All of the following conditions are associated with coombs positive hemolytic anemia, except:
Thrombotic Thrombocytopenic purpura (TTP), shows coomb's negative microangiopathic hemolytic anemia. Ref: Amit Ghosh, MD (2010), Chapter 11, "Hematology: Benign Hematology", In the book, "Mayo Clinic Internal Medicine Board Review", 9th Edition, New york, Page 378; Harrison's Principles of Internal Medicine, 16th Edition, Page 612
Thrombotic Thrombocytopenic purpura (TTP)
Scleroderma
SLE
PAN