Antiproteinuric effect of the calcium channel blocker cilnidipine added to renin-angiotensin inhibition in hypertensive patients with chronic renal disease.

Cilnidipine, a dual L-/N-type calcium channel blocker, dilates both efferent and afferent arterioles and is renoprotective. Our multi-center, open-labeled, and randomized trial compared the antiproteinuric effect of cilnidipine with that of amlodipine in hypertensive patients with kidney disease. A group of 339 patients, already receiving renin-angiotensin system inhibitor treatment, were randomly assigned to cilnidipine or amlodipine. The primary endpoint was a decrease in the urinary protein to creatinine ratio. After 1-year of treatment, systolic and diastolic blood pressures were significantly reduced in both groups which did not differ between them. The urinary protein to creatinine ratio significantly decreased in the cilnidipine compared to the amlodipine group. Cilnidipine exerted a greater antiproteinuric effect than amlodipine even in the subgroup whose blood pressure fell below the target level. This study suggests that cilnidipine is superior to amlodipine in preventing the progression of proteinuria in hypertensive patients when coupled with a renin-angiotensin system inhibitor.

Protein intake of more than 0.5 g/kg BW/day is not effective in suppressing the progression of chronic renal failure.

BACKGROUND: Although it is well-known that the restriction of protein intake in chronic renal failure (CRF) is effective in slowing the progressive loss of renal function, recent randomized controlled trials have not consistently shown a beneficial effect on CRF. There is controversy regarding the amount of protein intake that results in this effect. In this study, various amounts of protein intake were compared in CRF patients due to chronic glomerulonephritis (CGN) in order to explore effective restriction of dietary protein. METHODS: CGN patients (121 in total) with a serum creatinine level of 6 mg/dl were studied. They were subdivided into six groups depending on their protein intake: 0.3 g/kg BW/day (0.3 g), 0.4, 0.5, 0.6, 0.7, and > or =0.8 g (control group C). Deterioration of renal function was evaluated by the mean rate of decline in creatinine clearance, and the amount of protein intake was estimated on the basis of the urea nitrogen appearance rate in a 24-hour urine sample. RESULTS: There was no significant difference in the suppression of the progression of renal dysfunction in the 0.6- and 0.7-g groups. However, significant suppression was observed in the 0.5-, 0.4-, and 0.3-g groups in comparison with those that received more than 0.6 g (p < 0.05). The renal survival rate in the groups that received less than 0.5 g was higher than that in the groups that received more than 0.6 g (p < 0.05). Malnutrition was not observed in all patients studied. CONCLUSION: We found that a protein intake of more than 0.5 g/kg BW/day is not effective in suppressing further deterioration of renal function in CRF resulting from CGN.

Acquisition of the monocyte/macrophage phenotype in human mesangial cells.

The function of intrinsic glomerular cells in active glomerular inflammation may be similar to that of monocytes/macrophages. Mesangial cells have phagocytic properties and release numerous mediators. In this study we examined whether human mesangial cells (hMCs) express a monocyte/macrophage phenotype in active glomerular inflammation. We report that the proto-oncogene c-fms, the macrophage colony-stimulating factor (M-CSF) receptor, which is a characteristic gene of monocytes/macrophages, is expressed in hMCs. Normal unmanipulated hMCs express weak c-fms mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR), and its expression increases after stimulation with platelet-derived growth factor-BB (PDGF-BB) and epidermal growth factor (EGF). The expression of c-fms was also demonstrated by flow cytometry with a specific polyclonal antibody. By immunohistochemistry, c-fms was prominently detected in acute glomerulonephritis, IgA nephritis, and lupus nephritis. These results indicate that hMCs express c-fms in active glomerular inflammation and are consistent with mesangial cells acquiring some macrophage-like characteristics in diseased states.

[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.

Reversible nephrotic syndrome in a patient with amyloid A amyloidosis of the kidney following methicillin-resistant Staphylococcus aureus infection.

A common form of methicillin-resistant Staphylococcus aureus (MRSA) associated glomerulonephritis is either an endocapillary proliferative glomerulonephritis or a crescentic glomerulonephritis. This report describes the development of reversible nephrotic syndrome following MRSA infection in a patient with amyloid A amyloidosis. The patient had been diagnosed as having rheumatoid arthritis for 50 years. Suppurative arthritis due to MRSA became complicated 2 years prior to admission to our hospital. In the meantime, a nonnephrotic-range proteinuria developed. Two weeks before admission, nephrotic syndrome developed. The serum creatinine level remained unchanged throughout the course, but common features characteristic of MRSA-associated glomerulonephritis were observed in this patient, such as elevated serum IgG and IgA levels. A renal biopsy specimen showed glomerular amyloid A amyloidosis of a nodular type, infiltrated mononuclear cells in the mesangium, deposition of IgG, IgA, and C3, and swelling of glomerular endothelial cells. There were no crescentic glomeruli. Following surgical eradication of the MRSA focus in the right knee joint, nephrotic syndrome disappeared. Hence, it was highly possible that MRSA infection induced a reversible nephrotic syndrome by causing reversible injuries to glomerular endothelial cells. The description of this case serves to illustrate the range of MRSA infections that may cause various forms of glomerulonephritides.

