Clinical implications of elevated antiphospholipid antibodies in adult patients with primary immune thrombocytopenia.
OBJECTIVE
Antiphospholipid antibodies (aPL) have been detected in various proportions of patients with primary immune thrombocytopenia (ITP), but the clinical significance of this is debatable. The present study aimed to determine the frequency and clinical implications of elevated aPL in adult patients with ITP.


METHODS
We prospectively studied newly diagnosed adult patients with ITP who were enrolled between January 2003 and December 2008 at Chungnam National University Hospital. They were evaluated for the presence of lupus anticoagulant (LA) and anticardiolipin antibodies (aCL) at diagnosis and were followed for the development of thrombosis.


RESULTS
Seventy consecutive patients with ITP (median age, 48 years; range, 18 to 79) were enrolled. Twenty patients (28.5%) were positive for aPL at the time of diagnosis: aCL alone in 15 (75%), aCL and LA in two (10%), and LA alone in three (15%). Patients who had platelet counts < 50,000/µL were administered oral prednisolone with or without intravenous immune globulin. No difference was found between the aPL-positive and -negative groups regarding gender, initial platelet count, and response to the therapy. After a median follow-up of 20 months (range, 2 to 68), two of 20 patients who were aPL-positive (10%) developed thrombosis, whereas no thrombotic event was found among those who were aPL-negative.


CONCLUSIONS
Our data suggest that aPL levels should be determined at the initial presentation of ITP and that patients found to be aPL-positive should receive closer follow-up for thrombotic events.
Department of Internal Medicine, Daejeon Saint Mary's Hospital, The Catholic University of Korea School of Medicine, Daejeon, Korea.
Young-Joon
YJ
Yang
Gak-Won
GW
Yun
Ik-Chan
IC
Song
Seung-Woo
SW
Baek
Kyu-Seop
KS
Lee
Hye Won
HW
Ryu
Myung-Won
MW
Lee
Hyo-Jin
HJ
Lee
Hwan-Jung
HJ
Yun
Samyong
S
Kim
Deog-Yeon
DY
Jo
D000293:Adolescent; D000328:Adult; D000368:Aged; D017153:Antibodies, Anticardiolipin / Q000097:blood*; D017152:Antibodies, Antiphospholipid / Q000097:blood; D016009:Chi-Square Distribution; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D016682:Lupus Coagulation Inhibitor / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011239:Prednisolone / Q000627:therapeutic use; D011446:Prospective Studies; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000097:blood* / Q000188:drug therapy; D013920:Thrombocythemia, Essential / Q000097:blood* / Q000188:drug therapy; D013927:Thrombosis; D055815:Young Adult
D017153:Antibodies, Anticardiolipin; D017152:Antibodies, Antiphospholipid; D005938:Glucocorticoids; D016682:Lupus Coagulation Inhibitor; D011239:Prednisolone