Diagnosing, treating TTP promptly improves pregnancy outcomes
Overlap with HELLP syndrome, other conditions, complicates care
Acquired thrombotic thrombocytopenic purpura (TTP) during pregnancy must be distinguished from other conditions, monitored carefully, and treated promptly to ensure the best possible outcomes for both the mother and infant, a case report about a woman who’d been misdiagnosed during her first pregnancy suggests.
The woman was successfully treated for TTP during her second pregnancy, but her baby had to be delivered prematurely and didn’t survive.
“Our case report and literature review highlight the importance of early diagnosis, timely intervention, and continuous surveillance to ensure positive maternal and fetal outcomes,” the study’s researchers wrote. The case study was detailed in a short communication titled, “Navigating recurrent immune-mediated thrombotic thrombocytopenic purpura (iTTP) in pregnancy: A case report and literature review” in Transfusion and Apheresis Science.
People with TTP lack enough of a functional enzyme called ADAMTS13 that prevents the cell fragments, or platelets, involved in initiating blood clotting after an injury from forming clots when they’re not needed. As a result, tiny clots form inside blood vessels when they shouldn’t, leading to organ damage, red blood cell destruction, called hemolytic anemia, and a depleted platelet supply (thrombocytopenia).
The most common form of TTP is immune-mediated, or acquired, with the loss of ADAMTS13 occuring because the immune system mistakenly produces self-reactive antibodies that target the enzyme.
This type of TTP mainly affects women of childbearing age, with up to 25% of adult-onset cases being preceded by pregnancy, according to the researchers. Women who have acquired TTP during one pregnancy are at risk of it happening again, so they must be closely monitored and sometimes preventively treated in subsequent pregnancies.
The condition can be life threatening to both mother and infant, but advances in treatment and care have substantially improved outcomes.
Second pregnancy brings TTP recurrence
Starting an appropriate treatment depends on diagnosing the condition accurately, however. This is complicated by the fact that TTP resembles other pregnancy-related conditions, such as HELLP syndrome, which is marked by hemolysis, elevated liver enzymes, thrombocytopenia, and preeclampsia, a serious high blood pressure-related complication.
The woman, 32, in the report was mistakenly diagnosed with HELLP syndrome in her first pregnancy, which happened three years before her second one. During it, she had signs of thrombocytopenia and bleeding under her skin. The diagnosis resulted in her baby being delivered early.
Even after the delivery, the woman had persistent thrombocytopenia and testing revealed anti-ADAMTS13 antibodies and low ADAMTS13 enzyme activity, resulting in a diagnosis of acquired TTP.
She was successfully treated with therapeutic plasma exchange (TPE) where the liquid part of blood, called plasma, is removed and replaced with that of a healthy donor, along with high-dose steroids. She remained in remission and the steroids were tapered off.
The woman remained disease-free for three years, but her symptoms returned during her next pregnancy when she fainted during a blood draw, and had signs of TTP, including red and purple dots on her skin (petechiae), bruising, and thrombocytopenia. Lab tests showed signs of thrombocytopenia, hemolytic anemia, and low ADAMTS13 activity.
She was promptly treated with TPE and steroids, and she improved after three TPE sessions and was discharged from the hospital 15 weeks into her pregnancy. The woman was closely monitored and remained on steroids, but no more TPE was needed.
She later had pregnancy complications that required an emergency cesarean section during her second trimester and the infant didn’t survive. The woman was discharged from the hospital and discontinued on steroids due to persistent stomach irritation.
The study “highlights the importance of prompt and aggressive treatment to manage acute TTP episodes during pregnancy,” wrote the researchers, who noted the importance of distinguishing TTP from HELLP to ensure the right therapeutic strategy is implemented as soon as possible. They said the best outcomes will be achieved with a multidisciplinary approach that involves “regular ADAMTS-13 activity monitoring and prompt initiation of TPE and corticosteroids as first-line therapy.”
“Future research should aim to refine these strategies to optimize care for pregnant women with a history of TTP,” they wrote.
About the Author
