Platelet-associated IgM elevated in patients with chronic hepatitis C contains no anti-platelet autoantibodies

Platelet autoantibodies are common in hepatitis C infection, irrespective of the presence of thrombocytopenia

OBJECTIVE

To investigate the generation of platelet antibodies in hepatitis C virus (HCV)-infected individuals and their relation to the development to thrombocytopenia with the aim of using their detection as a diagnostic aid of immune thrombocytopenia in these patients.

MATERIALS AND METHODS

We tested by the monoclonal antibody-specific immobilization of platelet antigen assay (MAIPA) for the presence of platelet antibodies against specific glycoprotein (GP) targets (GPIIb/IIIa, GPIb/IX, GPIa/IIa, GPIIIb, GPV, and FcRgammaIIa) in 48 HCV-infected individuals of various stages of disease and compared the results with those from 35 patients with alcoholic liver cirrhosis.

RESULTS

Thirty-two HCV-infected individuals (66%) had detectable platelet antibodies. The most common target was GPIIb/IIIa, but all other GP were also targets. Results were not different from patients with alcoholic liver cirrhosis. There was no correlation between antibodies and platelet counts, or the stage of disease, or the viral genotype, or a discernible influence of treatment with alpha-interferon.

CONCLUSION

While platelet autoantibodies are common in individuals with HCV infection, their detection does not assist in the diagnosis of immune thrombocytopenia.

Autoimmune thrombocytopenia in response to splenectomy in cirrhotic patients with accompanying hepatitis C

AIM: To estimate the contribution of autoimmune thrombocytopenia to hepatitis C virus-related liver cirrhosis (type C cirrhosis), we evaluated the influence of splenectomy upon platelet-associated immunoglobulin G (PAIgG) levels and platelet numbers.

METHODS: PAIgG titers and immune markers were determined in 24 type C cirrhotic patients with an intact spleen, 17 type C cirrhotic patients submitted to splenectomy, and 21 non-C cirrhosis with an intact spleen.

RESULTS: Thrombocytopenia (PLT<15×10⁴/μL) in type C cirrhosis was diagnosed in all patients with an intact spleen, 8 patients submitted to splenectomy, and in 19 non-C cirrhosis with intact spleen. Elevated titers of PAIgG at more than 25.0 ng/10⁷cells were detected in all cirrhotic patients except for one splenectomized patient. PAIgG titers (ng/10⁷cells) were significantly higher in the type C cirrhosis with an intact spleen (247.9 ± 197.0) compared with the splenectomized patients (125.6±87.8) or non-C cirrhosis (152.4 ± 127.4). PAIgG titers were negatively correlated with platelet counts in type C cirrhotic patients with an intact spleen. In comparison with the type C cirrhosis with an intact spleen, the splenectomized patients had a reduced CD4/CD8 ratio and serum neopterin levels. The spleen index (cm²) was negatively correlated with platelet counts in the non-C cirrhosis, but not in the type C cirrhosis.

CONCLUSION: Our data indicate that the autoimmune mechanism plays an important role in thrombocytosis complicated by HCV-positive cirrhosis. In addition, splenectomy may impair T cells function through, at least in part, a reduction of CD4/CD8 ratio, consequently suppressing PAIgG production.

Improvement of thrombocytopenia with disappearance of HCV RNA in patients treated by interferon-alpha therapy: possible etiology of HCV-associated immune thrombocytopenia

We evaluated the relationship between the severity of thrombocytopenia and the serum hepatitis C virus (HCV) RNA level to investigate the mechanism of thrombocytopenia in patients with HCV infection. Patients who had chronic hepatitis without splenomegaly were divided into two groups according to the platelet count, which were 18 patients with a platelet count < or =150 x 10(9)/L and 22 patients with a platelet count >150 x 10(9)/L. HCV RNA, platelet-associated immunoglobulin G (PAIgG), rheumatoid factor (RF), and other immunological parameters were measured and correlations were investigated. Patients in the low platelet group had higher levels of PAIgG, Th1 cells, thrombopoietin (TPO), and RF than those in the normal platelet group (textitP < 0.05). Twenty-two patients completed 6 months of IFN therapy and were followed for more than 1 yr afterwards. Twelve patients who responded to IFN therapy with clearance of HCV showed an increase of the platelet count, whereas the 10 patients who did not respond to IFN showed a decrease of the platelet count. The improvement of thrombocytopenia after interferon therapy suggests a contribution of HCV infection to this condition.

