OBJECTIVETo study the current situation of coagulation factor VIII (FVIII) inhibitor development in children with hemophilia A (HA) through a cross-sectional survey, and to explore the risk factors of inhibitor development in order to provide evidence for further prevention and management strategies.

METHODThe clinical data of outpatients with hemophilia A in Beijing Children's Hospital seen from November 2012 to May 2013 were collected, FVIII inhibitor was screened and analyzed its risk factors.

RESULTA total of 102 HA children were enrolled, 5 were mild cases, 32 were moderate, and 65 were severe cases; the median age on enrollment was 55.5 (3.0-200.0) months:19(18.6%) of patients had inhibitors and 9 (8.8%) had low-titer inhibitors, 10 (9.8%) had high-titer inhibitors. Receiving FVIII treatment for life-threatening bleeding (P = 0.03) ,OR 4.10 (95%CI:1.17-14.32) was a risk factor for inhibitor generation and patients within 20 exposure days have more chances of inhibitor development (P = 0.04) ,OR 3.32 (95%CI:1.02-10.86) . High and intense FVIII exposure within short term was the risk factor for high titer inhibitor development (P = 0.01) ,OR 5.25 (95%CI:1.45-21.92) .

CONCLUSIONIntense FVIII exposure for severe hemorrhage was the risk factor of inhibitors development especially of high titer inhibitors.