Case Presentation:
A 62 year‐old woman with a history of persistent endometrial adenocarcinoma undergoing conservative treatment with megestrol presented with two episodes of vaginal bleeding and nausea. Initial vital signs and physical exam were unremarkable. Preliminary laboratory results were notable for a hematocrit of 22.2%, platelets 10,000/UL, and a creatinine of 1.99 mg/dL. Prior to admission, her last documented laboratory studies had a hematocrit of 31%, a platelet count of 117,000/UL, and a creatinine of 0.96 mg/dL. While being evaluated by the emergency room physicians, the gynecology consultation service, arranged for a platelet transfusion. Shortly after the platelet transfusion began, the patient developed right‐sided facial droop, hemiparesis, lethargy, and icteric sclera. A head CT showed no evidence of bleeding or acute ischemia. At that point, her hematocrit was decreased to 15.4%, her peripheral blood smear demonstrated 2+ schistocytes and the lactate dehydrogenase was 1189 U/L. She developed a low‐grade fever, but remained hemodynamically stable.
An emergent hematology consultant diagnosed thrombotic thrombocytopenic purpura. Plasma exchange apheresis and solumedrol therapy were initiated. Her creatinine peaked at 3.4 mg/dL and ultimately returned to normal. Additionally, there was resolution of her neurologic symptoms within a few hours and she had no episodes of further bleeding during the hospital stay.
Discussion:
Thrombocytopenia and anemia are laboratory abnormalities commonly encountered by hospitalists, and it is important to recognize when they may reflect a life‐threatening condition. A characteristic pentad can be seen in thrombotic thrombocytopenic purpura (TTP): fever, thrombocytopenia, microangiopathic hemolytic anemia (MAHA), neurological abnormalities, and renal impairment. However, less than ten percent of patients present with the full pentad. The combination of thrombocytopenia and MAHA, in the absence of disseminated intravascular coagulation, is enough to warrant initiation of treatment for TTP. Symptoms associated with TTP include weakness, anorexia, nausea, vomiting, and diarrhea. The laboratory results should include a peripheral blood smear with schistocytes, elevated lactate dehydrogenase, decreased haptoglobin, and a negative direct Coombs test.
TTP is a disorder of platelet aggregation, causing obstruction of arteriolar and capillary beds. This causes high shear rates of blood passing through the vessels, resulting in both increased platelet consumption and hemolysis of red blood cells, or MAHA. Causes of TTP include a deficiency or suppressed activity of ADAMTS13 caused by autoimmunity, certain medications, pregnancy, infection, and malignancy.
TTP has a mortality rate of 10‐20%, frequently due to delay in diagnosis or appropriate treatment. Treatment should be initiated with plasma exchange as soon as possible. If there is a delay in plasma exchange, fresh frozen plasma may be administered until plasma exchange can begin. High dose steroids are routinely given as adjuvant therapy. Platelet transfusion is contraindicated, as this may worsen the condition.
Conclusions:
Due to the emergent nature of TTP and the importance of rapid therapy, it is critical that the internist be able to recognize, diagnose, and treat this condition.