Two autoantibodies indicate different thrombocytopenia phenotypes

Kuwana M _ et al_. (2006) Two types of autoantibody-mediated thrombocytopenia in patients with systemic lupus erythematosus. _Rheumatology_ 45: 851–854 A common mechanism of thrombocytopenia

in systemic lupus erythematosus (SLE) is believed to be increased platelet clearance by autoantibodies. Autoantibodies to two platelet-specific antigens—thrombopoietin receptor (TPOR) and

glycoprotein IIb/IIIa (GPIIb/IIIa)—have been implicated in SLE-associated thrombocytopenia. Kuwana _ et al_. have conducted a new study that explored the roles of these two autoantibodies.

The study included 32 SLE patients with thrombocytopenia, 30 SLE patients who had never been thrombocytopenic, 92 patients with idiopathic thrombocytopenia, and 60 healthy individuals. All

patients were tested for autoantibodies to TPOR and GPIIb/IIIa, and the megakaryocyte density of the bone marrow of patients with thrombocytopenia was also evaluated. Laboratory tests showed

that autoantibodies to both TPOR and GPIIb/IIIa were significantly more common in patients with thrombocytopenia than in patients without (_P_ <0.0001 and _P_ = 0.01, respectively);

levels did not differ between SLE patients with thrombocytopenia and patients with idiopathic thrombocytopenia. Overall, 91% of the SLE patients with thrombocytopenia had at least one of the

two autoantibodies. Autoantibodies to TPOR and GPIIb/IIIa were associated with different phenotypes of thrombocytopenia: SLE patients with autoantibodies to TPOR showed megakaryocytic

hypoplasia and a worse response to treatment than SLE patients with autoantibodies to GPIIb/IIIa, who showed normal or high megakaryocyte density. The authors suggest that tests for these

autoantibodies might be useful to distinguish between subsets of patients with SLE-related thrombocytopenia, and could help predict their responses to therapy. RIGHTS AND PERMISSIONS

Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Two autoantibodies indicate different thrombocytopenia phenotypes. _Nat Rev Rheumatol_ 2, 523 (2006).

https://doi.org/10.1038/ncprheum0281 Download citation * Issue Date: October 2006 * DOI: https://doi.org/10.1038/ncprheum0281 SHARE THIS ARTICLE Anyone you share the following link with will

be able to read this content: Get shareable link Sorry, a shareable link is not currently available for this article. Copy to clipboard Provided by the Springer Nature SharedIt

content-sharing initiative