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A Monteverde

Publications and source records attributed to A Monteverde.

64 records · Page 4Linked to original sources

[Anti-GOR antibodies in type II mixed cryoglobulinemia associated with hepatitis C virus infection].

The frequent association of chronic hepatitic C virus (HCV) infection and type II mixed cryoglobulinemia is considered to be one of the possible signs of interaction between the virus and the immune system. This could also be the case for the appearance of anti-GOR antibodies in serum, as they react with both viral and host antigens. We studied a group of patients with chronic hepatitis C infection and a group with type II mixed cryoglobulinemia associated with HCV infection to ascertain if anti-GOR or other non-organ specific autoantibodies were present in the serum. We found no significant difference between the two groups in presence, prevalence or titer of anti-GOR or other autoantibodies. Moreover, the expression of anti-GOR does not seem to influence the severity of liver damage. Our data support the hypothesis that anti-GOR antibodies are a simple expression of molecular mimicry between viral and human epitopes.

Adult↗

Parenchymal renal involvement in three cases of non-Hodgkin lymphomas: clinical and pathological features.

Parenchymal neoplastic invasion of the kidneys is a common postmortem finding in patients who have died from advanced non Hodgkin's lymphomas (NHL). However, it rarely causes major clinical consequences, such as impairment of glomerular and tubular function, acute or rapidly progressive renal failure. Renal involvement is even less frequent as a first manifestation of NHL, the so-called "primary" renal lymphoma. A review of the main clinical, diagnostic and pathological aspects of three cases observed in our division is presented here.

Acute Kidney Injury↗

A laboratory and thrombokinetic study of HCV-associated thrombocytopenia: a direct role of HCV in bone marrow exhaustion?

OBJECTIVE: In order to investigate HCV associated thrombocytopenia, 6 patients suffering from this disease, in the absence of splenomegaly and other common causes of peripheral platelet destruction, underwent laboratory and scintigraphic tests. RESULTS: Thrombokinetic studies revealed a significant, nearly linear, delayed splenic accumulation with normal or low-normal values for the average platelet life span, low-normal recovery, and depressed platelet production. Megakariopoiesis was normal or slightly increased. HCV infection of the megakariocytes was found in two patients. Autoantibodies and liver disease were also investigated. CONCLUSIONS: A role of immunological mechanisms in HCV associated thrombocytopenia appears to be ruled out. The authors conclude that tests for HCV infection should be included in the evaluation of thrombocytopenia in adults and a possible direct involvement of HCV cannot be excluded.

Aged↗

HCV genotypes in bone marrow and peripheral blood mononuclear cells of patients with mixed cryoglobulinemia.

OBJECTIVE: The association of the hepatitis C virus (HCV) with the cryoglobulinemic syndrome is well known, but its pathogenetic mechanism still remains to be clarified. HCV-RNA has been found in the peripheral blood mononuclear cells (PBMC) of infected subjects. We investigated the presence of the HCV genome in bone marrow cells (BMC), and the distribution of different HCV genotypes in individuals with mixed cryoglobulinemia (MC) and in noncryoglobulinemic controls. METHODS: 15 anti-HCV positive subjects with MC, 7 non-cryoglobulinemic patients with type C chronic active hepatitis (CAH) and 2 anti-HCV negative controls were studied. HCV-RNA was detected by nested PCR of the highly conserved 5'-NCR sequence. HCV typing was carried out by means of the hybridization of the same amplified region with specific probes. RESULTS: HCV-RNA was present in the PBMC of a large proportion of the MC patients and controls without any significant differences. On the contrary, HCV-RNA was present in the bone marrow cells of all the patients with MC and in 43% of the CAH controls. The HCV 1b and 2a genotypes seem to be the most prevalent among MC patients. Nevertheless, the patients with type II MC had a very high prevalence of the 2a genotype (77%). CONCLUSION: The results suggest that the presence of HCV-RNA in bone marrow cells may be correlated to the pathogenetic mechanism of MC. Other studies are needed to confirm the frequent association of HCV genotype 2 with MC.

Aged↗

HCV-RNA detection using different PCR methods in sera, cryoglobulins and peripheral blood mononuclear cells of patients with mixed cryoglobulinemia.

OBJECTIVE: The hepatitis C virus (HCV) is frequently associated with mixed cryoglobulinemia (MC), and a number of authors have reported the presence of anti-HCV antibodies and HCV-RNA in the blood of MC patients. The presence of the HCV genome in the blood cells of individuals infected by HCV may correlate with the etiopathology of MC. We investigated the presence of HCV-related sequences in the sera, cryoglobulins and peripheral blood mononuclear cells (PBMC) of patients with MC and of individuals with type C chronic active hepatitis (CAH). METHODS: 39 patients with MC, 11 non-cryoglobulinemic HCV-positive individuals with CAH, and 2 anti-HCV negative controls were included in the study. The presence of HCV-RNA was detected by nested RT-PCR and by a commercial kit. The PCR was performed by amplifying the 5'-non coding region (5'-NCR) of HCV. RESULTS: HCV-RNA was detected in the sera and cryoglobulins of about 90% of the patients; the commercial kit showed a higher sensitivity than nested PCR. One MC patient showed HCV-RNA only in the cryoglobulins. HCV-RNA was present in the PBMC of 14 of the 20 (70%) MC patients analyzed. No differences in serum and PBMC HCV-RNA positivity were found between MC patients and controls. CONCLUSION: Our results confirm the spread of HCV infection among patients with MC. HCV-RNA is present in the serum, cryoglobulins and PBMC of a large proportion of MC patients. The prevalence of HCV-RNA in the PBMC of MC patients and controls did not differ significantly; this may suggest a tropism of HCV for PBMC regardless of the presence of cryoglobulinemia.

