Apheresis - Plasmapheresis

Question 1

What are the subtypes of Guillain-Barre Syndrome?

Answer 1

Classic is demyelinating (AIDP)
ASMAN/AMAN (axonal damage)
Miller-Fischer (ophthalmoplegia and ataxia)

Question 2

What is the treatment of Guillain-Barre Syndrome?

Answer 2

Respiratory support, TPE and/or IVIG (equivalent). Steroids are not helpful.

Question 3

What defines CIDP?

Answer 3

2+ months of chronic symptoms consistent with AIDP (motor/sensory loss).

Question 4

What is the treatment of CIDP?

Answer 4

TPE is first-line if severe. IVIG is comparably good.

Question 5

How is peripheral neuropathy with monoclonal gammopathy treated?

Answer 5

Because they are usually IgM-mediated, they should respond to plasma exchange. Exception: POEMS does not respond.

Question 6

What serologies are seen in Myasthenia Gravis?

Answer 6

Most cases have an anti-AChR, some have anti-MuSK, and some are seronegative.

Question 7

How is myasthenia gravis treated?

Answer 7

Symptomatic treatment (stigmines), immunosuppression, thymectomy (many a/w malignant thymoma), TPE or IVIG (equivalent)

Question 8

How does LEMS compare to MG?

Answer 8

LEMS patients may often present with pain, but not diplopia/dysarthria. TPE is somewhat less effective.

Question 9

What antibodies are implicated in LEMS?

Answer 9

Antibodies against presynaptic antigens, mostly P/Q/N voltage-gated calcium channels.

Question 10

Stiff-person syndrome

Answer 10

Caused by antibody to Glutamic Acid Decarboxylase, maybe Gephyrin. Extremely poorly described.

Question 11

MS/NMO

Answer 11

Not antibody-mediated, though NMO does have anti-aquaporin antibodies. NMO is better indication than MS, but reserve TPE for severe cases.

Question 12

How do the microthrombi in TTP differ from those in DIC?

Answer 12

TTP microthrombi generally lack fibrin and inflammatory cells.

Question 13

What are some causes of atypical hemolytic uremic syndrome?

Answer 13

Abnormalities of Factor H, Factor I, or CD46 (inborn deficiency vs acquired inihibitors)

Question 14

What are some secondary causes of thrombotic microangiopathies?

Answer 14

Infection (incl. HIV), CVDs (SLE), drugs (ticlopidine, quinine), pregnancy…

Question 15

What are the consequences of major incompatible ABO mismatched HSCT?

Answer 15

Hemolysis of red cells in product.
Delayed engraftment.
Pure red cell aplasia (destruction of normoblasts in product)

Question 16

What are the consequences of minor incompatible ABO mismatched HSCT?

Answer 16

Hemolysis of patient red cells, passenger lymphocyte syndrome

Question 17

How can apheresis be helpful pre-hSCT-transplant?

Answer 17

In major incompatibility, reduces isohemagglutinins. In minor incompatibility (RCX!), can “convert” patient’s type temporarily.

Question 18

What is the role of TPE in aplastic anemia?

Answer 18

Basically no role (not even in ASFA), despite some cases being immune-mediated (others: drug, virus, acquired clonal)

Question 19

What autoimmune hemolytic anemias should respond to TPE?

Answer 19

Cold hemolytic anemias moreso than warms, due to IgM more often than IgG (exception: PCH)

Question 20

What is the role of TPE in ITP?

Answer 20

Not great; ancient and scant data. Would not recommend.

Question 21

What is the role of TPE in hemophila?

Answer 21

Can reduce high-strength (>5 BU) inhibitors, but not really favored.

Question 22

What are the three types of cryoglobulinemias?

Answer 22

Type I: IgG or IgM monoclonal
Type II: IgM (mono) or IgG (poly); HCV-assoc
Type III: Polyclonal, associated with infection

Question 23

At what serum viscosity should patients become symptomatic?

Answer 23

Above 4-6x viscosity of water.

Question 24

How should TPE be timed with rituximab?

Answer 24

Always done before rituximab, both to not remove antibody and because of temporary IgM worsening with rituximab infusion.

Question 25

What is the recommended regimen for treatment of Goodpasture?

Answer 25

Exchange daily and at least partially with FFP.

Question 26

What is the role of TPE in treating the rapidly progressive glomerulonephritides?

Answer 26

Maybe some benefit if concomitant pulmonary hemorrhage (PEXIVAS?). ASFA categories range from I-III.

Question 27

How should myeloma cast nephropathies be treated?

Answer 27

Treat underlying myeloma. Mixed evidence for benefit of TPE. Standard dialysis will not remove free light chains.

Question 28

What is the role of TPE in lupus?

Answer 28

May actually worsen disease due to antibody rebound; reserve for severe cases or secondary complications like TTP or antiphospholipid syndrome.

Question 29

What is the role of TPE in scleroderma?

Answer 29

Mixed; ECP may be superior. Reserve for scleroderma renal crisis?

Question 30

What is the role of TPE in GVHD?

Answer 30

Extremely limited, due to markedly better efficacy of extracorporeal photopheresis.

Question 31

How can TPE be used in the pre- and post-transplant settings?

Answer 31

Pre: Reduce isohemagglutinins for ABO-incompatible transplants, reduce DSA/PRA pre-transplant.
Post: Reduce DSA, antibody-mediated rejection.

Question 32

What isohemagglutinin titer is recommended for safe ABO-incompatible transplant?

Answer 32

16

Question 33

How is recurrent FSGS treated?

Answer 33

TPE is first-line (as compared to primary FSGS, which is chronic and irreversible).

Question 34

What is the role of TPE in heart, liver, and lung transplant?

Answer 34

Not popular; cellular rejection is more common and is treated with ECP. HLA tolerizing is not practical pre-transplant. ECP also treats AMR…

Question 35

How does HUS present differently from TTP?

Answer 35

More renal manifestations, fewer neuro manifestations.

Question 36

What is the normal viscosity of plasma? At what levels can symptoms set in?

Answer 36

1.4 - 1.8 centipoise

Symptomatic hyperviscosity above 4 centripoise.

Question 37

At what plasma levels does each paraprotein isotype cause hyperviscosity?

Answer 37

IgM: 3 g/dL
IgG: 4 g/dL
IgA: 6 g/dL