Clinical ReviewsThrombotic Thrombocytopenic Purpura: A Hematological Emergency
Introduction
Thrombotic thrombocytopenic purpura (TTP) is a disorder of platelet aggregation resulting in hemolysis of red blood cells, consumption of platelets, and occlusion of microvasculature. TTP was first described in 1925, and its classic pentad of features—fever, thrombocytopenia, microangiopathic hemolytic anemia, neurologic abnormalities, and renal impairment—was noted in 1966 (1). Until its effective treatment became defined in 1991, 90% of patients with TTP ultimately died 1, 2.
Today, it is known that the classic pentad is not typically present, and the mortality rate of TTP is still approximately 20% 2, 3. Deaths are often a result of delays in diagnosis and implementation of the appropriate therapy, rendering TTP a hematological emergency (4). Given the range and variability of presenting symptoms, and its tendency to mimic more common disorders, outcome hinges on the emergency physician’s suspicion for and knowledge of this rare but rapidly fatal disease.
Section snippets
Epidemiology
The most recent analysis of the incidence of TTP was done in 2005, and found an annual incidence rate of patients treated for suspected TTP to be about 11 cases per 1,000,000 persons. This estimate is notably higher than previous ones based on death certificates and insurance claims. The same study noted that the incidence rate of TTP is greater in women than men, in Blacks than non-Blacks, and those living in urban settings than rural areas. The former two findings are consistent with the
Conclusion
TTP is a rare but true hematological emergency with fatal consequences if not promptly diagnosed and appropriately treated. Its presentation is variable with non-specific symptoms and imitates common disease processes, often leading clinicians to erroneous diagnoses and causing unaffordable delays. Thus, it is imperative for the emergency physician to be familiar with diagnostic and therapeutic guidelines.
TTP classically presents with fever, thrombocytopenia, microangiopathic hemolytic anemia,
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Cited by (27)
Thrombotic Microangiopathies (TTP, HUS, HELLP)
2017, Hematology/Oncology Clinics of North AmericaSuccessful resuscitation with thrombolysis of pulmonary embolism due to thrombotic thrombocytopenic purpura during cardiac arrest
2015, American Journal of Emergency MedicineTTP presenting as refractory hypoglycemia in a patient with thromboangiitis obliterans
2014, American Journal of Emergency MedicineCitation Excerpt :Fresh frozen plasma can be given if there is delay in plasmapheresis; however, fluid overload is a known complication of high-dose FFP for TTP [2,3,11,13]. Rituximab and high-dose glucocorticoids 10 mg/kg per day have been used as adjuvant therapy with plasmapheresis, especially treating and preventing refractory or relapsing cases of TTP [2,10-12]. Importantly, although anemia may be treated with platelet-depleted packed red blood cells, platelet infusion is generally contraindicated to prevent precipitation of additional thrombotic events, unless there is life-threatening hemorrhage [10,11].
Thrombotic microangiopathies (TTP, HUS, HELLP)
2014, Emergency Medicine Clinics of North AmericaCitation Excerpt :In another case series, common complaints described in more than one-third of patients included nausea, vomiting, diarrhea, abdominal pain, mild to severe weakness, and bleeding.9 Given presentations that are well short of the classically described pentad of symptoms, a more accurate definition for TTP is a microangiopathic hemolytic anemia (MAHA) and thrombocytopenia without other explanation.11,13 Physical examination findings correlate with the disease pathophysiology and represent end-organ damage.