Hepatitis C virus-related thrombocytopenia: clinical and laboratory characteristics compared with chronic immune thrombocytopenic purpura

Thrombocytopenia can be a complication of hepatitis C viral (HCV) infection. However, there is little published data regarding the clinical and laboratory manifestations of HCV-related thrombocytopenia (HCV-TP) compared with adult chronic immune thrombocytopenic purpura (CITP). We reviewed the medical records for all patients evaluated for chronic thrombocytopenia by the Haematology Service between January 1996 and June 2000. All patients were screened for HCV infection at the time of initial diagnosis. Of 250 patients who fulfilled American Society of Hematology criteria for CITP, 76 (30%) were HCV seropositive. HCV-TP patients were older [mean age (+/-SD) 54.9 +/- 8 years vs. 40.3 +/- 8 years, P </= 0.001] and equally distributed between both sexes. HCV-TP patients had less severe thrombocytopenia, defined as platelet count </=10 x 10(9)/l (4% vs. 46% for CITP, P </= 0.001). However, 56 (74%) had a platelet count </=50 x 10(9)/l. Symptoms and signs of thrombocytopenia were less frequent in HCV-TP, but major bleeding was more frequent (25% vs. 10%, P = 0.0059). Serum cryoglobulins and anticardiolipin antibodies were more frequent in HCV-TP (90% and 62% respectively), but rare in CITP (7% and 15%, P </= 0.001 compared with HCV-TP). HCV infection can be associated with significant thrombocytopenia and appears to be a distinct clinical entity.

Combination therapy with pegylated interferon plus ribavirin in the treatment of hepatitis C virus-related thrombocytopenia

BACKGROUND

Isolated thrombocytopenia is a common manifestation of hepatitis C virus (HCV) infection. There is no established treatment modality for this condition. The efficacy of standard interferon (IFN) monotherapy has been reported in some studies. The major disadvantage of this treatment is the high rate of recurrence due to viral breakthrough during the first 12 weeks of treatment. Pegylated IFNs are now the standard regimen for chronic hepatic disease due to HCV infection. However, due to a lack of evidence, pegylated IFNs are not widely used for HCV-related isolated thrombocytopenia.

OBJECTIVE

The aim of this report was to present the case of a male patientwith severe symptomatic thrombocytopenia due to HCV infection.

METHODS

Thrombocytopenia was treated with pegylated IFN plus ribavirin.

RESULTS

Although standard IFN monotherapy failed to achieve virologic and hematologic improvement, therapy with pegylated IFN alfa-2a plus ribavirin was associated with both virologic and hematologic improvement without any significant adverse effects.

CONCLUSIONS

Pegylated IFN plus ribavirin was effective in this patient for thetreatment of HCV-related thrombocytopenia. However, further research is needed to define the response rate in different patient populations.

Treatment of hepatitis C related thrombocytopenia with interferon alpha

Thrombocytopenia is a common extrahepatic manifestation of hepatitis C (HCV) infection. Treatment with steroids may be effective, but can exacerbate the viral infection. Interferon alpha (INF) has documented efficacy in the treatment of HCV, but its use in the treatment of HCV thrombocytopenia is controversial. We treated eight patients with HCV-related thrombocytopenia, who had platelet counts of fewer than 50 x 10(9)/l (range: 16 to 46 x 10(9)/L) with INF 3 MU SQ three times a week. Planned duration of treatment was 24 weeks. Five patients had no evidence of hepatic cirrhosis, three had cirrhosis, and two had palpable splenomegaly. Only three patients tolerated the full course of treatment, and all three had improvement in their platelet counts to greater than 50 x 10(9)/l. Two other patients had improvement in platelet counts to more than 50 x 10(9)/l with shorter duration of treatment (six and 16 weeks, respectively). The mean increase in platelet count in the five responders was 44 x 10(9)/lL (range: 28 to 90 x 10(9)/l). The average peak platelet count in the responders was 81 x 10(9)/l (range: 62 to 136 x 10(9)/l). Duration of response ranged from four to 18+ months, with the shortest responses observed in the two patients treated with a shorter course of INF. Response was independent of the presence of cirrhosis. Responding patients had improvement in hepatic transaminases, reduction in cryoglobulin and anticardiolipin antibodies, and HCV plasma RNA when tested. Relapse was associated with an increase in these laboratory markers of HCV infection. We conclude that INF can be an effective treatment in patients with HCV-related thrombocytopenia.

HCV-associated thrombocytopenia: clinical characteristics and platelet response after recombinant alpha2b-interferon therapy

Hepatitis C virus (HCV) has been proposed as a possible causative agent of chronic thrombocytopenia. We investigated HCV infection in a series of 51 unselected Spanish patients with chronic acquired thrombocytopenia. Anti-HCV and HCV viraemia were detected in 13/51 (22.5%) of cases; this prevalence was particularly significant when compared with HCV seropositivity in age-matched controls (0.4%). Anti-HCV-positive patients, four men and nine women with a median age of 59.3 years (range 36-72), had a mean platelet count of 55.8 x 109/l (range 12-96). Only one of our HCV-positive thrombocytopenic patients had hypersplenism. Platelet-associated IgG (PAIgG) was negative, as measured by immunofluorescent flow cytometric analysis in 11/13 HCV-positive thrombocytopenic patients. Thus, thrombocytopenia in our HCV-positive patients appeared to be non-autoimmune mediated. In six patients, a trial of recombinant alpha2b-interferon (IFN-alpha) given at a dose of 3 MU three times per week for 6-24 months gave a durable (> 1 year) and significant increase in platelet count in all six patients. The maximum increase occurred after 6 months of IFN-alpha therapy. In conclusion, the ability of IFN-alpha to increase platelet counts in HCV-positive thrombocytopenic patients supports mechanisms involving a direct role for HCV inhibiting platelet production.