Base Sequence↗

Lymphoproliferation in type II mixed cryoglobulinemia.

OBJECTIVE: The role of the hepatitis C virus (HCV) in the etiology of type II mixed cryoglobulinemia (MC) has been well established, but the pathogenetical relationships among the virus, the immune system, the natural history of MC, and lymphoproliferation in the bone marrow and liver need to be further elucidated. METHODS: Eighty-two patients with HCV positive type II MC and 20 subjects with chronic hepatitis C without MC were studied: bone marrow and liver specimens were examined by routine histology and immunohistochemistry, particularly focusing on parameters related to disease behaviour, such as the expression of the bcl-2 oncogene product and the proliferation-associated Ki67 antigen. RESULTS: In most MC patients there were lymphoid infiltrates within the bone marrow showing a monomorphic cytology, frequent immunoglobulin light chain monotypic restriction, expression of the anti-apoptotic bcl-2 oncogene product, and a low proliferative capacity (Ki-67 < 3%). On the other hand, in all non-cryoglobulinemic patients a bone marrow picture of reactive lymphoplasmacytosis was found. In both MC and chronic hepatitis patients, the liver biopsy showed portal infiltrates consisting of T-cells, associated with a significant B-cell component; the latter was particularly abundant in MC, where it was frequently arranged in pseudo-follicles. The B-cell component expressed the bcl-2 oncogene product and CD5 antigen, thus suggesting that the immune system is actively involved in the production of liver damage both in MC and non-cryoglobulinemic patients. It is worth noting that in MC patients (but not in the non-cryoglobulinemic patients) these CD5+/bcl-2+ B-cells frequently also exhibited a monotypic restriction bearing an IgM kappa. CONCLUSION: Our findings in these liver and bone marrow studies further support the role of a lymphoproliferative disorder in the pathology of type II MC: the B cells involved accumulate due to the inhibition of apoptosis, and their low proliferative index justifies the indolent course of the disease. HCV probably interacts with these B-cells, facilitating their clonal expansion.

Adult↗

GISC protocol experience in the treatment of essential mixed cryoglobulinaemia.

OBJECTIVE: We compared the efficacy of interferon and deflazacort in the treatment of the cryoglobulinaemic syndrome and assessed the usefulness of adding a low antigen diet to drug therapy. METHODS: We studied 63 patients randomly allocated to different groups who underwent clinical and laboratory examinations every two months and who received treatment for 12 months or until a significant clinical event appeared. RESULTS: Five of 28 patients treated with interferon showed clinical improvement whereas 4 worsened and 7 suffered untoward side effects; seven of 28 patients treated with deflazacort improved, 4 worsened and 4 suffered drug toxicity. Twenty-nine patients were assigned to combined low antigen diet and therapy, among whom 7 did not follow the diet, 5 improved and 2 worsened. Among the 34 patients who were on an unrestrained diet, 5 improved and 7 worsened. None of the treatments proved superior to the others. CONCLUSION: Our results do not confirm the suggestion that interferon should be the primary therapy in the treatment of the cryoglobulinaemic syndrome, and the usefulness of a low antigen diet seems minimal.

Adult↗

A pilot study on the effectiveness of cyclosporine in type II mixed cryoglobulinemia.

OBJECTIVE: To evaluate the effect of cyclosporine in the treatment of type II mixed cryoglobulinemia, after the failure of more conventional therapies. METHODS: Two patients with type II mixed cryoglobulinemia associated with chronic HCV infection, purpura, liver disease, and sensitive/motor neuropathy were treated with cyclosporine (2.5 mg/Kg/b.w.), after their failure to respond to treatment with corticosteroid, immunosuppressive drugs, interferon, and plasmapheresis. RESULTS: In both patients an improvement in the clinical manifestations (purpura and peripheral neuropathy), laboratory results (serum transaminases and cryocrit), and liver histology was seen, as well as the disappearance of bone marrow B-cell lymphoproliferation. CONCLUSION: Cyclosporine may be useful in the treatment of type II mixed cryoglobulinemia with prominent autoimmune clinical manifestations, although further studies are needed to better define the selection of patients.

Antirheumatic Agents↗

[Lipid metabolic disorders in obesity: their epidemiology, physiopathology and clinico-therapeutic implications].

The centralization of body fat, particularly in abdominal or visceral depots, is associated with qualitative and quantitative lipid abnormalities. Examples of these qualitative alterations include changes in low density lipoprotein composition, namely an increased number of small or dense low density lipoprotein particles, which seem to be prone to increased lipid oxidation. Oxidative modification of low density lipoproteins is involved in atherosclerotic development of the arterial wall. Alterations of lipid composition often arise in a context of insulin resistance with hyperinsulinism. Genetic features, such as apolipoprotein E polymorphism, also play a significant role in lipoprotein metabolism. The principle treatment of obesity and associated dyslipidemia is to reduce energy intake through diet. Moderate exercise is effective, especially in patients with insulin resistance. Drug therapy is considered primarily for patients who refuse to make behavioral changes.

Humans↗