All of the following are associated with coombs positive hemolytic anemia except -: (A) Thrombotic thrombocytopenia purpura (TTP), (B) Scleroderma, (C) SLE, (D) PAN
Answer is A. Coombs is positive only in immune hemolytic anemias where there is hemolysis of RBCs by antibodies produced in the body which is the case in SLE ,PAN & Scleroderma. While in TTP hemolysis occurs due to trauma to RBCs due to Microangiopathic hemolysis, seen in TTP &HUS Ref Robbins 9/e pg 448-449