Clinicopathological study of kidneys from patients on chronic dialysis

Kidneys removed from 58 pediatric patients at renal transplantation (except 3 cases), who had developed chronic renal failure and were maintained on dialysis, were investigated histopathologically, and the clinical profiles were taken into account. The patients ranged in age from 2 to 24 years, with an average of 11.2 years. The duration of dialysis ranged from 0.5 to 63 months, with an average of 12.6 months. The kidneys, which were conventionally prepared for histological observation, were subjectively divided into three groups depending on the degree of remaining nephrons. Patients with completely atrophic type (type 1), incompletely atrophic type (type 2), and mixed type of atrophy and hypertrophy (type 3) had a duration of dialysis of 20.0, 12.3, 6.3 months, respectively (Type 1 greater than Type 3, P less than 0.01). A correlation between histology and function was demonstrated, since urinary output was more than 200 ml/day in most of the type 3 patients, and less than 20 ml/day in all of the patients with type 1. The findings suggest that the functioning nephrons that remained at the beginning of dialysis generally become atrophic within one year after the initiation of dialysis. The ratio of kidney weight to body weight showed a significant negative correlation with both the duration of dialysis and that of illness. The histopathological changes seen in kidneys of patients on dialysis were reviewed. The findings suggested that certain changes, unusual epithelial proliferations an oxalate deposition, are associated with persisting renal function rather than the duration of dialysis.