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microangiopathic hemolytic anemia (MAHA)
thrombotic microangiopathy (TMA)

causes of thrombotic microangiopathy

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primary thrombotic microangiopathies

TMA-associated conditions (a.k.a., “secondary TMA”)

TMA associated with rheumatologic disease
TMA associated with pregnancy – explored below.
TMA secondary to malignant hypertension
drug-induced TMA  (33841853)
infection-associated TMA
glomerular diseases associated with TMA
malignancy-associated TMA
transplantation-associated TMA
non-TMA entities to consider on the differential diagnosis

investigating the cause of TMA

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lab panel to evaluate the cause of a thrombotic microangiopathy

interpretation of labs to elucidate the etiology of TMA

complete blood count
coagulation labs
severity of renal failure (creatinine level)
ADAMTS13 tests
antinuclear antibodies (ANA)

initial empiric therapy for TMA

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initial treatment of TMA is a paradox

Therefore, empiric therapy must often precede definitive diagnosis.  Clinical judgement is required to rapidly assess the likelihood of TTP or C-HUS.  As laboratory data returns, the diagnosis and treatment may change (e.g., an initial empiric diagnosis of TTP may be changed to a diagnosis of probable C-HUS, after a normal ADAMTS13 level is reported).

empiric treatment for TTP with plasmapheresis and steroid

empiric eculizumab for C-HUS

introduction to TTP

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TTP results from the following sequence of events
congenital TTP (a.k.a., Upshaw-Schulman syndrome)

epidemiology of acquired TTP

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clinical presentation of TTP

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the classic pentad of TTP:
other symptoms:  

initial treatment of acquired TTP

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(#1) Fresh frozen plasma infusion while waiting for plasma exchange
(#2) plasmapheresis (a.k.a., plasma exchange)
(#3) immunosuppressive therapy
(#4) blood pressure control
(#5) avoid blood products (other than fresh frozen plasma)
(#6) Venous thromboembolism prophylaxis
(#7) antiplatelet therapy
(#8) myocardial infarction
(#9) caplacizumab

introduction to ST-HUS

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epidemiology and presentation of ST-HUS

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(#1) exposure
(#2) gastroenteritis
(#3) thrombotic microangiopathy

diagnosis of ST-HUS

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assays for ST-HUS
clinical value of a definitive diagnosis of ST-HUS

treatment of ST-HUS

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introduction to C-HUS

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clinical presentation of C-HUS

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(#0)  rarely, a history of C-HUS
(#1) preceding trigger
(#2) thrombotic microangiopathy

evaluation of C-HUS

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laboratory diagnostics are inadequate
diagnostic approach to C-HUS

treatment of C-HUS

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TMA in pregnancy or postpartum

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diagnosis of TMA in pregnancy or postpartum
differential diagnosis



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questions & discussion

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To keep this page small and fast, questions & discussion about this post can be found on another page here.

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