Serum immunoglobulins in the nephrotic syndrome. A possible cause of minimal-change nephrotic syndrome

Non-specific immunity in nephrotic syndrome

In order to explain susceptibility to bacterial infection in patients with nephrotic syndrome, bactericidal capacity of polymorphonuclear neutrophils (PMN) and serum opsonic activity were studied. The groups consisted of 29 patients and 29 controls. Bactericidal capacity was found to be statistically significant defective in the patient group when compared with controls for Staphylococcus aureus and Excherichia coli. Serum opsinic activity was found to be defective in up to 50% of the patients, but it was not statistically significant for either bacteria. There is no correlation between the impairment of bactericidal capacity and serum total protein, albumin, globulin, total lipid, cholesterol, age of patients and the duration of the illness. When bactericidal capacity was examined in five patients in remission it had returned to the normal level. The results of this study suggest that bactericidal capacity and possibly serum opsonic activity are influenced by the nephrotic syndrome.

Severe steroid-responsive nephrosis associated with hypersensitivity

Sensitivity to cow's whole milk investigated in six patients with the idiopathic nephrotic and an elemental diet was given. After proteinuria had decreased to less than or equal to 500 mg/24 hours on consecutive days patients were challenged with cow's milk. This resulted in the return of significant proteinuria, oedema, and decreased urine volume together with a decrease in serum-IgG concentrations in four patients. Acute alteration of plasma C3 complement component accompanied milk challenge in all 6 patients. There were no consistent alterations in other immunoglobulin concentrations. Intradermal skin testing with cow's milk extract was positive in all patients. These results suggest that in some individuals clinical and biochemical manifestations of the nephrotic syndrome of childhood may be related to hypersensitivity of food products.

Quantitative change of serum protein and immunoglobulin in patients with solid cancers

There are many quantitative changes of serum protein and immunoglobulin fractions in patients with cancer of various sites, excluding those with leukemic and lymphoproliferative disorders. The commonest change in serum proteins of patients with neoplastic disease is a reduction in albumin concentration and elevation of alpha globulins, especially alpha-2 fraction. Immunoglobulins (IgG, A,M) are a heterogenous group of proteins contained in the gamma, beta, and alpha-2 electrophoretic fractions of serum proteins. The IgG was found to be significantly increased in patients with cancer of the skin and lung, but decreased in patients with cancer of the prostate and breast. Serum IgM was reported to be elevated in patients with sarcoma, melanoma, brain tumors, but decreased in patients with carcinoma of the ovary. Serum IgA was found to be elevated in patients with cancer of epithelial secretory organs, such as skin, breast, head and neck, lung, gut, prostate, and uterine cervix. Whether these findings reflect specific changes of the humoral arm of tumor-host interaction remains to be investigated.

The nephrotic syndrome associated with neoplasia: an unusual paraneoplastic syndrome. Report of a case and review of the literature

The nephrotic syndrome complicating malignancy in the absence of renal vein thrombosis, amyloid or neoplastic infiltration of the kidney is an unusual occurrence. A case of diffuse, well differentiated, lymphocytic lymphoma and lipoid nephrosis documented by light microscopy, electron microscopy and immunofluorescent studies is reported. A review of the literature revealed 76 case reports in which the nephrotic syndrome was associated with neoplasia. The most frequently associated neoplasms are Hodgkin's disease, various carcinomas, nonHodgkin's lymphoma and leukemia in descending order. The most frequent renal lesion in patients with the nephrotic syndrome associated with various carcinomas is membranous glomerulonephritis (81 per cent) as opposed to patients with lymphomas or leukemias who have predominantly lipoid nephrosis (60 per cent). The evidence is reviewed suggesting that the lesions in membranous nephropathy are immunologically mediated by tumor or viral antigen-antibody complexes and in lipoid nephrosis perhaps by a defect in t-lymphocyte function.

Inhibition of lymphocyte blastogenesis by plasma of patients with minimal-change nephrotic syndrome

Plasma from 7 patients with minimal-change nephrotic syndrome (M.C.N.S.) (lipoid nephrosis) confirmed by renal biopsy inhibited the blastogenic response of lymphocytes to the mitogen phytohaemagglutinin (P.H.A.) and to allogeneic lymphocytes in mixed lymphocyte culture. Plasma from 14 patients with nephrotic syndrome due to other glomerular diseases did not have this effect. 5 of the 7 patients with M.C.N.S. achieved remission; 4 with prednisone and 1 spontaneously. While in remission, plasma from these 5 patients no longer inhibited the response of lymphocytes to P.H.A. These findings suggest a pathogenic relation between M.C.N.S. and cell-mediated immunity.