Cyclophosphamide and Hydroxychloroquine for Thrombocytopenia in SLE

Inclusion Criteria:

1. Patients fulfilled the 1997 ACR modified or SLICC classification criteria of SLE；
2. New onset thrombocytopenia: platelet count <30X109/L(by both routine test and citricacid anti-coagulated blood count test) within 3 months

Exclusion Criteria:

1. Thrombocytopenia caused by other reasons, including drugs；
2. Positive for active HAV(hepatitis A virus)/HBV(hepatitis B virus) infection
3. Active HIV(human immunodeficiency virus) or HCV(hepatitis C virus) infection;
4. Active HP(Helicopter pylori) infection;
5. Severe liver and kidney dysfunction；
6. Severe neuropsychiatric lupus；
7. No response to high dose steroid and/or cyclophosphamide 1 month prior to studyenrollment；
8. Uncontrolled diabetes or hypertension before entry
9. Active GI bleeding 3 months before entry
10. Intolerant to HCQ in the past treatment history；
11. Severe bone marrow suppression or liver damage caused by cyclophosphamide in the pasthistory；
12. Active infection , including bacteria, virus, fungi, mycobacteria
13. Allergy to any of the study medications
14. Confirmed TTP(thrombolic thrombocytopenic purpura)or CAPS(catastrophicanti-phosphilipid syndrome)
15. Platelet count less than 20X109/L with active bleeding
16. Myelodysplastic diseases
17. Patients with heart and lung function impairment
18. thiopurine S-methyltransferase (TPMT) gene positive -