The pathologic physiology of chronic Bright's disease. An exposition of the "intact nephron hypothesis".

Clinical and experimental data relating to the functional capacity of the surviving nephrons of the chronically diseased kidney for the most part support the thesis that these nephrons retain their essential functional integrity regardless of the nature of the underlying form of chronic Bright's disease. There are instances in which specific alterations of function correlate with pathologic involvement of a particular site of the nephron but these appear to represent the exceptions, and in general the more advanced the disease becomes, the less evident are the differentiating features. Studies on dogs with unilateral renal disease indicate that the functional capacity of the nephrons of the diseased kidney parallels that of the nephrons of the contralateral normal kidney. These data tend to exclude widespread intrinsic damage to the functioning nephrons by the underlying pathologic processes. From these observations, as well as from certain supporting clinical and experimental observations, it is suggested that the majority of surviving nephrons in the patient with bilateral renal disease similarly are functionally intact. Concepts of the pathologic physiology of the kidney, based on the "intact nephron hypothesis", are presented. Within the framework of this hypothesis it is concluded that (1) the diseased kidney consists of a diminished number of nephrons, most of which retain essentially normal functional abilities; (2) certain of the apparent abnormalities in function in bilateral renal disease may relate to adaptive changes imposed by the decreased nephron population and the attendant derangements in body fluids rather than to structural distortion of nephrons; (3) the over-all flexibility of the diseased kidney decreases as the number of constituent nephrons decreases; but (4) there is an orderly and predictable pattern of excretion for all substances.

A controlled trial of cyclosporine in patients with progressive membranous nephropathy. Canadian Glomerulonephritis Study Group.

A controlled trial of cyclosporine in patients diagnosed with progressive membranous nephropathy (MGN) was carried out to determine whether cyclosporine (D) would be more effective than placebo (P) in reducing the rate of deterioration in renal function. Patients (N = 64) with MGN were placed on a restricted protein diet (< or = 0.9 g/kg) and followed closely for 12 months (Part 1). Patients at high risk of progression based on an absolute loss in creatinine clearance (CCr) of > or = 8 ml/min and persistent nephrotic range proteinuria (Pr) were selected and randomly assigned to either (D) (N = 9) or (P) (N = 8) for 12 months (Part 2). No differences in the two groups were noted at entry. After 12 months, the improvement in CCr slope in ml/min/month was significantly greater in the D patients (D + 2.1 vs. P + 0.5, mean difference 1.6; 95% CI 0.3 to 3.0, P < 0.02). This improvement was maintained in six of eight D (75%) over a mean follow-up period of 21 months. Daily Pr also improved with D (by month 3, D - 4.5 g/day vs. P + 0.7 g/day, P = 0.02) and was sustained in six of eight (75%) D patients. When Pr was expressed as a function of their concurrent CCr, the D versus P patients' time to halving was faster (P = 0.02) and absolute number higher (4/9 D vs 0/8 P). In the D group a trend towards worse hypertension and an increase in the number of transient rises in serum creatinine were noted.(ABSTRACT TRUNCATED AT 250 WORDS)

Mitral regurgitation due to lupus endocarditis treated with valve replacement.

A murmur of mitral regurgitation developed in a 20-year-old woman with a 2-year history of systemic lupus erythematosus. Echocardiography revealed thickening of both valve leaflets and abnormal diastolic motion of the posterior one, confirming the diagnosis of mitral endocarditis. The mitral regurgitation progressed to cause congestive heart failure, which was refractory to drug therapy but was effectively treated with mitral valve replacement.

Use of computerized tomography to evaluate bleeding after renal biopsy.

Perirenal bleeding following biopsy was assessed in 25 consecutive cases using computerized axial tomography (CT) scanning. Perirenal hematomas were found in 15 patients (60%). In 8 patients the hematomas were moderate or large in size. There was no correlation between the clinical findings, fall in hemoglobin, presence of macroscopic hematuria and the finding of perirenal hematoma by CT scanning.

The protean manifestations of renal vein thrombosis in the adult.

We reviewed 8 cases of renal vein thrombosis, 4 of which were detected at autopsy, 1 by laparotomy and the remaining 3 by venography. In 4 cases malignancy also was found and in 2 membranous glomerulonephritis was noted. In 1 patient the thrombosis occurred in a solitary kidney, while it was bilateral in 3. The 4 patients in whom the diagnosis was made during life were treated with anticoagulants alone and 3 are alive with stable renal function 3, 4 and 7 1/2 years after diagnosis.

Emphysematous pyelonephritis.

A case of emphysematous pyelonephritis with perirenal gas is presented. This patient underwent vigorous medical treatment followed by nephrectomy and survived. This condition has a high mortality and should be distinguished from less severe infections where gas is confined to the collecting system. This case and others previously reported suggest that treatment should initially be medical, followed by early surgical intervention consisting of either drainage or nephrectomy depending upon the degree of renal involvement.

An artificial kidney system suitable for multiple simultaneous dialysis.

The standard twin-coil Kolff artificial kidney has been redesigned to a single-pass system employing cold dialysis, bath-heated and recirculated within the coil. With considerably reduced bath requirements, a comparable dialysis is achieved in spite of a lower bath-to-blood urea gradient. Coil pressure is monitored by a simplified high-and-low pressure control system linked to a specially designed roller blood pump. The re-use of priming blood and disposable coils have proved economical and feasible. A considerable reduction in bacterial growth has been achieved. The Kolff system retains its capacity in the management of acute renal failure and has proved efficient in twice-weekly six-hour chronic hemodialyses.