HIV-associated thrombocytopenia

From MedicineWiki

Jump to: navigation, search

Contents

Background

In 1982, Morris et al reported on autoimmune thrombocytopenic purpura in patients at risk of acquired immune deficiency syndrome (AIDS) [1]. Since then, much has been learned about this disorder and its association with the human immunodeficiency virus (HIV). In fact, in the absence of AIDS, the prevalence of thrombocytopenia in HIV-infected individuals ranges from 5-15% and appears to be independent of the clinical or immunological status of the patient [2].

Mechanism of HIV-associated Thrombocytopenia

The exact mechanism of development of thrombocytopenia is still nebulous. HIV-related thrombocytopenia demonstrates both similarities and differences with classical autoimmune thrombocytopenic purpura. It appears that autoantibodies, non-specific immune complexes, and or complement deposition, may all be involved in the etiology of HIV-related thrombocytopenia [3].

Treatment of HIV-associated Thrombocytopenia

The similarity of HIV-associated thrombocytopenia and immune thrombocytopenic purpura (ITP) contributed to the tendency to use corticosteroids as the initial therapy [3]. However, little over half of the patients treated with corticosteroids responded, and their increase in platelet count was not sustained after prednisone was stopped [3]. Because of this disappointing clinical response, poor tolerance of the steroid regimen, and the potential risk of increased immune deficiency, steroids are being increasingly avoided as initial therapy for HIV-related thrombocytopenia [4].

Anti-retroviral therapy with AZT in patients with HIV-associated thrombocytopenia has been noted to result in significant and persistent increase in platelet count [5]. This led to the conclusion that antiretroviral therapy is the treatment of choice for thrombocytopenia related to HIV infection [3].

Intravenous polyvalent high-dose immunoglobulin therapy is usually effective in the treatment of HIV-related thrombocytopenia, with a rapid but transient clinical response [6]. A course of 1-2 grams/kg for 2-5 days usually increases the platelet count to 'safe' levels within 3-8 days [7].

In terms of surgical treatment, splenectomy appears to be associated with excellent initial results, with complete or partial response noted in nearly 86% of patients [3]. In terms of long-term outcomes, complete response was seen in 70% of patients in one study, with 90% of patients remaining asymptomatic after surgery [3]. Splenectomy for HIV-related thrombocytopenia may be associated with increased risk of overwhelming post-splenectomy infection (OPSI). This risk may be decreased by pneumococcal, meningococcal, and hemophilus vaccination [3]. In addition, some authors recommend a prolonged course of prophylactic oral antibiotics in this patient population [3].

Notes & References

[1] Morris L, Distenfeld A, Amorosi E, Karpatkin S. Autoimmune thrombocytopenic purpura in homosexual men. Ann Intern Med. 1982;96:714-717.

[2] Cattaneo R, Rossi G, Carella G, et al. HLA antigens and thrombocytopenia in HIV seropositive subjects. Br J Haematol. 1988;68:268.

[3] Alonso M, Gossot D, Bourstyn E, Galera M-J, Oksenhendler E, Calerier M, Clot P. Splenectomy in human immunodeficiency virus-related thrombocytopenia. Br J Surg. 1993;80(3):330-333.

[4] Schulhafer EP, Grossman ME, Fagin G, Bekk JE. Steroid-induced Kaposi's sarcoma in a patient with pre-AIDS. Am J Med. 1987;82:313-317.

[5] Oksenhendler E, Bierling P, Ferchal F, et al. Zidovudine for thrombocytopenic purpura related to human immunodeficiency virus (HIV) infection. Ann Intern Med. 1989;110:365-368.

[6] Bussel JB, Haimi JS. Isolated thrombocytopenia in patients infected with HIV: treatment with intravenous gammaglobulin. Am J Hematol. 1988;28:79-84.

[7] Oksenhendler E, Bierling P, Farcet JP, et al. Response to therapy in 37 patients with HIV-related thrombocytopenic purpura. Br J Haematol. 1987;66:491-495.

Credits & Notices

Authors-contributors to this page (listed alphabetically, last name, first & middle initial only, no institutional affiliations, no scientific titles):

Stawicki SP

Please make sure you look at the existing references before editing to avoid listing the same citation more than once. The order of references is not important as long as the appropriate reference number in the text points to the correct reference number in the references section.

Personal tools
Toolbox