Decrease Rate of the Renal Diameter in Chronic Hemodialysis Patients

We here present the results of ultrasonographic (US) evaluations on the alteration of renal diameter of chronic HD patients. Of 109 outpatient HD patients who had neither severe acquired cystic disease of the kidney nor hereditary polycystic kidney disease, we performed US two or three times to measure their maximum renal diameter (mean of both kidneys), and the yearly alteration rate was calculated. The average interval of the two measurements was 35.9 months, and the average HD duration from the HD induction to the first measurement was 29.5 months. The average decrease rate of renal diameter was (SE) mm/year. No statistical difference was seen on the decrease rate in relation to gender, age and original disease (among three groups, glomerulonephritis and IgA nephropathy, diabetes, and others including hypertension). However, the decrease rate was large when the first measurement was close to the induction of hemodialysis, suggesting that the alteration rate reduced according to the hemodialysis vintage ( ？mm/year, first measurement not more than 10 months after induction of HD and ？mm/year, first measurement more than 80 months after induction of HD). Renal diameter decreased approximately 4.3？mm each year, and the decrease rate slowed as the length of time on dialysis increased. 1. Introduction It is well known that the kidney size of the patient undergoing chronic hemodialysis (HD) gradually decreases [1]. However, only a few reports are there on the study of the actual decrease rate [2–4]. On the other hand, scheduled ultrasonographic (US) examination of kidney after induction of HD is important to check the progression of acquired cystic disease of kidney (ACDK) and renal cancer which may arise in ACDK [5, 6]. We examined the renal longest diameter of chronic HD patient at the scheduled US kidney checkup [7], calculated the alteration rate of the size in the same patients, and studied the difference of the alteration rate among the factors such as gender, age, and original diseases. 2. Subjects and Methods Of 229 outpatient chronic hemodialysis patients, 109 patients, who had neither hereditary polycystic disease nor severe acquired cystic disease of kidney, were selected; we performed ultrasonography (US) twice or three times to measure their maximum renal diameter (mean of both kidneys), and the yearly alteration rate of the diameter was calculated. The US study was performed by a sole medical examiner. The largest caliber of the imaged kidney was measured using the measurement tool loaded in the US machine (Aroca SSD-280, Toshiba Nemio 30,