A 25-year-old pregnant lady presents with thrombocytopenia (Platelet count < 50,000) and fragmented RBC's in peripheral smear. Which of the following is the least likely differential diagnosis?

Answer is D (Evan's syndrome) Evan's syndrome is not a microangiopathic hemolytic condition and does not present with fragmented RBCs in the peripheral smear. Presence offragmented RBC's in the peripheral smear suggests the diagnosis of a micro-angiopathic process (Microangiopathic Hemolytic Anemia). The fragmentation of RBC's is caused by fibrin deposits in small blood vessels, which cause mechanical hemolysis. Patients with microangiopathic hemolytic anemias are usually thrombocytopenic (due to consumption of Platelets). Microangiopathic Hemolytic anemia (fragmented RBC) and Thrombocytopenia are typically seen in TTP, HUS, DIC and HELLP syndrome besides several other conditions. Evan's syndrome (combination of ITP and Autoimmune Hemolytic Anemia (AIHA)) Evan's Syndrome refers to a combination of Idiopathic Thrombocytopenie Purpura (ITP) and Autoimmune Hemolytic Anemia (AIHA) in the absence of an underlying cause / disease. The occurence of thrombocytopenia may coincide with episodes of hemolysis or may arise as separate episodes. Evan's syndrome is more common in children Evan's syndrome tends to be resistanct to management of Warm AIHA or ITP Evans syndrome presents with `Thrombocytopenia' and 'Immune Hemolysis'. Evan's syndrome does not present with microangiopathic features or fragmented RBCs. TTP, DIC and HELLP syndrome all may present with microangiopathic features (fragmented RBC's) and thrombocvtopenia Microangiopathic Hemolytic Anemias TTP HUS DIC Vasculitis (Collagen Vascular Disorders) Malignant Hypeension/Eclampsia/HELLP Disseminated carcinomatosis (Metastasis) Drugs/Radiation Antiphospholipid syndrome(NMS Medicine) Prosthetic Hea Valves (Pathologically Macroangiopathic - Ruhoi 's Pathology) Patients with microangiopathic hemolytic anemias are usually thrombocytopenic (due to consumption of Platelets).