All of the following are associated with coombs positive hemolytic anemia except -
Thrombotic thrombocytopenia purpura (TTP)
Scleroderma
SLE
PAN
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
Haematology