12-3 L2 Clincial microangiopathies Flashcards
1
Q
What is the diagnostic ‘pentad’ seen in TTP pts.
A
- Neurologic symptoms
- fever
- thrombocytopenia
- microangiopathic hemolytic anemia
- renal abnormalites
2
Q
describe the difference b/t acquired TTP and congenital TTP
A
- acquired TTP: due to IgG autoantibodies
- Congenital TTP: due to mutations in ADAMTS13 gene assocaited with absent/low levels (<5%) of ADAMTS13
3
Q
What is the treatement of TTP
prognosis
A
- Plasma exchange
- replaces ADAMTS13 and remvoes antibodies to ADAMTS-13
- Rituximab
- Prognosis: 90% survival
4
Q
name 2 types of hemolytic uremic syndrome
A
- Shiga toxin (Stx) associated HUS
- Non-Stx associated HUS (atypical HUS)
5
Q
What causes Stx-Associated HUS
A
-
E. coli serotype O157:H7
- which produce shigatoxin
6
Q
STX pahtology seen where/cell type
results in what 2 things?
A
- endothelial damage (glomerular EC)
- intracellularly blocks protein synthesis and induces apoptios
- **Results: **endothelial damage and microvascular thrombosis
7
Q
name common lab findings to diagnosis HUS
A
-
Mechanical hemolytic anemia
- DAT (coombs test) negative
- hemolysis
- Schistocytes
- Thrombocytopenia
- Renal failure
- Stool culture (PCR)
8
Q
presentation of
Atypical HUS
A
- Clinical triad: microangiopahtic hemolytic anemai, thrombocytopenia and acute renal injury
*
9
Q
Pathologenesis of aHUS
- loss of function (4 things)
- gain of function (2 things)
A
- loss of function (4 things)
- Complement factor H,I,
- Membrane cofactor protein (MCP)
- Thrombomodulin (THBD)
- gain of function (2 things)
- C3
- Factor B
10
Q
How to identify between
TTP, HUS, aHUS
A
- TTP: check for ADAMTS-13 def
- HUS: check for *E. coli *O157H7
- aHUS: check for complement def
11
Q
provide two treatments for aHUS
A
- Plasma therapy
- Eculizamb
12
Q
MOA
Eculizamab
A
- humanized monoclonal antibody against complement factor C5
- recently approved by the FDA for treatment of aHUS
