Reduction in the presence of cryoglobulins over time in the hemodialysis treatment.

BACKGROUND: The presence of cryoglobulins in patients with chronic kidney disease (CKD) on hemodialysis is well described. However, the generation of cryoglobulins during the dialysis treatment has yet to be established. The aim of the present study was to determine the presence of serum cryoglobulins over time in the dialysis treatment in patients with CKD not infected with hepatitis C virus (HCV). METHOD: Peripheral blood samples were collected at the beginning of dialysis treatment and at 30, 60, 90 and 120 days afterwards. Cryoglobulins were defined by the presence of immunocomplexes that precipitated in vitro with exposure to cold and resolubilized when rewarmed. The components of the cryoprecipitate were analyzed by radial immunodiffusion. RESULTS: In this study, 14 patients were included: 11 male and three female, aged 28-88 years, with mean time on hemodialysis of 57 ± 36 days at baseline. The presence of cryoglobulin, constituted by IgM, IgA, IgG and the C3 and C4 components of the complement, was observed in the serum of all patients at the beginning of hemodialysis. Sequence analyses showed that the amount of cryoprecipitate decreased during the dialysis treatment. CONCLUSION: There was a high prevalence of mixed cryoglobulins in CKD patients at the beginning of hemodialysis, and the amount of cryoprecipitate decreased during the treatment.

Evaluation of neutrophilic activity in patients submitted to kidney transplantation.

BACKGROUND: Cryoglobulinemia is frequent in renal transplant patients. The mononuclear and polymorphonuclear neutrophil (PMN) phagocytic systems are important for the clearance of cryoglobulin immune complexes. There might be a reduced phagocytic activity in transplant patients with cryoglobulinemia (CRYO+). METHODS: We studied the phagocytic activity by PMNs, in the presence of immune complexes in renal transplant patients, with or without hepatitis C virus (HCV) infection. Thirty-seven patients subjected to kidney transplant were evaluated, and for the control group, healthy blood donors were chosen. The presence of cryoprecipitate was evaluated, as well as HCV infection, phagocytic activity by neutrophils during the ingestion and digestion phase. RESULTS: The presence of cryoprecipitate was detected in 75.7% of the patients, 39.28% of which had HCV infection. IgG, IgM, IgA, and C3 and C4 complement components were identified in the cryoprecipitate. There was a reduction in the ingestion phase of phagocytosis by PMNs in renal transplant CRYO+ though the digestion phase was preserved. CONCLUSION: We concluded that there was a decreased PMN activity in transplanted patients presenting cryoglobulinemia.

Avaliação imunológica na endocardite infecciosa / Immunologic evaluation in infective endocarditis

OBJECTIVE: To analyze the immune response in peripheral blood of patients with infective endocarditis. METHODS: We studied 10 patients with infective endocarditis, age range from 20 to 50 years-old, males and females, and 20 healthy subjects in the same age range. The diagnosis of the disease was based on the clinical picture, echocardiogram, and hemoculture based upon samples drawn and tested before the treatment started. The were no history of atopy or malnutrition, no autoimmune disease, and they were not using any immunosuppressant or antibiotic medication. RESULTS: The patients with endocarditis had significantly higher T and B lymphocyte, CD4+ and CD8+ cell counts, IgM and IgG serum levels, and C4 component of the complement than the control group; no significant difference concerning serum IgA and neutrophil oxidative metabolism; a significant decrease in C3, chemotaxis, and monocyte phagocytosis;cryoglobulins were detected in 66.6 percent of patients and they were formed by IgG, IgM, IgA, C3, and C4. CONCLUSION: The patients with infective endocarditis were immunocompetent in most sectors of immune response and, at a certain moment, an autoimmune component may be present

Ocurrencia de crioglobulinemia en donantes de sangre del Hospital Universitario de Caracas con Hepatitis C confirmada: relación clínico epidemiológica / Occurence of cryoglobulinemia in blood donors of Hospital Universitario de Caracas with C viral hepatitis confirmed: clinical epidemiology relation

