Relation of kidney size to kidney function in early insulin-dependent diabetes

Abstract

Summary. Renal function and renal size have been studied in ten early insulin-dependent diabetic patients and in ten matched control subjects. Glomerular filtration rate, renal plasma flow and radiological kidney size were determined in each subject. Glomerular filtration rate and renal plasma flow were increased in diabetics (mean ___ SD: 169.6+ 16.1 and 690.1___52.6 ml/min/1.73 m 2, respectively) compared with controls (120.6+9.7 and 605.9+67.2 ml/ rain/1.73 m2; p < 0.001 and p < 0.01). Calculated kidney weight corrected to 1.73 m 2 of body surface area was elevated in diabetics (385.2+29.0 g) with respect to controls (277.5_17.5g; p <0.001). No significant differences were found between diabetics and control subjects when glomerular filtration rate was expressed per gram calculated kidney weight, while renal plasma flow was significantly lower in diabetics than control Subjects when so expressed (p <0.01). A positive correlation was found between glomerular filtration rate, renal plasma flow and kidney size in both controls and diabetics (p < 0.01 in all cases). These findings support the conclusion that in the early state of diabetes glomerular hyperfunction is related to enlargement of the kidneys and augmented renal plasma flow.

Relationship of renal size to nephropathy in Type 1 (insulin-dependent) diabetes

“…Within a few years, exercise-induced [9] and resting [10] microalbuminuria are also noted. In newly diagnosed diabetic patients [4] and in patients with duration up to 12 years [3,6,7], a direct relationship has been found between GFR and kidney size measured either by X-ray or by ultrasound. It is not know whether these early abnormalities have any value in predicting whether an individual patient has a relatively increased or decreased risk of the development of overt clinical nephropathy, characterised by Albustix-positive proteinuria, hypertension, and declining GFR, culminating, ultimately, in end-stage renal disease.…”

“…Nephropathy is a major complication of diabetes mellitus and results in renal failure in at least one-third of Type 1 diabetic patients within 15-30 years of the onset of the disease [1,2]. Usually at diagnosis there are subtle renal functional and structural changes which include elevated glomerular filtration rate (GFR) [3][4][5][6][7][8], renal plasma flow [3][4][5][6][7][8], and increased kidney size [3][4][5][6][7][8]. Within a few years, exercise-induced [9] and resting [10] microalbuminuria are also noted.…”

Early markers of the renal complications of insulin dependent diabetes mellitus.

“…A high glomerular filtration rate has been reported in 20-30% of diabetic children under conditions of standard insulin treatment,1416 and although poorly studied in childhood, increased renal size has been described in adults with IDDM, both at diagnosis and during the early years of the disease. [17][18][19] Hypertension is an accepted feature of diabetic nephropathy after the appearance of microalbuminuria and its treatment has been shown to slow the decline of renal function.2" 21 In children with IDDM, blood pressure data are conflicting, but where increases have been shown, they have been small. 22 24 A problem in most of these studies is the choice of controls.…”

An Inhibition of Urinary Albumin Excretion by Protease Inhibitor in Streptozotocin-Diabetic Rats

“…It is well known that kidney size is increased in diabetes mellitusof recent onset and in experimental diabetic animals [8][9][10], In both humans and animals the high glomerular filtra tion rate of diabetics is invariably accompanied by in creased volume of the kidney [8,[10][11][12], Renal hypertro phy and hyperfunction in early diabetes have been sug gested as initiating or accelerating late diabetic nephropa thy [13,14], although the exact mechanism is unknown. These results suggest that an inhibitory effect on UAE of camostat mesylate correlates partly with the inhibitory effect on initial diabetic renal hypertrophy.…”