Glomerulopathies of dysproteinemias, abnormal immunoglobulin deposition, and lymphoproliferative disorders

Long-term outcome of kidney transplantation in patients with fibrillary glomerulonephritis or monoclonal gammopathy with fibrillary deposits

To determine the outcome of kidney transplantation in patients with fibrillary glomerulonephritis (FGN), a rare glomerular disease, we followed 12 patients, 5 with FGN and 7 patients with monoclonal gammopathy and fibrillary deposits (MGFD), who underwent 15 kidney transplants since 1988 with a median follow-up of 52 months. Recurrent disease did not arise in any of the patients with FGN but developed in 5 patients with MGFD. Seven allografts failed: 1 in the FGN group and 6 in the MGFD group. Median allograft survival for patients with MGFD was 37 months but had not been reached in FGN patients. One patient with FGN had primary allograft failure secondary to graft thromboembolism. Three patients with MGFD were re-transplanted and one lost the second allograft to recurrent disease, but the other two died from hematological malignancy. Another patient was diagnosed with MPGN type III and did not have detectable fibrillary material 22 months after transplantation. One patient with MGFD had stable allograft function 6 months post-transplant but another, with recurrent disease, underwent peripheral blood stem cell transplantation and regained stable allograft function. Our study shows that kidney transplantation appears safe in patients with FGN with little risk of recurrence. However, patients with MGFD have a significant risk for disease recurrence. Whether the development of hematological malignancies following transplantation in this group is related to their original disease or was coincidental requires further studies.

A proliferative glomerulonephritis secondary to a monoclonal IgA

A distinct entity mimicking immune-complex-mediated glomerulonephritis characterized by a proliferative glomerulonephritis with monoclonal immunoglobulin G (IgG) deposits recently was described. We now report a case of a 35-year-old woman who presented with sudden onset of edema, proteinuria, hematuria, and hypertension. Renal biopsy showed diffuse endocapillary proliferation, mesangial cellularity, and amorphous material in the mesangium. Immunofluorescence examination showed mesangial and capillary wall staining for IgA (2+), C3 (2+), fibrinogen (2+), and lambda (2+). Congo red stain was negative. Electron microscopy showed mesangial and subendothelial deposits with a paracrystalline lattice-like substructure forming parallel linear arrays. Extensive laboratory evaluation showed a small population of monoclonal plasma cells with lambda restriction. The present case suggests that monoclonal IgA deposits also can cause proliferative glomerulonephritis. However, the presence of paracrystalline deposits in association with monoclonal IgA deposits has not been described previously.

Regulatory effects of novel neurotrophin-1/b cell-stimulating factor-3 (cardiotrophin-like cytokine) on B cell function

We describe regulatory effects that a novel neurotrophin-1/B cell-stimulating factor-3 (NNT-1/BSF-3; also reported as cardiotrophin-like cytokine) has on B cell function. NNT-1/BSF-3 stimulates B cell proliferation and Ig production in vitro. NNT-1/BSF-3-transgenic mice, engineered to express NNT-1/BSF-3 in the liver under control of the apolipoprotein E promoter, show B cell hyperplasia with particular expansion of the mature follicular B cell subset in the spleen and the prominent presence of plasma cells. NNT-1/BSF-3-transgenic mice show high serum levels of IgM, IgE, IgG2b, IgG3, anti-dsDNA Abs, and serum amyloid A. NNT-1/BSF-3-transgenic mice also show non-amyloid mesangial deposits that contain IgM, IgG, and C3 and are characterized by a distinctive ultrastructure similar to that of immunotactoid glomerulopathy. NNT-1/BSF-3-transgenic mice produce high amounts of Ag-specific IgM, IgA, and IgE and low amounts of IgG2a and IgG3. Normal mice treated with NNT-1/BSF-3 also produce high amounts of Ag-specific IgE. NNT-1/BSF-3 regulates immunity by stimulating B cell function and Ab production, with preference for Th2 over Th1 Ig types.

Management of renal complications in patients with advanced multiple myeloma

Although the kidney is frequently involved in malignant monoclonal gammopathy, the clinical outcome of the patients varies considerably. We retrospectively assessed the clinical course in seventeen patients with acute and chronic renal failure suffering from multiple myeloma, and analyzed their case history focusing on the therapeutic management, the possible clinical improvement as well as the patients' outcome. Treatment included chemotherapy (n = 17), forced diuresis (n = 3), hemodialysis (n = 11, 7 chronic, 4 intermittent) and plasmapheresis (n = 3). Renal function improved in five patients, and was stabilized compensated in four. Seven patients developed end-stage renal disease, one refused further treatment and was lost for follow up. In addition to renal failure, the most frequent complications included local bone destruction (all), anemia (n = 12), low platelet count (n = 11), and bacterial infections (n = 9). One year survival rate after admission to the nephrology department was 76 percent. Chemotherapy in combination with renal replacement therapy may improve the clinical course even in MM patients with serum creatinine levels above 3.0 mg/dL or end-stage renal disease.

The primary glomerulopathies

Disorders of glomerular structure and function are encountered frequently in clinical medicine. Many arise as part of a well-defined multisystem or multi-organ disease process, while in others the clinical and laboratory manifestations are consequent to the sole or predominant involvement of glomeruli. The latter are known as the primary glomerulopathies. These disorders can evoke a variety of clinical syndromes, including acute glomerulonephritis, rapidly progressive glomerulo-nephritis, nephrotic syndrome, "symptomless" hematuria and/or proteinuria, and chronic glomerulonephritis. The identification of underlying morphology, through the application of renal biopsy techniques, can provide useful information for both prognosis and treatment. Pathogenic mechanisms involved in the primary glomerulopathies are varied, but immunologic perturbations underlie many disease entities. This article describes the clinical features, pathology, natural history, and treatment of the main categories of primary glomerulonephritis, with emphasis on recent developments and practical aspects of diagnosis and management.