[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.

[Two cases of idiopathic membranous nephropathy with focal and segmental glomerulosclerotic lesions in which renal function progressively deteriorated].

Previous reports have clarified that focal and segmental glomerulosclerosis(FSGS) appearing in membranous nephropathy(MN) is associated with a poorer prognosis than that of MN without FSGS. However, the etiology and pathogenesis of such FSGS lesions may show substantial individual differences. In some patients, hemodynamic alterations secondary to hypertension and vascular disorders seem to play a crucial role in the development of such FSGS lesions. In such instances, steady regulation of blood pressure might slow down further progression of FSGS lesions. Here we describe two cases of biopsy-proven MN with FSGS. Case I was a 44-year-old man who had shown massive proteinuria with hematuria at the age of 39 years. Renal biopsy specimens obtained at the age of 40 and 41 years showed MN without FSGS and MN with FSGS, respectively. His blood pressure control was fairly good throughout the course. Although he was on a steroid, an immunosuppressant, a low protein diet, and an ACE inhibitor, his renal function declined in 5 years. Case 2 was a 61-year-old woman who showed nephrotic syndrome at the age of 39 years. A renal biopsy specimen obtained at the age of 58 years showed MN with FSGS and remarkable atherosclerotic changes of the interlobular arteries. Her blood pressure control was rather poor throughout the course. Her renal function gradually declined over 22 years. Since parts of the FSGS lesions of the second case may have been caused by hypertension, it is tempting to speculate that day-to-day control of blood pressure could improve the long-term prognosis. We believe that, at least in some patients of MN with FSGS, careful management may lead to a more favorable course of decline in renal function.

Effect of plasma exchange on refractory hemophagocytic syndrome complicated with myelodysplastic syndrome.

A case of hemophagocytic syndrome (HPS) refractory to corticosteroid therapy was successfully treated by plasma exchange. The patient was a 56-year-old woman who had undergone regular hemodialysis for 10 years for complicated myelodysplastic syndrome (MDS) and then had had lung tuberculosis. After the onset of tuberculosis, she suffered from HPS and was treated by antituberculosis agents and high dose corticosteroid administration without any effect on the HPS. After adding a series of plasma exchanges, the HPS improved gradually, and her MDS began to respond to corticosteroid therapy. Plasma hypercytokinemia due to HPS was corrected by plasma exchange, and the correction of a high level of plasma inflammatory cytokine was considered to be one of the contributing factors for the improvement of HPS. These results suggest that therapeutic plasma exchange should be considered as a therapeutic tool for HPS refractory to conventional therapy.

Plasma exchange for acquired hemophilia: a case report.

A patient with acquired hemophilia complicated with chronic renal failure and lung tuberculosis was successfully treated by consecutive plasma exchange (PE). A 71-year-old man with serious bleeding tendency showed low coagulation factor levels and a high titer of factor VIII (FVIII) inhibitor, and he was diagnosed with acquired hemophilia. Because of the complication of active lung tuberculosis, instead of immunosuppressive therapy, he undertook a series of PE with fresh frozen plasma replacement for 3 months. After the start of PE, his bleeding symptoms and activated partial thromboplastin time (APTT) improved gradually according to the decrease in FVIII inhibitor levels. These results suggest that PE is an effective therapeutic tool for refractory acquired hemophilia.

Effect of simvastatin on proliferative nephritis and cell-cycle protein expression.

