Immune Thrombocytopenic Purpura Associated With Hepatitis C Virus

Abstract

Introduction:  Immune thrombocytopenic purpura (ITP) is a frequent cause of thrombocytopenia, especially in children. It can be Idiopathic or secondary to their diseases. The commonest cause of thrombocytopenia in Chronic Liver Disease has been reported to be platelet pooling and destruction in the spleen. The aim of the present study was to investigate the fre-quency of thrombocytopenia in Anti-HCV+ve patients excluding patients who had progressed to CLD.

Materials/Methods:  Thrombocytopenia (<150,000/uL) was diagnosed in 60 (20%) out of 300 patients of Anti-HCV+ve status. Bone marrow examination (aspirate +trephine biopsies) was subsequently done on which the adequacy of megakaryo-cytes was noted.

Results:  The ages of the patients ranged from between 18-65 years with an equal male to female ratio. Patients who had had splenomegaly were excluded to rule out Hypersplenism as a cause of Thrombocytopenia. Bone marrow biopsy showed ade-quate/increased megakaryocytes in 41 (68%) patients.

Conclusion:  HCV infection is strongly associated with thrombocytopenia and may produce significant peripheral destruc-tion of platelets related to autoimmune mechanisms.

Background:  There has been an association between Hepatitis C virus infection and the development of autoimmune diseases in several studies conducted to date.¹ Autoantibodies against platelet membranes can also develop in Hepatitis C infection. These antibodies are involved in the pathogenesis of Immune thrombocytopenic purpura. The antibodies coating the platelet membranes result in the splenic sequestration and phagocytosis of the platelets by macrophages. Hence thrombo-cytopenia in Immune Thrombocytopenic Purpura is caused by the reduced lifespan of the platelets in circulation alongwith incomplete compensation by the bone marrow megakaryocytes.² The diagnosis of Immune thrombocytopenic Purpura can only be established if other causes of thrombocytopenia such as Leukemia, Myelophthisic bone marrow infiltration Myelo-dysplasia, Aplastic anemia adverse drug reactions have been excluded.³ The estimated annual incidence of Immune Throm-bocytopenic Purpura is approximately 5 cases per 100,000 Children and  2 cases per 100,000 adults.⁽⁴ Hepatitis C is endemic in Pakistan. The estimated prevalence of Hepatitis C in Pakistan ranges from 5 to 8%.⁵ Most recently, there, there has been emerging evidence that Immune thrombocytopenic Purpura is a frequent cause of thrombocytopenia in Hepatitis C virus infection.⁶ So In a country hyperendemic for hepatitis C like Pakistan this association might even be more significant. Thrombocytopenia in Hepatitis C can result from number of causes: 1. Hypersplenism. 2. Aplastic bone marrow associated with Hepatitis C. 3.Dysregulation of host Immune mechanisms.⁷

Key Words:  Immune thrombocytopenic purpura, Hepatitis C.