Abstract: TH-PO1119

Urinary Acid Excretion in Overweight Patients with CKD

Session Information

Category: Fluid, Electrolytes, and Acid-Base

  • 704 Fluid, Electrolyte, Acid-Base Disorders


  • Izumi, Yuichiro, Kumamoto University, Kumamoto, Japan
  • Eguchi, Koji, Kumamoto University Graduate School of Medicine, Kumamoto, Kumamoto, Japan
  • Nakayama, Yushi, Kumamoto University, Kumamoto, Japan
  • Inoue, Hideki, Kumamoto University School of Medicine, Kumamoto, Japan
  • Nonoguchi, Hiroshi, Kitasato University Medical Center, Kitamoto, SAITAMA, Japan
  • Kakizoe, Yutaka, Department of Nephrology, Kumamoto university graduate school of medical sciences, Kumamoto, Japan
  • Kuwabara, Takashige, Kumamoto University Graduate School of Medical Sciences, Kumamoto, Japan
  • Mukoyama, Masashi, Kumamoto University Graduate School of Medical Sciences, Kumamoto, Japan

Urinary ammonium excretion, which reflects acid excretion by the kidney, has been suggested as a predictor for the chronic kidney disease (CKD) outcome. Overweight is one of the risk factors for progression of CKD. We examined urinary acid excretion in overweight CKD patients.


25 Japanese out-patients with CKD who were treated with diet and medical therapy in our hospital were enrolled to evaluate acid excretion by the kidney. A 24-h urine collection was performed one day before visiting our hospital to determine excretion of creatinine, protein, urea, ammonium, pH, titratable acid (TA) and other electrolytes. Blood test was performed at visiting day. Their creatinine clearance (Ccr) corrected by body surface area was from 10 to 120 ml/min. For further analysis, patients, whose Ccr was > 30 ml/min, were divided into two groups: 11 normal (BMI 21 ± 2 kg/m2) and 10 overweight (28 ± 3 kg/m2) patients. Acid excretion between two groups was compared.


Both ammonium (Figure 1) and TA excretions decreased with the decrease of Ccr (r2 = 0.31, P = 0.0036 and r2 = 0.20, P = 0.028). Between two groups, ammonium excretion was significantly decreased in overweight patients compared to that in normal weight patients (Figure 2). TA excretion tended to be increased in overweight group, resulting in no difference of total acid excretion (calculated by ammonium + TA) between the two groups. While protein and sodium chloride intakes were greater in overweight, net endogenous acid production (NEAP) and Ccr were not different between the two groups.


There might be a modulation of acid excretion mechanism in overweight patients with CKD.


  • Government Support - Non-U.S.