Debido a la fuerte asociación entre crioglobulina mixta (CM) y virus de hepatitis C (VHC) reportada entre 36-98 por ciento y con el objeto de investigar esta situación en población asintomática, en nuestro estudio determinamos la ocurrencia de crioglobulinas en donantes del banco de sangre con VHC confirmado. Estudiamos 62 donantes, divididos en tres grupos: grupo A:ELISA (enzyme-linked immunobsorvent assay) II-III positivo, RIBA (recombinant inmunoblot assay) 2.0 positivo; grupo B:ELISA positivo, RIBA negativo; grupo C:ELISA negativo. A los tres grupos se les determinó crioglobulinas y se tipificaron las positivas (valor positivo mayor de 0,5 mg/ml), al mismo tiempo ALT, AST (valor positivo mayor de 50 UI) y GGt (valor positivo mayor de 32 UI en mujeres y mayor de 50 UI en hombres). Crioglobulinas positivas estuvo presente en 10/13 del grupo A, 1/17 del grupo B y 8/32 del grupo C. Encontreamos:grupo A Vs B (p=0,00009049 por Fisher; y a Vs C (X²= 10,38; df=1; p=0,000127). La tipificación mostró predominio de inmunoglobulina G en el grupo A: 10/10, y sólo 1/8 del grupo C. No hubo relación entre elevación de aminotransferasas y GGt con crioglobulinas positivas. Los promedios más altos de aminotrasferasas y crioglubulinas se apreciaron en el grupo A. La ocurencia de VHC en el banco de sangre del Hospital Universitario de Caracas fue de 0,46 por ciento anual por método de ELISA. La infección por VHC está asociada con crioglobulinas positivas aún durante el período asintomático y no como manifestación tardía, sin que éstas tengan relación con aminotrasferasas elevadas

Cryoglobulinemia and cutaneous vasculitis in human brucellosis.

We report the occurrence of cryoglobulinemia and cutaneous vasculitis in three patients with brucellosis caused by Brucella melitensis. The isolated cryoglobulins were characterized as mixed polyclonal or type III. Brucella agglutinin activity was not detected in any of the cryoglobulins analyzed. However, the same agglutinin titer and the presence of precipitin lines of identity in immunodiffusion gels were observed in the supernatant of the cryoglobulins and the serum. Rheumatoid-factor activity was present in all the cryoprecipitates tested. Resolution of the purpuric lesions with therapy coincided with a decrease in serum cryoglobulins and, in one patient, with normalization of his serum C3 levels. These findings suggest that the immunological abnormalities manifested by our patients were the direct consequence of the brucellosis infection and provide additional evidence to support the role for immunological mechanisms in the pathogenesis of human brucellosis.

Characterization of proteins, insoluble at low temperature, produced by Clostridium botulinum type C and C. subterminale. Their antigenic relationship with a similar protein synthesized by C. botulinum type G.

The production of a protein insoluble at low temperature ("cryoprotein"), by cultures of Clostridium botulinum type G has been shown to be a metabolic characteristic also shared by C. botulinum type C and by C. subterminale. These new cryoproteins have been purified and some of their chemical and immunological properties studied. It was found that both proteins were chemically very similar among themselves and to the cryoprotein isolated from C. botulinum type G. All these proteins are formed by a single polypeptide chain of approximately Mr = 180,000, with closely related amino acid compositions, isoelectric points and do not contain either free cysteine or disulfide bridges. Homologous and heterologous radioimmunoassays established the existence of an antigenic similitude among the cryoproteins from C. botulinum type G and C. subterminale thus becoming the first purified antigens which relate both bacterial species. If the production of cryoproteins can be shown to be a generalized phenomenon within the genus Clostridium these substances would provide an important tool to examine immunological and genetical relatedness between strains in this bacterial group.

PMN chemotactic inhibition associated with a cryoglobulin.

A child with recurrent pyogenic infections, eczema, markedly elevated serum concentrations IgA, and totally absent PMN chemotactic acticity is described. The chemotactic defect was characterized as a humoral inhibitor present in serumand plasma, directed toward autologous as well as homologous PMN's. Immunochemical studies revealed the purified inhibitor to be a cryoglobulin composed of an IgM-IgA complex. Incubation of the cryoglobulin complex with PMN's resulted in a quantitative dose-response curve.