Blood Bank Exam 3: Autoimmune Hemolytic Anemia

What are the kinds of autoantibodies we talked about? (3)

warm

cold

drug induced

what stage of testing has the best reactivity for cold antibodies

room temp

what stage of testing has the best reactivity for warm antibodies

IAT

in order for an antibody finding to be relevant there need to be _____________ _____________________

clinical findings

is hemolytic anemia common?

no

ia hemolytic anemia a common cause of hemolysis?

yes

can healthy people have a positive DAT

yes

can AIHA happen without a positive DAT

yes

what are the two kinds of alloantibody induced hemolytic anemias?

hemolytic transfusion reactions

hemolytic disease of the newborn

what are the kinds of autoimmune hemolytic anemia?

warm antibody autoimmune hemolytic anemia

cold agglutinin syndrome

paroxysmal cold hemoglobinuria

atypical autoimmune hemolytic anemia

what is the third category of immune hemolytic anemia?

drug induced

what is the primary cause of WAIHA

idiopathic

what are the secondary causes of WAIHA (4)

lymphoma

SLE

carcinoma

other autoimmune diseases

what temperature is WAIHA reactive at

37 degrees Celsius

Commonality of WAIHA

most common cause of immune hemolysis

symptoms of autoimmune hemolytic anemia (5)

weakness

dizziness

dyspnea

angina

confusion

signs of autoimmune hemolytic anemia (6)

splenomegaly

hepatosplenomegaly

lymphadenopathy

jaundice

cardiac failure

fever

what do we see macroscopically in AIHA

hemolysis

what does hemolysis look like

what do we test in a DAT

polyspecific IgG and complement

monospecific IgG

monospecific complement

what percent of WAIHA is IgG and complement positive

67%

what percent of WAIHA is IgG positive alone

20%

what percent of WAIHA is complement positive alone

13%

what is the purpose of elution

remove Ab from RBC so that we can ID the Ab

what kind of elution do we do on AIHA

acid

when we test the eluate of warm auto antibodies, it is _____________

strongly positive

when we test the elute of drug dependent antibodies, it is _________________

negative or weak

in WAIHA, 50% of patients have ______________ in the serum

antibodies

when WAIHA patients go without treatment, they have increased _______________________________

antibodies in the plasma

what is the advantage of using LEISS

lowers TOT without enhancing the reaction

what is the advantage of saline/natural

does not enhance the reaction

what percent of pregnant or transfused patients have underlying alloantibodies

15-40%

what should we do when someone has an autoantibody to test for other antibodies?

adsorption

what is ZZAP and what does it do?

ZZAP is an in house/commercial solution which removes Ab from RBCs

what is adsorption

putting Ab onto RBCs

what is the procedure with adsorbtion (4)

remove Ab from RBCs (ZZAP)

incubate at 37

warm autoantibodies remain attached to the cell while other antibodies are free in the serum

free antibodies can be tested with a panel

one round of adsorption reduces the reactivity of autoantibodies by ______

1+ per adsorption

adsorption can be done with these kinds of cells

patients own

donors

when we have reactivity after adsorption, what does this mean?

there is an underlying antibody

when we don't have reactivity after adsorption, what does this mean?

there is no underlying antibody

is adsorption a fast test?

no

what should we do in an emergency situation while the lab is running an adsorption?

communicate with the emergency doctors

release blood anyways to transfuse

what is the treatment for WAIHA (5)

AVOID TRANSFUSION

steroids

transfuse for life threatening anemia

splenectomy

rituximab

what does rituximab do

removes b lymphs which create Ab

is there a cure for WAIHA?

no, we can only treat the symptoms

what does CHD stand for

cold hemagglutinin disease

what % of immune hemolysis is caused by CHD

16-25%

is CHD IgG or IgM

IgM

acute CHD has these predisposing factors (3)

lymphoproliferative disorder

mycoplasma pneumoniae infection

infectious mononucleosis

what population is acute CHD more common in

young

what population is chronic CHD more common in

elderly

mycoplasma pneumoniae is associated with this Ab

big I

infectious mononucleosis is associated with this AB

little i

when is chronic CHD more severe

during cold weather

cold hemagglutinin disease serology shows a DAT result which is only positive with this

complement

what are the antibody characteristics of cold hemagglutinin disease

increase in thermal amplitude

IgM antibody

cold hemagglutinin Ab is reactive at this temp

37

is it common to see a 4+ with cold hemagglutinin disease

no

what DAT are reactive in cold hemagglutinin disease

polyspecific AHG

complement

which antibody is most commonly associated with cold hemagglutinin disease

anti big I

what is the clinical manifestation of CHD (3)

mild chronic anemia

occasional jaundice and pallor

some have increased incidence when exposed to cold

when is CHD self limiting

when associated with mycoplasma or other viral infection

CHD is associated with this kind of hemolysis

intravascular

what signs and symptoms might we see with CHD (3)

hemoglobinuria

necrosis

RBC agglutination on the slide

how can CHD be managed (5)

no specific therapy if the anemia is mild and complicated

avoid cold temps

immunosuppressive therapy

plasmapheresis

C1 inhibitor

how should blood be transfused when a patient has CHD

through a blood warmer to avoid cold agglutination

which therapies are not helpful for CHD (3)

steroids

splenectomy

IVIG

what does PCH stand for

paroxysmal cold hemoglobinuria

what DAT is positive in paroxysmal cold hemoglobinuria

Complement only

what antibody is seen in paroxysmal cold hemoglobinuria (2)

donath landsteiner

Anti-P

what is the mechanism for paroxysmal cold hemoglobinuria

the antibody binds at a temperature <37 degrees

the RBC is lysed at 37 degrees

what is the treatment for paroxysmal cold hemoglobinuria (2)

self limiting

give P negative blood

what drug commonly causes DIAIHA

ceftriaxone

what happens in DIAIHA

rapid hemolysis

how do we differentiate DAIHA from other kinds of AIHA

DAIHA is negative when the eluate is tested

how does DAIHA function

drug binds and creates an epitope that is seen as foreign by the body

what drugs cause an autoantibody (3)

methyldopa (aldomet)

fludarabine

procainamide

MFP

what drugs cause a neoantigen (2)

quinidine

NSAIDs

what is the immune complex theory

drug alters the membrane without binding to the cell forming a new antigen that antibodies bind to.

what does NIPA stand for

non immunologic adsorption of protein into RBCs

what happens in NIPA

drugs cause the RBC to become sticky

what is the treatment for DIAIHA (4)

STOP THE DRUG

monitor vital signs (urine output, renal function, and Hgb)

intensive care may be required

some require temporary dialysis

what percent of DAIHA patients need a transfusion

50%