Renin-angiotensin-aldosterone system in mild diabetic nephropathy

The mechanism of lowered renin-aldosterone system was investigated in 17 patients with diabetic nephropathy (serum Cr less than 3 mg/100 ml) with concomitant control of the blood sugar level. The response of plasma renin activity (PRA) to upright stimulation was lower in the low renin group (group I) than in the normal to high renin group (group II) and in the control group. The PRA response to theophylline was delayed in group I. The percentage of the luminal area of the arteriole in the biopsy specimens was larger in group I and the control group than in group II. Plasma aldosterone concentration (PAC) was not increased by angiotensin II in group I. Low PRA in diabetic nephropathy with slightly to moderately impaired renal function may not be due to hyaline destruction of the arteriolar walls, but to other factors such as sympathetic nervous dysfunction. The adrenal responses of PAC to angiotensin II may also be impaired.     

Interim evidence of the renoprotective effect of the angiotensin II receptor antagonist losartan versus the calcium channel blocker amlodipine in patients with chronic kidney disease and hypertension: a report of the Japanese Losartan Therapy Intended for Global Renal Protection in Hypertensive Patients (JLIGHT) Study

Background. Insufficiency of renal function and high blood pressure influence each other and eventually result in life-threatening endstage renal disease. It has been proposed that proteinuria per se is a determinant of the progression of chronic kidney disease (CKD). The therapeutic strategy for patients with proteinuric CKD and hypertension should therefore be targeted with a view not merely toward blood pressure reduction but also toward renoprotection. Methods. We examined the effect of the angiotensin (AT)₁ receptor antagonist losartan and the calcium channel blocker amlodipine, throughout a period of 12 months, on reduction of blood pressure and renoprotection. This was done by assessing amounts of urinary protein excretion, serum creatinine (SCr), and creatinine clearance (CCr) in patients with hypertension (systolic blood pressure [SBP] 140mmHg or diastolic blood pressure [DBP] 90mmHg) and CKD (male, body weight [BW] 60kg: 1.5 SCr < 3.0mg/dl; female or male BW < 60kg: 1.3 SCr < 3.0mg/dl), manifesting proteinuria of 0.5g or more/day. Losartan was administered once daily at doses of 25 to 100mg/day, and amlodipine was given once daily at 2.5 to 5mg/day. No antihypertensive combination therapy was allowed during the first 3-month period. Results. A 3-month interim analysis revealed that, despite there being no difference in blood pressure between the two groups, there was a significant reduction in 24-h urinary protein excretion in the losartan group (n = 43), but there was no change in the amlodipine group (n = 43). Analysis of stratified subgroups with proteinuria of 2g or more/day and less than 2g/day showed that losartan lowered proteinuria by approximately 24% in both subgroups, while amlodipine lowered proteinuria by 10%, but only in the subgroup of less than 2g/day (NS). SCr and CCr did not change throughout the period of 3 months in either group. No severe or fatal adverse event was experienced in either group during the study period. Conclusions. Losartan appeared to be efficacious for renoprotection in patients with proteinuric CKD and hypertension, with the mechanism being independent of its antihypertensive action.     

A case of paroxysmal nocturnal hemoglobinuria combined with focal segmental glomerular sclerosis

A 81-year-old woman was admitted to our hospital because of edema and massive proteinuria on September 26, 1995. On admission, the palpebral conjuctiva were slightly anemic, and edema of the eyelids and legs was observed. Laboratory findings were as follows, urine protein(3+), occult blood(3+), WBC 2,600/microliter, Hgb 10.0 g/dl, reticulocytes 20@1000, TP 5.0 g/dl, Alb 2.7 g/dl, T-Cho 376 mg/dl, TG 194 mg/dl, LDH 763 U/l, haptoglobin < 93 mg/dl, Ham's test(+), sugar water test(+), and indirect coombs (+). The erythrocytes of this patient showed a negative population consisting of double negative erythrocytes evaluated by flow cytometric two-color analysis using monoclonal antibodies specific to CD55 and CD59. From these findings, the diagnosis of paroxysmal nocturnal hemoglobinuria(PNH) was made. The patient showed nephrotic syndrome and a renal biopsy was performed. The histological findings of renal biopsy showed focal and segmental sclerosis and adhesion of glomerular tufts. Interstitial fibrosis with atrophic tubules and lymphocyte infiltration were also observed. There was no specific staining of immunoglobulins and complement by immunofluorescence. The diagnosis of focal segmental glomerular sclerosis(FSGS) was made. There have been only three case reports of glomerular disease in patients with PNH, such as purpura nephritis, IgA nephropathy and membranous nephropathy. The complication of FSGS and PNH is every rare and there has been no report of FSGS in a case with PNH. The onset of PNH resulted from the loss of CD55 and CD59, which was critical in the onset of FSGS in the present case.     

A case report of chronic chyluria probably due to Bancroftian filariasis, which showed hypoproteinemia

Proteinuria is commonly observed in patients with chyluria due to Bancroftian filariasis. However, whether or not hypoalbuminemia is caused by chyluria alone is still a matter of debate. This is because various forms of glomerulonephritis are complicated in such patients. Herein, we report a case we have recently encountered. A 72-year-old male was admitted to our division for further evaluation of nephrotic syndrome. He was from the Southernmost part of Japan, where Bancroftian filariasis has been epidemic, and had developed persistent chyluria over a period of nearly 50 years. There was no other past history of illness except for diabetes mellitus(DM) pointed out 3 months prior to admission. The physical and laboratory examinations on admission fulfilled the diagnostic criteria for nephrotic syndrome. Lymphoscintigraphy showed an intense tracer accumulation in both kidneys. A renal biopsy was performed. At the light microscopic level, the glomeruli looked normal. Edema of the tubulointerstitium was noted. At the electron microscopic level, effacement of podocyte foot processes was not observed. Immunofluorescent study did not show glomerular deposition of immunoglobulins and complements. He also had persistent microscopic hematuria. Automated urinary sediment analysis by real-time confocal scanning laser microscopy revealed red blood cells of the non-glomerular type. Taken together, these findings strongly indicated that hypoalbuminemia of this patient was caused by chyluria alone. In conclusion, a report of the present case provides strong evidence that hypoalbuminemia of a patient with Bancroftian filariasis could be caused by chyluria alone.