension nor congestive heart failure was found throughout the study. CONCLUSION: Bicarbonate supplementation to achieve the serum level ∼24 mEq/L demonstrates better muscle mass preservation in patients with pre-dialysis CKD. The impact of alkaline therapy on renal function may require a longer period of study.

Management and outcome of severe acute pancreatitis.

BACKGROUND: The treatment of severe acute pancreatitis (SAP) varies among several institutes. It has been evolving from routine surgical management to conservative management in the early stages. The surgical management has a role in the later stages of the disease. OBJECTIVE: The purpose of the present study was to review the management and outcome of the patients with SAP at King Chulalongkorn Memorial Hospital, Bangkok, Thailand. MATERIAL AND METHOD: Two hundred and ten patients with a diagnosis of acute pancreatitis at King Chulalongkorn Memorial Hospital, Bangkok, Thailand from December 2001 to April 2005 were studied by retrospective chart review. RESULTS: Forty patients were diagnosed with SAP, 27 men and 13 women. SAP was most commonly caused by alcohol abuse (47.5%) and biliary tract disease (37.5%). Eighteen patients (45%) had pancreatic necrosis. Among them, seven patients (38.9%) had infected necrosis, and the rest had sterile necrosis. All patients with infected pancreatic necrosis underwent open pancreatic necrosectomy, and three of 7 died. Four of 11 patients with sterile necrosis died. The overall mortality was 25%. CONCLUSION: Patients with SAP have high morbidity and mortality rates. The patients with infected pancreatic necrosis may require surgical management, whereas those with sterile necrosis or SAP without local complications can be managed with conservative treatment and/or intervention. Post-operative complications might occur, thus require long term follow-up.

Reliability of blood pressure parameters for dry weight estimation in hemodialysis patients.

Chronic volume overload resulting from interdialytic weight gain and inadequate fluid removal plays a significant role in poorly controlled high blood pressure. Although bioimpedance has been introduced as an accurate method for assessing hydration status, the instrument is not available in general hemodialysis (HEMO) centers. This study was conducted to explore the correlation between hydration status measured by bioimpedance and blood pressure parameters in chronic HEMO patients. Multifrequency bioimpedance analysis was used to determine pre- and post-dialysis hydration status in 32 stable HEMO patients. Extracellular water/total body water (ECW/TBW) determined by sum of segments from bioimpedance analysis was used as an index of hydration status. The mean age was 57.9 ± 16.4 years. The mean dry weight and body mass index were 57.7 ± 14.5 kg and 22.3 ± 4.7 kg/m(2), respectively. Pre-dialysis ECW/TBW was significantly correlated with only pulse pressure (r = 0.5, P = 0.003) whereas post-dialysis ECW/TBW had significant correlations with pulse pressure, systolic blood pressure, and diastolic blood pressure (r = 0.6, P = 0.001, r = 0.4, P = 0.04, r = -0.4, and P = 0.02, respectively). After dialysis, the mean values of ECW/TBW, systolic blood pressure, mean arterial pressure, and pulse pressure were significantly decreased. ECW/TBW was used to classify the patients into normohydration (≤ 0.4) and overhydration (>0.4) groups. Systolic blood pressure, mean arterial pressure, and pulse pressure significantly reduced after dialysis in the normohydration group but did not significantly change in the overhydration group. Pre-dialysis pulse pressure, post-dialysis pulse pressure, and post-dialysis systolic blood pressure in the overhydration group were significantly higher than normohydration group. Due to the simplicity and cost, blood pressure parameters, especially pulse pressure, might be a simple reference for clinicians to determine hydration status in HEMO patients.

Comparisons between validated estimated glomerular filtration rate equations and isotopic glomerular filtration rate in HIV patients.

OBJECTIVE: Understanding how best to measure renal function in HIV-infected patients is critical because estimated glomerular filtration rate (eGFR) in HIV-infected patients can be affected by ethnicity and body composition. We validated the available eGFR equations and compared them to the plasma Tc-diethylenetriaminepentaacetic acid (Tc-DTPA) clearance in HIV-infected patients. DESIGN: Test of diagnostic accuracy. METHODS: One hundred and ninety-six HIV-infected patients underwent measuring of Tc-DTPA plasma clearance, five creatinine-based eGFR equations, cystatin-C GFR, and 24-h urine creatinine clearance (CrCl). RESULTS: Mean (SD) Tc-DTPA GFR was 117.7 ± 29.2 ml/min per 1.73 m. The re-expressed Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), re-expressed MDRD formula with Thai racial correction factor, Thai eGFR equation, Cockcroft-Gault equation, cystatin-C GFR, and 24-h urine CrCl underestimated the reference GFR. The bias estimated by the mean of differences (SD) for the re-expressed MDRD equation, CKD-EPI, re-expressed MDRD formula with Thai racial correction factor, Thai eGFR, Cockcroft-Gault equation, cystatin-C, and 24-h urine CrCl can be expressed as 18.9 ± 27.3, 11.1 ± 25.5, 6.2 ± 28.8, 15.4 ± 27.0, 30.4 ± 28.0, 3.2 + 36.1, and 5.0 ± 12.1 ml/min per 1.73 m, respectively. CONCLUSION: The available eGFR equations underestimated GFR in HIV-infected adults. However, the eGFR by cystatin-C GFR was the most precise and accurate. Among creatinine-based eGFR equations, re-expressed MDRD formula with Thai racial correction factor was the most precise and accurate. The racial factor for each ethnicity is important and the existing eGFR equation should be validated before using it in the HIV population.