**Differential diagnosis**

TTP, HUS and preeclampsia need to be differentiated as prognosis and treatment vary. The distinction between HUS-TTP and severe preeclampsia is often difficult. TTP is characterized by severe thrombocytopenia, hemolytic anemia, neurologic abnormalities (headache, altered consciousness, seizures, hemiparesis), and fever. Renal involvement may occur in 80% of cases of TTP; TTP occurs in 2nd /3rd trimester . von Willebrand factorcleaving protease (ADAMTS-13) activity <5 percent is seen in 33 to 100 percent of women with TTP.Unlike HELLP the condition may continue or worsen after delivery with TTP. If suspected preeclampsia/HELLP does not improve within 48-72 hours after delivery, consider TTP. TTP like HUS is associated with isolated platelet consumption; thus, although thrombocytopenia is seen, the other findings of DIC are typically absent. A peripheral blood smear can also be useful. The percentage of schistocytes on peripheral smear is higher in TTP (2 to 5 percent).

HUS is characterized by thrombocytopenia, hemolytic anemia, acute renal failure with proteinuria, hematuria, or oliguria/anuria). Neurological manifestations are uncommon. The absence of DIC, onset more than two days after delivery, and/or persistent disease for more than one week are the main findings that characterize HUS. Neurologic involvement may be seen in 50% of cases of HUS. A peripheral blood smear can also be useful. The percentage of schistocytes on peripheral smear is higher in HUS (2 to 5 percent).ADAMTS deficiency is rare in HUS.

History of preceding proteinuria and hypertension favor preeclampsia , preeclampsia-HELLP does not occur before 20 weeks of gestation and most cases are diagnosed in the third trimester. Delivery leads to resolution with preeclampsia, HELLP is associated with thrombocytopenia, and in severe cases, there may be DIC with prolongation of the PT and aPTT, and reductions in the plasma concentrations of factors V and VIII. The percentage of schistocytes on peripheral smear is low (<1%). ADAMTS deficiency is not seen in PIH.

In addition, only a few select laboratories are able to perform complementassociated mutational analysis. Studies of larger heterogeneous populations need to be performed before recommending genetic analysis for patients with pregnancy-associated TTP-HUS. It has not been shown that distinguishing TTP from HUS alters treatment of such patients.

shows petechiae, ecchymoses, and nose and gum bleeding . Rarely hematuria, gastrointestinal bleeding and intracranial bleeding may occur. Bleeding associated with surgery is uncommon unless the platelet counts are lower than 50,000/μ L. Clinically

Plasmapheresis is the recommended therapy. Plasmapheresis removes platelet-aggregating substances causing TTP. Treatment is 90% successful with TTP but is less successful with HUS. Steroids are used along with plasmapheresis. However, steroids are less effective than plasmapheresis (25% response rate).Platelet transfusions should be avoided when possible because they can cause a clinical deterioration. Platelet transfusions should be used only for uncontrolled bleeding or intracranial hemorrhage. Other therapies include immunosuppressive agents (vincristine, azathioprine, cyclosporine)and splenectomy for TTP. Premature termination of pregnancy has been associated with relapse. Delivery should

TTP, HUS and preeclampsia need to be differentiated as prognosis and treatment vary. The distinction between HUS-TTP and severe preeclampsia is often difficult. TTP is characterized by severe thrombocytopenia, hemolytic anemia, neurologic abnormalities (headache, altered consciousness, seizures, hemiparesis), and fever. Renal involvement may occur in 80% of cases of TTP; TTP occurs in 2nd /3rd trimester . von Willebrand factorcleaving protease (ADAMTS-13) activity <5 percent is seen in 33 to 100 percent of women with TTP.Unlike HELLP the condition may continue or worsen after delivery with TTP. If suspected preeclampsia/HELLP does not improve within 48-72 hours after delivery, consider TTP. TTP like HUS is associated with isolated platelet consumption; thus, although thrombocytopenia is seen, the other findings of DIC are typically absent. A peripheral blood smear can also be useful. The percentage of schistocytes on peripheral smear is higher in

HUS is characterized by thrombocytopenia, hemolytic anemia, acute renal failure with proteinuria, hematuria, or oliguria/anuria). Neurological manifestations are uncommon. The absence of DIC, onset more than two days after delivery, and/or persistent disease for more than one week are the main findings that characterize HUS. Neurologic involvement may be seen in 50% of cases of HUS. A peripheral blood smear can also be useful. The percentage of schistocytes on peripheral smear is higher in HUS (2 to 5 percent).ADAMTS

History of preceding proteinuria and hypertension favor preeclampsia , preeclampsia-HELLP does not occur before 20 weeks of gestation and most cases are diagnosed in the third trimester. Delivery leads to resolution with preeclampsia, HELLP is associated with thrombocytopenia, and in severe cases, there may be DIC with prolongation of the PT and aPTT, and reductions in the plasma concentrations of factors V and VIII. The percentage of schistocytes on peripheral smear is low (<1%). ADAMTS deficiency is not

In addition, only a few select laboratories are able to perform complementassociated mutational analysis. Studies of larger heterogeneous populations need to be performed before recommending genetic analysis for patients with pregnancy-associated TTP-HUS. It has not been shown that distinguishing TTP from HUS alters treatment of such

significant spontaneous bleeding is rare unless counts fall below 10,000/μ L.

be considered only when no response to other therapies occurs. (George JN, 2010)

**Treatment** 

**Differential diagnosis** 

TTP (2 to 5 percent).

deficiency is rare in HUS.

seen in PIH.

patients.
