HIV-related thrombocytopenia: four different clinical subsets.

BACKGROUND

Many factors have been considered in the pathogenesis of HIV-related Thrombocytopenia (HIV-rel TP): immunological destruction, retroviral infection of megakaryocytes and altered reticulo-endothelial function. Nevertheless the pathogenesis is still controversial.

MATERIALS AND METHODS

We reviewed 52 patients (all intravenous drug users) with HIV-rel TP (< 100 x 10(9)/L) by evaluating bone marrow morphology, antiplatelet antibodies (28/52), kinetic studies with 111In Oxine and response to therapy.

RESULTS

Seventeen percent of TP were evaluated as "acute ITP-like", and 40% as "chronic ITP-like"; 35% were evaluated as "pooling" TP and 8% as "hypoplastic" TP. Twenty-four patient with moderate TP (> 30 x 10(9)/L) were followed for a mean time of 27 months and no hemorrhages were seen during the period of observation despite the fact that no treatment was given; twenty-eight others with severe TP (< 30 x 10(9)/L) were treated in different ways: 18% responded to steroids and/or HDIg, 70% to splenectomy and 56% to zidovudine.

CONCLUSIONS

The term "HIV-related thrombocytopenia" should include more than one kind of TP: "Acute ITP-like" TP, "chronic ITP-like" TP, "pooling" TP and "hypoplastic" TP have to be evaluated differently for pathogenesis, clinical manifestations and treatment.