Objectives: To evaluate the bladder capacity in patients diagnosed with end stage renal disease ( ESRD )
Material and Method: A six-month prospective study was conducted at the outpatient X-ray unit, Department of Radiology, King Chulalongkorn Memorial Hospital from July 2002 to January 2003. Datas from adult patients sent to the unit for voiding cystourethrography (VCUG) were collected. Bladder capacity was obtained by calculating the amount of contrast material introduced into the urinary bladder in each VCUG. The urinary bladder was assumed to be at the maximum capacity when the patient had a strong desire to void during contrast instillation. Patients with voiding dysfunction or neurogenic bladder were excluded from the present study.
Results: There were 11 patients with ESRD (male=7, female=4, mean age=41 years) and 7 patients without ESRD (male=1, female=6, mean age=41 years). The maximum bladder capacity was 400 ml for the ESRD patients and 500 ml for the non-ESRD patients. The smallest bladder capacity was 100 ml for the ESRD patients and 250 ml for the non-ESRD patients. The mean bladder capacity was 254.5 ml (+SD) for the patients with ESRD and was 364.28 ml for the patients without ESRD. The P-value was 0.043.
In conclusion, the mean bladder capcity of the patients with ESRD was statistically smaller than that of patients without ESRD.

Keywords: Bladder capacity, End stage renal disease, ESRD