BACKGROUND: Mesangial cell proliferation is important in subsequent mesangial matrix expansion in glomerular injury. Therefore, the regulation of mesangial cell proliferation may be critical in the treatment of glomerulonephritis. Inhibition of 3-hydro-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibits the production of mevalonate and has been shown to suppress proliferation in many cell types, including mesangial cells in vitro. It is expected that HMG-CoA reductase inhibitor may suppress mesangial cell proliferation and subsequent progression of glomerulonephritis. Recently, the tight relationship between cell-cycle regulatory protein expression and mesangial cell proliferation in experimental glomerulonephritis was demonstrated. The aim of the present study is to examine the effect of simvastatin, one of the HMG-CoA reductase inhibitors, on the glomerular cell proliferation and on the expression of CDK2 or p27Kip1 in mesangial cells in experimental glomerulonephritis in vivo. METHODS: The effect of simvastatin on a rat mesangial proliferative glomerulonephritis induced by antithymocyte antibody (anti-Thy 1.1 GN) was studied. Administration of simvastatin or vehicle (for control GN) were started from two days before disease induction, and was continued to the day of nephrectomy. Nephrectomy was done at days 0, 2, 4, 7, 12 and 20 after disease induction. Immunohistochemistry for proliferating cells, macrophages, alpha-smooth muscle actin, type IV collagen and PDGF-B chain was performed, respectively, in addition to conventional periodic-acid Schiff staining. Double immunostaining for CDK2/OX-7 or p27Kip1/OX-7 was also done, respectively. RESULTS: There was no difference in the degree of the initial injuries between simvastatin-treated and control GN rats. The most pronounced feature of simvastatin-treated GN was the suppression of the early glomerular cell proliferation (about 70% of proliferation was suppressed at day 4). At day 4, alpha-smooth muscle actin expression was also decreased in simvastatin-treated GN rats. Inhibition of macrophage recruitment into glomeruli by simvastatin was also a prominent feature (about 30% decrease in the number of glomerular macrophages at day 2). Simvastatin significantly suppressed subsequent mesangial matrix expansion and type IV collagen accumulation in glomeruli. Although it might simply reflect the reduction in mesangial cells, glomerular PDGF-B chain expression was reduced. There was no significant difference in plasma lipids levels at day 2 and day 4. In vehicle-treated GN rats, the number of CDK2+/OX-7+ cells (CDK2-expressed mesangial cells) in glomeruli increased significantly from day 4 to day 7. Although simvastatin suppressed mesangial cell proliferation, the increase in the number of glomerular CDK2+/OX-7+ cells was also attenuated by simvastatin treatment. There was no difference in the number of p27Kip1+/OX-7+ cells (p27Kip1-expressed mesangial cells) in the glomerulus between vehicle-treated and simvastatin-treated GN rats. CONCLUSION: Simvastatin suppressed mesangial cell proliferation and subsequent matrix expansion, and macrophage infiltration into glomeruli in anti-Thy 1.1 GN rats. The antiproliferative effect of simvastatin in this model was also associated with the reduction of CDK2 expression in mesangial cells.

Expression of bcl-2 and bax in glomerular disease.

Bcl-2 may account in part for the maintenance of hypercellularity in human glomerular diseases through preventing cell death and by counteracting bax which may be expressed to regulate excessive proliferation. This process is associated with the effect of PDGF B-chain expression. Bax expression may be important in the cell loss leading to glomerulosclerosis and TGF-beta1 participates in this process by increasing bax expression. Thus, the balance of bcl-2/bax expression may be critical in the course of human glomerular diseases.

Simvastatin suppresses glomerular cell proliferation and macrophage infiltration in rats with mesangial proliferative nephritis.

Inhibition of 3-hydro-3-methylglutaryl coenzyme A reductase inhibits the production of mevalonate and has been shown to suppress proliferation in many cell types. Therefore, 3-hydro-3-methylglutaryl coenzyme A reductase inhibitors may have a beneficial effect in glomerular disease, because glomerular cell proliferation is a central feature in the active glomerular injury. This study examines the effect of simvastatin on glomerular pathology in a rat mesangial proliferative glomerulonephritis (GN) induced by anti-thymocyte antibody (anti-Thy 1.1 GN). There was no difference in the degree of the antibody and complement-mediated initial injuries between simvastatin-treated and control GN rats. The most pronounced feature of simvastatin-treated GN was the suppression of the early glomerular cell proliferation. The proliferative activity was maximal at day 4 after disease induction (26.5+/-7.0 of proliferating cell nuclear antigen-positive cells/glomerulus); however, approximately 70% of proliferation was suppressed by simvastatin treatment. At day 4 after disease induction, simvastatin administration also decreased alpha-smooth muscle actin expression in the glomerulus, which is a marker for mesangial cell activation. Inhibition of monocyte/macrophage recruitment into glomeruli by simvastatin was also a prominent feature. There was a 30% decrease in the number of glomerular ED-1+ cells by simvastatin treatment at day 2 after disease induction. Furthermore, simvastatin remarkably suppressed subsequent mesangial matrix expansion and type IV collagen accumulation in glomeruli. We also found that the platelet-derived growth factor expression was reduced in simvastatin-treated nephritic rats, which might simply reflect the reduction in mesangial cell proliferation and mesangial cellularity. There was no significant difference in plasma cholesterol or triglyceride levels between simvastatin- and vehicle-treated nephritic rats at day 2 and day 4, which corresponded to the times when simvastatin treatment resulted in a reduction in mesangial cell proliferation. In conclusion, this is the first report to find that mesangial cell proliferation and matrix expansion have been blocked by simvastatin in vivo. The protective effect of simvastatin in the matrix expansion in anti-Thy1.1 GN was partly by inhibition of mesangial cell proliferation and monocyte/ macrophage recruitment into glomeruli, which were independent of a change in circulating lipids.

Development of a new cellulose triacetate membrane with a microgradient porous structure for hemodialysis.

Dialytic performance and biocompatibility of a newly developed cellulose triacetate (CTA) membrane with a microgradient porous structure, produced without using polyvinylpyrrolidone (PVP) and liquid paraffin, were compared with those of a conventional polysulfone (PS) membrane dialyzer. In vitro and clinical results demonstrated no significant difference in the dialytic performance and biocompatibility of the two dialyzers, but the CTA dialyzer lost less albumin during dialysis than the PS. These results suggest that a CTA membrane dialyzer with a porous microgradient structure attained comparable performance and biocompatibility to PS, and the risk of albumin loss was suppressed by the new CTA membrane.